Runoff and Infiltration Dynamics on Pervious Paver Surfaces

USDA-ARS?s Scientific Manuscript database

When natural or agricultural land is converted for (sub)urban or commercial use, the addition of impervious surfaces becomes a dominating factor in the new urban hydrologic regime. To help minimize the negative hydrologic effects of this land use change, urban best management practices (BMPs) are co...

Impacts of urbanization and agricultural development on observed changes in surface air temperature over mainland China from 1961 to 2006

NASA Astrophysics Data System (ADS)

Han, Songjun; Tang, Qiuhong; Xu, Di; Yang, Zhiyong

2018-03-01

A large proportion of meteorological stations in mainland China are located in or near either urban or agricultural lands that were established throughout the period of rapid urbanization and agricultural development (1961-2006). The extent of the impacts of urbanization and agricultural development on observed air temperature changes across different climate regions remains elusive. This study evaluates the surface air temperature trends observed by 598 meteorological stations in relation to the urbanization and agricultural development over the arid northwest, semi-arid intermediate, and humid southeast regions of mainland China based on linear regressions of temperature trends on the fractions of urban and cultivated land within a 3-km radius of the stations. In all three regions, the stations surrounded by large urban land tend to experience rapid warming, especially at minimum temperature. This dependence is particularly significant in the southeast region, which experiences the most intense urbanization. In the northwest and intermediate regions, stations surrounded by large cultivated land encounter less warming during the main growing season, especially at the maximum temperature changes. These findings suggest that the observed surface warming has been affected by urbanization and agricultural development represented by urban and cultivated land fractions around stations in with land cover changes in their proximity and should thus be considered when analyzing regional temperature changes in mainland China.

Spatio-Temporal Analysis of Urban Heat Island and Urban Metabolism by Satellite Imagery over the Phoenix Metropolitan Area

NASA Astrophysics Data System (ADS)

Zhao, Q.; Zhan, S.; Kuai, X.; Zhan, Q.

2015-12-01

The goal of this research is to combine DMSP-OLS nighttime light data with Landsat imagery and use spatio-temporal analysis methods to evaluate the relationships between urbanization processes and temperature variation in Phoenix metropolitan area. The urbanization process is a combination of both land use change within the existing urban environment as well as urban sprawl that enlarges the urban area through the transformation of rural areas to urban structures. These transformations modify the overall urban climate environment, resulting in higher nighttime temperatures in urban areas compared to the surrounding rural environment. This is a well-known and well-studied phenomenon referred to as the urban heat island effect (UHI). What is unknown is the direct relationship between the urbanization process and the mechanisms of the UHI. To better understand this interaction, this research focuses on using nighttime light satellite imagery to delineate and detect urban extent changes and utilizing existing land use/land cover map or newly classified imagery from Landsat to analyze the internal urban land use variations. These data are combined with summer and winter land surface temperature data extracted from Landsat. We developed a time series of these combined data for Phoenix, AZ from 1992 to 2013 to analyze the relationships among land use change, land surface temperature and urban growth.

Investigating the vertical dimension of Singapore's urban heat island through quadcopter platforms: an pilot study

NASA Astrophysics Data System (ADS)

Chow, Winston; Ho, Dawn

2016-04-01

In numerous cities, measurements of urban warmth in most urban heat island (UHI) studies are generally constrained towards surface or near-surface (<2 m above surface level) levels across horizontal variations in land use and land cover. However, there has been hitherto limited attention towards the measurement of vertical temperature profiles extending from the urban surface, urban canopy layer through to the urban boundary layer. Knowledge of these profiles, through (a.) how they vary over different local urban morphologies, and (b.) develop with respect to synoptic meteorological conditions, are important towards several aspects of UHI research; these include validating modelling urban canopy lapse rate profiles or estimating the growth of urban plumes. In this novel study, we utilised temperature sensor-loggers attached onto remote controlled aerial quadcopter platforms to measure urban temperature profiles up to 100 m above ground level in Singapore, which is a rapidly urbanizing major tropical metropolis. Three different land use/land cover categories were sampled; a high-rise residential estate, a university campus, and an urban park/green-space. Sorties were flown repeatedly at four different times - sunrise, noon, sunset and midnight. Initial results indicate significant variations in intra-site stability and inversion development between the urban canopy and boundary layers. These profiles are also temporally dynamic, depending on the time of day and larger-scale weather conditions.

What are hot and what are not in an urban landscape: quantifying and explaining the land surface temperature pattern in Beijing, China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuang, Wenhui; Liu, Yue; Dou, Yinyin

Understanding how landscape components affect the urban heat islands is crucial for urban ecological planning and sustainable development. The purpose of this research was to quantify the spatial pattern of land surface temperatures (LSTs) and associated heat fluxes in relation to land-cover types in Beijing, China, using portable infrared thermometers, thermal infrared imagers, and the moderate resolution imaging spectroradiometer. The spatial differences and the relationships between LSTs and the hierarchical landscape structure were analyzed with in situ observations of surface radiation and heat fluxes. Large LST differences were found among various land-use/land-cover types, urban structures, and building materials. Within themore » urban area, the mean LST of urban impervious surfaces was about 6–12°C higher than that of the urban green space. LSTs of built-up areas were on average 3–6°C higher than LSTs of rural areas. The observations for surface radiation and heat fluxes indicated that the differences were caused by different fractions of sensible heat or latent heat flux in net radiation. LSTs decreased with increasing elevation and normalized difference vegetation index. Variations in building materials and urban structure significantly influenced the spatial pattern of LSTs in urban areas. By contrast, elevation and vegetation cover are the major determinants of the LST pattern in rural areas. In summary, to alleviate urban heat island intensity, urban planners and policy makers should pay special attention to the selection of appropriate building materials, the reasonable arrangement of urban structures, and the rational design of landscape components.« less

What are hot and what are not in an urban landscape: quantifying and explaining the land surface temperature pattern in Beijing, China

DOE PAGES

Kuang, Wenhui; Liu, Yue; Dou, Yinyin; ...

2014-12-06

Understanding how landscape components affect the urban heat islands is crucial for urban ecological planning and sustainable development. The purpose of this research was to quantify the spatial pattern of land surface temperatures (LSTs) and associated heat fluxes in relation to land-cover types in Beijing, China, using portable infrared thermometers, thermal infrared imagers, and the moderate resolution imaging spectroradiometer. The spatial differences and the relationships between LSTs and the hierarchical landscape structure were analyzed with in situ observations of surface radiation and heat fluxes. Large LST differences were found among various land-use/land-cover types, urban structures, and building materials. Within themore » urban area, the mean LST of urban impervious surfaces was about 6–12°C higher than that of the urban green space. LSTs of built-up areas were on average 3–6°C higher than LSTs of rural areas. The observations for surface radiation and heat fluxes indicated that the differences were caused by different fractions of sensible heat or latent heat flux in net radiation. LSTs decreased with increasing elevation and normalized difference vegetation index. Variations in building materials and urban structure significantly influenced the spatial pattern of LSTs in urban areas. By contrast, elevation and vegetation cover are the major determinants of the LST pattern in rural areas. In summary, to alleviate urban heat island intensity, urban planners and policy makers should pay special attention to the selection of appropriate building materials, the reasonable arrangement of urban structures, and the rational design of landscape components.« less

Urban effects on regional climate: a case study in the Phoenix and Tucson ‘sun’ corridor

USGS Publications Warehouse

Zhao Yang,; Francina Dominguez,; Hoshin Gupta,; Xubin Zeng,; Norman, Laura M.

2016-01-01

Land use and land cover change (LULCC) due to urban expansion alter the surface albedo, heat capacity, and thermal conductivity of the surface. Consequently, the energy balance in urban regions is different from that of natural surfaces. To evaluate the changes in regional climate that could arise due to projected urbanization in the Phoenix-Tucson corridor, Arizona, we applied the coupled WRF-NOAH-UCM (which includes a detailed urban radiation scheme) to this region. Land cover changes were represented using land cover data for 2005 and projections to 2050, and historical North American Regional Reanalysis (NARR) data were used to specify the lateral boundary conditions. Results suggest that temperature changes will be well defined, reflecting the urban heat island (UHI) effect within areas experiencing LULCC. Changes in precipitation are less robust, but seem to indicate reductions in precipitation over the mountainous regions northeast of Phoenix and decreased evening precipitation over the newly-urbanized area.

Urban Heat Island ın Ankara

NASA Astrophysics Data System (ADS)

Yılmaz, Erkan

2016-04-01

In this study, the seasonal variation of the surface temperature of Ankara urban area and its enviroment have been analyzed by using Landsat 7 image. The Landsat 7 images of each month from 2007 to 2011 have been used to analyze the annually changes of the surface temperature. The land cover of the research area was defined with supervised classification method on the basis of the satellite image belonging to 2008 July. After determining the surface temperatures from 6-1 bands of satellite images, the monthly mean surface temperatures were calculated for land cover classification for the period between 2007 and 2011. According to the results obtained, the surface temperatures are high in summer and low in winter from the airtemperatures. all satellite images were taken at 10:00 am, it is found that urban areas are cooler than rural areas at 10:00 am. Regarding the land cover classification, the water surfaces are the coolest surfaces during the whole year.The warmest areas are the grasslands and dry farming areas. While the parks are warmer than the urban areas during the winter, during the summer they are cooler than artificial land covers. The urban areas with higher building density are the cooler surfaces after water bodies.

Evaluate the urban effect on summer convective precipitation by coupling a urban canopy model with a Regional Climate Model

NASA Astrophysics Data System (ADS)

Liu, Z.; Liu, S.; Xue, Y.; Oleson, K. W.

2013-12-01

One of the most significant urbanization in the world occurred in Great Beijing Area of China during the past several decades. The land use and land cover changes modifies the land surface physical characteristics, including the anthropogenic heat and thermo-dynamic conduction. All of those play important roles in the urban regional climate changes. We developed a single layer urban canopy module based on the Community Land Surface Model Urban Module (CLMU). We have made further improvements in the urban module: the energy balances on the five surface conditions are considered separately: building roof, sun side and shade side wall, pervious and impervious land surface. Over each surface, a method to calculate sky view factor (SVF) is developed based on the physically process while most urban models simply provide an empirical value; A new scheme for calculating the latent heat flux is applied on both wall and impervious land; anthropogenic heat is considered in terms of industrial production, domestic wastes, vehicle and air condition. All of these developments improve the accuracy of surface energy balance processing in urban area. The urban effect on summer convective precipitation under the unstable atmospheric condition in the Great Beijing Area was investigated by simulating a heavy rainfall event in July 21st 2012. In this storm, strong meso-scale convective complexes (MCC) brought precipitation of averagely 164 mm within 6 hours, which is the record of past 60 years in the region. Numerical simulating experiment was set up by coupling MCLMU with WRF. Several condition/blank control cases were also set up. The horizontal resolution in all simulations was 2 km. While all of the control results drastically underestimate the urban precipitation, the result of WRF-MCLMU is much closer to the observation though still underestimated. More sensitive experiments gave a preliminary conclusion of how the urban canopy physics processing affects the local precipitation: the existence of large area of impervious surfaces restrain the surface evaporation and latent heat flux in urban while the anthropogenic heat and enhanced sensible heat flux warm up the lower atmospheric layer and strengthen the vertical stratification instability; In this storm event, the water supply of the MCC was thought to be sufficient, thus the instability of the vertical stratification was the key factor for precipitation.

Exploring the Influence of Impervious Surface Density and Shape on Urban Heat Islands in the Northeast USA Using MODIS and Landsat

NASA Technical Reports Server (NTRS)

Zhang, Ping; Imhoff, Marc L.; Bounoua, Lahouri; Wolfe, Robert E.

2011-01-01

Impervious surface area (ISA) from the National Land Cover Database (NLCD) 2001 and land surface temperature (LST) from MODIS averaged over three annual cycles (2003-2005) are used in a spatial analysis to assess the urban heat island (UHI) signature and its relationship to settlement size and shape, development intensity distribution, and land cover composition for 42 urban settlements embedded in forest biomes in the Northeastern United States. Development intensity zones, based on percent ISA, are defined for each urban area emanating outward from the urban core to nearby rural areas and are used to stratify land surface temperature. The stratification is further constrained by biome type and elevation to insure objective intercomparisons between urban zones within an urban settlement and between settlements. Stratification based on ISA allows the definition of hierarchically ordered urban zones that are consistent across urban settlements and scales. In addition to the surrounding ecological context, we find that the settlement size and shape as well as the development intensity distribution significantly influence the amplitude of summer daytime UHI. Within the Northeastern US temperate broadleaf mixed forest, UHI magnitude is positively related to the logarithm of the urban area size. Our study indicates that for similar urban area sizes, the development intensity distribution is one of the major drivers of UHI. In addition to urban area size and development intensity distribution, this analysis shows that both the shape of the urban area and the land cover composition in the surrounding rural area play an important role in modulating the UHI magnitude in different urban settlements. Our results indicate that remotely sensed urban area size and shape as well as the development intensity distribution influence UHI amplitude across regional scales.

Effects of urbanization on stream ecosystems along an agriculture-to-urban land-use gradient, Milwaukee to Green Bay, Wisconsin, 2003-2004

USGS Publications Warehouse

Richards, Kevin D.; Scudder, Barbara C.; Fitzpatrick, Faith A.; Steuer, Jeffery J.; Bell, Amanda H.; Peppler, Marie C.; Stewart, Jana S.; Harris, Mitchell A.

2010-01-01

In 2003 and 2004, 30 streams near Milwaukee and Green Bay, Wisconsin, were part of a national study by the U.S. Geological Survey to assess urbanization effects on physical, chemical, and biological characteristics along an agriculture-to-urban land-use gradient. A geographic information system was used to characterize natural landscape features that define the environmental setting and the degree of urbanization within each stream watershed. A combination of land cover, socioeconomic, and infrastructure variables were integrated into a multi-metric urban intensity index, scaled from 0 to 100, and assigned to each stream site to identify a gradient of urbanization within relatively homogeneous environmental settings. The 35 variables used to develop the final urban intensity index characterized the degree of urbanization and included road infrastructure (road area and road traffic index), 100-meter riparian land cover (percentage of impervious surface, shrubland, and agriculture), watershed land cover (percentage of impervious surface, developed/urban land, shrubland, and agriculture), and 26 socioeconomic variables (U.S. Census Bureau, 2001). Characteristics examined as part of this study included: habitat, hydrology, stream temperature, water chemistry (chloride, sulfate, nutrients, dissolved and particulate organic and inorganic carbon, pesticides, and suspended sediment), benthic algae, benthic invertebrates, and fish. Semipermeable membrane devices (SPMDs) were used to assess the potential for bioconcentration of hydrophobic organic contaminants (specifically polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine and pyrethroid insecticides) in biological membranes, such as the gills of fish. Physical habitat measurements reflective of channel enlargement, including bankfull channel size and bank erosion, increased with increasing urbanization within the watershed. In this study, percentage of riffles and streambed substrate size were more strongly related to local geologic setting, slope, watershed topography, and river-engineering practices than to urbanization. Historical local river-engineering features such as channelization, bank stabilization, and grade controls may have confounded relations among habitat characteristics and urbanization. A number of hydrologic-condition metrics (including flashiness and duration of high flow during pre- or post-ice periods) showed strong relations to the urban intensity index. Hydrologic-condition metrics cannot be used alone to predict habitat or geomorphic change. Chloride and SPMD measures of potential toxicity and polycyclic aromatic hydrocarbon concentrations showed the strongest positive correlations to urbanization including increases in road infrastructure, percentage of impervious surface in the watershed, urban land cover, and land-distribution related to urban land cover. This suggests that automobiles and the infrastructure required to support automobiles are a significant source of these compounds in this study area. Chloride in spring and summer showed a significant positive correlation with the urban intensity index; concentrations increased with increasing road infrastructure, urban land cover, and a number of landscape variables related to urbanization. Spring concentrations of sulfate, prometon, and diazinon correlated to fewer urban characteristics than chloride, including increases in road infrastructure, percentage of impervious surface, and urban land cover. Changes in biological communities correlated to the urban intensity index or individual urban-associated variables. Decreased percentages of pollution-sensitive diatoms and diatoms requiring high dissolved-oxygen saturation correlated to increases in the percentage of developed urban land, total impervious surface, stream flashiness, population density, road-area density, and decreases in the percentage of wetland in the watershed. Invertebrate taxa richness and Coleop

Observing the Vertical Dimensions of Singapore's Urban Heat Island

NASA Astrophysics Data System (ADS)

Chow, W. T. L.; Ho, D. X. Q.

2015-12-01

In numerous cities, measurements of urban warmth in most urban heat island (UHI) studies are generally constrained towards surface or near-surface (<2 m above ground) levels across horizontal variations in land use and land cover. However, there has been hitherto limited attention towards the measurement of vertical temperature profiles extending from the urban surface through to the urban boundary layer. Knowledge of these profiles, through how they vary over different local urban morphologies, and develop with respect to synoptic meteorological conditions, are important towards several aspects of UHI research; these include validating modelling urban canopy lapse rate profiles or estimating the growth of urban plumes. In this study, we utilised temperature sensors attached onto remote controlled aerial quadcopter platforms to measure urban temperature and humidity profiles in Singapore, which is a rapidly urbanizing major tropical metropolis. These profiles were measured from the surface to ~100 m above ground level, a height which includes all of the urban canopy and parts of the urban boundary layer. Initial results indicate significant variations in stability measured over different land uses (e.g. urban park, high-rise residential, commercial); these profiles are also temporally dynamic, depending on the time of day and larger-scale weather conditions.

A global analysis of the urban heat island effect based on multisensor satellite data

NASA Astrophysics Data System (ADS)

Xiao, J.; Frolking, S. E.; Milliman, T. E.; Schneider, A.; Friedl, M. A.

2017-12-01

Human population is rapidly urbanizing. In much of the world, cities are prone to hotter weather than surrounding rural areas - so-called `urban heat islands' - and this effect can have mortal consequences during heat waves. During the daytime, when the surface energy balance is driven by incoming solar radiation, the magnitude of urban warming is strongly influenced by surface albedo and the capacity to evaporate water (i.e., there is a strong relationship between vegetated land fraction and the ratio of sensible to latent heat loss or Bowen ratio). At nighttime, urban cooling is often inhibited by the thermal inertia of the built environment and anthropogenic heat exhaust from building and transportation energy use. We evaluated a suite of global remote sensing data sets representing a range of urban characteristics against MODIS-derived land-surface temperature differences between urban and surrounding rural areas. We included two new urban datasets in this analysis - MODIS-derived change in global urban extent and global urban microwave backscatter - along with several MODIS standard products and DMSP/OLS nighttime lights time series data. The global analysis spanned a range of urban characteristics that likely influence the magnitude of daytime and/or nighttime urban heat islands - urban size, population density, building density, state of development, impervious fraction, eco-climatic setting. Specifically, we developed new satellite datasets and synthesizing these with existing satellite data into a global database of urban land surface parameters, used two MODIS land surface temperature products to generate time series of daytime and nighttime urban heat island effects for 30 large cities across the globe, and empirically analyzed these data to determine specifically which remote sensing-based characterizations of global urban areas have explanatory power with regard to both daytime and nighttime urban heat islands.

Use of GLOBE Observations to Derive a Landsat 8 Split Window Algorithm for Urban Heat Island

NASA Astrophysics Data System (ADS)

Fagerstrom, L.; Czajkowski, K. P.

2017-12-01

Surface temperature has been studied to investigate the warming of urban climates, also known as urban heat islands, which can impact urban planning, public health, pollution levels, and energy consumption. However, the full potential of remotely sensed images is limited when analyzing land surface temperature due to the daunting task of correcting for atmospheric effects. Landsat 8 has two thermal infrared sensors. With two bands in the infrared region, a split window algorithm (SWA), can be applied to correct for atmospheric effects. This project used in situ surface temperature measurements from NASA's ground observation program, the Global Learning and Observations to Benefit the Environment (GLOBE), to derive the correcting coefficients for use in the SWA. The GLOBE database provided land surface temperature data that coincided with Landsat 8 overpasses. The land surface temperature derived from Landsat 8 SWA can be used to analyze for urban heat island effect.

Effects of urbanization on stream quality at selected sites in the seacoast region in New Hampshire, 2001-03

USGS Publications Warehouse

Deacon, Jeffrey R.; Soule, Sally A.; Smith, Thor E.

2005-01-01

A study of selected water-quality and macroinvertebrate community data was conducted at 10 stream sites in the Seacoast region of New Hampshire to determine if a relation is present between stream quality and the extent of urbanization in a watershed. Watersheds with similar characteristics, but varying in their degree of urban development, were studied. The percent of impervious surface, the percent of urban land use in a watershed, and the percent of urban land use in two types of stream buffers were compared and correlated with stream-quality variables. Specific conductance, turbidity, nitrite plus nitrate yields, and selected macroinvertebrate community data were significantly correlated with most measures of urbanization used in this study; however, concentrations and total phosphorus yields were not statistically correlated with most measures of urbanization in this study. The measures of urbanization that had the highest correlations with stream-quality variables were those measures that were associated with the percent of urban land in buffer zones near and upstream of a sampling site. A water-quality and habitat conditions score was negatively correlated with the percent of urban land in a 1-kilometer radial buffer of the sampling site (rho (r) = -0.86; p < 0.001), the percent of impervious surface (r = -0.70; p < 0.05), and the percent of urban land in the watershed (r = -0.67; p < 0.05). A biological condition score also was negatively correlated with the percent of urban land in a 1-kilometer radial buffer of the sampling site (r = -0.95; p < 0.0001), the percent of impervious surface (r = -0.75; p < 0.05), and the percent of urban land in the watershed (r = -0.79; p < 0.01). The percent of urban land in a 25-meter stream buffer along the stream corridor also had negative correlations with a water-quality and habitat conditions score (r = -0.80; p < 0.01) and a biological condition score (r = -0.86; p < 0.01). Mean Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa richness showed a response to urbanization in a watershed, indicating that EPT taxa richness may be an appropriate metric to evaluate the effects of urban land use on small streams in this region. Results from this study indicate that the percent of urban land use in buffer zones and the percent of impervious surface in a watershed can be used as indicators of stream quality.

Impacts of land use and land cover on surface and air temperature in urban landscapes

NASA Astrophysics Data System (ADS)

Crum, S.; Jenerette, D.

2015-12-01

Accelerating urbanization affects regional climate as the result of changing land cover and land use (LCLU). Urban land cover composition may provide valuable insight into relationships among urbanization, air, and land-surface temperature (Ta and LST, respectively). Climate may alter these relationships, where hotter climates experience larger LULC effects. To address these hypotheses we examined links between Ta, LST, LCLU, and vegetation across an urban coastal to desert climate gradient in southern California, USA. Using surface temperature radiometers, continuously measuring LST on standardized asphalt, concrete, and turf grass surfaces across the climate gradient, we found a 7.2°C and 4.6°C temperature decrease from asphalt to vegetated cover in the coast and desert, respectively. There is 131% more temporal variation in asphalt than turf grass surfaces, but 37% less temporal variation in concrete than turf grass. For concrete and turf grass surfaces, temporal variation in temperature increased from coast to desert. Using ground-based thermal imagery, measuring LST for 24 h sequences over citrus orchard and industrial use locations, we found a 14.5°C temperature decrease from industrial to orchard land use types (38.4°C and 23.9°C, respectively). Additionally, industrial land use types have 209% more spatial variation than orchard (CV=0.20 and 0.09, respectively). Using a network of 300 Ta (iButton) sensors mounted in city street trees throughout the region and hyperspectral imagery data we found urban vegetation greenness, measured using the normalized difference vegetation index (NDVI), was negatively correlated to Ta at night across the climate gradient. Contrasting previous findings, the closest coupling between NDVI and Ta is at the coast from 0000 h to 0800 h (highest r2 = 0.6, P < 0.05) while relationships at the desert are weaker (highest r2 = 0.38, P < 0.05). These findings indicate that vegetation cover in urbanized regions of southern California, USA decrease Ta and LST and spatial variation in LST, while built surfaces and land uses have the opposite effect. Furthermore these relationships are regulated by regional climate patterns, with decreases in Ta and LST being strongest in the coastal sub-region.

Impact of land cover data on the simulation of urban heat island for Berlin using WRF coupled with bulk approach of Noah-LSM

NASA Astrophysics Data System (ADS)

Li, Huidong; Wolter, Michael; Wang, Xun; Sodoudi, Sahar

2017-09-01

Urban-rural difference of land cover is the key determinant of urban heat island (UHI). In order to evaluate the impact of land cover data on the simulation of UHI, a comparative study between up-to-date CORINE land cover (CLC) and Urban Atlas (UA) with fine resolution (100 and 10 m) and old US Geological Survey (USGS) data with coarse resolution (30 s) was conducted using the Weather Research and Forecasting model (WRF) coupled with bulk approach of Noah-LSM for Berlin. The comparison between old data and new data partly reveals the effect of urbanization on UHI and the historical evolution of UHI, while the comparison between different resolution data reveals the impact of resolution of land cover on the simulation of UHI. Given the high heterogeneity of urban surface and the fine-resolution land cover data, the mosaic approach was implemented in this study to calculate the sub-grid variability in land cover compositions. Results showed that the simulations using UA and CLC data perform better than that using USGS data for both air and land surface temperatures. USGS-based simulation underestimates the temperature, especially in rural areas. The longitudinal variations of both temperature and land surface temperature show good agreement with urban fraction for all the three simulations. To better study the comprehensive characteristic of UHI over Berlin, the UHI curves (UHIC) are developed for all the three simulations based on the relationship between temperature and urban fraction. CLC- and UA-based simulations show smoother UHICs than USGS-based simulation. The simulation with old USGS data obviously underestimates the extent of UHI, while the up-to-date CLC and UA data better reflect the real urbanization and simulate the spatial distribution of UHI more accurately. However, the intensity of UHI simulated by CLC and UA data is not higher than that simulated by USGS data. The simulated air temperature is not dominated by the land cover as much as the land surface temperature, as air temperature is also affected by air advection.

Numerical Study of the Effect of Urbanization on the Climate of Desert Cities

NASA Astrophysics Data System (ADS)

Kamal, Samy

This study uses the Weather Research and Forecasting (WRF) model to simulate and predict the changes in local climate attributed to the urbanization for five desert cities. The simulations are performed in the fashion of climate downscaling, constrained by the surface boundary conditions generated from high resolution land-use maps. For each city, the land-use maps of 1985 and 2010 from Landsat satellite observation, and a projected land-use map for 2030, are used to represent the past, present, and future. An additional set of simulations for Las Vegas, the largest of the five cities, uses the NLCD 1992 and 2006 land-use maps and an idealized historical land-use map with no urban coverage for 1900. The study finds that urbanization in Las Vegas produces a classic urban heat island (UHI) at night but a minor cooling during the day. A further analysis of the surface energy balance shows that the decrease in surface Albedo and increase effective emissivity play an important role in shaping the local climate change over urban areas. The emerging urban structures slow down the diurnal wind circulation over the city due to an increased effective surface roughness. This leads to a secondary modification of temperature due to the interaction between the mechanical and thermodynamic effects of urbanization. The simulations for the five desert cities for 1985 and 2010 further confirm a common pattern of the climatic effect of urbanization with significant nighttime warming and moderate daytime cooling. This effect is confined to the urban area and is not sensitive to the size of the city or the detail of land cover in the surrounding areas. The pattern of nighttime warming and daytime cooling remains robust in the simulations for the future climate of the five cities using the projected 2030 land-use maps. Inter-city differences among the five urban areas are discussed.

Albedo, Land Cover, and Daytime Surface Temperature Variation Across an Urbanized Landscape

NASA Astrophysics Data System (ADS)

Trlica, A.; Hutyra, L. R.; Schaaf, C. L.; Erb, A.; Wang, J. A.

2017-11-01

Land surface albedo is a key parameter controlling the local energy budget, and altering the albedo of built surfaces has been proposed as a tool to mitigate high near-surface temperatures in the urban heat island. However, most research on albedo in urban landscapes has used coarse-resolution data, and few studies have attempted to relate albedo to other urban land cover characteristics. This study provides an empirical description of urban summertime albedo using 30 m remote sensing measurements in the metropolitan area around Boston, Massachusetts, relating albedo to metrics of impervious cover fraction, tree canopy coverage, population density, and land surface temperature (LST). At 30 m spatial resolution, median albedo over the study area (excluding open water) was 0.152 (0.112-0.187). Trends of lower albedo with increasing urbanization metrics and temperature emerged only after aggregating data to 500 m or the boundaries of individual towns, at which scale a -0.01 change in albedo was associated with a 29 (25-35)% decrease in canopy cover, a 27 (24-30)% increase in impervious cover, and an increase in population from 11 to 386 km-2. The most intensively urbanized towns in the region showed albedo up to 0.035 lower than the least urbanized towns, and mean mid-morning LST 12.6°C higher. Trends in albedo derived from 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) measurements were comparable, but indicated a strong contribution of open water at this coarser resolution. These results reveal linkages between albedo and urban land cover character, and offer empirical context for climate resilient planning and future landscape functional changes with urbanization.

Destruction of the recreational, asthetic, agricultural, wildlife conservation and preservation, and residential uses of the land as a result of the abuses of the manufacturing, commercial, extractive, construction, and transportation industries

NASA Technical Reports Server (NTRS)

1975-01-01

Explicit concern over land use and abuse stems from the recognition of the negative impacts of unrestrained and unregulated economic, industrial, and population growth upon finite land resources. Only one quarter of the total surface area of the earth is land, and of that a large portion is uninhabitable. The present stresses upon the land include urbanization, urban sprawl and urban congestion; electrical, nuclear industrial park siting requirements; land degradation through stripping surface minerals; land degradation through disposal of radioactive wastes, sewage sludge, solid waste and other industrial wastes; rising demand for agricultural land; and the erosion and destruction of land through elimination of protective coverings such as forests, grasslands, and wetlands.

Impact of Urban Growth on Surface Climate: A Case Study in Oran, Algeria

NASA Technical Reports Server (NTRS)

Bounoua, Lahouari; Safia, Abdelmounaine; Masek, Jeffrey; Peters-Lidars, Christaq; Imhoff, Marc L.

2008-01-01

We develop a land use map discriminating urban surfaces from other cover types over a semiarid region in North Africa and use it in a land surface model to assess the impact of urbanized land on surface energy, water and carbon balances. Unlike in temperate climates where urbanization creates a marked heat island effect, this effect is not strongly marked in semiarid regions. During summer, the urban class results in an additional warming of 1.45 C during daytime and 0.81 C at night compared to that simulated for needleleaf trees under similar climate conditions. Seasonal temperatures show urban areas warmer than their surrounding during summer and slightly cooler in winter. The hydrological cycle is practically "shut down" during summer and characterized by relatively large amount of runoff in winter. We estimate the annual amount of carbon uptake to 1.94 million metric tons with only 11.9% assimilated during the rainy season. However, if urbanization expands to reach 50% of the total area excluding forests, the annual total carbon uptake will decline by 35% and the July mean temperature would increase only 0.10 C, compared to current situation. In contrast, if urbanization expands to 50% of the total land excluding forests and croplands but all short vegetation is replaced by native broadleaf deciduous trees, the annual carbon uptake would increase 39% and the July mean temperature would decrease by 0.9 C, compared to current configuration. These results provide guidelines for urban planners and land use managers and indicate possibilities for mitigating the urban heat.

Urban Wetlands for Stormwater Control and Wildlife Enhancement.

ERIC Educational Resources Information Center

Adams, Lowell W.; Dove, Louise E.

Underdeveloped land absorbs much of the water which falls during a rainstorm. However, urban development (which results in much of the land being covered by buildings and pavement) increases the extent of impervious land surface over pre-development conditions. This results in greater post-development runoff of the urban stormwater. Urban…

Remote Sensing of Urban Thermal Landscape Characteristics and Their Affects on Local and Regional Meteorology and Air Quality: An Overview of NASA EOS-IDS Project Atlanta

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G., Jr.

1999-01-01

As an entity, the city is a manifestation of human "management" of the land. The act of city-building, however, drastically alters the biophysical environment, which ultimately, impacts local and regional land-atmosphere energy exchange processes. Because of the complexity of both the urban landscape and the attendant energy fluxes that result from urbanization, remote sensing offers the only real way to synoptically quantify these processes. One of the more important land-atmosphere fluxes that occurs over cities relates to the way that thermal energy is partitioned across the heterogeneous urban landscape. The individual land cover and surface material types that comprise the city, such as pavements and buildings, each have their own thermal energy regimes. As the collective urban landscape, the individual thermal energy responses from specific surfaces come together to form the urban heat island phenomena, which prevails as a dome of elevated air temperatures over cities. Although the urban heat island has been known to exist for well over 150 years, it is not understood how differences in thermal energy responses for land covers across the city interact to produce this phenomenon, or how the variability in thermal energy responses from different surface types drive its development. Additionally, it can be hypothesized that as cities grow in size through time, so do their urban heat islands. The interrelationships between urban sprawl and the respective growth of the urban heat island, however, have not been investigated. Moreover, little is known of the consequential effects of urban growth, land cover change, and the urban heat island as they impact local and regional meteorology and air quality.

The managed clearing: An overlooked land-cover type in urbanizing regions?

PubMed Central

Madden, Marguerite; Gray, Josh; Meentemeyer, Ross K.

2018-01-01

Urban ecosystem assessments increasingly rely on widely available map products, such as the U.S. Geological Service (USGS) National Land Cover Database (NLCD), and datasets that use generic classification schemes to detect and model large-scale impacts of land-cover change. However, utilizing existing map products or schemes without identifying relevant urban class types such as semi-natural, yet managed land areas that account for differences in ecological functions due to their pervious surfaces may severely constrain assessments. To address this gap, we introduce the managed clearings land-cover type–semi-natural, vegetated land surfaces with varying degrees of management practices–for urbanizing landscapes. We explore the extent to which managed clearings are common and spatially distributed in three rapidly urbanizing areas of the Charlanta megaregion, USA. We visually interpreted and mapped fine-scale land cover with special attention to managed clearings using 2012 U.S. Department of Agriculture (USDA) National Agriculture Imagery Program (NAIP) images within 150 randomly selected 1-km2 blocks in the cities of Atlanta, Charlotte, and Raleigh, and compared our maps with National Land Cover Database (NLCD) data. We estimated the abundance of managed clearings relative to other land use and land cover types, and the proportion of land-cover types in the NLCD that are similar to managed clearings. Our study reveals that managed clearings are the most common land cover type in these cities, covering 28% of the total sampled land area– 6.2% higher than the total area of impervious surfaces. Managed clearings, when combined with forest cover, constitutes 69% of pervious surfaces in the sampled region. We observed variability in area estimates of managed clearings between the NAIP-derived and NLCD data. This suggests using high-resolution remote sensing imagery (e.g., NAIP) instead of modifying NLCD data for improved representation of spatial heterogeneity and mapping of managed clearings in urbanizing landscapes. Our findings also demonstrate the need to more carefully consider managed clearings and their critical ecological functions in landscape- to regional-scale studies of urbanizing ecosystems. PMID:29432442

The managed clearing: An overlooked land-cover type in urbanizing regions?

PubMed

Singh, Kunwar K; Madden, Marguerite; Gray, Josh; Meentemeyer, Ross K

2018-01-01

Urban ecosystem assessments increasingly rely on widely available map products, such as the U.S. Geological Service (USGS) National Land Cover Database (NLCD), and datasets that use generic classification schemes to detect and model large-scale impacts of land-cover change. However, utilizing existing map products or schemes without identifying relevant urban class types such as semi-natural, yet managed land areas that account for differences in ecological functions due to their pervious surfaces may severely constrain assessments. To address this gap, we introduce the managed clearings land-cover type-semi-natural, vegetated land surfaces with varying degrees of management practices-for urbanizing landscapes. We explore the extent to which managed clearings are common and spatially distributed in three rapidly urbanizing areas of the Charlanta megaregion, USA. We visually interpreted and mapped fine-scale land cover with special attention to managed clearings using 2012 U.S. Department of Agriculture (USDA) National Agriculture Imagery Program (NAIP) images within 150 randomly selected 1-km2 blocks in the cities of Atlanta, Charlotte, and Raleigh, and compared our maps with National Land Cover Database (NLCD) data. We estimated the abundance of managed clearings relative to other land use and land cover types, and the proportion of land-cover types in the NLCD that are similar to managed clearings. Our study reveals that managed clearings are the most common land cover type in these cities, covering 28% of the total sampled land area- 6.2% higher than the total area of impervious surfaces. Managed clearings, when combined with forest cover, constitutes 69% of pervious surfaces in the sampled region. We observed variability in area estimates of managed clearings between the NAIP-derived and NLCD data. This suggests using high-resolution remote sensing imagery (e.g., NAIP) instead of modifying NLCD data for improved representation of spatial heterogeneity and mapping of managed clearings in urbanizing landscapes. Our findings also demonstrate the need to more carefully consider managed clearings and their critical ecological functions in landscape- to regional-scale studies of urbanizing ecosystems.

Updating the 2001 National Land Cover Database Impervious Surface Products to 2006 using Landsat imagery change detection methods

USGS Publications Warehouse

Xian, George; Homer, Collin G.

2010-01-01

A prototype method was developed to update the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001 to a nominal date of 2006. NLCD 2001 is widely used as a baseline for national land cover and impervious cover conditions. To enable the updating of this database in an optimal manner, methods are designed to be accomplished by individual Landsat scene. Using conservative change thresholds based on land cover classes, areas of change and no-change were segregated from change vectors calculated from normalized Landsat scenes from 2001 and 2006. By sampling from NLCD 2001 impervious surface in unchanged areas, impervious surface predictions were estimated for changed areas within an urban extent defined by a companion land cover classification. Methods were developed and tested for national application across six study sites containing a variety of urban impervious surface. Results show the vast majority of impervious surface change associated with urban development was captured, with overall RMSE from 6.86 to 13.12% for these areas. Changes of urban development density were also evaluated by characterizing the categories of change by percentile for impervious surface. This prototype method provides a relatively low cost, flexible approach to generate updated impervious surface using NLCD 2001 as the baseline.

Efficiently modelling urban heat storage: an interface conduction scheme in an urban land surface model (aTEB v2.0)

NASA Astrophysics Data System (ADS)

Lipson, Mathew J.; Hart, Melissa A.; Thatcher, Marcus

2017-03-01

Intercomparison studies of models simulating the partitioning of energy over urban land surfaces have shown that the heat storage term is often poorly represented. In this study, two implicit discrete schemes representing heat conduction through urban materials are compared. We show that a well-established method of representing conduction systematically underestimates the magnitude of heat storage compared with exact solutions of one-dimensional heat transfer. We propose an alternative method of similar complexity that is better able to match exact solutions at typically employed resolutions. The proposed interface conduction scheme is implemented in an urban land surface model and its impact assessed over a 15-month observation period for a site in Melbourne, Australia, resulting in improved overall model performance for a variety of common material parameter choices and aerodynamic heat transfer parameterisations. The proposed scheme has the potential to benefit land surface models where computational constraints require a high level of discretisation in time and space, for example at neighbourhood/city scales, and where realistic material properties are preferred, for example in studies investigating impacts of urban planning changes.

Recent land cover history and nutrient retention in riparian wetlands

USGS Publications Warehouse

Hogan, D.M.; Walbridge, M.R.

2009-01-01

Wetland ecosystems are profoundly affected by altered nutrient and sediment loads received from anthropogenic activity in their surrounding watersheds. Our objective was to compare a gradient of agricultural and urban land cover history during the period from 1949 to 1997, with plant and soil nutrient concentrations in, and sediment deposition to, riparian wetlands in a rapidly urbanizing landscape. We observed that recent agricultural land cover was associated with increases in Nitrogen (N) and Phosphorus (P) concentrations in a native wetland plant species. Conversely, recent urban land cover appeared to alter receiving wetland environmental conditions by increasing the relative availability of P versus N, as reflected in an invasive, but not a native, plant species. In addition, increases in surface soil Fe content suggests recent inputs of terrestrial sediments associated specifically with increasing urban land cover. The observed correlation between urban land cover and riparian wetland plant tissue and surface soil nutrient concentrations and sediment deposition, suggest that urbanization specifically enhances the suitability of riparian wetland habitats for the invasive species Japanese stiltgrass [Microstegium vimenium (Trinius) A. Camus]. ?? 2009 Springer Science+Business Media, LLC.

The impact of urbanization during half a century on surface meteorology based on WRF model simulations over National Capital Region, India

NASA Astrophysics Data System (ADS)

Sati, Ankur Prabhat; Mohan, Manju

2017-10-01

An estimated 50% of the global population lives in the urban areas, and this percentage is projected to reach around 69% by the year 2050 (World Urbanization Prospects 2009). There is a considerable growth of urban and built-up area during the recent decades over National Capital Region (NCR) of India (17-fold increase in the urban extent). The proposed study estimates the land use land cover changes particularly changes to urban class from other land use types such as croplands, shrubland, open areas, and water bodies and quantify these changes for a span of about five decades. Further, the impact of these land use/land cover changes is examined on spatial and temporal variations of meteorological parameters using the Weather Research and Forecast (WRF) Model. The urbanized areas appear to be one of the regions with highest changes in the values of the fluxes and temperatures where during daytime, the surface sensible heat flux values show a noticeable increase of 60-70 W m-2 which commensurate with increase in urbanization. Similarly, the nighttime LST and T2m show an increase of 3-5 and 2-3 K, respectively. The diurnal temperature range (DTR) of LST and surface temperature also shows a decrease of about 5 and 2-3 K, respectively, with increasing urbanization. Significant decrease in the magnitude of surface winds and relative humidity is also observed over the areas converted to urban form over a period of half a century. The impacts shown here have serious implications on human health, energy consumption, ventilation, and atmospheric pollution.

URBAN/SUBURBAN WATERSHED CHARACTERIZATION

EPA Science Inventory

The ability to characterize the land surface and related pollutant source loadings is critical for reliable watershed modeling. Urban/suburban land uses are the most rapidly growing land use class, generating non-point source pollutant loadings likely to seriously impair streams...

Multi-Temporal Multi-Sensor Analysis of Urbanization and Environmental/Climate Impact in China for Sustainable Urban Development

NASA Astrophysics Data System (ADS)

Ban, Yifang; Gong, Peng; Gamba, Paolo; Taubenbock, Hannes; Du, Peijun

2016-08-01

The overall objective of this research is to investigate multi-temporal, multi-scale, multi-sensor satellite data for analysis of urbanization and environmental/climate impact in China to support sustainable planning. Multi- temporal multi-scale SAR and optical data have been evaluated for urban information extraction using innovative methods and algorithms, including KTH- Pavia Urban Extractor, Pavia UEXT, and an "exclusion- inclusion" framework for urban extent extraction, and KTH-SEG, a novel object-based classification method for detailed urban land cover mapping. Various pixel- based and object-based change detection algorithms were also developed to extract urban changes. Several Chinese cities including Beijing, Shanghai and Guangzhou are selected as study areas. Spatio-temporal urbanization patterns and environmental impact at regional, metropolitan and city core were evaluated through ecosystem service, landscape metrics, spatial indices, and/or their combinations. The relationship between land surface temperature and land-cover classes was also analyzed.The urban extraction results showed that urban areas and small towns could be well extracted using multitemporal SAR data with the KTH-Pavia Urban Extractor and UEXT. The fusion of SAR data at multiple scales from multiple sensors was proven to improve urban extraction. For urban land cover mapping, the results show that the fusion of multitemporal SAR and optical data could produce detailed land cover maps with improved accuracy than that of SAR or optical data alone. Pixel-based and object-based change detection algorithms developed with the project were effective to extract urban changes. Comparing the urban land cover results from mulitemporal multisensor data, the environmental impact analysis indicates major losses for food supply, noise reduction, runoff mitigation, waste treatment and global climate regulation services through landscape structural changes in terms of decreases in service area, edge contamination and fragmentation. In terms ofclimate impact, the results indicate that land surface temperature can be related to land use/land cover classes.

Determination of the Impact of Urbanization on Agricultural Lands using Multi-temporal Satellite Sensor Images

NASA Astrophysics Data System (ADS)

Kaya, S.; Alganci, U.; Sertel, E.; Ustundag, B.

2015-12-01

Throughout the history, agricultural activities have been performed close to urban areas. Main reason behind this phenomenon is the need of fast marketing of the agricultural production to urban residents and financial provision. Thus, using the areas nearby cities for agricultural activities brings out advantage of easy transportation of productions and fast marketing. For decades, heavy migration to cities has directly and negatively affected natural grasslands, forests and agricultural lands. This pressure has caused agricultural lands to be changed into urban areas. Dense urbanization causes increase in impervious surfaces, heat islands and many other problems in addition to destruction of agricultural lands. Considering the negative impacts of urbanization on agricultural lands and natural resources, a periodic monitoring of these changes becomes indisputably important. At this point, satellite images are known to be good data sources for land cover / use change monitoring with their fast data acquisition, large area coverages and temporal resolution properties. Classification of the satellite images provides thematic the land cover / use maps of the earth surface and changes can be determined with GIS based analysis multi-temporal maps. In this study, effects of heavy urbanization over agricultural lands in Istanbul, metropolitan city of Turkey, were investigated with use of multi-temporal Landsat TM satellite images acquired between 1984 and 2011. Images were geometrically registered to each other and classified using supervised maximum likelihood classification algorithm. Resulting thematic maps were exported to GIS environment and destructed agricultural lands by urbanization were determined using spatial analysis.

Albedo and its Relationship to Land Cover and the Urban Heat Island in the Boston Metropolitan Region

NASA Astrophysics Data System (ADS)

Trlica, A.; Hutyra, L.; Wang, J.; Schaaf, C.; Erb, A.

2016-12-01

The urban built environment creates key changes in the biophysical character of the landscape, including the creation of Urban Heat Islands (UHIs) with increased near-surface temperatures in and around cities. Alteration in surface albedo is believed to partially drive UHIs through greater absorption of solar energy, but few empirical studies have specifically quantified albedo across a heterogeneous urban landscape, or investigated linkages between albedo, the UHI, and other surface socio-biophysical characteristics at a high enough spatial resolution to discern urban-scale features. This study used data derived from observations by Landsat and other remote sensing platforms to measure albedo across a varied urban landscape centered on Boston, Massachusetts, and examined the relationship between albedo, several key indicators of urban surface character (canopy cover, impervious fraction, and population density) and land surface temperature at resolutions of both 30 and 500 m. Albedo tended to be lower in areas with highest urbanization intensity indicators compared to rural undeveloped areas, and areas with lower albedo tended also to have higher median daytime summer surface temperatures. A k-means classification utilizing all the data available for each pixel revealed several distinct patterns of urban land cover corresponding mainly to the density of population and constructed surfaces and their impact on tree canopy cover. Mean 30-m summer surface temperatures ranged from 40.0 °C (SD = 2.6) in urban core areas to 26.2 °C (SD = 1.1) in nearby forest, but we only observed correspondingly large albedo decreases in the highest density urban core, with mean albedo of 0.116 (SD = 0.015) compared with 0.155 (SD = 0.015) in forest. Observations show that lower albedo in the Boston metropolitan region may be an important component of the local UHI in the most densely built-up urban core regions, while the UHI temperature effect in less densely settled peripheral regions is more likely to be driven primarily by reduced evapotranspiration due to diminished tree canopy and greater impervious surface coverage. These results empirically characterize surface albedo across a suite of land cover categories and biophysical characteristics and reveal how albedo relates to surface temperatures in this urbanized region.

Project ATLANTA (Atlanta Land use Analysis: Temperature and Air Quality): Use of Remote Sensing and Modeling to Analyze How Urban Land Use Change Affects Meteorology and Air Quality Through Time

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G., Jr.

1999-01-01

This paper presents an overview of Project ATLANTA (ATlanta Land use ANalysis: Temperature and Air-quality) which is an investigation that seeks to observe, measure, model, and analyze how the rapid growth of the Atlanta, Georgia metropolitan area since the early 1970's has impacted the region's climate and air quality. The primary objectives for this research effort are: (1) To investigate and model the relationships between land cover change in the Atlanta metropolitan, and the development of the urban heat island phenomenon through time; (2) To investigate and model the temporal relationships between Atlanta urban growth and land cover change on air quality; and (3) To model the overall effects of urban development on surface energy budget characteristics across the Atlanta urban landscape through time. Our key goal is to derive a better scientific understanding of how land cover changes associated with urbanization in the Atlanta area, principally in transforming forest lands to urban land covers through time, has, and will, effect local and regional climate, surface energy flux, and air quality characteristics. Allied with this goal is the prospect that the results from this research can be applied by urban planners, environmental managers and other decision-makers, for determining how urbanization has impacted the climate and overall environment of the Atlanta area. Multiscaled remote sensing data, particularly high resolution thermal infrared data, are integral to this study for the analysis of thermal energy fluxes across the Atlanta urban landscape.

Modeling the Warming Impact of Urban Land Expansion on Hot Weather Using the Weather Research and Forecasting Model: A Case Study of Beijing, China

NASA Astrophysics Data System (ADS)

Liu, Xiaojuan; Tian, Guangjin; Feng, Jinming; Ma, Bingran; Wang, Jun; Kong, Lingqiang

2018-06-01

The impacts of three periods of urban land expansion during 1990-2010 on near-surface air temperature in summer in Beijing were simulated in this study, and then the interrelation between heat waves and urban warming was assessed. We ran the sensitivity tests using the mesoscaleWeather Research and Forecasting model coupled with a single urban canopy model, as well as high-resolution land cover data. The warming area expanded approximately at the same scale as the urban land expansion. The average regional warming induced by urban expansion increased but the warming speed declined slightly during 2000-2010. The smallest warming occurred at noon and then increased gradually in the afternoon before peaking at around 2000 LST—the time of sunset. In the daytime, urban warming was primarily caused by the decrease in latent heat flux at the urban surface. Urbanization led to more ground heat flux during the day and then more release at night, which resulted in nocturnal warming. Urban warming at night was higher than that in the day, although the nighttime increment in sensible heat flux was smaller. This was because the shallower planetary boundary layer at night reduced the release efficiency of near-surface heat. The simulated results also suggested that heat waves or high temperature weather enhanced urban warming intensity at night. Heat waves caused more heat to be stored in the surface during the day, greater heat released at night, and thus higher nighttime warming. Our results demonstrate a positive feedback effect between urban warming and heat waves in urban areas.

Using Landsat Thematic Mapper (TM) sensor to detect change in land surface temperature in relation to land use change in Yazd, Iran

NASA Astrophysics Data System (ADS)

Zareie, Sajad; Khosravi, Hassan; Nasiri, Abouzar; Dastorani, Mostafa

2016-11-01

Land surface temperature (LST) is one of the key parameters in the physics of land surface processes from local to global scales, and it is one of the indicators of environmental quality. Evaluation of the surface temperature distribution and its relation to existing land use types are very important to the investigation of the urban microclimate. In arid and semi-arid regions, understanding the role of land use changes in the formation of urban heat islands is necessary for urban planning to control or reduce surface temperature. The internal factors and environmental conditions of Yazd city have important roles in the formation of special thermal conditions in Iran. In this paper, we used the temperature-emissivity separation (TES) algorithm for LST retrieving from the TIRS (Thermal Infrared Sensor) data of the Landsat Thematic Mapper (TM). The root mean square error (RMSE) and coefficient of determination (R2) were used for validation of retrieved LST values. The RMSE of 0.9 and 0.87 °C and R2 of 0.98 and 0.99 were obtained for the 1998 and 2009 images, respectively. Land use types for the city of Yazd were identified and relationships between land use types, land surface temperature and normalized difference vegetation index (NDVI) were analyzed. The Kappa coefficient and overall accuracy were calculated for accuracy assessment of land use classification. The Kappa coefficient values are 0.96 and 0.95 and the overall accuracy values are 0.97 and 0.95 for the 1998 and 2009 classified images, respectively. The results showed an increase of 1.45 °C in the average surface temperature. The results of this study showed that optical and thermal remote sensing methodologies can be used to research urban environmental parameters. Finally, it was found that special thermal conditions in Yazd were formed by land use changes. Increasing the area of asphalt roads, residential, commercial and industrial land use types and decreasing the area of the parks, green spaces and fallow lands in Yazd caused a rise in surface temperature during the 11-year period.

The Use of Multi-Source Satellite and Geospatial Data to Study the Effect of Urbanization of Primary Productivity in the United States

NASA Technical Reports Server (NTRS)

Imhoff, M. L.; Tucker, C. J.; Lawrence, W. T.; Stutzer, D.; Rusin, Robert

2000-01-01

Data from two different satellites, a digital land cover map, and digital census data were analyzed and combined in a geographic information system to study the effect of urbanization on photosynthetic vegetation productivity in the United States. Results show that urbanization can have a measurable but variable impact on the primary productivity of the land surface. Annual productivity can be reduced by as much as 20 days in some areas, but in resource limited regions, photosynthetic production can be enhanced by human activity. Overall, urban development reduces the productivity of the land surface and those areas with the highest productivity are directly in the path of urban sprawl.

Temporal change and its spatial variety on land surface temperature and land use changes in the Red River Delta, Vietnam, using MODIS time-series imagery.

PubMed

Van Nguyen, On; Kawamura, Kensuke; Trong, Dung Phan; Gong, Zhe; Suwandana, Endan

2015-07-01

Temporal changes in the land surface temperature (LST) in urbanization areas are important for studying an urban heat island (UHI) and regional climate change. This study examined the LST trends under different land use categories in the Red River Delta, Vietnam, using the Moderate Resolution Imaging Spectroradiometer (MODIS) LST product (MOD11A2) and land cover type product (MCD12Q1) for 11 years (2002-2012). Smoothened time-series MODIS LST data were reconstructed by the Harmonic Analysis of Time Series (HANTS) algorithm. The reconstructed LST (maximum and minimum temperatures) was assessed using the hourly air temperature dataset in two land-based meteorological stations provided by the National Climatic Data Center (NCDC). Significant correlation was obtained between MODIS LST and the air temperature for the daytime (R (2) = 0.73, root mean square error [RMSE] = 1.66 °C) and night time (R (2) = 0.84, RMSE = 1.79 °C). Statistical analysis also showed that LST trends vary strongly depending on the land cover type. Forest, wetland, and cropland had a slight tendency to decline, whereas cropland and urban had sharper increases. In urbanized areas, these increasing trends are even more obvious. This is undeniable evidence of the negative impact of urbanization on a surface urban heat island (SUHI) and global warming.

Integrated remote sensing for multi-temporal analysis of urban land cover-climate interactions

NASA Astrophysics Data System (ADS)

Savastru, Dan M.; Zoran, Maria A.; Savastru, Roxana S.

2016-08-01

Climate change is considered to be the biggest environmental threat in the future in the South- Eastern part of Europe. In frame of predicted global warming, urban climate is an important issue in scientific research. Surface energy processes have an essential role in urban weather, climate and hydrosphere cycles, as well in urban heat redistribution. This paper investigated the influences of urban growth on thermal environment in relationship with other biophysical variables in Bucharest metropolitan area of Romania. Remote sensing data from Landsat TM/ETM+ and time series MODIS Terra/Aqua sensors have been used to assess urban land cover- climate interactions over period between 2000 and 2015 years. Vegetation abundances and percent impervious surfaces were derived by means of linear spectral mixture model, and a method for effectively enhancing impervious surface has been developed to accurately examine the urban growth. The land surface temperature (Ts), a key parameter for urban thermal characteristics analysis, was also analyzed in relation with the Normalized Difference Vegetation Index (NDVI) at city level. Based on these parameters, the urban growth, and urban heat island effect (UHI) and the relationships of Ts to other biophysical parameters have been analyzed. The correlation analyses revealed that, at the pixel-scale, Ts possessed a strong positive correlation with percent impervious surfaces and negative correlation with vegetation abundances at the regional scale, respectively. This analysis provided an integrated research scheme and the findings can be very useful for urban ecosystem modeling.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haase, Dagmar, E-mail: dagmar.haase@ufz.d

The amount of land consumption required for housing and transport severely conflicts with both the necessity and the legal obligation to maintain the ecological potential afforded by open spaces to meet the needs of current and future generations with regards to the protection of resources and climate change. Owing to an increasing intensity of soil use, soil conditions appear to have deteriorated in most city regions around the world, namely their filter and runoff regulating functions are impaired by land surfacing. As such soil functions depend on the soil's biophysical properties and the degree of imperviousness, the impact on themore » water balance caused by urban growth varies considerably. In response to the demand for sustainably secure urban water resources, it needs to be assessed exactly how land surfacing affects the functions concerned. Analysing and evaluating urban land use change on the long-term water balance should improve our understanding of the impact of urbanisation on the water household. Therefore, this paper analyses the impact of urban land use change and land surfacing on the long-term urban water balance over a 130-year trajectory by using simple model approaches that are based on data available to the public. The test site is the city of Leipzig. In particular, attention is to be paid to estimating changes of evapotranspiration, direct runoff and groundwater recharge.« less

Nested High Resolution Modeling of the Impact of Urbanization on Regional Climate in Three Vast Urban Agglomerations in China

NASA Astrophysics Data System (ADS)

Wang, Jun; Feng, Jinming; Yan, Zhongwei; Hu, Yonghong; Jia, Gensuo

2013-04-01

In this paper, the Weather Research and Forecasting (WRF) model coupled to the Urban Canopy Model (UCM) is employed to simulate the impact of urbanization on the regional climate over three vast city agglomerations in China. Based on high resolution land use and land cover data, two scenarios are designed to represent the non-urban and current urban land use distributions. By comparing the results of two nested, high resolution numerical experiments, the spatial and temporal changes on surface air temperature, heat stress index, surface energy budget and precipitation due to urbanization are analyzed and quantified. Urban expansion increases the surface air temperature in urban areas by about 1? and this climatic forcing of urbanization on temperature is more pronounced in summer and nighttime than other seasons and daytime. The heat stress intensity, which reflects the combined effects of temperature and humidity, is enhanced by about 0.5 units in urban areas. The regional incoming solar radiation increases after urban expansion, which may be caused by the reduction of cloud fraction. The increased temperature and roughness of the urban surface lead to enhanced convergence. Meanwhile, the planetary boundary layer is deepened and water vapor is mixed more evenly in the lower atmosphere. The deficit of water vapor leads to less convective available potential energy and more convective inhibition energy. Finally, these combined effects may reduce the rainfall amount over urban area mainly in summer and change the regional precipitation pattern to a certain extent.

A comparison between the effects of artificial land cover and anthropogenic heat on a localized heavy rain event in 2008 in Zoshigaya, Tokyo, Japan

NASA Astrophysics Data System (ADS)

Souma, Kazuyoshi; Tanaka, Kenji; Suetsugi, Tadashi; Sunada, Kengo; Tsuboki, Kazuhisa; Shinoda, Taro; Wang, Yuqing; Sakakibara, Atsushi; Hasegawa, Koichi; Moteki, Qoosaku; Nakakita, Eiichi

2013-10-01

5 August 2008, a localized heavy rainfall event caused a rapid increase in drainpipe discharge, which killed five people working in a drainpipe near Zoshigaya, Tokyo. This study compared the effects of artificial land cover and anthropogenic heat on this localized heavy rainfall event based on three ensemble experiments using a cloud-resolving model that includes realistic urban features. The first experiment CTRL (control) considered realistic land cover and urban features, including artificial land cover, anthropogenic heat, and urban geometry. In the second experiment NOAH (no anthropogenic heat), anthropogenic heat was ignored. In the third experiment NOLC (no land cover), urban heating from artificial land cover was reduced by keeping the urban geometry but with roofs, walls, and roads of artificial land cover replaced by shallow water. The results indicated that both anthropogenic heat and artificial land cover increased the amount of precipitation and that the effect of artificial land cover was larger than that of anthropogenic heat. However, in the middle stage of the precipitation event, the difference between the two effects became small. Weak surface heating in NOAH and NOLC reduced the near-surface air temperature and weakened the convergence of horizontal wind and updraft over the urban areas, resulting in a reduced rainfall amount compared with that in CTRL.

Exploring a new method for the retrieval of urban thermophysical properties using thermal infrared remote sensing and deterministic modeling

NASA Astrophysics Data System (ADS)

De Ridder, K.; Bertrand, C.; Casanova, G.; Lefebvre, W.

2012-09-01

Increasingly, mesoscale meteorological and climate models are used to predict urban weather and climate. Yet, large uncertainties remain regarding values of some urban surface properties. In particular, information concerning urban values for thermal roughness length and thermal admittance is scarce. In this paper, we present a method to estimate values for thermal admittance in combination with an optimal scheme for thermal roughness length, based on METEOSAT-8/SEVIRI thermal infrared imagery in conjunction with a deterministic atmospheric model containing a simple urbanized land surface scheme. Given the spatial resolution of the SEVIRI sensor, the resulting parameter values are applicable at scales of the order of 5 km. As a study case we focused on the city of Paris, for the day of 29 June 2006. Land surface temperature was calculated from SEVIRI thermal radiances using a new split-window algorithm specifically designed to handle urban conditions, as described inAppendix A, including a correction for anisotropy effects. Land surface temperature was also calculated in an ensemble of simulations carried out with the ARPS mesoscale atmospheric model, combining different thermal roughness length parameterizations with a range of thermal admittance values. Particular care was taken to spatially match the simulated land surface temperature with the SEVIRI field of view, using the so-called point spread function of the latter. Using Bayesian inference, the best agreement between simulated and observed land surface temperature was obtained for the Zilitinkevich (1970) and Brutsaert (1975) thermal roughness length parameterizations, the latter with the coefficients obtained by Kanda et al. (2007). The retrieved thermal admittance values associated with either thermal roughness parameterization were, respectively, 1843 ± 108 J m-2 s-1/2 K-1 and 1926 ± 115 J m-2 s-1/2 K-1.

Urban surface energy fluxes based on remotely-sensed data and micrometeorological measurements over the Kansai area, Japan

NASA Astrophysics Data System (ADS)

Sukeyasu, T.; Ueyama, M.; Ando, T.; Kosugi, Y.; Kominami, Y.

2017-12-01

The urban heat island is associated with land cover changes and increases in anthropogenic heat fluxes. Clear understanding of the surface energy budget at urban area is the most important for evaluating the urban heat island. In this study, we develop a model based on remotely-sensed data for the Kansai area in Japan and clarify temporal transitions and spatial distributions of the surface energy flux from 2000 to 2016. The model calculated the surface energy fluxes based on various satellite and GIS products. The model used land surface temperature, surface emissivity, air temperature, albedo, downward shortwave radiation and land cover/use type from the moderate resolution imaging spectroradiometer (MODIS) under cloud free skies from 2000 to 2016 over the Kansai area in Japan (34 to 35 ° N, 135 to 136 ° E). Net radiation was estimated by a radiation budget of upward/downward shortwave and longwave radiation. Sensible heat flux was estimated by a bulk aerodynamic method. Anthropogenic heat flux was estimated by the inventory data. Latent heat flux was examined with residues of the energy budget and parameterization of bulk transfer coefficients. We validated the model using observed fluxes from five eddy-covariance measurement sites: three urban sites and two forested sites. The estimated net radiation roughly agreed with the observations, but the sensible heat flux were underestimated. Based on the modeled spatial distributions of the fluxes, the daytime net radiation in the forested area was larger than those in the urban area, owing to higher albedo and land surface temperatures in the urban area than the forested area. The estimated anthropogenic heat flux was high in the summer and winter periods due to increases in energy-requirements.

Nested high-resolution modeling of the impact of urbanization on regional climate in three vast urban agglomerations in China

NASA Astrophysics Data System (ADS)

Wang, Jun; Feng, Jinming; Yan, Zhongwei; Hu, Yonghong; Jia, Gensuo

2012-11-01

In this paper, the Weather Research and Forecasting Model, coupled to the Urban Canopy Model, is employed to simulate the impact of urbanization on the regional climate over three vast city agglomerations in China. Based on high-resolution land use and land cover data, two scenarios are designed to represent the nonurban and current urban land use distributions. By comparing the results of two nested, high-resolution numerical experiments, the spatial and temporal changes on surface air temperature, heat stress index, surface energy budget, and precipitation due to urbanization are analyzed and quantified. Urban expansion increases the surface air temperature in urban areas by about 1°C, and this climatic forcing of urbanization on temperature is more pronounced in summer and nighttime than other seasons and daytime. The heat stress intensity, which reflects the combined effects of temperature and humidity, is enhanced by about 0.5 units in urban areas. The regional incoming solar radiation increases after urban expansion, which may be caused by the reduction of cloud fraction. The increased temperature and roughness of the urban surface lead to enhanced convergence. Meanwhile, the planetary boundary layer is deepened, and water vapor is mixed more evenly in the lower atmosphere. The deficit of water vapor leads to less convective available potential energy and more convective inhibition energy. Finally, these combined effects may reduce the rainfall amount over urban areas, mainly in summer, and change the regional precipitation pattern to a certain extent.

Does the spatial arrangement of vegetation and anthropogenic land cover features matter? Case studies of urban warming and cooling in Phoenix and Las Vegas

NASA Astrophysics Data System (ADS)

Myint, S. W.; Zheng, B.; Fan, C.; Kaplan, S.; Brazel, A.; Middel, A.; Smith, M.

2014-12-01

While the relationship between fractional cover of anthropogenic and vegetation features and the urban heat island has been well studied, the effect of spatial arrangements (e.g., clustered, dispersed) of these features on urban warming or cooling are not well understood. The goal of this study is to examine if and how spatial configuration of land cover features influence land surface temperatures (LST) in urban areas. This study focuses on Phoenix, AZ and Las Vegas, NV that have undergone dramatic urban expansion. The data used to classify detailed urban land cover types include Geoeye-1 (Las Vegas) and QuickBird (Phoenix). The Geoeye-1 image (3 m resolution) was acquired on October 12, 2011 and the QuickBird image (2.4 m resolution) was taken on May 29, 2007. Classification was performed using object based image analysis (OBIA). We employed a spatial autocorrelation approach (i.e., Moran's I) that measures the spatial dependence of a point to its neighboring points and describes how clustered or dispersed points are arranged in space. We used Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data acquired over Phoenix (daytime on June 10, 2011 and nighttime on October 17, 2011) and Las Vegas (daytime on July 6, 2005 and nighttime on August 27, 2005) to examine daytime and nighttime LST with regards to the spatial arrangement of anthropogenic and vegetation features. We spatially correlate Moran's I values of each land cover per surface temperature, and develop regression models. The spatial configuration of grass and trees shows strong negative correlations with LST, implying that clustered vegetation lowers surface temperatures more effectively. In contrast, a clustered spatial arrangement of anthropogenic land-cover features, especially impervious surfaces, significantly elevates surface temperatures. Results from this study suggest that the spatial configuration of anthropogenic and vegetation features influence urban warming and cooling.

Simulation of urban land surface temperature based on sub-pixel land cover in a coastal city

NASA Astrophysics Data System (ADS)

Zhao, Xiaofeng; Deng, Lei; Feng, Huihui; Zhao, Yanchuang

2014-11-01

The sub-pixel urban land cover has been proved to have obvious correlations with land surface temperature (LST). Yet these relationships have seldom been used to simulate LST. In this study we provided a new approach of urban LST simulation based on sub-pixel land cover modeling. Landsat TM/ETM+ images of Xiamen city, China on both the January of 2002 and 2007 were used to acquire land cover and then extract the transformation rule using logistic regression. The transformation possibility was taken as its percent in the same pixel after normalization. And cellular automata were used to acquire simulated sub-pixel land cover on 2007 and 2017. On the other hand, the correlations between retrieved LST and sub-pixel land cover achieved by spectral mixture analysis in 2002 were examined and a regression model was built. Then the regression model was used on simulated 2007 land cover to model the LST of 2007. Finally the LST of 2017 was simulated for urban planning and management. The results showed that our method is useful in LST simulation. Although the simulation accuracy is not quite satisfactory, it provides an important idea and a good start in the modeling of urban LST.

The effect of urban heat island on Izmir's city ecosystem and climate.

PubMed

Corumluoglu, Ozsen; Asri, Ibrahim

2015-03-01

Depending on the researches done on urban landscapes, it is found that the heat island intensity caused by the activities in any city has some impact on the ecosystem of the region and on the regional climate. Urban areas located in arid and semiarid lands somehow represent heat increase when it is compared with the heat in the surrounding rural areas. Thus, cities located amid forested and temperate climate regions show moderate temperatures. The impervious surfaces let the rainfall leave the city lands faster than undeveloped areas. This effect reduces water's cooling effects on these lands. More significantly, if trees and other vegetations are rare in any region, it means less evapotranspiration-the process by which trees "exhale" water. Trees also contribute to the cooling of urban lands by their shade. Land cover and land use maps can easily be produced by processing of remote sensing satellites' images, like processing of Landsat's images. As a result of this process, urban regions can be distinguished from vegetation. Analyzed GIS data produced and supported by these images can be utilized to determine the impact of urban land on energy, water, and carbon balances at the Earth's surface. Here in this study, it is found that remote sensing technique with thermal images is a liable technique to asses where urban heat islands and hot spots are located in cities. As an application area, in Izmir, it was found that the whole city was in high level of surface temperature as it was over 28 °C during the summer times. Beside this, the highest temperature values which go up to 47 °C are obtained at industrial regions especially where the iron-steel factories and the related industrial activities are.

Characterizing continuous urban growth using composited time-series Landsat data

NASA Astrophysics Data System (ADS)

Song, X. P.; Sexton, J. O.; Huang, C.; Feng, M.; Channan, S.; Baker, M. E.; Townshend, J. R.

2014-12-01

Impervious surfaces are land cover features through which water cannot penetrate into the soil. As an indicator of urban land use, impervious surface cover (ISC) is disproportionally important to human beings-although covering only 0.5% of the Earth's terrestrial surface, cities support over 50% the Earth's population. The increasing demand for built-up space by a growing urban population has been driving land use change in urban areas worldwide. An increase in ISC can significantly impact the biophysical characteristics of land surface, such as altering the local surface energy balance, or transforming regional hydrological systems. Remotely sensed data is commonly used as the primary data source for extracting impervious surface information for monitoring urban growth, but current studies often lack the sufficient temporal resolution or thematic detail to reveal the long-term, nonlinear development of impervious surfaces over time. In a previous study (Sexton et al. 2013), we created an annual stack of 30-m percent ISC estimates for the Washington DC-Baltimore metropolitan region from 1984 to 2010 by compositing all available Landsat images in the USGS archive. Here we developed a robust time-series method to detect impervious surface change. The method employs a customized logistic function for every pixel to model the continuous process of urban growth. It quantifies the fractional intensity of ISC change at the sub-pixel level and also characterizes the timing and length (in years) of urban development. The new method detects change based on a sequence of observations before, during and after change and thus is highly resistant to random noises. Our results showed that the DC-Baltimore metropolitan region experienced an accelerated growth pathway from the late 1980s to the late 2000s. The majority of urban and sub-urban development occurred at scales finer than the Landsat resolution (30 m), with a region-wide mean intensity of 46% ISC increase. Our study demonstrates the value of the long-term and fine temporal resolution data offered by the Landsat archive, and also highlights the possible limitations of Landsat's spatial resolution in characterizing continuous urban development.

Modeling Impact of Urbanization in US Cities Using Simple Biosphere Model SiB2

NASA Technical Reports Server (NTRS)

Zhang, Ping; Bounoua, Lahouari; Thome, Kurtis; Wolfe, Robert

2016-01-01

We combine Landsat- and the Moderate Resolution Imaging Spectroradiometer (MODIS)-based products, as well as climate drivers from Phase 2 of the North American Land Data Assimilation System (NLDAS-2) in a Simple Biosphere land surface model (SiB2) to assess the impact of urbanization in continental USA (excluding Alaska and Hawaii). More than 300 cities and their surrounding suburban and rural areas are defined in this study to characterize the impact of urbanization on surface climate including surface energy, carbon budget, and water balance. These analyses reveal an uneven impact of urbanization across the continent that should inform upon policy options for improving urban growth including heat mitigation and energy use, carbon sequestration and flood prevention.

Quantifying multi-temporal urban development characteristics in Las Vegas from Landsat and ASTER data

USGS Publications Warehouse

Xian, G.; Crane, M.; McMahon, C.

2008-01-01

Urban development has expanded rapidly in Las Vegas, Nevada of the United States, over the last fifty years. A major environmental change associated with this urbanization trend is the transformation of the landscape from natural cover types to increasingly anthropogenic impervious surface. This research utilizes remote sensing data from both the Landsat and Terra-Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instruments in conjunction with digital orthophotography to estimate urban extent and its temporal changes by determining sub-pixel impervious surfaces. Percent impervious surface area has shown encouraging agreement with urban land extent and development density. Results indicate that total urban land-use increases approximately 110 percent from 1984 to 2002. Most of the increases are associated with medium-to high-density urban development. Places having significant increases in impervious surfaces are in the northwestern and southeastern parts of Las Vegas. Most high-density urban development, however, appears in central Las Vegas. Impervious surface conditions for 2002 measured from Landsat and ASTER satellite data are compared in terms of their accuracy.

A numerical study of the effect of urbanization on the climate of Las Vegas metropolitan area

NASA Astrophysics Data System (ADS)

Kamal, S. M.; Huang, H. P.; Myint, S. W.

2014-12-01

Las Vegas is one of the fastest growing desert cities. Its developed area has doubled in the last 30 years. An accurate prediction of the effect of urbanization on the climate of the city is crucial for resource management and planning. In this study, we use the Weather Research and Forecasting (WRF) model coupled with a land surface and urban canopy model to investigate the effects of urbanization on the regional climate pattern around Las Vegas. High resolution numerical simulations are performed with a 3 km resolution over the metropolitan area. With identical lateral boundary conditions, three land-use land-cover maps, representing 2006, 1992 and hypothetical 1900, are used in multiple simulations. The differences in the simulated climate among those cases are used to quantify the urban effect. The simulated surface air temperature is validated against observational data from the weather station at the McCarran airport. It is found that urbanization affects substantial warming during the night but a minor cooling during the day. Detailed diagnostics of the surface energy budget are performed to help interpret this result. In addition, the emerging urban structures are found to have a mechanical effect of slowing down the climatological wind field over the urban area. The change in wind, in turn, leads to a secondary modification of the temperature structure within the air shed of the city. This finding suggests the need to combine the mechanical and thermodynamic effects to construct a complete picture of the influence of land cover on urban climate. In all cases of the simulations, it is also demonstrated that urbanization influences surface air temperature mainly within the metropolitan area.

Monitoring Urbanization-Related Land Cover Change on the U.S. Great Plains and Impacts on Remotely Sensed Vegetation Dynamics

NASA Astrophysics Data System (ADS)

Krehbiel, C. P.; Jackson, T.; Henebry, G. M.

2014-12-01

Earth is currently in an era of rapid urban growth with >50% of global population living in urban areas. Urbanization occurs alongside urban population growth, as cities expand to meet the demands of increasing population. Consequently, there is a need for remote sensing research to detect, monitor, and measure urbanization and its impacts on the biosphere. Here we used MODIS and Landsat data products to (1) detect urbanization-related land cover changes, (2) investigate urbanization-related impacts on land surface phenology (LSP) across rural to urban gradients and (3) explore fractional vegetation and impervious surface area regionally across the US Great Plains and within 14 cities in this region. We used the NLCD Percent Impervious Surface Area (%ISA) and Land Cover Type (LCT) products from 2001, 2006, and 2011 for 30m classification of the peri-urban environment. We investigated the impacts of urbanization-related land cover change on urban LSP at 30m resolution using the NDVI product from Web Enabled Landsat Data (http://weld.cr.usgs.gov) with accumulated growing degree-days calculated from first-order weather stations. We fitted convex quadratic LSP models to a decade (2003-2012) of observations to yield these phenometrics: modeled peak NDVI, time (thermal and calendar) to modeled peak, duration of season (DOS), and model fit. We compared our results to NDVI from MODIS NBAR (500m) and we explored the utility of 4 μm radiance (MODIS band 23) at 1 km resolution to characterize fractional vegetation dynamics in and around urbanized areas. Across all 14 cities we found increases in urbanized area (>25 %ISA) exceeding 10% from 2001-2011. Using LSP phenometrics, we were able to detect changes from cropland to suburban LCTs. In general we found negative relationships between DOS and distance from city center. We found a distinct seasonal cycle of MIR radiance over cropland LCTs due to the spectral contrast between bare soils and green vegetation.

Effects of climate and land cover on hydrology in the southeastern U.S.: Potential impacts on watershed planning

USGS Publications Warehouse

LaFontaine, Jacob H.; Hay, Lauren E.; Viger, Roland; Regan, R. Steve; Markstrom, Steven

2015-01-01

The hydrologic response to statistically downscaled general circulation model simulations of daily surface climate and land cover through 2099 was assessed for the Apalachicola-Chattahoochee-Flint River Basin located in the southeastern United States. Projections of climate, urbanization, vegetation, and surface-depression storage capacity were used as inputs to the Precipitation-Runoff Modeling System to simulate projected impacts on hydrologic response. Surface runoff substantially increased when land cover change was applied. However, once the surface depression storage was added to mitigate the land cover change and increases of surface runoff (due to urbanization), the groundwater flow component then increased. For hydrologic studies that include projections of land cover change (urbanization in particular), any analysis of runoff beyond the change in total runoff should include effects of stormwater management practices as these features affect flow timing and magnitude and may be useful in mitigating land cover change impacts on streamflow. Potential changes in water availability and how biota may respond to changes in flow regime in response to climate and land cover change may prove challenging for managers attempting to balance the needs of future development and the environment. However, these models are still useful for assessing the relative impacts of climate and land cover change and for evaluating tradeoffs when managing to mitigate different stressors.

Thermal signatures of urban land cover types: High-resolution thermal infrared remote sensing of urban heat island in Huntsville, AL

NASA Technical Reports Server (NTRS)

Lo, Chor Pang

1996-01-01

The main objective of this research is to apply airborne high-resolution thermal infrared imagery for urban heat island studies, using Huntsville, AL, a medium-sized American city, as the study area. The occurrence of urban heat islands represents human-induced urban/rural contrast, which is caused by deforestation and the replacement of the land surface by non-evaporating and non-porous materials such as asphalt and concrete. The result is reduced evapotranspiration and more rapid runoff of rain water. The urban landscape forms a canopy acting as a transitional zone between the atmosphere and the land surface. The composition and structure of this canopy have a significant impact on the thermal behavior of the urban environment. Research on the trends of surface temperature at rapidly growing urban sites in the United States during the last 30 to 50 years suggests that significant urban heat island effects have caused the temperatures at these sites to rise by 1 to 2 C. Urban heat islands have caused changes in urban precipitation and temperature that are at least similar to, if not greater than, those predicted to develop over the next 100 years by global change models. Satellite remote sensing, particularly NOAA AVHRR thermal data, has been used in the study of urban heat islands. Because of the low spatial resolution (1.1 km at nadir) of the AVHRR data, these studies can only examine and map the phenomenon at the macro-level. The present research provides the rare opportunity to utilize 5-meter thermal infrared data acquired from an airplane to characterize more accurately the thermal responses of different land cover types in the urban landscape as input to urban heat island studies.

Technical geothermal potential of urban subsurface influenced by land surface effects

NASA Astrophysics Data System (ADS)

Rivera, Jaime A.; Blum, Philipp; Bayer, Peter

2016-04-01

Changes in land use are probably one of the most notorious anthropogenic perturbations in urban environments. They significantly change the coupled thermal regime at the ground surface leading in most cases to increased ground surface temperatures (GST). The associated elevated vertical heat fluxes act at different scales and can influence the thermal conditions in several tens of meters in the subsurface. Urban subsurface thus often stores a higher amount of heat than less affected rural surroundings. The stored heat is regarded as a potential source of low-enthalpy geothermal energy to supply the heating energy demands in urban areas. In this work, we explore the technical geothermal potential of urban subsurface via ground coupled heat pumps with borehole heat exchangers (BHE). This is tackled by semi-analytical line-source equations. The commonly used response factors or g-functions are modified to include transient land surface effects. By including this additional source of heat, the new formulation allows to analyse the effect of pre-existing urban warming as well as different exploitation schemes fulfilling standard renewable and sustainable criteria. In our generalized reference scenario, it is demonstrated that energy gains for a single BHE may be up to 40 % when compared to non-urbanized conditions. For a scenario including the interaction of multiple BHEs, results indicate that it would be possible to supply between 6 % and 27 % of the heating demands in Central European urban settlements in a renewable way. The methodology is also applied to a study case of the city of Zurich, Switzerland, where the detailed evolution of land use is available.

Impact of Land Use/Land Cover Conditions on WRF Model Evaluation for Heat Island Assessment

NASA Astrophysics Data System (ADS)

Bhati, S.; Mohan, M.

2017-12-01

Urban heat island effect has been assessed using Weather Research and Forecasting model (WRF v3.5) focusing on air temperature and surface skin temperature in the sub-tropical urban Indian megacity of Delhi. Impact of urbanization related changes in land use/land cover (LULC) on model outputs has been analyzed. Four simulations have been carried out with different types of LULC data viz. (1) USGS , (2) MODIS, (3) user-modified USGS and (4) user modified land use data coupled with urban canopy model (UCM) for incorporation of canopy features. Heat island intensities have been estimated based on these simulations and subsequently compared with those derived from in-situ and satellite observations. There is a significant improvement in model performance with modification of LULC and inclusion of UCM. Overall, RMSEs for near surface temperature improved from 6.3°C to 3.9°C and index of agreement for mean urban heat island intensities (UHI) improved from 0.4 to 0.7 with modified land use coupled with UCM. In general, model is able to capture the magnitude of UHI as well as high UHI zones well. The study highlights the importance of appropriate and updated representation of landuse-landcover and urban canopies for improving predictive capabilities of the mesoscale models.

Model developments in TERRA_URB, the upcoming standard urban parametrization of the atmospheric numerical model COSMO(-CLM)

NASA Astrophysics Data System (ADS)

Wouters, Hendrik; Blahak, Ulrich; Helmert, Jürgen; Raschendorfer, Matthias; Demuzere, Matthias; Fay, Barbara; Trusilova, Kristina; Mironov, Dmitrii; Reinert, Daniel; Lüthi, Daniel; Machulskaya, Ekaterina

2015-04-01

In order to address urban climate at the regional scales, a new efficient urban land-surface parametrization TERRA_URB has been developed and coupled to the atmospheric numerical model COSMO-CLM. Hereby, several new advancements for urban land-surface models are introduced which are crucial for capturing the urban surface-energy balance and its seasonal dependency in the mid-latitudes. This includes a new PDF-based water-storage parametrization for impervious land, the representation of radiative absorption and emission by greenhouse gases in the infra-red spectrum in the urban canopy layer, and the inclusion of heat emission from human activity. TERRA_URB has been applied in offline urban-climate studies during European observation campaigns at Basel (BUBBLE), Toulouse (CAPITOUL), and Singapore, and currently applied in online studies for urban areas in Belgium, Germany, Switzerland, Helsinki, Singapore, and Melbourne. Because of its computational efficiency, high accuracy and its to-the-point conceptual easiness, TERRA_URB has been selected to become the standard urban parametrization of the atmospheric numerical model COSMO(-CLM). This allows for better weather forecasts for temperature and precipitation in cities with COSMO, and an improved assessment of urban outdoor hazards in the context of global climate change and urban expansion with COSMO-CLM. We propose additional extensions to TERRA_URB towards a more robust representation of cities over the world including their structural design. In a first step, COSMO's standard EXTernal PARarameter (EXTPAR) tool is updated for representing the cities into the land cover over the entire globe. Hereby, global datasets in the standard EXTPAR tool are used to retrieve the 'Paved' or 'sealed' surface Fraction (PF) referring to the presence of buildings and streets. Furthermore, new global data sets are incorporated in EXTPAR for describing the Anthropogenic Heat Flux (AHF) due to human activity, and optionally the Surface Area Index (SAI) derived from the Floor Space Index (FSI). In a second step, it is focussed on the urban/rural contrast in terms of turbulent transport in the surface layer by means of model sensivity experiments: On the theoretical basis of the TKE-based surface-layer transfer scheme of COSMO, we investigate the consistency between empirical functions for thermal roughness lengths and the urban/rural canopy morphology.

Synergistic use of optical and InSAR data for urban impervious surface mapping: A case study in Hong Kong

USGS Publications Warehouse

Jiang, L.; Liao, M.; Lin, H.; Yang, L.

2009-01-01

A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning and watershed resource management, require accurate and up‐to‐date geospatial data of urban impervious surfaces. In this study, the potential of the synergistic use of optical and InSAR data in urban impervious surface mapping at the sub‐pixel level was investigated. A case study in Hong Kong was conducted for this purpose by applying a classification and regression tree (CART) algorithm to SPOT 5 multispectral imagery and ERS‐2 SAR data. Validated by reference data derived from high‐resolution colour‐infrared (CIR) aerial photographs, our results show that the addition of InSAR feature information can improve the estimation of impervious surface percentage (ISP) in comparison with using SPOT imagery alone. The improvement is especially notable in separating urban impervious surface from the vacant land/bare ground, which has been a difficult task in ISP modelling with optical remote sensing data. In addition, the results demonstrate the potential to map urban impervious surface by using InSAR data alone. This allows frequent monitoring of world's cities located in cloud‐prone and rainy areas.

Understanding land use change impacts on microclimate using Weather Research and Forecasting (WRF) model

NASA Astrophysics Data System (ADS)

Li, Xia; Mitra, Chandana; Dong, Li; Yang, Qichun

2018-02-01

To explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under the urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. This study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.

Spatial regression models of park and land-use impacts on the urban heat island in central Beijing.

PubMed

Dai, Zhaoxin; Guldmann, Jean-Michel; Hu, Yunfeng

2018-06-01

Understanding the relationship between urban land structure and land surface temperatures (LST) is important for mitigating the urban heat island (UHI). This paper explores this relationship within central Beijing, an area located within the 2nd Ring Road. The urban variables include the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Build-up Index (NDBI), the area of building footprints, the area of main roads, the area of water bodies and a gravity index for parks that account for both park size and distance. The data are captured over 8 grids of square cells (30 m, 60 m, 90 m, 120 m, 150 m, 180 m, 210 m, 240 m). The research involves: (1) estimating land surface temperatures using Landsat 8 satellite imagery, (2) building the database of urban variables, and (3) conducting regression analyses. The results show that (1) all the variables impact surface temperatures, (2) spatial regressions are necessary to capture neighboring effects, and (3) higher-order polynomial functions are more suitable for capturing the effects of NDVI and NDBI. Copyright © 2018 Elsevier B.V. All rights reserved.

An approach for mapping large-area impervious surfaces: Synergistic use of Landsat-7 ETM+ and high spatial resolution imagery

USGS Publications Warehouse

Yang, Limin; Huang, Chengquan; Homer, Collin G.; Wylie, Bruce K.; Coan, Michael

2003-01-01

A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning, and resource management, require current and accurate geospatial data of urban impervious surfaces. We developed an approach to quantify urban impervious surfaces as a continuous variable by using multisensor and multisource datasets. Subpixel percent impervious surfaces at 30-m resolution were mapped using a regression tree model. The utility, practicality, and affordability of the proposed method for large-area imperviousness mapping were tested over three spatial scales (Sioux Falls, South Dakota, Richmond, Virginia, and the Chesapeake Bay areas of the United States). Average error of predicted versus actual percent impervious surface ranged from 8.8 to 11.4%, with correlation coefficients from 0.82 to 0.91. The approach is being implemented to map impervious surfaces for the entire United States as one of the major components of the circa 2000 national land cover database.

Urban land-cover change detection through sub-pixel imperviousness mapping using remotely sensed data

USGS Publications Warehouse

Yang, Limin; Xian, George Z.; Klaver, Jacqueline M.; Deal, Brian

2003-01-01

We developed a Sub-pixel Imperviousness Change Detection (SICD) approach to detect urban land-cover changes using Landsat and high-resolution imagery. The sub-pixel percent imperviousness was mapped for two dates (09 March 1993 and 11 March 2001) over western Georgia using a regression tree algorithm. The accuracy of the predicted imperviousness was reasonable based on a comparison using independent reference data. The average absolute error between predicted and reference data was 16.4 percent for 1993 and 15.3 percent for 2001. The correlation coefficient (r) was 0.73 for 1993 and 0.78 for 2001, respectively. Areas with a significant increase (greater than 20 percent) in impervious surface from 1993 to 2001 were mostly related to known land-cover/land-use changes that occurred in this area, suggesting that the spatial change of an impervious surface is a useful indicator for identifying spatial extent, intensity, and, potentially, type of urban land-cover/land-use changes. Compared to other pixel-based change-detection methods (band differencing, rationing, change vector, post-classification), information on changes in sub-pixel percent imperviousness allow users to quantify and interpret urban land-cover/land-use changes based on their own definition. Such information is considered complementary to products generated using other change-detection methods. In addition, the procedure for mapping imperviousness is objective and repeatable, hence, can be used for monitoring urban land-cover/land-use change over a large geographic area. Potential applications and limitations of the products developed through this study in urban environmental studies are also discussed.

Analyzing the effects of urban expansion on land surface temperature patterns by landscape metrics: a case study of Isfahan city, Iran.

PubMed

Madanian, Maliheh; Soffianian, Ali Reza; Koupai, Saeid Soltani; Pourmanafi, Saeid; Momeni, Mehdi

2018-03-03

Urban expansion can cause extensive changes in land use and land cover (LULC), leading to changes in temperature conditions. Land surface temperature (LST) is one of the key parameters that should be considered in the study of urban temperature conditions. The purpose of this study was, therefore, to investigate the effects of changes in LULC due to the expansion of the city of Isfahan on LST using landscape metrics. To this aim, two Landsat 5 and Landsat 8 images, which had been acquired, respectively, on August 2, 1985, and July 4, 2015, were used. The support vector machine method was then used to classify the images. The results showed that Isfahan city had been encountered with an increase of impervious surfaces; in fact, this class covered 15% of the total area in 1985, while this value had been increased to 30% in 2015. Then LST zoning maps were created, indicating that the bare land and impervious surfaces categories were dominant in high temperature zones, while in the zones where water was present or NDVI was high, LST was low. Then, the landscape metrics in each of the LST zones were analyzed in relation to the LULC changes, showing that LULC changes due to urban expansion changed such landscape properties as the percentage of landscape, patch density, large patch index, and aggregation index. This information could be beneficial for urban planners to monitor and manage changes in the LULC patterns.

Total pollution effect of urban surface runoff.

PubMed

Luo, Hongbing; Luo, Lin; Huang, Gu; Liu, Ping; Li, Jingxian; Hu, Sheng; Wang, Fuxiang; Xu, Rui; Huang, Xiaoxue

2009-01-01

For pollution research with regard to urban surface runoff, most sampling strategies to date have focused on differences in land usage. With single land-use sampling, total surface runoff pollution effect cannot be evaluated unless every land usage spot is monitored. Through a new sampling strategy known as mixed stormwater sampling for a street community at discharge outlet adjacent to river, this study assessed the total urban surface runoff pollution effect caused by a variety of land uses and the pollutants washed off from the rain pipe system in the Futian River watershed in Shenzhen City of China. The water quality monitoring indices were COD (chemical oxygen demand), TSS (total suspend solid), TP (total phosphorus), TN (total nitrogen) and BOD (biochemical oxygen demand). The sums of total pollution loads discharged into the river for the four indices of COD, TSS, TN, and TP over all seven rainfall events were very different. The mathematical model for simulating total pollution loads was established from discharge outlet mixed stormwater sampling of total pollution loads on the basis of four parameters: rainfall intensity, total land area, impervious land area, and pervious land area. In order to treat surface runoff pollution, the values of MFF30 (mass first flush ratio) and FF30 (first 30% of runoff volume) can be considered as split-flow control criteria to obtain more effective and economical design of structural BMPs (best management practices) facilities.

A Multi-scale Approach to Urban Thermal Analysis

NASA Technical Reports Server (NTRS)

Gluch, Renne; Quattrochi, Dale A.

2005-01-01

An environmental consequence of urbanization is the urban heat island effect, a situation where urban areas are warmer than surrounding rural areas. The urban heat island phenomenon results from the replacement of natural landscapes with impervious surfaces such as concrete and asphalt and is linked to adverse economic and environmental impacts. In order to better understand the urban microclimate, a greater understanding of the urban thermal pattern (UTP), including an analysis of the thermal properties of individual land covers, is needed. This study examines the UTP by means of thermal land cover response for the Salt Lake City, Utah, study area at two scales: 1) the community level, and 2) the regional or valleywide level. Airborne ATLAS (Advanced Thermal Land Applications Sensor) data, a high spatial resolution (10-meter) dataset appropriate for an environment containing a concentration of diverse land covers, are used for both land cover and thermal analysis at the community level. The ATLAS data consist of 15 channels covering the visible, near-IR, mid-IR and thermal-IR wavelengths. At the regional level Landsat TM data are used for land cover analysis while the ATLAS channel 13 data are used for the thermal analysis. Results show that a heat island is evident at both the community and the valleywide level where there is an abundance of impervious surfaces. ATLAS data perform well in community level studies in terms of land cover and thermal exchanges, but other, more coarse-resolution data sets are more appropriate for large-area thermal studies. Thermal response per land cover is consistent at both levels, which suggests potential for urban climate modeling at multiple scales.

A Meta-Analysis of Global Urban Land Expansion

PubMed Central

Seto, Karen C.; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K.

2011-01-01

The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

Determining the impact of urban components on land surface temperature of Istanbul by using remote sensing indices.

PubMed

Bektaş Balçik, Filiz

2014-02-01

For the past 60 years, Istanbul has been experiencing an accelerated urban expansion. This urban expansion is leading to the replacement of natural surfaces by various artificial materials. This situation has a critical impact on the environment due to the alteration of heat energy balance. In this study, the effect upon the urban heat island (UHI) of Istanbul was analyzed using 2009 dated Landsat 5 Thematic Mapper (TM) data. An Index Based Built-up Index (IBI) was used to derive artificial surfaces in the study area. To produce the IBI index, Soil-Adjusted Vegetation Index, Normalized Difference Built-up Index, and Modified Normalized Difference Water Index were calculated. Land surface temperature (LST) distribution was derived from Landsat 5 TM images using a mono-window algorithm. In addition, 24 transects were selected, and different regression models were applied to explore the correlation between LST and IBI index. The results show that artificial surfaces have a positive exponential relationship with LST rather than a simple linear one. An ecological evaluation index of the region was calculated to explore the impact of both the vegetated land and the artificial surfaces on the UHI. Therefore, the quantitative relationship of urban components (artificial surfaces, vegetation, and water) and LST was examined using multivariate statistical analysis, and the correlation coefficient was obtained as 0.829. This suggested that the areas with a high rate of urbanization will accelerate the rise of LST and UHI in Istanbul.

Adverse Impact of Electromagnetic Radiation on Urban Environment and Natural Resources using Optical Sensors

NASA Astrophysics Data System (ADS)

Kumar, Pawan; Katiyar, Swati; Rani, Meenu

2016-07-01

We are living in the age of a rapidly growing population and changing environmental conditions with an advance technical capacity.This has resulted in wide spread land cover change. One of the main causes for increasing urban heat is that more than half of the world's population lives in a rapidly growing urbanized environment. Satellite data can be highly useful to map change in land cover and other environmental phenomena with the passage of time. Among several human-induced environmental and urban thermal problems are reported to be negatively affecting urban residents in many ways. The built-up structures in urbanized areas considerably alter land cover thereby affecting thermal energy flow which leads to development of elevated surface and air temperature. The phenomenon Urban Heat Island implies 'island' of high temperature in cities, surrounded by relatively lower temperature in rural areas. The UHI for the temporal period is estimated using geospatial techniques which are then utilized for the impact assessment on climate of the surrounding regions and how it reduce the sustainability of the natural resources like air, vegetation. The present paper describes the methodology and resolution dynamic urban heat island change on climate using the geospatial approach. NDVI were generated using day time LANDSAT ETM+ image of 1990, 2000 and 2013. Temperature of various land use and land cover categories was estimated. Keywords: NDVI, Surface temperature, Dynamic changes.

Understanding land use change impacts on microclimate using Weather Research and Forecasting (WRF) model

DOE PAGES

Li, Xia; Mitra, Chandana; Dong, Li; ...

2017-02-02

In order to explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Our results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under themore » urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. Our study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.« less

Understanding land use change impacts on microclimate using Weather Research and Forecasting (WRF) model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xia; Mitra, Chandana; Dong, Li

In order to explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Our results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under themore » urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. Our study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.« less

Understanding land use change impacts on microclimate using Weather Research and Forecasting (WRF) model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xia; Mitra, Chandana; Dong, Li

To explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under the urbanization scenario, butmore » expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. This study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region. (C) 2017 Elsevier Ltd. All rights reserved.« less

Analysis of the Intra-City Variation of Urban Heat Island and its Relation to Land Surface/cover Parameters

NASA Astrophysics Data System (ADS)

Gerçek, D.; Güven, İ. T.; Oktay, İ. Ç.

2016-06-01

Along with urbanization, sealing of vegetated land and evaporation surfaces by impermeable materials, lead to changes in urban climate. This phenomenon is observed as temperatures several degrees higher in densely urbanized areas compared to the rural land at the urban fringe particularly at nights, so-called Urban Heat Island. Urban Heat Island (UHI) effect is related with urban form, pattern and building materials so far as it is associated with meteorological conditions, air pollution, excess heat from cooling. UHI effect has negative influences on human health, as well as other environmental problems such as higher energy demand, air pollution, and water shortage. Urban Heat Island (UHI) effect has long been studied by observations of air temperature from thermometers. However, with the advent and proliferation of remote sensing technology, synoptic coverage and better representations of spatial variation of surface temperature became possible. This has opened new avenues for the observation capabilities and research of UHIs. In this study, "UHI effect and its relation to factors that cause it" is explored for İzmit city which has been subject to excess urbanization and industrialization during the past decades. Spatial distribution and variation of UHI effect in İzmit is analysed using Landsat 8 and ASTER day & night images of 2015 summer. Surface temperature data derived from thermal bands of the images were analysed for UHI effect. Higher temperatures were classified into 4 grades of UHIs and mapped both for day and night. Inadequate urban form, pattern, density, high buildings and paved surfaces at the expanse of soil ground and vegetation cover are the main factors that cause microclimates giving rise to spatial variations in temperatures across cities. These factors quantified as land surface/cover parameters for the study include vegetation index (NDVI), imperviousness (NDISI), albedo, solar insolation, Sky View Factor (SVF), building envelope, distance to sea, and traffic space density. These parameters that cause variation in intra-city temperatures were evaluated for their relationship with different grades of UHIs. Zonal statistics of UHI classes and variations in average value of parameters were interpreted. The outcomes that highlight local temperature peaks are proposed to the attention of the decision makers for mitigation of Urban Heat Island effect in the city at local and neighbourhood scale.

Soil chemical and physical properties that differentiate urban land-use and cover types

Treesearch

R.V. Pouyat; I.D. Yesilonis; J. Russell-Anelli; N.K. Neerchal

2007-01-01

We investigated the effects of land use and cover and surface geology on soil properties in Baltimore, MD, with the objectives to: (i) measure the physical and chemical properties of surface soils (0?10 cm) by land use and cover; and (ii) ascertain whether land use and cover explain differences in these properties relative to surface geology. Mean and median values of...

Multi-scale landscape factors influencing stream water quality in the state of Oregon.

PubMed

Nash, Maliha S; Heggem, Daniel T; Ebert, Donald; Wade, Timothy G; Hall, Robert K

2009-09-01

Enterococci bacteria are used to indicate the presence of human and/or animal fecal materials in surface water. In addition to human influences on the quality of surface water, a cattle grazing is a widespread and persistent ecological stressor in the Western United States. Cattle may affect surface water quality directly by depositing nutrients and bacteria, and indirectly by damaging stream banks or removing vegetation cover, which may lead to increased sediment loads. This study used the State of Oregon surface water data to determine the likelihood of animal pathogen presence using enterococci and analyzed the spatial distribution and relationship of biotic (enterococci) and abiotic (nitrogen and phosphorous) surface water constituents to landscape metrics and others (e.g. human use, percent riparian cover, natural covers, grazing, etc.). We used a grazing potential index (GPI) based on proximity to water, land ownership and forage availability. Mean and variability of GPI, forage availability, stream density and length, and landscape metrics were related to enterococci and many forms of nitrogen and phosphorous in standard and logistic regression models. The GPI did not have a significant role in the models, but forage related variables had significant contribution. Urban land use within stream reach was the main driving factor when exceeding the threshold (> or =35 cfu/100 ml), agriculture was the driving force in elevating enterococci in sites where enterococci concentration was <35 cfu/100 ml. Landscape metrics related to amount of agriculture, wetlands and urban all contributed to increasing nutrients in surface water but at different scales. The probability of having sites with concentrations of enterococci above the threshold was much lower in areas of natural land cover and much higher in areas with higher urban land use within 60 m of stream. A 1% increase in natural land cover was associated with a 12% decrease in the predicted odds of having a site exceeding the threshold. Opposite to natural land cover, a one unit change in each of manmade barren and urban land use led to an increase of the likelihood of exceeding the threshold by 73%, and 11%, respectively. Change in urban land use had a higher influence on the likelihood of a site exceeding the threshold than that of natural land cover.

Land Use and Land Cover Change, Urban Heat Island Phenomenon, and Health Implications: A Remote Sensing Approach

NASA Technical Reports Server (NTRS)

Lo, C. P.; Quattrochi, Dale A.

2003-01-01

Land use and land cover maps of Atlanta Metropolitan Area in Georgia were produced from Landsat MSS and TM images for 1973,1979,1983,1987,1992, and 1997, spanning a period of 25 years. Dramatic changes in land use and land cover have occurred with loss of forest and cropland to urban use. In particular, low-density urban use, which includes largely residential use, has increased by over 119% between 1973 and 1997. These land use and land cover changes have drastically altered the land surface characteristics. An analysis of Landsat images revealed an increase in surface temperature and a decline in NDVI from 1973 to 1997. These changes have forced the development of a significant urban heat island effect and an increase in ground level ozone production to such an extent, that Atlanta has violated EPA's ozone level standard in recent years. The urban heat island initiated precipitation events that were identified between 1996 and 2000 tended to occur near high-density urban areas but outside the I-285 loop that traverses around the Central Business District, i.e. not in the inner city area, but some in close proximity to the highways. The health implications were investigated by comparing the spatial patterns of volatile organic compounds (VOC) and nitrogen oxides (NOx) emissions, the two ingredients that form ozone by reacting with sunlight, with those of rates of cardiovascular and chronic lower respiratory diseases. A clear core-periphery pattern was revealed for both VOC and NOx emissions, but the spatial pattern was more random in the cases of rates of cardiovascular and chronic lower respiratory diseases. Clearly, factors other than ozone pollution were involved in explaining the rates of these diseases. Further research is therefore needed to understand the health geography and its relationship to land use and land cover change as well as urban heat island effect. This paper illustrates the usefulness of a remote sensing approach for this purpose.

Simulated Climate Impacts of Mexico City's Historical Urban Expansion

NASA Astrophysics Data System (ADS)

Benson-Lira, Valeria

Urbanization, a direct consequence of land use and land cover change, is responsible for significant modification of local to regional scale climates. It is projected that the greatest urban growth of this century will occur in urban areas in the developing world. In addition, there is a significant research gap in emerging nations concerning this topic. Thus, this research focuses on the assessment of climate impacts related to urbanization on the largest metropolitan area in Latin America: Mexico City. Numerical simulations using a state-of-the-science regional climate model are utilized to address a trio of scientifically relevant questions with wide global applicability. The importance of an accurate representation of land use and land cover is first demonstrated through comparison of numerical simulations against observations. Second, the simulated effect of anthropogenic heating is quantified. Lastly, numerical simulations are performed using pre-historic scenarios of land use and land cover to examine and quantify the impact of Mexico City's urban expansion and changes in surface water features on its regional climate.

Evaluation of the WRF-Urban Modeling System Coupled to Noah and Noah-MP Land Surface Models Over a Semiarid Urban Environment

NASA Astrophysics Data System (ADS)

Salamanca, Francisco; Zhang, Yizhou; Barlage, Michael; Chen, Fei; Mahalov, Alex; Miao, Shiguang

2018-03-01

We have augmented the existing capabilities of the integrated Weather Research and Forecasting (WRF)-urban modeling system by coupling three urban canopy models (UCMs) available in the WRF model with the new community Noah with multiparameterization options (Noah-MP) land surface model (LSM). The WRF-urban modeling system's performance has been evaluated by conducting six numerical experiments at high spatial resolution (1 km horizontal grid spacing) during a 15 day clear-sky summertime period for a semiarid urban environment. To assess the relative importance of representing urban surfaces, three different urban parameterizations are used with the Noah and Noah-MP LSMs, respectively, over the two major cities of Arizona: Phoenix and Tucson metropolitan areas. Our results demonstrate that Noah-MP reproduces somewhat better than Noah the daily evolution of surface skin temperature and near-surface air temperature (especially nighttime temperature) and wind speed. Concerning the urban areas, bulk urban parameterization overestimates nighttime 2 m air temperature compared to the single-layer and multilayer UCMs that reproduce more accurately the daily evolution of near-surface air temperature. Regarding near-surface wind speed, only the multilayer UCM was able to reproduce realistically the daily evolution of wind speed, although maximum winds were slightly overestimated, while both the single-layer and bulk urban parameterizations overestimated wind speed considerably. Based on these results, this paper demonstrates that the new community Noah-MP LSM coupled to an UCM is a promising physics-based predictive modeling tool for urban applications.

Urban watershed modeling in Seattle, Washington using VELMA – a spatially explicit ecohydrological watershed model

EPA Science Inventory

Urban watersheds are notoriously difficult to model due to their complex, small-scale combinations of landscape and land use characteristics including impervious surfaces that ultimately affect the hydrologic system. We utilized EPA’s Visualizing Ecosystem Land Management A...

Modelling the effect of urbanization on the transmission of an infectious disease.

PubMed

Zhang, Ping; Atkinson, Peter M

2008-01-01

This paper models the impact of urbanization on infectious disease transmission by integrating a CA land use development model, population projection matrix model and CA epidemic model in S-Plus. The innovative feature of this model lies in both its explicit treatment of spatial land use development, demographic changes, infectious disease transmission and their combination in a dynamic, stochastic model. Heuristically-defined transition rules in cellular automata (CA) were used to capture the processes of both land use development with urban sprawl and infectious disease transmission. A population surface model and dwelling distribution surface were used to bridge the gap between urbanization and infectious disease transmission. A case study is presented involving modelling influenza transmission in Southampton, a dynamically evolving city in the UK. The simulation results for Southampton over a 30-year period show that the pattern of the average number of infection cases per day can depend on land use and demographic changes. The modelling framework presents a useful tool that may be of use in planning applications.

Project ATLANTA (ATlanta Land-use ANalysis: Temperature and Air quality): A Study of how the Urban Landscape Affects Meteorology and Air Quality Through Time

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G.; Lo, C. P.; Kidder, Stanley Q.; Hafner, Jan; Taha, Haider; Bornstein, Robert D.; Gillies, Robert R.; Gallo, Kevin P.

1998-01-01

It is our intent through this investigation to help facilitate measures that can be Project ATLANTA (ATlanta Land-use ANalysis: applied to mitigate climatological or air quality Temperature and Air-quality) is a NASA Earth degradation, or to design alternate measures to sustain Observing System (EOS) Interdisciplinary Science or improve the overall urban environment in the future. investigation that seeks to observe, measure, model, and analyze how the rapid growth of the Atlanta. The primary objectives for this research effort are: 1) To In the last half of the 20th century, Atlanta, investigate and model the relationship between Atlanta Georgia has risen as the premier commercial, urban growth, land cover change, and the development industrial, and transportation urban area of the of the urban heat island phenomenon through time at southeastern United States. The rapid growth of the nested spatial scales from local to regional; 2) To Atlanta area, particularly within the last 25 years, has investigate and model the relationship between Atlanta made Atlanta one of the fastest growing metropolitan urban growth and land cover change on air quality areas in the United States. The population of the through time at nested spatial scales from local to Atlanta metropolitan area increased 27% between 1970 regional; and 3) To model the overall effects of urban and 1980, and 33% between 1980-1990 (Research development on surface energy budget characteristics Atlanta, Inc., 1993). Concomitant with this high rate of across the Atlanta urban landscape through time at population growth, has been an explosive growth in nested spatial scales from local to regional. Our key retail, industrial, commercial, and transportation goal is to derive a better scientific understanding of how services within the Atlanta region. This has resulted in land cover changes associated with urbanization in the tremendous land cover change dynamics within the Atlanta area, principally in transforming forest lands to metropolitan region, wherein urbanization has urban land covers through time, has, and will, effect consumed vast acreas of land adjacent to the city local and regional climate, surface energy flux, and air proper and has pushed the rural/urban fringe farther quality characteristics. Allied with this goal is the and farther away from the original Atlanta urban core. prospect that the results from this research can be An enormous transition of land from forest and applied by urban planners, environmental managers agriculture to urban land uses has occurred in the and other decision-makers, for determining how Atlanta area in the last 25 years, along with subsequent urbanization has impacted the climate and overall

A Remote Sensing Approach for Urban Environmental Decision-Making: An Atlanta, Georgia Case Study

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Luvall, Jeffrey C.; Rickman, Douglas L.; Laymon, Charles A.; Estes, Maurice G., Jr.; Howell, Burgess F.; Arnold, James E. (Technical Monitor)

2002-01-01

Unquestionably, urbanization causes tremendous changes in land cover and land use, as well as impacting a host of environmental characteristics. For example, unlike natural surfaces, urban surfaces have very different thermal energy properties whereby they store solar energy throughout the day and continue to release it as heat well after sunset. This effect, known as the 'Urban Heat Island', serves as a catalyst for chemical reactions from vehicular exhaust and industrial activities leading to the deterioration in air quality, especially exacerbating the production of ground level ozone. 'Cool Community' strategies that utilize remote sensing data, are now being implemented as a way to reduce the impacts of the urban heat island and its subsequent environmental impacts. This presentation focuses on how remote sensing data have been used to provide descriptive and quantitative data for characterizing the Atlanta, Georgia metropolitan area - particularly for measuring surface energy fluxes, such as the thermal or "heat" energy that emanates from different land cover types across the Atlanta urban landscape. In turn, this information is useful for developing a better understanding of how the thermal characteristics of the city surface affect the urban heat island phenomena and, ultimately, air quality and other environmental parameters over the Atlanta metropolitan region. Additionally, this paper also provides insight on how remote sensing, with its synoptic approach, can be used to provide urban planners, local, state, and federal government officials, and other decision-makers, as well as the general public, with information to better manage urban areas as sustainable environments.

Relationship Between Landcover Pattern and Surface Net Radiation in AN Coastal City

NASA Astrophysics Data System (ADS)

Zhao, X.; Liu, L.; Liu, X.; Zhao, Y.

2016-06-01

Taking Xiamen city as the study area this research first retrieved surface net radiation using meteorological data and Landsat 5 TM images of the four seasons in the year 2009. Meanwhile the 65 different landscape metrics of each analysis unit were acquired using landscape analysis method. Then the most effective landscape metrics affecting surface net radiation were determined by correlation analysis, partial correlation analysis, stepwise regression method, etc. At both class and landscape levels, this paper comprehensively analyzed the temporal and spatial variations of the surface net radiation as well as the effects of land cover pattern on it in Xiamen from a multi-seasonal perspective. The results showed that the spatial composition of land cover pattern shows significant influence on surface net radiation while the spatial allocation of land cover pattern does not. The proportions of bare land and forest land are effective and important factors which affect the changes of surface net radiation all the year round. Moreover, the proportion of forest land is more capable for explaining surface net radiation than the proportion of bare land. So the proportion of forest land is the most important and continuously effective factor which affects and explains the cross-seasonal differences of surface net radiation. This study is helpful in exploring the formation and evolution mechanism of urban heat island. It also gave theoretical hints and realistic guidance for urban planning and sustainable development.

Effects of urban tree canopy loss on land surface temperature magnitude and timing

Treesearch

Arthur Elmes; John Rogan; Christopher Williams; Samuel Ratick; David Nowak; Deborah Martin

2017-01-01

Urban Tree Canopy (UTC) plays an important role in moderating the Surface Urban Heat Island (SUHI) effect, which poses threats to human health due to substantially increased temperatures relative to rural areas. UTC coverage is associated with reduced urban temperatures, and therefore benefits both human health and reducing energy use in cities. Measurement of this...

Evaluating the effects of historical land cover change on summertime weather and climate in New Jersey: Land cover and surface energy budget changes

USGS Publications Warehouse

Wichansky, P.S.; Steyaert, L.T.; Walko, R.L.; Waever, C.P.

2008-01-01

The 19th-century agrarian landscape of New Jersey (NJ) and the surrounding region has been extensively transformed to the present-day land cover by urbanization, reforestation, and localized areas of deforestation. This study used a mesoscale atmospheric numerical model to investigate the sensitivity of the warm season climate of NJ to these land cover changes. Reconstructed 1880s-era and present-day land cover data sets were used as surface boundary conditions for a set of simulations performed with the Regional Atmospheric Modeling System (RAMS). Three-member ensembles with historical and present-day land cover were compared to examine the sensitivity of surface air and dew point temperatures, rainfall, and the individual components of the surface energy budget to these land cover changes. Mean temperatures for the present-day landscape were 0.3-0.6??C warmer than for the historical landscape over a considerable portion of NJ and the surrounding region, with daily maximum temperatures at least 1.0??C warmer over some of the highly urbanized locations. Reforested regions, however, were slightly cooler. Dew point temperatures decreased by 0.3-0.6??C, suggesting drier, less humid near-surface air for the present-day landscape. Surface warming was generally associated with repartitioning of net radiation from latent to sensible heat flux, and conversely for cooling. While urbanization was accompanied by strong surface albedo decreases and increases in net shortwave radiation, reforestation and potential changes in forest composition have generally increased albedos and also enhanced landscape heterogeneity. The increased deciduousness of forests may have further reduced net downward longwave radiation. Copyright 2008 by the American Geophysical Union.

Exploring Remote Sensing Products Online with Giovanni for Studying Urbanization

NASA Technical Reports Server (NTRS)

Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina; Kempler, Steve

2012-01-01

Recently, a Large amount of MODIS land products at multi-spatial resolutions have been integrated into the online system, Giovanni, to support studies on land cover and land use changes focused on Northern Eurasia and Monsoon Asia regions. Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) is a Web-based application developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES-DISC) providing a simple and intuitive way to visualize, analyze, and access Earth science remotely-sensed and modeled data. The customized Giovanni Web portals (Giovanni-NEESPI and Giovanni-MAIRS) are created to integrate land, atmospheric, cryospheric, and social products, that enable researchers to do quick exploration and basic analyses of land surface changes and their relationships to climate at global and regional scales. This presentation documents MODIS land surface products in Giovanni system. As examples, images and statistical analysis results on land surface and local climate changes associated with urbanization over Yangtze River Delta region, China, using data in Giovanni are shown.

Assessing surface albedo change and its induced radiation budget under rapid urbanization with Landsat and GLASS data

NASA Astrophysics Data System (ADS)

Hu, Yonghong; Jia, Gensuo; Pohl, Christine; Zhang, Xiaoxuan; van Genderen, John

2016-02-01

Radiative forcing (RF) induced by land use (mainly surface albedo) change is still not well understood in climate change science, especially the effects of changes in urban albedo due to rapid urbanization on the urban radiation budget. In this study, a modified RF derivation approach based on Landsat images was used to quantify changes in the solar radiation budget induced by variations in surface albedo in Beijing from 2001 to 2009. Field radiation records from a Beijing meteorological station were used to identify changes in RF at the local level. There has been rapid urban expansion over the last decade, with the urban land area increasing at about 3.3 % annually from 2001 to 2009. This has modified three-dimensional urban surface properties, resulting in lower albedo due to complex building configurations of urban centers and higher albedo on flat surfaces of suburban areas and cropland. There was greater solar radiation (6.93 × 108 W) in the urban center in 2009 than in 2001. However, large cropland and urban fringe areas caused less solar radiation absorption. RF increased with distance from the urban center (less than 14 km) and with greater urbanization, with the greatest value being 0.41 W/m2. The solar radiation budget in urban areas was believed to be mainly influenced by urban structural changes in the horizontal and vertical directions. Overall, the results presented herein indicate that cumulative urbanization impacts on the natural radiation budget could evolve into an important driver of local climate change.

The impact of urban morphology and land cover on the sensible heat flux retrieved by satellite and in-situ observations

NASA Astrophysics Data System (ADS)

Gawuc, L.; Łobocki, L.; Kaminski, J. W.

2017-12-01

Land surface temperature (LST) is a key parameter in various applications for urban environments research. However, remotely-sensed radiative surface temperature is not equivalent to kinetic nor aerodynamic surface temperature (Becker and Li, 1995; Norman and Becker, 1995). Thermal satellite observations of urban areas are also prone to angular anisotropy which is directly connected with the urban structure and relative sun-satellite position (Hu et al., 2016). Sensible heat flux (Qh) is the main component of surface energy balance in urban areas. Retrieval of Qh, requires observations of, among others, a temperature gradient. The lower level of temperature measurement is commonly replaced by remotely-sensed radiative surface temperature (Chrysoulakis, 2003; Voogt and Grimmond, 2000; Xu et al., 2008). However, such replacement requires accounting for the differences between aerodynamic and radiative surface temperature (Chehbouni et al., 1996; Sun and Mahrt, 1995). Moreover, it is important to avoid micro-scale processes, which play a major role in the roughness sublayer. This is due to the fact that Monin-Obukhov similarity theory is valid only in dynamic sublayer. We will present results of the analyses of the impact of urban morphology and land cover on the seasonal changes of sensible heat flux (Qh). Qh will be retrieved by two approaches. First will be based on satellite observations of radiative surface temperature and second will be based on in-situ observations of kinetic road temperature. Both approaches will utilize wind velocity, and air temperature observed in-situ. We will utilize time series of MODIS LST observations for the period of 2005-2014 as well as simultaneous in-situ observations collected by road weather network (9 stations). Ground stations are located across the city of Warsaw, outside the city centre in low-rise urban structure. We will account for differences in urban morphology and land cover in the proximity of ground stations. We will utilize DEM and Urban Atlas LULC database and freely available visible aerial and satellite imagery. All the analyses will be conducted for single pixels, which will be closest to the locations of the ground stations (nearest neighbour approach). Appropriate figures showing the seasonal variability of Qh will be presented.

Associating Land Surface Temperature Retrieved From Satellite and Unmanned Aerial Vehicle Data With Urban Cover and Topography in Aburrá Valley

NASA Astrophysics Data System (ADS)

Guzmán, G.; Hoyos Ortiz, C. D.

2017-12-01

Urban heat island effect commonly refers to temperature differences between urban areas and their countrysides due to urbanization. These temperature differences are evident at surface, and within the canopy and the boundary layer. This effect is heterogeneous within the city, and responds to urban morphology, prevailing materials, amount of vegetation, among others, which are also important in the urban balance of energy. In order to study the relationship between land surface temperature (LST) and urban coverage over Aburrá Valley, which is a narrow valley locate at tropical Andes in northern South America, Landsat 8 mission products of LST, density of vegetation (normalized difference vegetation index, NDVI), and a proxy of soil humidity are derived and used. The results are analyzed from the point of view of dominant urban form and settlement density at scale of neighborhoods, and also from potential downward solar radiation received at the surface. Besides, specific sites were chosen to obtain LST from thermal imaging using an unmanned aerial vehicle to characterize micro-scale patterns and to validate Landast retrievals. Direct relationships between LST, NDVI, soil humidity, and duration of insolation are found, showing the impact of the current spatial distribution of land uses on surface temperature over Aburrá Valley. In general, the highest temperatures correspond to neighborhoods with large, flat-topped buildings in commercial and industrial areas, and low-rise building in residential areas with scarce vegetation, all on the valley bottom. Landsat images are in the morning for the Aburrá Valley, for that reason the coldest temperatures are prevalent at certain orientation of the hillslope, according with the amount of radiation received from sunrise to time of data.

Monitoring and Predicting Land-use Changes and the Hydrology of the Urbanized Paochiao Watershed in Taiwan Using Remote Sensing Data, Urban Growth Models and a Hydrological Model.

PubMed

Lin, Yu-Pin; Lin, Yun-Bin; Wang, Yen-Tan; Hong, Nien-Ming

2008-02-04

Monitoring and simulating urban sprawl and its effects on land-use patterns andhydrological processes in urbanized watersheds are essential in land-use and waterresourceplanning and management. This study applies a novel framework to the urbangrowth model Slope, Land use, Excluded land, Urban extent, Transportation, andHillshading (SLEUTH) and land-use change with the Conversion of Land use and itsEffects (CLUE-s) model using historical SPOT images to predict urban sprawl in thePaochiao watershed in Taipei County, Taiwan. The historical and predicted land-use datawas input into Patch Analyst to obtain landscape metrics. This data was also input to theGeneralized Watershed Loading Function (GWLF) model to analyze the effects of futureurban sprawl on the land-use patterns and watershed hydrology. The landscape metrics ofthe historical SPOT images show that land-use patterns changed between 1990-2000. TheSLEUTH model accurately simulated historical land-use patterns and urban sprawl in thePaochiao watershed, and simulated future clustered land-use patterns (2001-2025). TheCLUE-s model also simulated land-use patterns for the same period and yielded historical trends in the metrics of land-use patterns. The land-use patterns predicted by the SLEUTHand CLUE-s models show the significant impact urban sprawl will have on land-usepatterns in the Paochiao watershed. The historical and predicted land-use patterns in thewatershed tended to fragment, had regular shapes and interspersion patterns, but wererelatively less isolated in 2001-2025 and less interspersed from 2005-2025 compared withland-use pattern in 1990. During the study, the variability and magnitude of hydrologicalcomponents based on the historical and predicted land-use patterns were cumulativelyaffected by urban sprawl in the watershed; specifically, surface runoff increasedsignificantly by 22.0% and baseflow decreased by 18.0% during 1990-2025. The proposedapproach is an effective means of enhancing land-use monitoring and management ofurbanized watersheds.

Assessing the impact of urbanization on urban climate by remote satellite perspective: a case study in Danang city, Vietnam

NASA Astrophysics Data System (ADS)

Hoang Khanh Linh, N.; Van Chuong, H.

2015-04-01

Urban climate, one of the challenges of human being in 21 century, is known as the results of land use/cover transformation. Its characteristics are distinguished by different varieties of climatic conditions in comparison with those of less built-up areas. The alterations lead to "Urban Heat Island", in which temperature in urban places is higher than surrounding environment. This happens not only in mega cities but also in less urbanized sites. The results determine the change of land use/cover and land surface temperature in Danang city by using multi-temporal Landsat and ASTER data for the period of 1990-2009. Based on the supervised classification method of maximum likelihood algorithm, satellite images in 1990, 2003, 2009 were classified into five classes: water, forest, shrub, agriculture, barren land and built-up area. For accuracy assessment, the error metric tabulations of mapped classes and reference classes were made. The Kappa statistics, derived from error matrices, were over 80% for all of land use maps. An comparison change detection algorithm was made in three intervals, 1990-2003, 2003-2009 and 1990-2009. The results showed that built-up area increased from 8.95% to 17.87% between 1990 and 2009, while agriculture, shrub and barren decreased from 12.98% to 7.53%, 15.72% to 9.89% and 3.88% to 1.77% due to urbanization that resulted from increasing of urban population and economic development, respectively. Land surface temperature (LST) maps were retrieved from thermal infrared bands of Landsat and ASTER data. The result indicated that the temperature in study area increased from 39oC to 41oC for the period of 1990-2009. Our analysis showed that built-up area had the highest LST values, whereas water bodies had the least LST. This study is expected to be useful for decision makers to make an appropriate land use planning which can mitigate the effect to urban climate.

Seeking More Effective Management of Freshwater Pollution

EPA Science Inventory

The atmosphere contains airborne pollutants such as mercury, nitrogen oxides, and sulfur oxides released from automobiles, factories, and power plants. Similarly, land surfaces such as croplands, feedlots, logged forests, construction sites, and urban land surfaces may be reserv...

Changes in Urban Climate due to Future Land-Use Changes based on Population Changes in the Nagoya Region

NASA Astrophysics Data System (ADS)

Adachi, S. A.; Hara, M.; Takahashi, H. G.; Ma, X.; Yoshikane, T.; Kimura, F.

2013-12-01

Severe hot weather in summer season becomes a big social problem in metropolitan areas, including the Nagoya region in Japan. Surface air temperature warming is projected in the future. Therefore, the reduction of surface air temperature is an urgent issue in the urban area. Although there are several studies dealing with the effects of global climate change and urbanization to the local climate in the future, these studies tend to ignore the future population changes. This study estimates future land-use scenarios associated with the multi-projections of future population and investigates the impacts of these scenarios on the surface temperature change. The Weather Research and Forecast model ver. 3.3.1 (hereafter, WRF) was used in this study. The horizontal resolutions were 20km, 4km, and 2km, for outer, middle, and inner domains, respectively. The results from the inner domain, covering the Nagoya region, were used for the analysis. The Noah land surface model and the single-layer urban canopy model were applied to calculate the land surface processes and urban surface processes, respectively. The initial and boundary conditions were given from the NCEP/NCAR reanalysis data in August 2010. The urban area ratio used in the WRF model was calculated from the future land-use data provided by the S8 project. The land-use data was created as follows. (1) Three scenarios of population, namely, with high-fertility assumption and low-mortality assumption (POP-high), with medium-fertility assumption and medium-mortality assumption (POP-med), and with low-fertility assumption and high-mortality assumption (POP-low), are estimated using the method proposed by Ariga and Matsuhashi (2012). These scenarios are based on the future projections provided by the National Institute of Population and Social Security Research. (2) The future changes in urban area ratio were assumed to be proportional to the population change (Hanasaki et al., 2012). The averaged urban area ratio in the Nagoya region was 0.37 in 2010. The area ratios were projected to reach a peak in 2010 to 2020, and then to decrease in the future in all of scenarios. The urban heat island intensity in the Nagoya region is about 1.5°C in 2010. In contrast, the differences of surface temperature is -0.17°C, -0.21°C, and -0.30°C in POP-high, POP-med, and POP-low, from the current situation in 2010. These impacts correspond to the 10% to 20% of current urban heat island intensity. However, the changes in the efficiency of energy consumption were not considered. Considering that the future surface temperature change is projected to be about 1.2°C to 4°C in 2070, it is required to quantitatively evaluate future urban scenarios including the mitigation strategies for urban heat island such as the improvement of energy consumption, greening, and so on. Acknowledgments. This study was supported by the Research Program on Climate Change Adaptation (RECCA) Fund by Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan and the Global Environment Research Fund (S-8) of the Ministry of the Environment of Japan.

Effects of landscape composition and pattern on land surface temperature: An urban heat island study in the megacities of Southeast Asia.

PubMed

Estoque, Ronald C; Murayama, Yuji; Myint, Soe W

2017-01-15

Due to its adverse impacts on urban ecological environment and the overall livability of cities, the urban heat island (UHI) phenomenon has become a major research focus in various interrelated fields, including urban climatology, urban ecology, urban planning, and urban geography. This study sought to examine the relationship between land surface temperature (LST) and the abundance and spatial pattern of impervious surface and green space in the metropolitan areas of Bangkok (Thailand), Jakarta (Indonesia), and Manila (Philippines). Landsat-8 OLI/TIRS data and various geospatial approaches, including urban-rural gradient, multiresolution grid-based, and spatial metrics-based techniques, were used to facilitate the analysis. We found a significant strong correlation between mean LST and the density of impervious surface (positive) and green space (negative) along the urban-rural gradients of the three cities, depicting a typical UHI profile. The correlation of impervious surface density with mean LST tends to increase in larger grids, whereas the correlation of green space density with mean LST tends to increase in smaller grids, indicating a stronger influence of impervious surface and green space on the variability of LST in larger and smaller areas, respectively. The size, shape complexity, and aggregation of the patches of impervious surface and green space also had significant relationships with mean LST, though aggregation had the most consistent strong correlation. On average, the mean LST of impervious surface is about 3°C higher than that of green space, highlighting the important role of green spaces in mitigating UHI effects, an important urban ecosystem service. We recommend that the density and spatial pattern of urban impervious surfaces and green spaces be considered in landscape and urban planning so that urban areas and cities can have healthier and more comfortable living urban environments. Copyright © 2016 Elsevier B.V. All rights reserved.

Surface temperature statistics over Los Angeles - The influence of land use

NASA Technical Reports Server (NTRS)

Dousset, Benedicte

1991-01-01

Surface temperature statistics from 84 NOAA AVHRR (Advanced Very High Resolution Radiometer) satellite images of the Los Angeles basin are interpreted as functions of the corresponding urban land-cover classified from a multispectral SPOT image. Urban heat islands observed in the temperature statistics correlate well with the distribution of industrial and fully built areas. Small cool islands coincide with highly watered parks and golf courses. There is a significant negative correlation between the afternoon surface temperature and a vegetation index computed from the SPOT image.

Urban Heat Islands in China Enhanced by Haze Pollution

NASA Astrophysics Data System (ADS)

Cao, C.; Lee, X.; Liu, S.; Oleson, K. W.; Schultz, N. M.; Xiao, W.; Zhang, M.; Zhao, L.

2015-12-01

Land conversion from natural surfaces to artificial urban structures has led to the phenomenon of urban heat island (UHI). The intensity of UHI is thought to be controlled primarily by biophysical factors such as changes in albedo, aerodynamic resistance and evapotranspiration, while influences of biogeochemical factors such as aerosol pollution have long been ignored. We hypothesize that increased downward longwave radiation associated with anthropogenic aerosols in urban air will exacerbate nighttime UHI intensity. Here we tested this hypothesis by using the MODIS satellite land surface temperature product and the Community Land Model (CLM) for 39 cities in China. Our results showed that in contrast to observations in North America and elsewhere, nighttime surface UHI of these Chinese cities (3.34 K) was greater than daytime UHI (2.06 K). Variations in the nighttime UHI among the cities were positively correlated with difference in the aerosol optical depth between urban and the adjacent rural area (confidence level p < 0.01). The CLM was able to reproduce the MODIS UHI intensity in the daytime but underestimated the observed UHI intensity at night. The model performance was improved by including an aerosol-enhanced downward longwave radiation in urban land and a more realistic anthropogenic heat flux. Our study illustrates that although climate background largely determine spatial differences in the daytime UHI, in countries like China with serious air quality problems, aerosol-induced pollution plays an important role in the night-time UHI formation. Mitigation of particulate pollution therefore has the added co-benefit by reducing UHI-related heat stress on urban residents.

Remote estimation of the surface characteristics and energy balance over an urban-rural area and the effects of surface heat flux on plume spread and concentration. M.S. Thesis; [St. Louis, Missouri, the Land Between the Lakes, Kentucky and Clarksville, Tennessee

NASA Technical Reports Server (NTRS)

Dicristofaro, D. C. (Principal Investigator)

1980-01-01

A one dimensional boundary layer model was used in conjunction with satellite derived infrared surface temperatures to deduce values of moisture availability, thermal inertia, heat and evaporative fluxes. The Penn State satellite image display system, a sophisticated image display facility, was used to remotely sense these various parameters for three cases: St. Louis, Missouri; the Land Between the Lakes, Kentucky; and Clarksville, Tennessee. The urban centers displayed the maximum daytime surface temperatures which correspond to the minimum values of moisture availability. The urban center of St. Louis and the bodies of water displayed the maximum nighttime surface temperatures which correspond to the maximum thermal inertia values. It is shown that moisture availability and thermal inertia are very much responsible for the formation of important temperature variations over the urban rural complex.

Mapping Impervious Surfaces Globally at 30m Resolution Using Global Land Survey Data

NASA Technical Reports Server (NTRS)

DeColstoun, Eric Brown; Huang, Chengquan; Tan, Bin; Smith, Sarah Elizabeth; Phillips, Jacqueline; Wang, Panshi; Ling, Pui-Yu; Zhan, James; Li, Sike; Taylor, Michael P.;

Mapping Impervious Surfaces Globally at 30m Resolution Using Landsat Global Land Survey Data

NASA Astrophysics Data System (ADS)

Brown de Colstoun, E.; Huang, C.; Wolfe, R. E.; Tan, B.; Tilton, J.; Smith, S.; Phillips, J.; Wang, P.; Ling, P.; Zhan, J.; Xu, X.; Taylor, M. P.

2013-12-01

Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (~2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified archive of the National Geospatial Intelligence Agency (NGA). For each continental area several million training pixels are derived by analysts using image segmentation algorithms and tools and then aggregated to the 30m resolution of Landsat. Here we will discuss the production/testing of this massive data set for Europe, North and South America and Africa, including assessments of the 2010 surface reflectance data. This type of analysis is only possible because of the availability of long term 30m data sets from GLS and shows much promise for integration of Landsat 8 data in the future.

Spatial-Temporal Variations of Water Quality and Its Relationship to Land Use and Land Cover in Beijing, China

PubMed Central

Chen, Xiang; Zhou, Weiqi; Pickett, Steward T. A.; Li, Weifeng; Han, Lijian

2016-01-01

Rapid urbanization with intense land use and land cover (LULC) change and explosive population growth has a great impact on water quality. The relationship between LULC characteristics and water quality provides important information for non-point sources (NPS) pollution management. In this study, we first quantified the spatial-temporal patterns of five water quality variables in four watersheds with different levels of urbanization in Beijing, China. We then examined the effects of LULC on water quality across different scales, using Pearson correlation analysis, redundancy analysis, and multiple regressions. The results showed that water quality was improved over the sampled years but with no significant difference (p > 0.05). However, water quality was significantly different among nonurban and both exurban and urban sites (p < 0.05). Forest land was positively correlated with water quality and affected water quality significantly (p < 0.05) within a 200 m buffer zone. Impervious surfaces, water, and crop land were negatively correlated with water quality. Crop land and impervious surfaces, however, affected water quality significantly (p < 0.05) for buffer sizes greater than 800 m. Grass land had different effects on water quality with the scales. The results provide important insights into the relationship between LULC and water quality, and thus for controlling NPS pollution in urban areas. PMID:27128934

Using Smart Planning to Mitigate Drought in Urban Areas: A Seasonal Simulation of the Impact of Urbanization on Precipitation in the Indianapolis Region

NASA Astrophysics Data System (ADS)

Schmid, P. E.; Niyogi, D.

2012-12-01

The Indianapolis region exhibits a precipitation distribution indicative of urban weather modification: negative bias upwind and positive bias downwind. The causes for such a distribution within an urban area arise from a combination of land-surface heterogeneity and urban aerosol-cloud interaction. This study investigates the causes of the precipitation distribution with a 120-day simulation using the Regional Atmospheric Modeling System (RAMS) coupled with the Town Energy Budget (TEB) model. Using a nested grid with a maximum resolution of 500m, a seasonal simulation of May through August, 2008 is conducted. Land surface conditions are varied, removing, expanding, and intensifying the Indianapolis urban area. Aerosol conditions are scaled by a three-dimensional combination of MODIS and CALIPSO observations, and varied in concentration and plume extent. Results from the study demonstrate the paradigm of urban precipitation modification on a seasonal time scale. The boundary between the rural and urban land surfaces weakens approaching systems upwind, decreasing precipitation in the city center. A larger urban extent diminishes the systems further. The aerosol plume downwind increases cloud lifetimes via cloud-nucleating aerosol, then invigorates precipitation via large drizzle-invigorating aerosols. The overall effect reproduces the observed negative precipitation bias upwind and positive bias downwind of the urban center. A lower concentration of aerosols leads to a higher proportion of stratiform rain over a larger area, whereas a higher concentration of aerosols leads to more convective rain and heavy rain events. This manifests in a weekly cycle of precipitation with rain most likely on weekends, and with less frequent but heavier rain events most likely during midweek, when aerosol concentrations are the highest. More intense urbanization, via both land surface and aerosol effects, creates more frequent heavy rainfall events and exacerbates dry-periods, potentially leading to premature drought onset. The wetter than average May, June, and July received more total rainfall from the heavy rainfall events, while the dry August became drier due to lack of stratiform precipitation. Smart planning solutions can partially mitigate the urban precipitation problem. In a simulation where a more intense urban Indianapolis is surrounded by a greenbelt and green roofs are implemented in the city, the urban precipitation bias becomes less significant. Upwind, the greenbelt provides surface moisture and mitigates how much precipitation systems weaken. Downwind, the greenbelt slows the transport of drizzle-invigorating aerosol, reducing the heavy rain events. The green roofs reduce the urban-rural gradient and slow the initial weakening of systems.

Remote Sensing of Atlanta's Urban Sprawl and the Distribution of Land Cover and Surface Temperatures

NASA Technical Reports Server (NTRS)

Laymon, Charles A.; Estes, Maurice G., Jr.; Quattrochi, Dale A.; Arnold, James E. (Technical Monitor)

2001-01-01

Between 1973 and 1992, an average of 20 ha of forest was lost each day to urban expansion of Atlanta, Georgia. Urban surfaces have very different thermal properties than natural surfaces-storing solar energy throughout the day and continuing to release it as sensible heat well after sunset. The resulting heat island effect serves as catalysts for chemical reactions from vehicular exhaust and industrialization leading to a deterioration in air quality. In this study, high spatial resolution multispectral remote sensing data has been used to characterize the type, thermal properties, and distribution of land surface materials throughout the Atlanta metropolitan area. Ten-meter data were acquired with the Advanced Thermal and Land Applications Sensor (ATLAS) on May 11 and 12, 1997. ATLAS is a 15-channel multispectral scanner that incorporates the Landsat TM bands with additional bands in the middle reflective infrared and thermal infrared range. The high spatial resolution permitted discrimination of discrete surface types (e.g., concrete, asphalt), individual structures (e.g., buildings, houses) and their associated thermal characteristics. There is a strong temperature contrast between vegetation and anthropomorphic features. Vegetation has a modal temperature at about 20 C, whereas asphalt shingles, pavement, and buildings have a modal temperature of about 39 C. Broad-leaf vegetation classes are indistinguishable on a thermal basis alone. There is slightly more variability (plus or minus 5 C) among the urban surfaces. Grasses, mixed vegetation and mixed urban surfaces are intermediate in temperature and are characterized by broader temperature distributions with modes of about 29 C. Thermal maps serve as a basis for understanding the distribution of "hotspots", i.e., how landscape features and urban fabric contribute the most heat to the lower atmosphere.

Remote Sensing of Atlanta's Urban Sprawl and the Distribution of Land Cover and Surface Temperature

NASA Technical Reports Server (NTRS)

Laymon, Charles A.; Estes, Maurice G., Jr.; Quattrochi, Dale A.; Goodman, H. Michael (Technical Monitor)

2001-01-01

Between 1973 and 1992, an average of 20 ha of forest was lost each day to urban expansion of Atlanta, Georgia. Urban surfaces have very different thermal properties than natural surfaces-storing solar energy throughout the day and continuing to release it as sensible heat well after sunset. The resulting heat island effect serves as catalysts for chemical reactions from vehicular exhaust and industrialization leading to a deterioration in air quality. In this study, high spatial resolution multispectral remote sensing data has been used to characterize the type, thermal properties, and distribution of land surface materials throughout the Atlanta metropolitan area. Ten-meter data were acquired with the Advanced Thermal and Land Applications Sensor (ATLAS) on May 11 and 12, 1997. ATLAS is a 15-channel multispectral scanner that incorporates the Landsat TM bands with additional bands in the middle reflective infrared and thermal infrared range. The high spatial resolution permitted discrimination of discrete surface types (e.g., concrete, asphalt), individual structures (e.g., buildings, houses) and their associated thermal characteristics. There is a strong temperature contrast between vegetation and anthropomorphic features. Vegetation has a modal temperature at about 20 C, whereas asphalt shingles, pavement, and buildings have a modal temperature of about 39 C. Broad-leaf vegetation classes are indistinguishable on a thermal basis alone. There is slightly more variability (+/-5 C) among the urban surfaces. Grasses, mixed vegetation and mixed urban surfaces are intermediate in temperature and are characterized by broader temperature distributions with modes of about 29 C. Thermal maps serve as a basis for understanding the distribution of "hotspots", i.e., how landscape features and urban fabric contribute the most heat to the lower atmosphere.

Urban Expansion Modeling Approach Based on Multi-Agent System and Cellular Automata

NASA Astrophysics Data System (ADS)

Zeng, Y. N.; Yu, M. M.; Li, S. N.

2018-04-01

Urban expansion is a land-use change process that transforms non-urban land into urban land. This process results in the loss of natural vegetation and increase in impervious surfaces. Urban expansion also alters the hydrologic cycling, atmospheric circulation, and nutrient cycling processes and generates enormous environmental and social impacts. Urban expansion monitoring and modeling are crucial to understanding urban expansion process, mechanism, and its environmental impacts, and predicting urban expansion in future scenarios. Therefore, it is important to study urban expansion monitoring and modeling approaches. We proposed to simulate urban expansion by combining CA and MAS model. The proposed urban expansion model based on MSA and CA was applied to a case study area of Changsha-Zhuzhou-Xiangtan urban agglomeration, China. The results show that this model can capture urban expansion with good adaptability. The Kappa coefficient of the simulation results is 0.75, which indicated that the combination of MAS and CA offered the better simulation result.

A High Resolution Land Cover Data Product to Remove Urban Density Over-Estimation Bias for Coupled Urban-Vegetation-Atmosphere Interaction Studies

NASA Astrophysics Data System (ADS)

Shaffer, S. R.

2017-12-01

Coupled land-atmosphere interactions in urban settings modeled with the Weather Research and Forecasting model (WRF) derive urban land cover from 30-meter resolution National Land Cover Database (NLCD) products. However, within urban areas, the categorical NLCD lose information of non-urban classifications whenever the impervious cover within a grid cell is above 0%, and the current method to determine urban area over estimates the actual area, leading to a bias of urban contribution. To address this bias of urban contribution an investigation is conducted by employing a 1-meter resolution land cover data product derived from the National Agricultural Imagery Program (NAIP) dataset. Scenes during 2010 for the Central Arizona Phoenix Long Term Ecological Research (CAP-LTER) study area, roughly a 120 km x 100 km area containing metropolitan Phoenix, are adapted for use within WRF to determine the areal fraction and urban fraction of each WRF urban class. A method is shown for converting these NAIP data into classes corresponding to NLCD urban classes, and is evaluated in comparison with current WRF implementation using NLCD. Results are shown for comparisons of land cover products at the level of input data and aggregated to model resolution (1 km). The sensitivity of WRF short-term summertime pre-monsoon predictions within metropolitan Phoenix to different input data products of land cover, to method of aggregating these data to model grid scale (1 km), for the default and derived parameter values are examined with the Noah mosaic land surface scheme adapted for using these data. Issues with adapting these non-urban NAIP classes for use in the mosaic approach will also be discussed.

Beyond Impervious: Urban Land-Cover Pattern Variation and Implications for Watershed Management

NASA Astrophysics Data System (ADS)

Beck, Scott M.; McHale, Melissa R.; Hess, George R.

2016-07-01

Impervious surfaces degrade urban water quality, but their over-coverage has not explained the persistent water quality variation observed among catchments with similar rates of imperviousness. Land-cover patterns likely explain much of this variation, although little is known about how they vary among watersheds. Our goal was to analyze a series of urban catchments within a range of impervious cover to evaluate how land-cover varies among them. We then highlight examples from the literature to explore the potential effects of land-cover pattern variability for urban watershed management. High-resolution (1 m2) land-cover data were used to quantify 23 land-cover pattern and stormwater infrastructure metrics within 32 catchments across the Triangle Region of North Carolina. These metrics were used to analyze variability in land-cover patterns among the study catchments. We used hierarchical clustering to organize the catchments into four groups, each with a distinct landscape pattern. Among these groups, the connectivity of combined land-cover patches accounted for 40 %, and the size and shape of lawns and buildings accounted for 20 %, of the overall variation in land-cover patterns among catchments. Storm water infrastructure metrics accounted for 8 % of the remaining variation. Our analysis demonstrates that land-cover patterns do vary among urban catchments, and that trees and grass (lawns) are divergent cover types in urban systems. The complex interactions among land-covers have several direct implications for the ongoing management of urban watersheds.

Linking river nutrient concentrations to land use and rainfall in a paddy agriculture-urban area gradient watershed in southeast China.

PubMed

Xia, Yongqiu; Ti, Chaopu; She, Dongli; Yan, Xiaoyuan

2016-10-01

The effects of land use and land-use changes on river nutrient concentrations are not well understood, especially in the watersheds of developing countries that have a mixed land use of rice paddy fields and developing urban surfaces. Here, we present a three-year study of a paddy agricultural-urban area gradient watershed in southeast China. The annual anthropogenic nitrogen (N) input from the agricultural region to the urban region was high, yet the results showed that the monthly nutrient concentrations in the river were low in the rainy seasons. The nutrient concentrations decreased continuously as the river water passed through the traditional agriculture region (TAR; paddy rice and wheat rotation) and increased substantially in the city region (CR). The traditional agricultural reference region exported most of the nutrient loads at high flows (>1mmd(-1)), the intensified agricultural region (IAR, aquaculture and poultry farming) exported most of the nutrient loads at moderate flows (between 0.5 and 1mmd(-1)), and the CR reference area exported most of the nutrient loads under low to moderate flows. We developed a statistical model to link variations in the nutrient concentrations to the proportion of land-use types and rainfall. The statistical results showed that impervious surfaces, which we interpret as a proxy for urban activities including sewage disposal, were the most important drivers of nutrient concentrations, whereas water surfaces accounted for a substantial proportion of the nutrient sinks. Therefore, to efficiently reduce water pollution, sewage from urban areas must be addressed as a priority, although wetland restoration could also achieve substantial pollutant removal. Copyright © 2016. Published by Elsevier B.V.

Modelling heavy metals build-up on urban road surfaces for effective stormwater reuse strategy implementation.

PubMed

Hong, Nian; Zhu, Panfeng; Liu, An

2017-12-01

Urban road stormwater is an alternative water resource to mitigate water shortage issues in the worldwide. Heavy metals deposited (build-up) on urban road surface can enter road stormwater runoff, undermining stormwater reuse safety. As heavy metal build-up loads perform high variabilities in terms of spatial distribution and is strongly influenced by surrounding land uses, it is essential to develop an approach to identify hot-spots where stormwater runoff could include high heavy metal concentrations and hence cannot be reused if it is not properly treated. This study developed a robust modelling approach to estimating heavy metal build-up loads on urban roads using land use fractions (representing percentages of land uses within a given area) by an artificial neural network (ANN) model technique. Based on the modelling results, a series of heavy metal load spatial distribution maps and a comprehensive ecological risk map were generated. These maps provided a visualization platform to identify priority areas where the stormwater can be safely reused. Additionally, these maps can be utilized as an urban land use planning tool in the context of effective stormwater reuse strategy implementation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gray Wave of the Great Transformation: A Satellite View of Urbanization, Climate Change, and Food Security

NASA Technical Reports Server (NTRS)

Imhoff, Marc Lee; Kamiell, Arnon Menahem

2010-01-01

Land cover change driven by human activity is profoundly affecting Earth's natural systems with impacts ranging from a loss of biological diversity to changes in regional and global climate. This change has been so pervasive and progressed so rapidly, compared to natural processes, scientists refer to it as "the great transformation". Urbanization or the 'gray wave' of land transformation is being increasingly recognized as an important process in global climate change. A hallmark of our success as a species, large urban conglomerates do in fact alter the land surface so profoundly that both local climate and the basic ecology of the landscape are affected in ways that have consequences to human health and economic well-being. Fortunately we have incredible new tools for planning and developing urban places that are both enjoyable and sustainable. A suite of Earth observing satellites is making it possible to study the interactions between urbanization, biological processes, and weather and climate. Using these Earth Observatories we are learning how urban heat islands form and potentially ameliorate them, how urbanization can affect rainfall, pollution, and surface water recharge at the local level and climate and food security globally.

Neighborhood Landscape Spatial Patterns and Land Surface Temperature: An Empirical Study on Single-Family Residential Areas in Austin, Texas.

PubMed

Kim, Jun-Hyun; Gu, Donghwan; Sohn, Wonmin; Kil, Sung-Ho; Kim, Hwanyong; Lee, Dong-Kun

2016-09-02

Rapid urbanization has accelerated land use and land cover changes, and generated the urban heat island effect (UHI). Previous studies have reported positive effects of neighborhood landscapes on mitigating urban surface temperatures. However, the influence of neighborhood landscape spatial patterns on enhancing cooling effects has not yet been fully investigated. The main objective of this study was to assess the relationships between neighborhood landscape spatial patterns and land surface temperatures (LST) by using multi-regression models considering spatial autocorrelation issues. To measure the influence of neighborhood landscape spatial patterns on LST, this study analyzed neighborhood environments of 15,862 single-family houses in Austin, Texas, USA. Using aerial photos, geographic information systems (GIS), and remote sensing, FRAGSTATS was employed to calculate values of several landscape indices used to measure neighborhood landscape spatial patterns. After controlling for the spatial autocorrelation effect, results showed that larger and better-connected landscape spatial patterns were positively correlated with lower LST values in neighborhoods, while more fragmented and isolated neighborhood landscape patterns were negatively related to the reduction of LST.

Neighborhood Landscape Spatial Patterns and Land Surface Temperature: An Empirical Study on Single-Family Residential Areas in Austin, Texas

PubMed Central

Kim, Jun-Hyun; Gu, Donghwan; Sohn, Wonmin; Kil, Sung-Ho; Kim, Hwanyong; Lee, Dong-Kun

2016-01-01

Rapid urbanization has accelerated land use and land cover changes, and generated the urban heat island effect (UHI). Previous studies have reported positive effects of neighborhood landscapes on mitigating urban surface temperatures. However, the influence of neighborhood landscape spatial patterns on enhancing cooling effects has not yet been fully investigated. The main objective of this study was to assess the relationships between neighborhood landscape spatial patterns and land surface temperatures (LST) by using multi-regression models considering spatial autocorrelation issues. To measure the influence of neighborhood landscape spatial patterns on LST, this study analyzed neighborhood environments of 15,862 single-family houses in Austin, Texas, USA. Using aerial photos, geographic information systems (GIS), and remote sensing, FRAGSTATS was employed to calculate values of several landscape indices used to measure neighborhood landscape spatial patterns. After controlling for the spatial autocorrelation effect, results showed that larger and better-connected landscape spatial patterns were positively correlated with lower LST values in neighborhoods, while more fragmented and isolated neighborhood landscape patterns were negatively related to the reduction of LST. PMID:27598186

Time series decomposition of remotely sensed land surface temperature and investigation of trends and seasonal variations in surface urban heat islands

NASA Astrophysics Data System (ADS)

Quan, Jinling; Zhan, Wenfeng; Chen, Yunhao; Wang, Mengjie; Wang, Jinfei

2016-03-01

Previous time series methods have difficulties in simultaneous characterization of seasonal, gradual, and abrupt changes of remotely sensed land surface temperature (LST). This study proposed a model to decompose LST time series into trend, seasonal, and noise components. The trend component indicates long-term climate change and land development and is described as a piecewise linear function with iterative breakpoint detection. The seasonal component illustrates annual insolation variations and is modeled as a sinusoidal function on the detrended data. This model is able to separate the seasonal variation in LST from the long-term (including gradual and abrupt) change. Model application to nighttime Moderate Resolution Imaging Spectroradiometer (MODIS)/LST time series during 2000-2012 over Beijing yielded an overall root-mean-square error of 1.62 K between the combination of the decomposed trend and seasonal components and the actual MODIS/LSTs. LST decreased (~ -0.086 K/yr, p < 0.1) in 53% of the study area, whereas it increased with breakpoints in 2009 (~0.084 K/yr before and ~0.245 K/yr after 2009) between the fifth and sixth ring roads. The decreasing trend was stronger over croplands than over urban lands (p < 0.05), resulting in an increasing trend in surface urban heat island intensity (SUHII, 0.022 ± 0.006 K/yr). This was mainly attributed to the trends in urban-rural differences in rainfall and albedo. The SUHII demonstrated a concave seasonal variation primarily due to the seasonal variations of urban-rural differences in temperature cooling rate (related to canyon structure, vegetation, and soil moisture) and surface heat dissipation (affected by humidity and wind).

Examples of Level Products Possible from Existing Assets

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.

2012-01-01

How do patterns of human environmental and infectious diseases respond to leading environmental changes, particularly to urban growth and change and the associated impacts of urbanization? We use HyspIRI high spatial resolution, multispectral, and multitemporal TIR data to track energy balance and energy flux characteristics for changing land covers/land uses through time to provide synoptic views of impacts on surface energy fluxes, emissivity and temperature and HyspIRI data in conjunction with spatial growth models to project land cover/land use changes in the future to assess impacts on natural and human ecosystems. We use multispectral thermal IR land cover maps at a high spatial resolution (60m) on a weekly basis for long-term validation of surface energy responses and changes in emissivity and integration of HyspIRI TIR data with spatial modeling to assess changes in land cover/land use through time and subsequent changes in thermal energy responses

Earth Observation in Support of Sustainable Urban Planning: Results of the Dragon-3 Monitor Project

NASA Astrophysics Data System (ADS)

Cartalis, C.; Polydoros, A.; Mavrakou, T.; Asimakopoulos, D. N.

2016-08-01

Sustainable urban planning increasingly demands innovative concepts and techniques to obtain up-to-date and area-wide information on the characteristics and development of the urban system. In this paper, a thorough and conclusive presentation is made in terms of the results of the DRAGON-3 MONITOR project as based on the use of Earth Observation. Results refer in particular to a set of EO based dynamic urban indicators (i.e. urban form and expansion, land use/land cover changes, land surface temperature distribution, the presence and strength of urban heat island) with the capacity to describe the state, dynamic changes and interaction of the land and thermal environment in urban areas. Furthermore results are assessed in terms of their potential to operationally support sustainable urban planning and bridge the gap between EO scientists and urban planners. Constraints related to the spatial resolution and revisit time of satellite sensors are discussed as they influence the accuracy and applicability of the indicators. Methodologies to improve the applicability of the indicators are also discussed along with the presentation of the respective results.

Total mercury and methylmercury in fish fillets, water, and bed sediments from selected streams in the Delaware River basin, New Jersery, New York, and Pennsylvania, 1998-2001

USGS Publications Warehouse

Brightbill, Robin A.; Riva-Murray, Karen; Bilger, Michael D.; Byrnes, John D.

2004-01-01

Within the Delaware River Basin, fish-tissue samples were analyzed for total mercury (tHg). Water and bed-sediment samples were analyzed for tHg and methylmercury (MeHg), and methylation efficiencies were calculated. This study was part of a National Mercury Pilot Program conducted by the U.S. Geological Survey (USGS). The Delaware River Basin was chosen because it is part of the USGS National Water-Quality Assessment Program that integrates physical, chemical, and biological sampling efforts to determine status and trends in surface-water and ground-water resources. Of the 35 sites in the study, 31 were sampled for fish. The species sampled at these sites include smallmouth bass (Micropterus dolomieu), the target species, and where smallmouth bass could not be collected, brown trout (Salmo trutta), chain pickerel (Esox niger), largemouth bass (Micropterus salmoides), and rock bass (Ambloplites rupestris). There were a total of 32 fish samples; 7 of these exceeded the 0.3 ?g/g (micrograms per gram) wet-weight mercury (Hg) concentration set for human health by the U.S. Environmental Protection Agency and 27 of these exceeded the U.S. Fish and Wildlife Service criteria of 0.1 ?g/g wet weight for the protection of fish-eating birds and wildlife. Basinwide analysis of Hg in fish, water, and bed sediment showed tHg concentration in fillets correlated positively with population density, urban land cover, and impervious land surface. Negative correlations included wetland land cover, septic density, elevation, and latitude. Smallmouth bass from the urban sites had a higher median concentration of tHg than fish from agricultural, low intensity-agricultural, or forested sites. Concentrations of tHg and MeHg in water were higher in samples from the more urbanized areas of the basin and were positively correlated with urbanization and negatively correlated with forested land cover. Methylation efficiency of water was negatively correlated with urbanization. Bed-sediment patterns were similar to those observed in water. Concentrations of tHg were higher in samples from the urbanized areas. In the more forested areas, MeHg concentrations were higher than in other land-use areas. Concentrations of tHg in bed sediment were positively correlated with urbanization factors (population, urban land cover, and impervious land surface) and negatively correlated with forested land cover and elevation. Forested land cover and latitude were positively correlated with concentrations of MeHg. The methylation efficiency was higher in samples from the forested areas and was negatively correlated with urbanization. Analyses within land-use groups showed that tHg concentrations in fish fillets from the urban sites were positively correlated with forested land cover and wetland cover. Urbanization factors within the agricultural group were positively correlated with tHg in fish; concentrations of tHg in fish from sites in the low intensity-agricultural group were negatively correlated with urbanization factors. Within the agricultural land-use group, tHg concentrations in water were negatively correlated with septic density, and MeHg concentrations were negatively correlated with elevation. In the forested and low intensity-agricultural groups, MeHg in water was negatively correlated with forested and agricultural land cover. Methylation efficiency in water also was negatively correlated with forested land cover but positively correlated with agricultural land cover. Bed sediment concentrations of tHg in the forested and low-agricultural groups were positively correlated with agricultural land cover and negatively correlated with forested land cover. Concentrations of MeHg in bed sediment were positively correlated with septic density and drainage area and negatively correlated with forested land cover. Methylation efficiency was negatively correlated with population density, a

Impacts of Urbanization in the Coastal Tropical City of San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Comarazamy, Daniel E.; Gonzalez, Jorge E.; Luvall, Jeffrey C.; Rickman, Douglass

2007-01-01

Urban sprawl in tropical locations is rapidly accelerating and it is more evident in islands where a large percentage of the population resides along the coasts. This paper focuses on the analysis of the impacts of land use and land cover for urbanization in the tropical coastal city of San Juan, in the Caribbean island of Puerto Rico. A mesoscale numerical model, the Regional Atmospheric Modeling System (RAMS), is used to study the impacts of land use for urbanization in the environment including specific characteristics of the urban heat island in the San Juan Metropolitan Area (SJMA), one of the most noticeable urban cores of the Caribbean. The research also makes use of the observations obtained during the airborne San Juan Atlas Mission. Surface and raw insonde data from the mission are used to validate the atmospheric model yielding satisfactory results. Airborne high resolution remote sensing data are used to update the model's surface characteristics in order to obtain a more accurate and detailed configuration of the SJMA and perform a climate impact analysis based on land cover/land use (LCLU) changes. The impact analysis showed that the presence of the urban landscape of San Juan has an impact reflected in higher air temperatures over the area occupied by the city, with positive values of up to 2.5 degrees C, for the simulations that have specified urban LCLU indexes in the model's bottom boundary. One interesting result of the impact analysis was the finding of a precipitation disturbance shown as a difference in total accumulated rainfall between the present urban landscape and with a potential natural vegetation, apparently induced by the presence of the urban area. Results indicate that the urban-enhanced cloud formation and precipitation development occur mainly downwind of the city, including the accumulated precipitation. This spatial pattern can be explained by the presence of a larger urbanized area in the southwest sector of the city, and of the approaching northeasterly trade winds.

Evaluation of an urban land surface scheme over a tropical suburban neighborhood

NASA Astrophysics Data System (ADS)

Harshan, Suraj; Roth, Matthias; Velasco, Erik; Demuzere, Matthias

2017-07-01

The present study evaluates the performance of the SURFEX (TEB/ISBA) urban land surface parametrization scheme in offline mode over a suburban area of Singapore. Model performance (diurnal and seasonal characteristics) is investigated using measurements of energy balance fluxes, surface temperatures of individual urban facets, and canyon air temperature collected during an 11-month period. Model performance is best for predicting net radiation and sensible heat fluxes (both are slightly overpredicted during daytime), but weaker for latent heat (underpredicted during daytime) and storage heat fluxes (significantly underpredicted daytime peaks and nighttime storage). Daytime surface temperatures are generally overpredicted, particularly those containing horizontal surfaces such as roofs and roads. This result, together with those for the storage heat flux, point to the need for a better characterization of the thermal and radiative characteristics of individual urban surface facets in the model. Significant variation exists in model behavior between dry and wet seasons, the latter generally being better predicted. The simple vegetation parametrization used is inadequate to represent seasonal moisture dynamics, sometimes producing unrealistically dry conditions.

Quantifying the contribution of land use change to surface temperature in the lower reaches of the Yangtze River

NASA Astrophysics Data System (ADS)

Wang, Xueqian; Guo, Weidong; Qiu, Bo; Liu, Ye; Sun, Jianning; Ding, Aijun

2017-04-01

Anthropogenic land use has a significant impact on climate change. Located in the typical East Asian monsoon region, the land-atmosphere interaction in the lower reaches of the Yangtze River is even more complicated due to intensive human activities and different types of land use in this region. To better understand these effects on microclimate change, we compare differences in land surface temperature (Ts) for three land types around Nanjing from March to August, 2013, and then quantify the contribution of land surface factors to these differences (ΔTs) by considering the effects of surface albedo, roughness length, and evaporation. The atmospheric background contribution to ΔTs is also considered based on differences in air temperature (ΔTa). It is found that the cropland cooling effect decreases Ts by 1.76° and the urban heat island effect increases Ts by 1.25°. They have opposite impacts but are both significant in this region. Various changes in surface factors affect radiation and energy distribution and eventually modify Ts. It is the evaporative cooling effect that plays the most important role in this region and accounts for 1.40° of the crop cooling and 2.29° of the urban warming. Moreover, the background atmospheric circulation is also an indispensable part in land-atmosphere feedback induced by land use change and reinforces both these effects.

Seasonal temperature responses to land-use change in the western United States

USGS Publications Warehouse

Kueppers, L.M.; Snyder, M.A.; Sloan, L.C.; Cayan, D.; Jin, J.; Kanamaru, H.; Kanamitsu, M.; Miller, N.L.; Tyree, Mary; Du, H.; Weare, B.

2008-01-01

In the western United States, more than 79 000??km2 has been converted to irrigated agriculture and urban areas. These changes have the potential to alter surface temperature by modifying the energy budget at the land-atmosphere interface. This study reports the seasonally varying temperature responses of four regional climate models (RCMs) - RSM, RegCM3, MM5-CLM3, and DRCM - to conversion of potential natural vegetation to modern land-cover and land-use over a 1-year period. Three of the RCMs supplemented soil moisture, producing large decreases in the August mean (- 1.4 to - 3.1????C) and maximum (- 2.9 to - 6.1????C) 2-m air temperatures where natural vegetation was converted to irrigated agriculture. Conversion to irrigated agriculture also resulted in large increases in relative humidity (9% to 36% absolute change). Modeled changes in the August minimum 2-m air temperature were not as pronounced or consistent across the models. Converting natural vegetation to urban land-cover produced less pronounced temperature effects in all models, with the magnitude of the effect dependent upon the preexisting vegetation type and urban parameterizations. Overall, the RCM results indicate that the temperature impacts of land-use change are most pronounced during the summer months, when surface heating is strongest and differences in surface soil moisture between irrigated land and natural vegetation are largest. ?? 2007 Elsevier B.V. All rights reserved.

Climatology (communication arising): rural land-use change and climate.

PubMed

Trenberth, Kevin E

2004-01-15

Kalnay and Cai claim that urbanization and land-use change have a major effect on the climate in the United States. They used surface temperatures obtained from NCEP/NCAR 50-year reanalyses (NNR) and their difference compared with observed station surface temperatures as the basis for their conclusions, on the grounds that the NNR did not include these anthropogenic effects. However, we note that the NNR also overlooked other factors, such as known changes in clouds and in surface moisture, which are more likely to explain Kalnay and Cai's findings. Although urban heat-island effects are real in cities, direct estimates of the effects of rural land-use change indicate a cooling rather than a warming influence that is due to a greater reflection of sunlight.

Climatology (communication arising): Rural land-use change and climate

NASA Astrophysics Data System (ADS)

Trenberth, Kevin E.

2004-01-01

Kalnay and Cai claim that urbanization and land-use change have a major effect on the climate in the United States. They used surface temperatures obtained from NCEP/NCAR 50-year reanalyses (NNR) and their difference compared with observed station surface temperatures as the basis for their conclusions, on the grounds that the NNR did not include these anthropogenic effects. However, we note that the NNR also overlooked other factors, such as known changes in clouds and in surface moisture, which are more likely to explain Kalnay and Cai's findings. Although urban heat-island effects are real in cities, direct estimates of the effects of rural land-use change indicate a cooling rather than a warming influence that is due to a greater reflection of sunlight.

Potential Impacts of Urban Land Expansion on Asian Outflows of Air Pollutants

NASA Astrophysics Data System (ADS)

Wei, T.; Liu, J.; Tao, S.; Ban-Weiss, G. A.

2016-12-01

We investigate the impacts of urban land expansion over Eastern China (EC) on the export of black carbon (BC), carbon monoxide (CO) and ozone (O3) to the West Pacific during the January, April, July and October of 2009, using WRF/Chem model coupled with the tracers tagging technique and an up-to-date single layer urban canopy scheme updated with the treatment of urban hydrological processes. Our model simulations could reproduce well the vertical profiles of Asian outflows of BC and CO observed during the A-FORCE period (March to April of 2009). Over urbanizing areas, increment in urban land fraction could linearly elevate primary pollutants from the lower boundary layer to higher altitudes, and perturb the thermal, hydrological, and kinetic exchange processes between land surface and the atmosphere aloft through all seasons (such local impacts highest in July but lowest in January). Furthermore, we find robust linear relationships exist between urban land fraction (averaged over EC) and export of BC emitted from EC across meridional planes over the western Pacific (e.g., 140 °E). Specifically, each 10% increase in urban land fraction over EC enhances the eastward mass fluxes of BC by about 5%-10% in January and July, and 10%-20% in April and October, respectively, in the free troposphere, which is the dominant pathway for Asian outflows. Such a linear relationship is relatively weaker for CO and only appears in April and October. The different response patterns between BC and CO arise from their distinct physical and chemical properties. Even with decreased vegetation (and reduced biogenic emissions), the O3­ concentrations at the surface and 800 hPa over urbanizing areas both tend to increase. However, no clear trend is observed for the export of O3 over West Pacific for all four months. Urban land expansion facilitates the uplift of local pollutants, but also changes the large-scale circulation pattern (the perturbation cyclone over the downwind Pacific acts to impede the eastward transpacific transport), both playing important roles on the efficiency that Asian emissions are exported. Our finding indicates that the extensive urban land expansion would significantly impact the local climate and air quality, which also have a large impact on long-range transboundary transport.

Effect of land cover and green space on land surface temperature of a fast growing economic region in Malaysia

NASA Astrophysics Data System (ADS)

Sheikhi, A.; Kanniah, K. D.; Ho, C. H.

2015-10-01

Green space must be increased in the development of new cities as green space can moderate temperature in the cities. In this study we estimated the land surface temperature (LST) and established relationships between LST and land cover and various vegetation and urban surface indices in the Iskandar Malaysia (IM) region. IM is one of the emerging economic gateways of Malaysia, and is envisaged to transform into a metropolis by 2025. This change may cause increased temperature in IM and therefore we conducted a study by using Landsat 5 image covering the study region (2,217 km2) to estimate LST, classify different land covers and calculate spectral indices. Results show that urban surface had highest LST (24.49 °C) and the lowest temperature was recorded in, forest, rubber and water bodies ( 20.69 to 21.02°C). Oil palm plantations showed intermediate mean LST values with 21.65 °C. We further investigated the relationship between vegetation and build up densities with temperature. We extracted 1000 collocated pure pixels of Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Built-up Index (NDBI), Urban Index (UI) and LST in the study area. Results show a strong and significant negative correlation with (R2= -0.74 and -0.79) respectively between NDVI, NDWI and LST . Meanwhile a strong positive correlation (R2=0.8 and 0.86) exists between NDBI, UI and LST. These results show the importance of increasing green cover in urban environment to combat any adverse effects of climate change.

Restoring the hydrologic response to pre-developed conditions in an urbanized headwater catchment: Reality or utopia?

NASA Astrophysics Data System (ADS)

Wright, O.; Istanbulluoglu, E.

2012-12-01

The conversion of forested areas to impervious surfaces, lawns and pastures alters the natural hydrology of an area by increasing the flashiness of stormwater generated runoff, resulting in increased streamflow peaks and volumes. Currently, most of the stormwater from developed areas in the Puget Sound region remains uncontrolled. The lack of adequate stormwater facilities along with increasing urbanization and population growth illustrates the importance of understanding urban watershed behavior and best management practices (BMPs) that improve changes in hydrology. In this study, we developed a lumped urban ecohydrology model that represents vegetation dynamics, connects pervious and impervious surfaces and implements various BMP scenarios. The model is implemented in an urban headwater subcatchment located in the Newaukum Creek Basin. We evaluate the hydrologic impact of controlling runoff at the source and disconnecting impervious surfaces from the storm drain using rain barrels and bioretention cells. BMP scenarios consider the basin's land use/land coverage, the response of different impervious surface types, the potential for BMP placement, the size and drainage area for BMPs, and the mitigation needs to meet in-stream flow goals.

Quantifying the impact of human activity on temperatures in Germany

NASA Astrophysics Data System (ADS)

Benz, Susanne A.; Bayer, Peter; Blum, Philipp

2017-04-01

Human activity directly influences ambient air, surface and groundwater temperatures. Alterations of surface cover and land use influence the ambient thermal regime causing spatial temperature anomalies, most commonly heat islands. These local temperature anomalies are primarily described within the bounds of large and densely populated urban settlements, where they form so-called urban heat islands (UHI). This study explores the anthropogenic impact not only for selected cities, but for the thermal regime on a countrywide scale, by analyzing mean annual temperature datasets in Germany in three different compartments: measured surface air temperature (SAT), measured groundwater temperature (GWT), and satellite-derived land surface temperature (LST). As a universal parameter to quantify anthropogenic heat anomalies, the anthropogenic heat intensity (AHI) is introduced. It is closely related to the urban heat island intensity, but determined for each pixel (for satellite-derived LST) or measurement point (for SAT and GWT) of a large, even global, dataset individually, regardless of land use and location. Hence, it provides the unique opportunity to a) compare the anthropogenic impact on temperatures in air, surface and subsurface, b) to find main instances of anthropogenic temperature anomalies within the study area, in this case Germany, and c) to study the impact of smaller settlements or industrial sites on temperatures. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1 km × 1 km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5 K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities > 4 K. Overall, surface anthropogenic heat intensities > 0 K and therefore urban heat islands are observed in communities down to a population of 5,000.

[Occurrence and spatial differentiation of polycyclic aromatic hydrocarbons in surface soils from Shenzhen, China].

PubMed

Zhang, Di; Cao, Shan-Ping; Sun, Jian-Lin; Zeng, Hui

2014-02-01

188 surface soil samples were collected in Shenzhen of China to determine the occurrence and spatial differentiation of polycyclic aromatic hydrocarbons (PAHs), based on which we studied the correlation between PAHs concentrations and urbanization levels, as well as the PAHs ecological risk. The total concentrations of 28 PAHs (sigma28 PAHs), 16 EPA PAHs (sigma 16 PAHs) and 7 carcinogenic PAHs (sigma7 CarPAHs) ranged from 5 to 7939 ng x g(-1), 2 to 6745 ng x g(-1) and not detected to 3786 ng x g(-1), respectively. 8 kinds of land use types according to sigma16 PAHs average levels in descending order were: transportation lands, commercial lands, industrial lands, agricultural lands, residential lands, urban green space, orchards and woodland. And sigma16 PAHs of construction and non-construction lands samples were mainly derived from combustion of various fossil fuels with contribution of 75.1% and 68.2%, respectively. Significant positive correlation was also found between PAHs concentrations of high molecular weight and urbanization levels. And PAHs pollution in the top soils of Shenzhen was at a low-end level of the world.

Characteristics of Surface Urban Heat Island (SUHI) over the Gangetic Plain of Bihar, India

NASA Astrophysics Data System (ADS)

Barat, Archisman; Kumar, Sunny; Kumar, Praveen; Parth Sarthi, P.

2018-05-01

The rapid urbanisation impacts on environment, climate, agriculture, water resources trigger several problems to human beings. The present study is carried out to estimate intensity and trend of Urban Heat Island (UHI) as Surface UHI (SUHI) over towns/cities of the Gangetic plain of the state of Bihar, India, in which urban areas show relatively greater Land Surface Temperature (LST) than its rural surroundings especially during night times. The LST data (2001-14) of Moderate Resolution Imaging Spectroradiometer (MODIS) is used for five major towns/cities of Bihar namely, Bhagalpur, Gaya, Patna, Purnea and Muzzaffarpur. Each city is classified into Urban, Suburban and Rural zones as per land cover of the area. During winter months (January, February, November and December), UHI is more intense over all towns/cities. Mann-Kendall Test is applied on Surface Urban Heat Island Intensity (SUHII) in which MK-Test Statistic (S) shows a significant increasing trend. This trend would alarm a risk to increase in air pollution, heat related biohazards, energy demand in the region. This study shows the need of urban greening and proper town planning over the considered areas to mitigate the changes.

Effects of urban form on the urban heat island effect based on spatial regression model.

PubMed

Yin, Chaohui; Yuan, Man; Lu, Youpeng; Huang, Yaping; Liu, Yanfang

2018-09-01

The urban heat island (UHI) effect is becoming more of a concern with the accelerated process of urbanization. However, few studies have examined the effect of urban form on land surface temperature (LST) especially from an urban planning perspective. This paper used spatial regression model to investigate the effects of both land use composition and urban form on LST in Wuhan City, China, based on the regulatory planning management unit. Landsat ETM+ image data was used to estimate LST. Land use composition was calculated by impervious surface area proportion, vegetated area proportion, and water proportion, while urban form indicators included sky view factor (SVF), building density, and floor area ratio (FAR). We first tested for spatial autocorrelation of urban LST, which confirmed that a traditional regression method would be invalid. A spatial error model (SEM) was chosen because its parameters were better than a spatial lag model (SLM). The results showed that urban form metrics should be the focus for mitigation efforts of UHI effects. In addition, analysis of the relationship between urban form and UHI effect based on the regulatory planning management unit was helpful for promoting corresponding UHI effect mitigation rules in practice. Finally, the spatial regression model was recommended to be an appropriate method for dealing with problems related to the urban thermal environment. Results suggested that the impact of urbanization on the UHI effect can be mitigated not only by balancing various land use types, but also by optimizing urban form, which is even more effective. This research expands the scientific understanding of effects of urban form on UHI by explicitly analyzing indicators closely related to urban detailed planning at the level of regulatory planning management unit. In addition, it may provide important insights and effective regulation measures for urban planners to mitigate future UHI effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Mapping and analyzing change of impervious surface for two decades using multi-temporal Landsat imagery in Missouri

NASA Astrophysics Data System (ADS)

Zhou, Bo; He, Hong S.; Nigh, Timothy A.; Schulz, John H.

2012-08-01

Human population growth and associated sprawl has rapidly converted open lands to developed use and affected their distinctive ecological characteristics. Missouri reflects a full range of sprawl characteristics that include large metropolitan centers, which led growth in 1980s, and smaller metropolitan and rural areas, which led growth in 1990s. In order to study the historical patterns of sprawl, there is a need to quantitatively and geographically depict the extent and density of impervious surface for three time periods of 1980, 1990, and 2000 for the entire state of Missouri. We mapped impervious surface using Sub-pixel Classifier™, an add-on module of Erdas Imagine for the three time periods, where impervious surface growth was derived as the subtraction of impervious surface mapped from the different time periods. Accuracy assessment was performed by comparing satellite derived impervious surface images with ground-truth acquired from high resolution air photos. Results show that during 1980-2000, 129,853 ha of land were converted to impervious surface. Sprawl was prominent on urban fringe (within the urban boundaries) during 1980s with 23,674 ha of land converted to impervious surface compared to 22,918 ha in 1990s. There was a temporal shift in the rural landscapes (outside the urban boundaries) in the 1990s with 48,079 ha of land converted to impervious surface compared to 35,180 ha in 1980s. Major findings based on analysis of the impervious surface growth include: (i) new growth of impervious surfaces are concentrated on areas with 0.5-1.0% road cover; (ii) most new growths are either inside or close to urban watersheds; and (iii) most new growths are either inside or close to counties with metropolitan cities. This research goes beyond the usual hot spots of metropolitan areas to include rural landscapes where negative impact was exerted to the ecosystem due to the low density development and larger affected areas.

How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis.

PubMed

Xu, Min; He, Chunyang; Liu, Zhifeng; Dou, Yinyin

2016-01-01

Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth-infilling, edge expansion, and leapfrog-edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China.

How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis

PubMed Central

Xu, Min; He, Chunyang; Liu, Zhifeng; Dou, Yinyin

2016-01-01

Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth—infilling, edge expansion, and leapfrog—edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China. PMID:27144589

A Study of Land Surface Temperature Retrieval and Thermal Environment Distribution Based on Landsat-8 in Jinan City

NASA Astrophysics Data System (ADS)

Dong, Fang; Chen, Jian; Yang, Fan

2018-01-01

Based on the medium resolution Landsat 8 OLI/TIRS, the temperature distribution in four seasons of urban area in Jinan City was obtained by using atmospheric correction method for the retrieval of land surface temperature. Quantitative analysis of the spatio-temporal distribution characteristics, development trend of urban thermal environment, the seasonal variation and the relationship between surface temperature and normalized difference vegetation index (NDVI) was studied. The results show that the distribution of high temperature areas is concentrated in Jinan, and there is a tendency to expand from east to west, revealing a negative correlation between land surface temperature distribution and NDVI. So as to provide theoretical references and scientific basis of improving the ecological environment of Jinan City, strengthening scientific planning and making overall plan addressing climate change.

São Paulo urban heat islands have a higher incidence of dengue than other urban areas.

PubMed

Araujo, Ricardo Vieira; Albertini, Marcos Roberto; Costa-da-Silva, André Luis; Suesdek, Lincoln; Franceschi, Nathália Cristina Soares; Bastos, Nancy Marçal; Katz, Gizelda; Cardoso, Vivian Ailt; Castro, Bronislawa Ciotek; Capurro, Margareth Lara; Allegro, Vera Lúcia Anacleto Cardoso

2015-01-01

Urban heat islands are characterized by high land surface temperature, low humidity, and poor vegetation, and considered to favor the transmission of the mosquito-borne dengue fever that is transmitted by the Aedes aegypti mosquito. We analyzed the recorded dengue incidence in Sao Paulo city, Brazil, in 2010-2011, in terms of multiple environmental and socioeconomic variables. Geographical information systems, thermal remote sensing images, and census data were used to classify city areas according to land surface temperature, vegetation cover, population density, socioeconomic status, and housing standards. Of the 7415 dengue cases, a majority (93.1%) mapped to areas with land surface temperature >28°C. The dengue incidence rate (cases per 100,000 inhabitants) was low (3.2 cases) in high vegetation cover areas, but high (72.3 cases) in low vegetation cover areas where the land surface temperature was 29±2°C. Interestingly, a multiple cluster analysis phenogram showed more dengue cases clustered in areas of land surface temperature >32°C, than in areas characterized as low socioeconomic zones, high population density areas, or slum-like areas. In laboratory experiments, A. aegypti mosquito larval development, blood feeding, and oviposition associated positively with temperatures of 28-32°C, indicating these temperatures to be favorable for dengue transmission. Thus, among all the variables studied, dengue incidence was most affected by the temperature. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

A study of the utilization of ERTS-1 data from the Wabash River Basin

NASA Technical Reports Server (NTRS)

Landgrebe, D. A. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Nine projects are defined, five ERTS data applications experiments and four supporting technology tasks. The most significant applications results were achieved in the soil association mapping, earth surface feature identification, and urban land use mapping efforts. Four soil association boundaries were accurately delineated from ERTS-1 imagery. A data bank has been developed to test surface feature classifications obtained from ERTS-1 data. Preliminary forest cover classifications indicated that the number of acres estimated tended to be greater than actually existed by 25%. Urban land use analysis of ERTS-1 data indicated highly accurate classification could be obtained for many urban catagories. The wooded residential category tended to be misclassified as woods or agricultural land. Further statistical analysis revealed that these classes could be separated using sample variance.

Projected Impact of Urban Growth on Climate Change

NASA Astrophysics Data System (ADS)

Amato, Federico; Murgante, Beniamino; Martellozzo, Federico

2017-04-01

Human activities on land use such as intensive agricultural techniques and urbanization are generating a number of social and economic benefit for contemporary society. Besides, these phenomena are one of the most significant causes of Land Degradation. Firstly, intensive agriculture is on the one hand creating an advantage in the short-period in terms of food production, while on the other is producing serious long-period problems in terms of loss of ecosystem services, including some important for agriculture itself. Secondly, the rapid growth of urban areas in recent decades is generating deep environmental issues. The World Urbanization Prospect by the United Nations (UN) shows that more than half of the world's population today (54%) lives in urban areas. This figure was only 30% in 1950, and estimates are that it will rise to 66% by 2050. Urban growth is responsible for the increase of air pollution, waste production, energy consumption, and land take. Moreover, the expansion of urban areas is making the problem of urban heat islands more relevant, and studies are proving how land cover changes are among the main factors that affect local microclimates. Consequently, territorial planning will play an important role in the fight to mitigate the effects of climate change, as land cover has a significant impact on the energy exchanges between the earth and the atmosphere. This study couples urban growth simulation models based on cellular automata to multiple linear regression techniques that are used to formulate equations for predicting the effects of simulated urban development on soil surface temperature. The proposed methodology is applied to the case study of the Italian national territory, considering various alternative scenarios of land use changes and of their impact on local surface temperatures. The results show that the areas with the greatest urban pressure might be subject to significant climatic changes due to the increased impact of urban heat island phenomena. This highlights the need to take meaningful action to reverse the trends currently in place concerning the territorial government, with the purpose of creating a renewed political and social context that can reduce Land Degradation phenomena. These assumptions are considered essential to meet the new climate sustainability parameters introduced by the Paris Agreement signed in December 2015.

Evaluating Water and Energy Fluxes across Three Land Cover Types in a Desert Urban Environment through a Mobile Eddy Covariance Platform

NASA Astrophysics Data System (ADS)

Pierini, N.; Vivoni, E. R.; Schreiner-McGraw, A.; Lopez-Castrillo, I.

2015-12-01

The urbanization process transforms a natural landscape into a built environment with many engineered surfaces, leading to significant impacts on surface energy and water fluxes across multiple spatial and temporal scales. Nevertheless, the effects of different urban land covers on energy and water fluxes has been rarely quantified across the large varieties of construction materials, landscaping and vegetation types, and industrial, commercial and residential areas in cities. In this study, we deployed a mobile eddy covariance tower at three different locations in the Phoenix, Arizona, metropolitan area to capture a variety of urban land covers. The three locations each represent a common urban class in Phoenix: 1) a dense, xeric landscape (gravel cover and native plants with drip-irrigation systems near tall buildings); 2) a high-density urban site (asphalt-paved parking lot near a high-traffic intersection); and 3) a suburban mesic landscape (sprinkler-irrigated turf grass in a suburban neighborhood). At each site, we measured meteorological variables, including air temperature and relative humidity at three heights, precipitation and pressure, surface temperature, and soil moisture and temperature (where applicable), to complement the eddy covariance measurements of radiation, energy, carbon dioxide and water vapor fluxes. We evaluated the tower footprint at each site to characterize the contributing surface area to the flux measurements, including engineered and landscaping elements, as a function of time for each deployment. The different sites allowed us to compare how turbulent fluxes of water vapor and carbon dioxide vary for these representative urban land covers, in particular with respect to the role of precipitation events and irrigation. While the deployments covered different seasons, from winter to summer in 2015, the variety of daily conditions allowed quantification of the differential response to precipitation events during the winter, pre-monsoon, and monsoon seasons in relation to irrigation input or lack thereof. As desert urban areas continue to grow worldwide, it is essential to gain an improved understanding of how the energy and water balances vary across the built environment and their implications on urban climate, energy, hydrologic conditions, and air quality.

Improved MODIS aerosol retrieval in urban areas using a land classification approach and empirical orthogonal functions

NASA Astrophysics Data System (ADS)

Levitan, Nathaniel; Gross, Barry

2016-10-01

New, high-resolution aerosol products are required in urban areas to improve the spatial coverage of the products, in terms of both resolution and retrieval frequency. These new products will improve our understanding of the spatial variability of aerosols in urban areas and will be useful in the detection of localized aerosol emissions. Urban aerosol retrieval is challenging for existing algorithms because of the high spatial variability of the surface reflectance, indicating the need for improved urban surface reflectance models. This problem can be stated in the language of novelty detection as the problem of selecting aerosol parameters whose effective surface reflectance spectrum is not an outlier in some space. In this paper, empirical orthogonal functions, a reconstruction-based novelty detection technique, is used to perform single-pixel aerosol retrieval using the single angular and temporal sample provided by the MODIS sensor. The empirical orthogonal basis functions are trained for different land classes using the MODIS BRDF MCD43 product. Existing land classification products are used in training and aerosol retrieval. The retrieval is compared against the existing operational MODIS 3 KM Dark Target (DT) aerosol product and co-located AERONET data. Based on the comparison, our method allows for a significant increase in retrieval frequency and a moderate decrease in the known biases of MODIS urban aerosol retrievals.

Urban Density Indices Using Mean Shift-Based Upsampled Elevetion Data

NASA Astrophysics Data System (ADS)

Charou, E.; Gyftakis, S.; Bratsolis, E.; Tsenoglou, T.; Papadopoulou, Th. D.; Vassilas, N.

2015-04-01

Urban density is an important factor for several fields, e.g. urban design, planning and land management. Modern remote sensors deliver ample information for the estimation of specific urban land classification classes (2D indicators), and the height of urban land classification objects (3D indicators) within an Area of Interest (AOI). In this research, two of these indicators, Building Coverage Ratio (BCR) and Floor Area Ratio (FAR) are numerically and automatically derived from high-resolution airborne RGB orthophotos and LiDAR data. In the pre-processing step the low resolution elevation data are fused with the high resolution optical data through a mean-shift based discontinuity preserving smoothing algorithm. The outcome is an improved normalized digital surface model (nDSM) is an upsampled elevation data with considerable improvement regarding region filling and "straightness" of elevation discontinuities. In a following step, a Multilayer Feedforward Neural Network (MFNN) is used to classify all pixels of the AOI to building or non-building categories. For the total surface of the block and the buildings we consider the number of their pixels and the surface of the unit pixel. Comparisons of the automatically derived BCR and FAR indicators with manually derived ones shows the applicability and effectiveness of the methodology proposed.

Mapping impervious surfaces using object-oriented classification in a semiarid urban region

USDA-ARS?s Scientific Manuscript database

Mapping the expansion of impervious surfaces in urbanizing areas is important for monitoring and understanding the hydrologic impacts of land development. The most common approach using spectral vegetation indices, however, is difficult in arid and semiarid environments where vegetation is sparse an...

Alterations to groundwater recharge due to anthropogenic landscape change

NASA Astrophysics Data System (ADS)

Han, Dongmei; Currell, Matthew J.; Cao, Guoliang; Hall, Benjamin

2017-11-01

The impacts of anthropogenic modifications to the landscape on groundwater recharge rates, locations, and mechanisms are reviewed. The two major categories of change examined are conversion of land for agriculture and urbanization, both of which have significant effects on groundwater recharge. Techniques for identifying and quantifying the changes in recharge due to these impacts are discussed. Land-clearing for agriculture and surface water transfer for irrigation have resulted in order of magnitude increases in recharge rates in many semi-arid regions worldwide, causing ongoing land and water salinization and water-logging problems. While increased recharge by irrigation return flow may alleviate shallow groundwater depletion in some settings, this is complicated by the effect of unsaturated zone thickening, which reduces the fraction of potential recharge becoming actual recharge, and may result in new water quality risks such as nitrate contamination. Expansion of urban and peri-urban land and their associated surface and sub-surface infrastructure results in complex water balance changes that re-distribute groundwater recharge locations, modify recharge mechanism(s) and result in variable impacts on recharge rates (e.g., overall net decrease, increase or minimal change) and quality. While changes to groundwater recharge resulting from conversion of land for agriculture are relatively well understood, less is documented about the changes resulting from urbanization, due to a paucity of data from field-based studies. Two case studies from Beijing, China and Melbourne Australia are examined, which highlight these impacts and demonstrate some potential methodological techniques for this topic.

Habitat Composition and Connectivity Predicts Bat Presence and Activity at Foraging Sites in a Large UK Conurbation

PubMed Central

Hale, James D.; Fairbrass, Alison J.; Matthews, Tom J.; Sadler, Jon P.

2012-01-01

Background Urbanization is characterized by high levels of sealed land-cover, and small, geometrically complex, fragmented land-use patches. The extent and density of urbanized land-use is increasing, with implications for habitat quality, connectivity and city ecology. Little is known about densification thresholds for urban ecosystem function, and the response of mammals, nocturnal and cryptic taxa are poorly studied in this respect. Bats (Chiroptera) are sensitive to changing urban form at a species, guild and community level, so are ideal model organisms for analyses of this nature. Methodology/Principal Findings We surveyed bats around urban ponds in the West Midlands conurbation, United Kingdom (UK). Sites were stratified between five urban land classes, representing a gradient of built land-cover at the 1 km2 scale. Models for bat presence and activity were developed using land-cover and land-use data from multiple radii around each pond. Structural connectivity of tree networks was used as an indicator of the functional connectivity between habitats. All species were sensitive to measures of urban density. Some were also sensitive to landscape composition and structural connectivity at different spatial scales. These results represent new findings for an urban area. The activity of Pipistrellus pipistrellus (Schreber 1774) exhibited a non-linear relationship with the area of built land-cover, being much reduced beyond the threshold of ∼60% built surface. The presence of tree networks appears to mitigate the negative effects of urbanization for this species. Conclusions/Significance Our results suggest that increasing urban density negatively impacts the study species. This has implications for infill development policy, built density targets and the compact city debate. Bats were also sensitive to the composition and structure of the urban form at a range of spatial scales, with implications for land-use planning and management. Protecting and establishing tree networks may improve the resilience of some bat populations to urban densification. PMID:22428015

Habitat composition and connectivity predicts bat presence and activity at foraging sites in a large UK conurbation.

PubMed

Hale, James D; Fairbrass, Alison J; Matthews, Tom J; Sadler, Jon P

2012-01-01

Urbanization is characterized by high levels of sealed land-cover, and small, geometrically complex, fragmented land-use patches. The extent and density of urbanized land-use is increasing, with implications for habitat quality, connectivity and city ecology. Little is known about densification thresholds for urban ecosystem function, and the response of mammals, nocturnal and cryptic taxa are poorly studied in this respect. Bats (Chiroptera) are sensitive to changing urban form at a species, guild and community level, so are ideal model organisms for analyses of this nature. We surveyed bats around urban ponds in the West Midlands conurbation, United Kingdom (UK). Sites were stratified between five urban land classes, representing a gradient of built land-cover at the 1 km(2) scale. Models for bat presence and activity were developed using land-cover and land-use data from multiple radii around each pond. Structural connectivity of tree networks was used as an indicator of the functional connectivity between habitats. All species were sensitive to measures of urban density. Some were also sensitive to landscape composition and structural connectivity at different spatial scales. These results represent new findings for an urban area. The activity of Pipistrellus pipistrellus (Schreber 1774) exhibited a non-linear relationship with the area of built land-cover, being much reduced beyond the threshold of ∼60% built surface. The presence of tree networks appears to mitigate the negative effects of urbanization for this species. Our results suggest that increasing urban density negatively impacts the study species. This has implications for infill development policy, built density targets and the compact city debate. Bats were also sensitive to the composition and structure of the urban form at a range of spatial scales, with implications for land-use planning and management. Protecting and establishing tree networks may improve the resilience of some bat populations to urban densification.

Characterizing the fabric of the urban environment: A case study of Greater Houston, Texas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rose, Leanna Shea; Akbari, Hashem; Taha, Haider

2003-01-15

In this report, the materials and various surface types that comprise a city are referred to as the ''urban fabric.'' Urban fabric data are needed in order to estimate the impact of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on the meteorology and air quality of a city, and to design effective urban environmental implementation programs. We discuss the results of a semi-automatic Monte-Carlo statistical approach used to develop data on surface-type distribution and city-fabric makeup (percentage of various surface-types) using aerial color orthophotography. The digital aerial photographs for Houston covered a total of about 52more » km2 (20 mi2). At 0.30-m resolution, there were approximately 5.8 x 108 pixels of data. Four major land-use types were examined: (1) commercial, (2) industrial, (3) educational, and (4) residential. On average, for the regions studied, vegetation covers about 39 percent of the area, roofs cover about 21 percent, and paved surfaces cover about 29 percent. For the most part, trees shade streets, parking lots, grass, and sidewalks. At ground level, i.e., view from below the vegetation canopies, paved surfaces cover about 32 percent of the study area. GLOBEIS model data from University of Texas and land-use/land-cover (LULC) information from the United States Geological Survey (USGS) were used to extrapolate these results from neighborhood scales to Greater Houston. It was found that in an area of roughly 3,430 km2, defining most of Greater Houston, over 56 percent is residential. The total roof area is about 740 km2, and the total paved surface area (roads, parking areas, sidewalks) covers about 1000 km2. Vegetation covers about 1,320 km2.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Yuyu; Smith, Steven J.; Zhao, Kaiguang

Urbanization, one of the major human induced land-cover and land-use changes, has a profound impact on the Earth system including biodiversity, the cycling of water and carbon and exchange of energy and water between Earth’s surface and atmosphere, all affecting weather and climate. Accurate information on urban areas and their spatial distribution at the regional and global scales is important for scientific understanding of their contribution to the changing Earth system, and for practical management and policy decisions. We developed a method to map the urban extent from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime stable-light data atmore » the global level and derived a new global map of 1-km urban extent for year 2000. Based on this map, we found that globally, urban land area is about 0.5% of total land area but ranges widely at regional level from 0.1% in Oceania to 2.3% in Europe. At the country level, urban land area varies from lower than 0.01% to higher than 10%, but is lower than 1% for most (70%) countries. Urbanization follows land mass distribution, as anticipated, with the highest concentration found between 30°N to 45°N latitude and the largest longitudinal peak around 80°W. Based on a sensitivity analysis and comparison with other global urban area products, we found that our global product of urban area provides a reliable estimate of global urban areas and offer the potential of capturing more accurately their spatial and temporal dynamics.« less

A dynamic aerodynamic resistance approach to calculate high resolution sensible heat fluxes in urban areas

NASA Astrophysics Data System (ADS)

Crawford, Ben; Grimmond, Sue; Kent, Christoph; Gabey, Andrew; Ward, Helen; Sun, Ting; Morrison, William

2017-04-01

Remotely sensed data from satellites have potential to enable high-resolution, automated calculation of urban surface energy balance terms and inform decisions about urban adaptations to environmental change. However, aerodynamic resistance methods to estimate sensible heat flux (QH) in cities using satellite-derived observations of surface temperature are difficult in part due to spatial and temporal variability of the thermal aerodynamic resistance term (rah). In this work, we extend an empirical function to estimate rah using observational data from several cities with a broad range of surface vegetation land cover properties. We then use this function to calculate spatially and temporally variable rah in London based on high-resolution (100 m) land cover datasets and in situ meteorological observations. In order to calculate high-resolution QH based on satellite-observed land surface temperatures, we also develop and employ novel methods to i) apply source area-weighted averaging of surface and meteorological variables across the study spatial domain, ii) calculate spatially variable, high-resolution meteorological variables (wind speed, friction velocity, and Obukhov length), iii) incorporate spatially interpolated urban air temperatures from a distributed sensor network, and iv) apply a modified Monte Carlo approach to assess uncertainties with our results, methods, and input variables. Modeled QH using the aerodynamic resistance method is then compared to in situ observations in central London from a unique network of scintillometers and eddy-covariance measurements.

The Complexities of Urban Flood Response: Hydrologic Analyses for the Charlotte, North Carolina Metropolitan Region

NASA Astrophysics Data System (ADS)

Zhou, Z.; Smith, J. A.; Yang, L.; Baeck, M. L.; Liu, S.; Ten Veldhuis, M. C.

2016-12-01

The objective of this study is to develop a broad characterization of land surface and hydrometeorological controls of urban flood frequency. We focus on a collection of "small" urban watersheds (with drainage area ranging from 7 to 200 km2) in Charlotte metropolitan region, North Carolina. These watersheds are contrasted by a variety of land surface properties, such as size, shape, land use/land cover type, impervious coverage pattern, stormwater infrastructure, etc. We carried out empirical analyses based on long-term (15 years), high-resolution (1 15 minutes) instantaneous USGS stream gaging observations as well as bias-corrected, high-resolution (1 km2, 15 min) radar rainfall fields developed through the Hydro-NEXRAD system. Extreme floods in Charlotte urban watersheds are primarily induced by a mixture of flood agents including warm season thunderstorms and tropical cyclones, which ultimately contributed to the upper-tail properties of flood frequency. Flood response in urban watersheds is dominantly dictated by space-time characteristics of rainfall, with relatively significant correlation between runoff and rainfall over more developed watersheds. The roles of antecedent soil moisture and stormwater management infrastructure in flood response are also contrasted across the urban watersheds. The largest variability of flood response, in terms of flood peak and timing, exists in the watershed at a scale of 100 km2. The scale-dependent hydrological response is closely related to the pattern and evolution of urban development across watersheds. Our analyses show the complexities of urban flood response in Charlotte metropolitan region. There are no simple metrics that could perfectly explain the contrasts in flood response across urban watersheds. Future research is directed towards sophisticated modeling studies for a predictive understanding of flood frequency in urban watersheds.

Impacts of land use and population density on seasonal surface water quality using a modified geographically weighted regression.

PubMed

Chen, Qiang; Mei, Kun; Dahlgren, Randy A; Wang, Ting; Gong, Jian; Zhang, Minghua

2016-12-01

As an important regulator of pollutants in overland flow and interflow, land use has become an essential research component for determining the relationships between surface water quality and pollution sources. This study investigated the use of ordinary least squares (OLS) and geographically weighted regression (GWR) models to identify the impact of land use and population density on surface water quality in the Wen-Rui Tang River watershed of eastern China. A manual variable excluding-selecting method was explored to resolve multicollinearity issues. Standard regression coefficient analysis coupled with cluster analysis was introduced to determine which variable had the greatest influence on water quality. Results showed that: (1) Impact of land use on water quality varied with spatial and seasonal scales. Both positive and negative effects for certain land-use indicators were found in different subcatchments. (2) Urban land was the dominant factor influencing N, P and chemical oxygen demand (COD) in highly urbanized regions, but the relationship was weak as the pollutants were mainly from point sources. Agricultural land was the primary factor influencing N and P in suburban and rural areas; the relationship was strong as the pollutants were mainly from agricultural surface runoff. Subcatchments located in suburban areas were identified with urban land as the primary influencing factor during the wet season while agricultural land was identified as a more prevalent influencing factor during the dry season. (3) Adjusted R 2 values in OLS models using the manual variable excluding-selecting method averaged 14.3% higher than using stepwise multiple linear regressions. However, the corresponding GWR models had adjusted R 2 ~59.2% higher than the optimal OLS models, confirming that GWR models demonstrated better prediction accuracy. Based on our findings, water resource protection policies should consider site-specific land-use conditions within each watershed to optimize mitigation strategies for contrasting land-use characteristics and seasonal variations. Copyright © 2016 Elsevier B.V. All rights reserved.

Thermal Band Analysis of Agricultural Land Use and its Effects on Bioclimatic Comfort: The Case of Pasinler

NASA Astrophysics Data System (ADS)

Avdan, Uǧur; Demircioglu Yildiz, Nalan; Dagliyar, Ayse; Yigit Avdan, Zehra; Yilmaz, Sevgi

2014-05-01

Resolving the problems that arise due to the land use are not suitable for the purpose in the rural and urban areas most suitable for land use of parameters to be determined. Unintended and unplanned developments in the use of agricultural land in our country caused increases the losses by soil erosion. In this study, Thermal Band analysis is made in Pasinler city center with the aim of identifying bioclimatic comfort values of the different agricultural area. Satellite images can be applied for assessing the thermal urban environment as well as for defining heat islands in agricultural areas. In this context, temperature map is tried to be produced with land surface temperature (LST) analysis made on Landsat TM5 satellite image. The Landsat 5 images was obtained from USGS for the study area. Using Landsat bands of the study area was mapped by supervised classification with the maximum likelihood classification algorithm of ERDAS imagine 2011 software. Normalized Difference Vegetation Index (NDVI) image was produced by using Landsat images. The digital number of the Landsat thermal infrared band (10.40 - 12.50 µm) is converted to the spectral radiance. The surface emissivity was calculated by using NDVI. The spatial pattern of land surface temperature in the study area is taken to characterize their local effects on agricultural land. Areas having bioclimatic comfort and ecologically urbanized, are interpreted with different graphical presentation technics. The obtained results are important because they create data bases for sustainable urban planning and provide a direction for planners and governors. As a result of rapid changes in land use, rural ecosystems and quality of life are deteriorated and decreased. In the presence of increased building density, for the comfortable living of people natural and cultural resources should be analyzed in detail. For that reason, optimal land use planning should be made in rural area.

Landscape characteristics affecting streams in urbanizing regions of the Delaware River Basin (New Jersey, New York, and Pennsylvania, U.S.)

USGS Publications Warehouse

Riva-Murray, K.; Riemann, R.; Murdoch, P.; Fischer, J.M.; Brightbill, R.

2010-01-01

Widespread and increasing urbanization has resulted in the need to assess, monitor, and understand its effects on stream water quality. Identifying relations between stream ecological condition and urban intensity indicators such as impervious surface provides important, but insufficient information to effectively address planning and management needs in such areas. In this study we investigate those specific landscape metrics which are functionally linked to indicators of stream ecological condition, and in particular, identify those characteristics that exacerbate or mitigate changes in ecological condition over and above impervious surface. The approach used addresses challenges associated with redundancy of landscape metrics, and links landscape pattern and composition to an indicator of stream ecological condition across a broad area of the eastern United States. Macroinvertebrate samples were collected during 2000-2001 from forty-two sites in the Delaware River Basin, and landscape data of high spatial and thematic resolution were obtained from photointerpretation of 1999 imagery. An ordination-derived 'biotic score' was positively correlated with assemblage tolerance, and with urban-related chemical characteristics such as chloride concentration and an index of potential pesticide toxicity. Impervious surface explained 56% of the variation in biotic score, but the variation explained increased to as high as 83% with the incorporation of a second land use, cover, or configuration metric at catchment or riparian scales. These include land use class-specific cover metrics such as percent of urban land with tree cover, forest fragmentation metrics such as aggregation index, riparian metrics such as percent tree cover, and metrics related to urban aggregation. Study results indicate that these metrics will be important to monitor in urbanizing areas in addition to impervious surface. ?? 2010 US Government.

A global map of urban extent from nightlights

DOE PAGES

Zhou, Yuyu; Smith, Steven J.; Zhao, Kaiguang; ...

2015-05-13

Urbanization, one of the major human induced land-cover and land-use changes, has a profound impact on the Earth system including biodiversity, the cycling of water and carbon and exchange of energy and water between Earth’s surface and atmosphere, all affecting weather and climate. Accurate information on urban areas and their spatial distribution at the regional and global scales is important for scientific understanding of their contribution to the changing Earth system, and for practical management and policy decisions. We developed a method to map the urban extent from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime stable-light data atmore » the global level and derived a new global map of 1-km urban extent for year 2000. Based on this map, we found that globally, urban land area is about 0.5% of total land area but ranges widely at regional level from 0.1% in Oceania to 2.3% in Europe. At the country level, urban land area varies from lower than 0.01% to higher than 10%, but is lower than 1% for most (70%) countries. Urbanization follows land mass distribution, as anticipated, with the highest concentration found between 30°N to 45°N latitude and the largest longitudinal peak around 80°W. Based on a sensitivity analysis and comparison with other global urban area products, we found that our global product of urban area provides a reliable estimate of global urban areas and offer the potential of capturing more accurately their spatial and temporal dynamics.« less

Mapping Urban Ecosystem Services Using High Resolution Aerial Photography

NASA Astrophysics Data System (ADS)

Pilant, A. N.; Neale, A.; Wilhelm, D.

2010-12-01

Ecosystem services (ES) are the many life-sustaining benefits we receive from nature: e.g., clean air and water, food and fiber, cultural-aesthetic-recreational benefits, pollination and flood control. The ES concept is emerging as a means of integrating complex environmental and economic information to support informed environmental decision making. The US EPA is developing a web-based National Atlas of Ecosystem Services, with a component for urban ecosystems. Currently, the only wall-to-wall, national scale land cover data suitable for this analysis is the National Land Cover Data (NLCD) at 30 m spatial resolution with 5 and 10 year updates. However, aerial photography is acquired at higher spatial resolution (0.5-3 m) and more frequently (1-5 years, typically) for most urban areas. Land cover was mapped in Raleigh, NC using freely available USDA National Agricultural Imagery Program (NAIP) with 1 m ground sample distance to test the suitability of aerial photography for urban ES analysis. Automated feature extraction techniques were used to extract five land cover classes, and an accuracy assessment was performed using standard techniques. Results will be presented that demonstrate applications to mapping ES in urban environments: greenways, corridors, fragmentation, habitat, impervious surfaces, dark and light pavement (urban heat island). Automated feature extraction results mapped over NAIP color aerial photograph. At this scale, we can look at land cover and related ecosystem services at the 2-10 m scale. Small features such as individual trees and sidewalks are visible and mappable. Classified aerial photo of Downtown Raleigh NC Red: impervious surface Dark Green: trees Light Green: grass Tan: soil

Monitoring Spatiotemporal Changes of Heat Island in Babol City due to Land Use Changes

NASA Astrophysics Data System (ADS)

Alavi Panah, S. K.; Kiavarz Mogaddam, M.; Karimi Firozjaei, M.

2017-09-01

Urban heat island is one of the most vital environmental risks in urban areas. The advent of remote sensing technology provides better visibility due to the integrated view, low-cost, fast and effective way to study and monitor environmental and humanistic changes. The aim of this study is a spatiotemporal evaluation of land use changes and the heat island in the time period of 1985-2015 for the studied area in the city of Babol. For this purpose, multi-temporal Landsat images were used in this study. For calculating the land surface temperature (LST), single-channel and maximum likelihood algorithms were used, to classify Images. Therefore, land use changes and LST were examined, and thereby the relationship between land-use changes was analyzed with the normalized LST. By using the average and standard deviation of normalized thermal images, the area was divided into five temperature categories, inter alia, very low, low, medium, high and very high and then, the heat island changes in the studied time period were investigated. The results indicate that land use changes for built-up lands increased by 92%, and a noticeable decrease was observed for agricultural lands. The Built-up land changes trend has direct relation with the trend of normalized surface temperature changes. Low and very low-temperature categories which follow a decreasing trend, are related to lands far away from the city. Also, high and very high-temperature categories whose areas increase annually, are adjacent to the city center and exit ways of the town. The results emphasize on the importance of attention of urban planners and managers to the urban heat island as an environmental risk.

Spatial-temporal change of land surface temperature across 285 cities in China: An urban-rural contrast perspective.

PubMed

Peng, Jian; Ma, Jing; Liu, Qianyuan; Liu, Yanxu; Hu, Yi'na; Li, Yingru; Yue, Yuemin

2018-09-01

As an important theme in global climate change and urban sustainable development, the changes of land surface temperature (LST) and surface urban heat island (SUHI) have been more and more focused by urban ecologists. This study used land-use data to identify the urban-rural areas in 285 cities in China and comparatively analyzed LST in urban-rural areas with the perspective of spatial-temporal dynamics heterogeneity. The results showed that, 98.9% of the cities exhibited SUHI effect in summer nighttime and the effect was stronger in northern cities than that in southern cities. In 2010, the mean SUHI intensity was the largest in summer daytime, with 4.6% of the cities having extreme SUHI of over 4°C. From 2001 to 2010, the nighttime LST of most cities increased more quickly in urban areas compared with rural areas, with an increasing tendency of the urban-rural LST difference. The difference in the urban- rural LST change rate was concentrated in the range of 0-0.1°C/year for 68.0% of cities in winter and 70.8% of cities in summer. For the higher LST increasing in urban areas compared with rural areas, there were more cities in summer than winter, indicating that the summer nighttime was the key temporal period for SUHI management. Based on the change slope of urban-rural LST, cities were clustered into four types and the vital and major zones for urban thermal environment management were identified in China. The vital zone included cities in Hunan, Hubei and other central rising provinces as well as the Beibu Gulf of Guangxi Province. The major zone included most of the cities in Central Plain Urban Agglomeration, Yangtze River Delta and Pearl River Delta. These results can provide scientific basis for SUHI adaptation in China. Copyright © 2018 Elsevier B.V. All rights reserved.

Evapotranspiration and surface energy balance across an agricultural-urban landscape gradient in Southern California, USA.

NASA Astrophysics Data System (ADS)

Shiflett, S. A.; Anderson, R. G.; Jenerette, D.

2014-12-01

Urbanization substantially affects energy, surface and air temperature, and hydrology due to extensive modifications in land surface properties such as vegetation, albedo, thermal capacity and soil moisture. The magnitude and direction of these alterations depends heavily on the type of urbanization that occurs. We investigated energy balance variation in a local network of agricultural and urban ecosystems using the eddy covariance method to better understand how vegetation fraction and degree of urbanization affects energy exchanges between the land surface and the atmosphere. We deployed eddy flux systems within a well-irrigated, agricultural citrus orchard, a moderately developed urban zone with a substantial amount of local vegetative cover, and an intensely developed urban zone with minimal vegetative cover and increased impervious surfaces relative to the other two sites. Latent energy (LE) fluxes in the agricultural area ranged from 7.9 ± 1.4 W m-2 (nighttime) to 168.7 ± 6.2 W m-2 (daytime) compared to 10.2 ± 3.5 W m-2 and 40.6 ± 4.1 W m-2, respectively, for the moderately developed urban area. Sensible energy (H) fluxes ranged from -9.1 ± 1.0 W m-2 (nighttime) to 119 ± 7.0 W m-2 (daytime) in the agricultural area compared to 9.6 ± 2.6 W m-2 and 134 ± 6.0 W m-2, respectively, for the moderately developed urban zone. Daytime LE is reduced with increasing urbanization; however, daily cycles of LE are less recognizable in urban areas compared to distinct daily cycles obtained above a mature citrus crop. In contrast, both daytime and nighttime H increases with increasing degree of urbanization. Reduction in vegetation and increases in impervious surfaces along an urbanization gradient leads to alterations in energy balance, which are associated with microclimate and water use changes.

Use of radar in urban studies

NASA Technical Reports Server (NTRS)

Bryan, M. L.

1976-01-01

The use of side-looking airborne radar for urban studies is reviewed with attention given to the work of Moore (1969) and Lewis (1968) which may be summarized as follows: (1) linear elements of the transportation net were easily defined, (2) gross patterns of industry, residential and open space land were identified, but it was not possible to map the land use boundaries in great detail, (3) commercial land areas were often difficult to identify, and (4) multiple polarized imagery was helpful in correctly interpreting the total scene. It is found that the sensitivity of radar to surface roughness and the availability of multiple wavelength data allow the discrimination of variations in the surface roughness of intra-urban areas. An L-band imaging radar (25 cm; 1215-1225 GHz) of 25 m resolution will be operating from satellite altitudes in 1978 and will increase the availability of radar data.

Tampa Bay Integrated Science Pilot Study: Baseline mapping, land surface dynamics and predictive modeling, and hazards vulnerability studies

USGS Publications Warehouse

Crane, Michael; Yates, Kimberly; Clark, Robert; Gesch, Dean; Hess, Kurt; Koehmstedt, John; Milbert, Dennis; Parker, Bruce; Sechrist, Dan; Tilley, Janet; Wilson, Robert

2001-01-01

Tampa Bay and its environs have experienced phenomenal urban growth and significant changes in land cover and land-use practices over the past 50 years. This trend is expected to continue, with the impact of human activity broadening geographically and intensifying throughout the region.One of the immediate impacts of urban growth is the creation of additional impervious surfaces, which in turn, generate increased urban runoff that contributes to higher levels of nutrient loading in water bodies throughout the area.To better understand these and other anthropogenic affects on the ecology of the natural environment of the region, this component of the Tampa Bay Pilot Study took a broad basin-wide view. This regional view was intended to provide geographic and temporal context for the smaller intensely studied sample field site locations within the estuarine environment.

A numerical forecast model for road meteorology

NASA Astrophysics Data System (ADS)

Meng, Chunlei

2017-05-01

A fine-scale numerical model for road surface parameters prediction (BJ-ROME) is developed based on the Common Land Model. The model is validated using in situ observation data measured by the ROSA road weather stations of Vaisala Company, Finland. BJ-ROME not only takes into account road surface factors, such as imperviousness, relatively low albedo, high heat capacity, and high heat conductivity, but also considers the influence of urban anthropogenic heat, impervious surface evaporation, and urban land-use/land-cover changes. The forecast time span and the update interval of BJ-ROME in vocational operation are 24 and 3 h, respectively. The validation results indicate that BJ-ROME can successfully simulate the diurnal variation of road surface temperature both under clear-sky and rainfall conditions. BJ-ROME can simulate road water and snow depth well if the artificial removing was considered. Road surface energy balance in rainy days is quite different from that in clear-sky conditions. Road evaporation could not be neglected in road surface water cycle research. The results of sensitivity analysis show solar radiation correction coefficient, asphalt depth, and asphalt heat conductivity are important parameters in road interface temperatures simulation. The prediction results could be used as a reference of maintenance decision support system to mitigate the traffic jam and urban water logging especially in large cities.

Numerical simulation of the effects of urban land-use changes on the local climate of multiple desert cities

NASA Astrophysics Data System (ADS)

Kamal, S. M.; Huang, H. P.; Myint, S. W.

2016-12-01

This study quantifies the effect of urbanization on local climate by numerical simulations for multiple desert cities with a wide range of urban size, baseline climatology, and composition of land cover. The numerical experiments use the Weather Research and Forecasting (WRF) model with multiple layers of nesting centered at a desert city. To extract the influence of land-use changes, twin runs are performed with each pair driven by the same time-varying lateral boundary conditions from reanalysis but different land surface conditions from Landsat observations for 1985 and 2010. The differences in the meteorological fields between the two runs are interpreted as the effects of land-use changes due to urbanization from 1985-2010. Using this strategy, simulations are carried out for five desert cities: (1) Las Vegas, United States, (2) Hotan, China, (3) Kharga, Egypt, (4) Beer Sheva, Israel, and (5) Jodhpur, India. The results of the simulations reveal a common pattern of the climatic effect of desert urbanization with nighttime warming but daytime cooling over areas where urbanization occurred. This effect is mainly confined to the urban area and is not sensitive to the size of the city or the detail of land cover in the surrounding non-urban areas. The pattern is similar in winter and summer. Exceptions to this pattern are found in a few cases in which the noisiness of local circulation, specifically monsoon and land-sea breeze, overwhelms the climatic signal induced by land-use changes. Although the local climatic responses to urbanization are qualitatively similar for the five desert cities, quantitative differences exist in the magnitudes of nighttime warming and daytime cooling. The possible reasons for those secondary differences are discussed.

Accuracy assessment of NLCD 2006 land cover and impervious surface

USGS Publications Warehouse

Wickham, James D.; Stehman, Stephen V.; Gass, Leila; Dewitz, Jon; Fry, Joyce A.; Wade, Timothy G.

2013-01-01

Release of NLCD 2006 provides the first wall-to-wall land-cover change database for the conterminous United States from Landsat Thematic Mapper (TM) data. Accuracy assessment of NLCD 2006 focused on four primary products: 2001 land cover, 2006 land cover, land-cover change between 2001 and 2006, and impervious surface change between 2001 and 2006. The accuracy assessment was conducted by selecting a stratified random sample of pixels with the reference classification interpreted from multi-temporal high resolution digital imagery. The NLCD Level II (16 classes) overall accuracies for the 2001 and 2006 land cover were 79% and 78%, respectively, with Level II user's accuracies exceeding 80% for water, high density urban, all upland forest classes, shrubland, and cropland for both dates. Level I (8 classes) accuracies were 85% for NLCD 2001 and 84% for NLCD 2006. The high overall and user's accuracies for the individual dates translated into high user's accuracies for the 2001–2006 change reporting themes water gain and loss, forest loss, urban gain, and the no-change reporting themes for water, urban, forest, and agriculture. The main factor limiting higher accuracies for the change reporting themes appeared to be difficulty in distinguishing the context of grass. We discuss the need for more research on land-cover change accuracy assessment.

The urban moisture climate

Treesearch

Douglas L. Sisterson

1977-01-01

Data collected on 26 July 1974 as a part of project METROMEX in St. Louis show the three-dimensional structure of the urban moisture field. Mesoscale dry regions at the urban surface, corresponding to large residential and light industrial land-use characterization, were responsible for a reduction in specific humidity in the urban mixing layer. Anthropogenic sources...

Modeling Surface Climate in US Cities Using Simple Biosphere Model Sib2

NASA Technical Reports Server (NTRS)

Zhang, Ping; Bounoua, Lahouari; Thome, Kurtis; Wolfe, Robert; Imhoff, Marc

2015-01-01

We combine Landsat- and the Moderate Resolution Imaging Spectroradiometer (MODIS)-based products in the Simple Biosphere model (SiB2) to assess the effects of urbanized land on the continental US (CONUS) surface climate. Using National Land Cover Database (NLCD) Impervious Surface Area (ISA), we define more than 300 urban settlements and their surrounding suburban and rural areas over the CONUS. The SiB2 modeled Gross Primary Production (GPP) over the CONUS of 7.10 PgC (1 PgC= 10(exp 15) grams of Carbon) is comparable to the MODIS improved GPP of 6.29 PgC. At state level, SiB2 GPP is highly correlated with MODIS GPP with a correlation coefficient of 0.94. An increasing horizontal GPP gradient is shown from the urban out to the rural area, with, on average, rural areas fixing 30% more GPP than urbans. Cities built in forested biomes have stronger UHI magnitude than those built in short vegetation with low biomass. Mediterranean climate cities have a stronger UHI in wet season than dry season. Our results also show that for urban areas built within forests, 39% of the precipitation is discharged as surface runoff during summer versus 23% in rural areas.

Urban growth in American cities : glimpses of U.S. urbanization

USGS Publications Warehouse

Auch, Roger; Taylor, Janis; Acevedo, William

2004-01-01

The Earth's surface is changing rapidly. Changes are local, regional, national, and even global in scope. Some changes have natural causes, such as earthquakes or drought. Other changes, such as urban expansion, agricultural intensification, resource extraction, and water resources development, are examples of human-induced change that have significant impact upon people, the economy, and resources. The consequences that result from these changes are often dramatic and widespread (Buchanan, Acevedo, and Zirbes, 2002)It is the role of the U.S. Geological Survey (USGS) to provide useful and relevant scientific information both to the agencies within the Department of the Interior and to the Nation in general. In an effort to comply with this task, USGS scientists are assessing the status of, and the trends in, the Nation's land surface. This assessment provides useful information for regional and national land use decisionmaking. This knowledge can be used to deal with issues of significance to the Nation, such as quality-of-life, ecology of urban environments, ecosystem health, ecological integrity, water quality and quantity concerns, resource availability, vulnerability to natural hazards, safeguards to human health, air and land quality, and accessibility to scientific information. Results of these assessments can also be analyzed to reveal rates and trends in land use change. Results from urban growth studies provide a firm foundation for continuing research that explores the consequences of human modification of the landscape.The USGS seeks to illustrate and explain the spatial history of urban growth and corresponding land use change. Scientists are studying urban environments from a regional perspective and a time scale of decades to measure the changes that have occurred in order to help understand the impact of anticipated changes in the future.Within this booklet are pairs of images of selected urbanized regions from across the Nation. These image pairs illustrate the transformation that these areas have undergone over two decades. Specifically, they depict changes in the extent of urban land. Each change pair is composed of one image from the 1970s and one image from the 1990s. Accompanying each image pair is a brief historical geography of factors that helped facilitate major changes that have occurred since the founding of the main city and the consequences and challenges of regional urban growth. The goal of this publication is to provide an illustration of urban change that is easily understood by a broad audience.The images used throughout this booklet were generated from land cover data developed by the USGS. The data sources include the Geographic Information Retrieval and Analysis System (GIRAS) for the 1970s images and the National Land Cover Dataset (NLCD) for the 1990s images. GIRAS digital maps are based on photointerpretations completed in the mid-1970s. The NLCD is a land cover dataset for the conterminous United States based on 1992 Landsat thematic mapper (TM) satellite imagery and supplemental data (fig. 1a and fig. 1b). The USGS distributes both of these land use and land cover digital datasets.The images were developed by using a geographic information system (GIS). The GIRAS and NLCD datasets were used to identify urban land within each region. In the final images all urban areas are shown in red. A shaded-relief map of each region was used to display the topographic context of the red polygon coverage. For all of these images, urban land is defined as areas transformed into a built-up environment for human use. It includes residential areas, commercial and industrial developments, transportation features, and institutions.

Cities as selective land predators? A lesson on urban growth, deregulated planning and sprawl containment.

PubMed

Colantoni, Andrea; Grigoriadis, Efstathios; Sateriano, Adele; Venanzoni, Giuseppe; Salvati, Luca

2016-03-01

The present study investigates changes in the use of land caused by the expansion of an informal city in the Mediterranean region (Athens, Greece) and it proposes a simplified methodology to assess selective land take at the scale of municipalities. The amount of land take over twenty years (1987-2007) for cropland, sparsely vegetated areas and natural land was compared with the surface area of the respective class at the beginning of the study period (1987). Indicators of selective land take by class were correlated with socioeconomic indicators at the scale of municipalities to verify the influence of the local context and the impact of urban planning on land take processes. Evidence indicates that urban expansion into fringe land consumes primarily cropland and sparse vegetation in the case of the Athens' metropolitan region. Cropland and sparse vegetation were consumed proportionally more than the respective availability in 16 municipalities out of 60. Agricultural land take was positively correlated with population density and growth rate, rate of participation to the job market and road density. Sparse vegetation land take was observed in municipalities with predominance of high density settlements. As a result of second-home expansion in coastal municipalities, natural land was converted to urban use in proportion to the availability in the landscape. Urban planning seems to have a limited impact on selective land take. Copyright © 2015 Elsevier B.V. All rights reserved.

Current and historical land use influence soil-based ecosystem services in an urban landscape.

PubMed

Ziter, Carly; Turner, Monica G

2018-04-01

Urban landscapes are increasingly recognized as providing important ecosystem services (ES) to their occupants. Yet, urban ES assessments often ignore the complex spatial heterogeneity and land-use history of cities. Soil-based services may be particularly susceptible to land-use legacy effects. We studied indicators of three soil-based ES, carbon storage, water quality regulation, and runoff regulation, in a historically agricultural urban landscape and asked (1) How do ES indicators vary with contemporary land cover and time since development? (2) Do ES indicators vary primarily among land-cover classes, within land-cover classes, or within sites? (3) What is the relative contribution of urban land-cover classes to potential citywide ES provision? We measured biophysical indicators (soil carbon [C], available phosphorus [P], and saturated hydraulic conductivity [K s ]) in 100 sites across five land-cover classes, spanning an ~125-year gradient of time since development within each land-cover class. Potential for ES provision was substantial in urban green spaces, including developed land. Runoff regulation services (high K s ) were highest in forests; water quality regulation (low P) was highest in open spaces and grasslands; and open spaces and developed land (e.g., residential yards) had the highest C storage. In developed land covers, both C and P increased with time since development, indicating effects of historical land-use on contemporary ES and trade-offs between two important ES. Among-site differences accounted for a high proportion of variance in soil properties in forests, grasslands, and open space, while residential areas had high within-site variability, underscoring the leverage city residents have to improve urban ES provision. Developed land covers contributed most ES supply at the citywide scale, even after accounting for potential impacts of impervious surfaces. Considering the full mosaic of urban green space and its history is needed to estimate the kinds and magnitude of ES provided in cities, and to augment regional ES assessments that often ignore or underestimate urban ES supply. © 2018 by the Ecological Society of America.

Multi-sensor analysis of urban ecosystems

USGS Publications Warehouse

Gallo, Kevin P.; Ji, Lei

2004-01-01

This study examines the synthesis of multiple space-based sensors to characterize the urban environment Single scene data (e.g., ASTER visible and near-IR surface reflectance, and land surface temperature data), multi-temporal data (e.g., one year of 16-day MODIS and AVHRR vegetation index data), and DMSP-OLS nighttime light data acquired in the early 1990s and 2000 were evaluated for urban ecosystem analysis. The advantages of a multi-sensor approach for the analysis of urban ecosystem processes are discussed.

Impacts of Urbanization in the Coastal Tropical City of San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Comarazamy, Daniel E.; Gonzalez, Jorge E.; Luvall, Jeffrey C.; Rickman, Douglas L.; Mulero, Pedro J.

2007-01-01

Urban sprawl in tropical locations is rapidly accelerating and it is more evident in islands where a large percentage of the population resides along the coasts. This paper focuses on the analysis of the impacts of land use and land cover for urbanization in the tropical coastal city of San Juan, in the Caribbean island of Puerto Rico. A mesoscale numerical model, the Regional Atmospheric Modeling System (RAMS), is used to study the impacts of land use for urbanization in the environment including specific characteristics of the urban heat island in the San Juan Metropolitan Area (SJMA), one of the most noticeable urban cores of the Caribbean. The research also makes use of the observations obtained during the airborne San Juan Atlas Mission. Surface and rawinsonde data from the mission are used to validate the atmospheric model yielding satisfactory results. Airborne high resolution remote sensing data are used to update the model's surface characteristics in order to obtain a more accurate and detailed configuration of the SJMA and perform a climate impact analysis based on land cover/land use (LCLU) changes. The impact analysis showed that the presence of the urban landscape of San Juan has an impact reflected in higher air temperatures over the area occupied by the city, with positive values of up to 2.5 C, for the simulations that have specified urban LCLU indexes in the model's bottom boundary. One interesting result of the impact analysis was the finding of a precipitation disturbance shown as a difference in total accumulated rainfall between the present urban landscape and with a potential natural vegetation, apparently induced by the presence of the urban area. Results indicate that the urban enhanced cloud formation and precipitation development occur mainly downwind of the city, including the accumulated precipitation. This spatial pattern can be explained by the presence of a larger urbanized area in the southwest sector of the city, and of the approaching northeasterly trade winds. No significant impacts were found in the sea breeze patterns of the city.

Linking the Local Climate Zones and Land Surface Temperature to Investigate the Surface Urban Heat Island, a Case Study of San Antonio, Texas, U.S.

NASA Astrophysics Data System (ADS)

Zhao, Chunhong

2018-04-01

The Local Climate Zones (LCZs) concept was initiated in 2012 to improve the documentation of Urban Heat Island (UHI) observations. Despite the indispensable role and initial aim of LCZs concept in metadata reporting for atmospheric UHI research, its role in surface UHI investigation also needs to be emphasized. This study incorporated LCZs concept to study surface UHI effect for San Antonio, Texas. LCZ map was developed by a GIS-based LCZs classification scheme with the aid of airborne Lidar dataset and other freely available GIS data. Then, the summer LST was calculated based Landsat imagery, which was used to analyse the relations between LST and LCZs and the statistical significance of the differences of LST among the typical LCZs, in order to test if LCZs are able to efficiently facilitate SUHI investigation. The linkage of LCZs and land surface temperature (LST) indicated that the LCZs mapping can be used to compare and investigate the SUHI. Most of the pairs of LCZs illustrated significant differences in average LSTs with considerable significance. The intra-urban temperature comparison among different urban classes contributes to investigate the influence of heterogeneous urban morphology on local climate formation.

Integrating seasonal optical and thermal infrared spectra to characterize urban impervious surfaces with extreme spectral complexity: a Shanghai case study

NASA Astrophysics Data System (ADS)

Wang, Wei; Yao, Xinfeng; Ji, Minhe

2016-01-01

Despite recent rapid advancement in remote sensing technology, accurate mapping of the urban landscape in China still faces a great challenge due to unusually high spectral complexity in many big cities. Much of this complication comes from severe spectral confusion of impervious surfaces with polluted water bodies and bright bare soils. This paper proposes a two-step land cover decomposition method, which combines optical and thermal spectra from different seasons to cope with the issue of urban spectral complexity. First, a linear spectral mixture analysis was employed to generate fraction images for three preliminary endmembers (high albedo, low albedo, and vegetation). Seasonal change analysis on land surface temperature induced from thermal infrared spectra and coarse component fractions obtained from the first step was then used to reduce the confusion between impervious surfaces and nonimpervious materials. This method was tested with two-date Landsat multispectral data in Shanghai, one of China's megacities. The results showed that the method was capable of consistently estimating impervious surfaces in highly complex urban environments with an accuracy of R2 greater than 0.70 and both root mean square error and mean average error less than 0.20 for all test sites. This strategy seemed very promising for landscape mapping of complex urban areas.

Climatology of Urban-regional Systems

NASA Technical Reports Server (NTRS)

Pease, R. W.

1971-01-01

Urbanized areas have come to be significant if not dominant components of many regional land surfaces. They represent perhaps the most dramatic recent change man has made in his environment - a change that may well burgeon in the foreseeable future as greater percentages of world populations crowd into metropolitan areas. The climate of urban-regional systems is involved because temperature, air, and pollutants added to the air are significant aspects of this change. During the past two years, substantial progress has been made in the application of remote sensing techniques to the study of urban climatology by programs jointly sponsored by NASA and the United States Geological Survey. The initial effort has endeavored with considerable success to map terrestrial radiation emission or the general thermal state of the land surface with the aid of imaging radiometers (mechanical-optical scanners).

[A landscape ecological approach for urban non-point source pollution control].

PubMed

Guo, Qinghai; Ma, Keming; Zhao, Jingzhu; Yang, Liu; Yin, Chengqing

2005-05-01

Urban non-point source pollution is a new problem appeared with the speeding development of urbanization. The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution, and more difficult to control. Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution, mainly adopting local repairing practices to control the pollutants in surface runoff. Because of the close relationship between urban land use patterns and non-point source pollution, it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution, which needs, firstly, analyzing and evaluating the influence of landscape structure on water-bodies, pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields, and secondly, adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern, and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.

Detecting Changes of Thermal Environment over the Bohai Coastal Region by Spectral Change Vector Analysis

NASA Astrophysics Data System (ADS)

Hu, Y.; Jia, G.

2009-12-01

Change vector analysis (CVA) is an effective approach for detecting and characterizing land-cover change by comparing pairs of multi-spectral and multi-temporal datasets over certain area derived from various satellite platforms. NDVI is considered as an effective detector for biophysical changes due to its sensitivity to red and near infrared signals, while land surface temperature (LST) is considered as a valuable indicator for changes of ground thermal conditions. Here we try to apply CVA over satellite derived LST datasets to detect changes of land surface thermal properties parallel to climate change and anthropogenic influence in a city cluster since 2001. In this study, monthly land surface temperature datasets from 2001-2008 derived from MODIS collection 5 were used to examine change pattern of thermal environment over the Bohai coastal region by using spectral change vector analysis. The results from principle component analysis (PCA) for LST show that the PC 1-3 contain over 80% information on monthly variations and these PCA components represent the main processes of land thermal environment change over the study area. Time series of CVA magnitude combined with land cover information show that greatest change occurred in urban and heavily populated area, featured with expansion of urban heat island, while moderate change appeared in grassland area in the north. However few changes were observed over large plain area and forest area. Strong signals also are related to economy level and especially the events of surface cover change, such as emergence of railway and port. Two main processes were also noticed about the changes of thermal environment. First, weak signal was detected in mostly natural area influenced by interannual climate change in temperate broadleaf forest area. Second, land surface temperature changes were controlled by human activities as 1) moderate change of LST happened in grassland influenced by grazing and 2) urban heat island was intensifier in major cities, such as Beijing and Tianjin. Further, the continual drier climate combined with human actions over past fifties years have intensified land thermal pattern change and the continuation will be an important aspects to understand land surface processes and local climate change. Land surface temperature trends from 2000-2008 over the Bohai coastal region

The use of LiDAR-derived high-resolution DSM and intensity data to support modelling of urban flooding

NASA Astrophysics Data System (ADS)

Aktaruzzaman, Md.; Schmitt, Theo G.

2011-11-01

This paper addresses the issue of a detailed representation of an urban catchment in terms of hydraulic and hydrologic attributes. Modelling of urban flooding requires a detailed knowledge of urban surface characteristics. The advancement in spatial data acquisition technology such as airborne LiDAR (Light Detection and Ranging) has greatly facilitated the collection of high-resolution topographic information. While the use of the LiDAR-derived Digital Surface Model (DSM) has gained popularity over the last few years as input data for a flood simulation model, the use of LiDAR intensity data has remained largely unexplored in this regard. LiDAR intensity data are acquired along with elevation data during the data collection mission by an aircraft. The practice of using of just aerial images with RGB (Red, Green and Blue) wavebands is often incapable of identifying types of surface under the shadow. On the other hand, LiDAR intensity data can provide surface information independent of sunlight conditions. The focus of this study is the use of intensity data in combination with aerial images to accurately map pervious and impervious urban areas. This study presents an Object-Based Image Analysis (OBIA) framework for detecting urban land cover types, mainly pervious and impervious surfaces in order to improve the rainfall-runoff modelling. Finally, this study shows the application of highresolution DSM and land cover maps to flood simulation software in order to visualize the depth and extent of urban flooding phenomena.

Impacts of urban and industrial development on Arctic land surface temperature in Lower Yenisei River Region.

NASA Astrophysics Data System (ADS)

Li, Z.; Shiklomanov, N. I.

2015-12-01

Urbanization and industrial development have significant impacts on arctic climate that in turn controls settlement patterns and socio-economic processes. In this study we have analyzed the anthropogenic influences on regional land surface temperature of Lower Yenisei River Region of the Russia Arctic. The study area covers two consecutive Landsat scenes and includes three major cities: Norilsk, Igarka and Dudingka. Norilsk industrial region is the largest producer of nickel and palladium in the world, and Igarka and Dudingka are important ports for shipping. We constructed a spatio-temporal interpolated temperature model by including 1km MODIS LST, field-measured climate, Modern Era Retrospective-analysis for Research and Applications (MERRA), DEM, Landsat NDVI and Landsat Land Cover. Those fore-mentioned spatial data have various resolution and coverage in both time and space. We analyzed their relationships and created a monthly spatio-temporal interpolated surface temperature model at 1km resolution from 1980 to 2010. The temperature model then was used to examine the characteristic seasonal LST signatures, related to several representative assemblages of Arctic urban and industrial infrastructure in order to quantify anthropogenic influence on regional surface temperature.

Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams

PubMed Central

Feist, Blake E.; Buhle, Eric R.; Arnold, Paul; Davis, Jay W.; Scholz, Nathaniel L.

2011-01-01

In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to spawn in urban basins of the Puget Sound region have been prematurely dying at high rates (up to 90% of the total runs) for more than a decade. The current weight of evidence indicates that coho deaths are caused by toxic chemical contaminants in land-based runoff to urban streams during the fall spawning season. Non-point source pollution in urban landscapes typically originates from discrete urban and residential land use activities. In the present study we conducted a series of spatial analyses to identify correlations between land use and land cover (roadways, impervious surfaces, forests, etc.) and the magnitude of coho mortality in six streams with different drainage basin characteristics. We found that spawner mortality was most closely and positively correlated with the relative proportion of local roads, impervious surfaces, and commercial property within a basin. These and other correlated variables were used to identify unmonitored basins in the greater Seattle metropolitan area where recurrent coho spawner die-offs may be likely. This predictive map indicates a substantial geographic area of vulnerability for the Puget Sound coho population segment, a species of concern under the U.S. Endangered Species Act. Our spatial risk representation has numerous applications for urban growth management, coho conservation, and basin restoration (e.g., avoiding the unintentional creation of ecological traps). Moreover, the approach and tools are transferable to areas supporting coho throughout western North America. PMID:21858112

Development of a modular streamflow model to quantify runoff contributions from different land uses in tropical urban environments using Genetic Programming

NASA Astrophysics Data System (ADS)

Meshgi, Ali; Schmitter, Petra; Chui, Ting Fong May; Babovic, Vladan

2015-06-01

The decrease of pervious areas during urbanization has severely altered the hydrological cycle, diminishing infiltration and therefore sub-surface flows during rainfall events, and further increasing peak discharges in urban drainage infrastructure. Designing appropriate waster sensitive infrastructure that reduces peak discharges requires a better understanding of land use specific contributions towards surface and sub-surface processes. However, to date, such understanding in tropical urban environments is still limited. On the other hand, the rainfall-runoff process in tropical urban systems experiences a high degree of non-linearity and heterogeneity. Therefore, this study used Genetic Programming to establish a physically interpretable modular model consisting of two sub-models: (i) a baseflow module and (ii) a quick flow module to simulate the two hydrograph flow components. The relationship between the input variables in the model (i.e. meteorological data and catchment initial conditions) and its overall structure can be explained in terms of catchment hydrological processes. Therefore, the model is a partial greying of what is often a black-box approach in catchment modelling. The model was further generalized to the sub-catchments of the main catchment, extending the potential for more widespread applications. Subsequently, this study used the modular model to predict both flow components of events as well as time series, and applied optimization techniques to estimate the contributions of various land uses (i.e. impervious, steep grassland, grassland on mild slope, mixed grasses and trees and relatively natural vegetation) towards baseflow and quickflow in tropical urban systems. The sub-catchment containing the highest portion of impervious surfaces (40% of the area) contributed the least towards the baseflow (6.3%) while the sub-catchment covered with 87% of relatively natural vegetation contributed the most (34.9%). The results from the quickflow module revealed average runoff coefficients between 0.12 and 0.80 for the various land uses and decreased from impervious (0.80), grass on steep slopes (0.56), grass on mild slopes (0.48), mixed grasses and trees (0.42) to relatively natural vegetation (0.12). The established modular model, reflecting the driving hydrological processes, enables the quantification of land use specific contributions towards the baseflow and quickflow components. This quantification facilitates the integration of water sensitive urban infrastructure for the sustainable development of water in tropical megacities.

Downscaling Satellite Land Surface Temperatures in Urban Regions for Surface Energy Balance Study and Heat Index Development

NASA Astrophysics Data System (ADS)

Norouzi, H.; Bah, A.; Prakash, S.; Nouri, N.; Blake, R.

2017-12-01

A great percentage of the world's population reside in urban areas that are exposed to the threats of global and regional climate changes and associated extreme weather events. Among them, urban heat islands have significant health and economic impacts due to higher thermal gradients of impermeable surfaces in urban regions compared to their surrounding rural areas. Therefore, accurate characterization of the surface energy balance in urban regions are required to predict these extreme events. High spatial resolution Land surface temperature (LST) in the scale of street level in the cities can provide wealth of information to study surface energy balance and eventually providing a reliable heat index. In this study, we estimate high-resolution LST maps using combination of LandSat 8 and infrared based satellite products such as Moderate Resolution Imaging Spectroradiometer (MODIS) and newly launched Geostationary Operational Environmental Satellite-R Series (GOES-R). Landsat 8 provides higher spatial resolution (30 m) estimates of skin temperature every 16 days. However, MODIS and GOES-R have lower spatial resolution (1km and 4km respectively) with much higher temporal resolution. Several statistical downscaling methods were investigated to provide high spatiotemporal LST maps in urban regions. The results reveal that statistical methods such as Principal Component Analysis (PCA) can provide reliable estimations of LST downscaling with 2K accuracy. Other methods also were tried including aggregating (up-scaling) the high-resolution data to a coarse one to examine the limitations and to build the model. Additionally, we deployed flux towers over distinct materials such as concrete, asphalt, and rooftops in New York City to monitor the sensible and latent heat fluxes through eddy covariance method. To account for the incoming and outgoing radiation, a 4-component radiometer is used that can observe both incoming and outgoing longwave and shortwave radiation. This enables us to accurately build the relationship between LST, air temperature, and the heat index in the future.

Urban Impact at the Urban-Agricultural Interface in Madison, WI: an Ecosystem Modeling Approach

NASA Astrophysics Data System (ADS)

Logan, K. E.; Kucharik, C. J.; Schneider, A.

2009-12-01

Global population and the proportion of people living in urban areas both continue to grow while average urban density is decreasing worldwide. Because urban areas are often located in the most agriculturally productive lands, expansion of the built environment can cause sharp reductions in land available for cultivation. Conversion of land to urban use also significantly alters climate variables. Urban materials differ from natural land covers in terms of albedo, thermal properties, and permeability, altering energy and water cycles. Anthropogenic heat emissions also alter the energy balance in and around a city. Preliminary analysis of urban impacts around Madison, WI, a small city located in a thriving agricultural region, was performed using the National Land Cover Database (NLCD), MODIS albedo products, ground-based observations, and a simulation of urban expansion, within a geographic information system (GIS). Population of the county is expected to increase by 58% while urban density is projected to decrease by 49% between 1992 and 2030, reflecting projected worldwide patterns. Carbon stored in the top 25cm of soil was found to be over 2.5 times greater in remnant prairies than in croplands and was calculated to be even less in urban areas; projected urban development may thus lead to large losses in carbon storage. Albedo measurements also show a significant decrease with urban development. Projected urban expansion between 2001 and 2030 is expected to convert enough agricultural lands to urban areas to result in a loss of 247,000 tons of crop yield in Dane County alone, based on current yields. For a more complete analysis of these impacts, urban parameters are incorporated into a terrestrial ecosystem model known as Agro-IBIS. This approach allows for detailed comparison of energy balance and biogeochemical cycles between local crop systems, lawns, and impervious city surfaces. Changes in these important cycles, in soil carbon storage, and in crop productivity/yield for 1992 - 2001 and projected 2030 development around Madison, WI will be shown.

Trend Assessment of Spatio-Temporal Change of Tehran Heat Island Using Satellite Images

NASA Astrophysics Data System (ADS)

Saradjian, M. R.; Sherafati, Sh.

2015-12-01

Numerous investigations on Urban Heat Island (UHI) show that land cover change is the main factor of increasing Land Surface Temperature (LST) in urban areas, especially conversion of vegetation and bare soil to concrete, asphalt and other man-made structures. On the other hand, other human activities like those which cause to burning fossil fuels, that increase the amount of carbon dioxide, may raise temperature in global scale in comparison with small scales (urban areas). In this study, multiple satellite images with different spatial and temporal resolutions have been used to determine Land Surface Temperature (LST) variability in Tehran metropolitan area. High temporal resolution of AVHRR images have been used as the main data source when investigating temperature variability in the urban area. The analysis shows that UHI appears more significant at afternoon and night hours. But the urban class temperature is almost equal to its surrounding vegetation and bare soil classes at around noon. It also reveals that there is no specific difference in UHI intense during the days throughout the year. However, it can be concluded that in the process of city expansion in years, UHI has been grown both spatially and in magnitude. In order to locate land-cover types and relate them to LST, Thematic Mapper (TM) images have been exploited. The influence of elevation on the LST has also been studied, using digital elevation model derived from SRTM database.

On the urban land-surface impact on climate over Central Europe

NASA Astrophysics Data System (ADS)

Huszar, Peter; Halenka, Tomas; Belda, Michal; Zemankova, Katerina; Zak, Michal

2014-05-01

For the purpose of qualifying and quantifying the impact of cities and in general the urban surfaces on climate over central Europe, the surface parameterization in regional climate model RegCM4 has been extended with the Single Layer Urban Canopy Model (SLUCM) for urban and suburban land surface. This can be used both in dynamic scale within BATS scheme and in a more detailed SUBBATS scale to treat the surface processes on a higher resolution subgrid. A set of experiments was performed over the period of 2005-2009 over central Europe, either without considering urban surfaces and with the SLUCM treatment. Results show a statistically significant impact of urbanized surfaces on temperature (up to 1.5 K increase in summer), on the boundary layer height (ZPBL, increases up to 50 m). Urbanization further influences surface wind with a winter decrease up to -0,6 m s-1 and both increases and decreases in summer depending the location with respect to cities and daytime (changes up to 0.3 ms-1). Urban surfaces significantly reduce evaporation and thus the humidity over the surface. This impacts in our simulations the summer precipitation rate showing decrease over cities up to - 2 mm day-1. We further showed, that significant temperature increases are not limited to the urban canopy layer but spawn the whole boundary layer. Above that, a small but statistically significant temperature decrease is modeled. The comparison with observational data showed significant improvement in modeling the monthly surface temperatures in summer and the models better describe the diurnal temperature variation reducing the afternoon and evening bias due to the UHI development, which was not captured by the model if one does not apply the urban parameterization. Sensitivity experiments were carried out as well to quantify the response of the meteorological conditions to changes in the parameters specific to the urban environment such as street width, building height, albedo of the roofs, anthropogenic heat release etc. and showed that the results are rather robust and the choice of the key SLUCM parameters impacts the results only slightly (mainly temperature, ZPBL and wind velocity). Further, the important conclusion is that statistically significant impacts are modeled not only over large urbanized areas (cities), but the influence of cities is evident over remote rural areas as well with minor or without any urban surfaces. We show that this is the result of the combined effect of the distant influence of surrounding cities and the influence of the minor local urban surface coverage.

The Impact of Temporal Aggregation of Land Surface Temperature Data for Urban Heat Island Monitoring

NASA Astrophysics Data System (ADS)

Hu, L.; Brunsell, N. A.

2012-12-01

Temporally composited remote sensing products are widely used in monitoring the urban heat island (UHI). In order to quantify the impact of temporal aggregation for assessing the UHI, we examined MODIS land surface temperature (LST) products for 11 years focusing on Houston, Texas and its surroundings. By using the daily LST from 2000 to 2010, the urban and rural daily LST were presented for the 8-day period and annual comparisons for both day and night. Statistics based on the rural-urban LST differences show that the 8-day composite mean UHI effects are generally more intensive than that calculated by daily UHI images. Moreover, the seasonal pattern shows that the summer daytime UHI has the largest magnitude and variation while nighttime UHI magnitudes are much smaller and less variable. Regression analyses enhance the results showing an apparently higher UHI derived from 8-day composite dataset. The summer mean UHI maps were compared, indicating a land cover related pattern. We introduced yearly MODIS land cover type product to explore the spatial differences caused by temporal aggression of LST product. The mean bias caused by land cover types are calculated about 0.5 ~ 0.7K during the daytime, and less than 0.1K at night. The potential causes of the higher UHI are discussed. The analysis shows that the land-atmosphere interactions, which result in the regional cloud formation, are the primary reason.

Determining urban land uses through building-associated element attributes derived from lidar and aerial photographs

NASA Astrophysics Data System (ADS)

Meng, Xuelian

Urban land-use research is a key component in analyzing the interactions between human activities and environmental change. Researchers have conducted many experiments to classify urban or built-up land, forest, water, agriculture, and other land-use and land-cover types. Separating residential land uses from other land uses within urban areas, however, has proven to be surprisingly troublesome. Although high-resolution images have recently become more available for land-use classification, an increase in spatial resolution does not guarantee improved classification accuracy by traditional classifiers due to the increase of class complexity. This research presents an approach to detect and separate residential land uses on a building scale directly from remotely sensed imagery to enhance urban land-use analysis. Specifically, the proposed methodology applies a multi-directional ground filter to generate a bare ground surface from lidar data, then utilizes a morphology-based building detection algorithm to identify buildings from lidar and aerial photographs, and finally separates residential buildings using a supervised C4.5 decision tree analysis based on the seven selected building land-use indicators. Successful execution of this study produces three independent methods, each corresponding to the steps of the methodology: lidar ground filtering, building detection, and building-based object-oriented land-use classification. Furthermore, this research provides a prototype as one of the few early explorations of building-based land-use analysis and successful separation of more than 85% of residential buildings based on an experiment on an 8.25-km2 study site located in Austin, Texas.

EnviroAtlas - New York, NY - One Meter Resolution Urban Land Cover Data (2008) Web Service

EPA Pesticide Factsheets

This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas ). The New York, NY EnviroAtlas Meter-scale Urban Land Cover (MULC) Data were generated by the University of Vermont Spatial Analysis Laboratory (SAL) under the direction of Jarlath O'Neil-Dunne as part of the United States Forest Service Urban Tree Canopy (UTC) assessment program. Seven classes were mapped using LiDAR and high resolution orthophotography: Tree Canopy, Grass/Shrub, Bare Soil, Water, Buildings, Roads/Railroads, and Other Paved Surfaces. These data were subsequently merged to fit with the EPA classification. The SAL project covered the five boroughs within the NYC city limits. However the EPA study area encompassed that area plus a 1 kilometer buffer. Additional land cover for the buffer area was generated from United States Department of Agriculture (USDA) National Agricultural Imagery Program (NAIP) four band (red, green, blue, and near infrared) aerial photography at 1 m spatial resolution from July, 2011 and LiDAR from 2010. Six land cover classes were mapped: water, impervious surfaces, soil and barren land, trees, grass-herbaceous non-woody vegetation, and agriculture. An accuracy assessment of 600 completely random and 55 stratified random photo interpreted reference points yielded an overall User's fuzzy accuracy of 87 percent. The area mapped is the US Census Bureau's 2010 Urban Statistical Area for New Yor

Monitoring urban land cover change by updating the national land cover database impervious surface products

USGS Publications Warehouse

Xian, George Z.; Homer, Collin G.

2009-01-01

The U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001 is widely used as a baseline for national land cover and impervious conditions. To ensure timely and relevant data, it is important to update this base to a more recent time period. A prototype method was developed to update the land cover and impervious surface by individual Landsat path and row. This method updates NLCD 2001 to a nominal date of 2006 by using both Landsat imagery and data from NLCD 2001 as the baseline. Pairs of Landsat scenes in the same season from both 2001 and 2006 were acquired according to satellite paths and rows and normalized to allow calculation of change vectors between the two dates. Conservative thresholds based on Anderson Level I land cover classes were used to segregate the change vectors and determine areas of change and no-change. Once change areas had been identified, impervious surface was estimated for areas of change by sampling from NLCD 2001 in unchanged areas. Methods were developed and tested across five Landsat path/row study sites that contain a variety of metropolitan areas. Results from the five study areas show that the vast majority of impervious surface changes associated with urban developments were accurately captured and updated. The approach optimizes mapping efficiency and can provide users a flexible method to generate updated impervious surface at national and regional scales.

Urban Sustainability and Public Health: Throwing the Bath Water Out and Not the Baby

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.

2009-01-01

This slide presentation reviews the affect of urbanization on community health. It exams urbanization trends in the Atlanta metro area and includes information on impervious surfaces, air quality, mitigation strategies, spatial growth modeling, land use, public health surveillance and different data collection methods.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snyder, M.A.; Kueppers, L.M.; Sloan, L.C.

In the western United States, more than 30,500 square miles has been converted to irrigated agriculture and urban areas. This study compares the climate responses of four regional climate models (RCMs) to these past land-use changes. The RCMs used two contrasting land cover distributions: potential natural vegetation, and modern land cover that includes agriculture and urban areas. Three of the RCMs represented irrigation by supplementing soil moisture, producing large decreases in August mean (-2.5 F to -5.6 F) and maximum (-5.2 F to -10.1 F) 2-meter temperatures where natural vegetation was converted to irrigated agriculture. Conversion to irrigated agriculture alsomore » resulted in large increases in relative humidity (9 percent 36 percent absolute change). Only one of the RCMs produced increases in summer minimum temperature. Converting natural vegetation to urban land cover produced modest but discernable climate effects in all models, with the magnitude of the effects dependent upon the preexisting vegetation type. Overall, the RCM results indicate that land use change impacts are most pronounced during the summer months, when surface heating is strongest and differences in surface moisture between irrigated land and natural vegetation are largest. The irrigation effect on summer maximum temperatures is comparable in magnitude (but opposite in sign) to predicted future temperature change due to increasing greenhouse gas concentrations.« less

Effects of Land Use/Cover Changes and Urban Forest Configuration on Urban Heat Islands in a Loess Hilly Region: Case Study Based on Yan'an City, China.

PubMed

Zhang, Xinping; Wang, Dexiang; Hao, Hongke; Zhang, Fangfang; Hu, Youning

2017-07-26

In this study Yan'an City, a typical hilly valley city, was considered as the study area in order to explain the relationships between the surface urban heat island (SUHI) and land use/land cover (LULC) types, the landscape pattern metrics of LULC types and land surface temperature (LST) and remote sensing indexes were retrieved from Landsat data during 1990-2015, and to find factors contributed to the green space cool island intensity (GSCI) through field measurements of 34 green spaces. The results showed that during 1990-2015, because of local anthropogenic activities, SUHI was mainly located in lower vegetation cover areas. There was a significant suburban-urban gradient in the average LST, as well as its heterogeneity and fluctuations. Six landscape metrics comprising the fractal dimension index, percentage of landscape, aggregation index, division index, Shannon's diversity index, and expansion intensity of the classified LST spatiotemporal changes were paralleled to LULC changes, especially for construction land, during the past 25 years. In the urban area, an index-based built-up index was the key positive factor for explaining LST increases, whereas the normalized difference vegetation index and modified normalized difference water index were crucial factors for explaining LST decreases during the study periods. In terms of the heat mitigation performance of green spaces, mixed forest was better than pure forest, and the urban forest configuration had positive effects on GSCI. The results of this study provide insights into the importance of species choice and the spatial design of green spaces for cooling the environment.

Effects of Land Use/Cover Changes and Urban Forest Configuration on Urban Heat Islands in a Loess Hilly Region: Case Study Based on Yan’an City, China

PubMed Central

Zhang, Xinping; Hao, Hongke; Zhang, Fangfang; Hu, Youning

2017-01-01

In this study Yan’an City, a typical hilly valley city, was considered as the study area in order to explain the relationships between the surface urban heat island (SUHI) and land use/land cover (LULC) types, the landscape pattern metrics of LULC types and land surface temperature (LST) and remote sensing indexes were retrieved from Landsat data during 1990–2015, and to find factors contributed to the green space cool island intensity (GSCI) through field measurements of 34 green spaces. The results showed that during 1990–2015, because of local anthropogenic activities, SUHI was mainly located in lower vegetation cover areas. There was a significant suburban-urban gradient in the average LST, as well as its heterogeneity and fluctuations. Six landscape metrics comprising the fractal dimension index, percentage of landscape, aggregation index, division index, Shannon’s diversity index, and expansion intensity of the classified LST spatiotemporal changes were paralleled to LULC changes, especially for construction land, during the past 25 years. In the urban area, an index-based built-up index was the key positive factor for explaining LST increases, whereas the normalized difference vegetation index and modified normalized difference water index were crucial factors for explaining LST decreases during the study periods. In terms of the heat mitigation performance of green spaces, mixed forest was better than pure forest, and the urban forest configuration had positive effects on GSCI. The results of this study provide insights into the importance of species choice and the spatial design of green spaces for cooling the environment. PMID:28933770

Assessing the relationship between surface urban heat islands and landscape patterns across climatic zones in China.

PubMed

Yang, Qiquan; Huang, Xin; Li, Jiayi

2017-08-24

The urban heat island (UHI) effect exerts a great influence on the Earth's environment and human health and has been the subject of considerable attention. Landscape patterns are among the most important factors relevant to surface UHIs (SUHIs); however, the relationship between SUHIs and landscape patterns is poorly understood over large areas. In this study, the surface UHI intensity (SUHII) is defined as the temperature difference between urban and suburban areas, and the landscape patterns are quantified by the urban-suburban differences in several typical landscape metrics (ΔLMs). Temperature and land-cover classification datasets based on satellite observations were applied to analyze the relationship between SUHII and ΔLMs in 332 cities/city agglomerations distributed in different climatic zones of China. The results indicate that SUHII and its correlations with ΔLMs are profoundly influenced by seasonal, diurnal, and climatic factors. The impacts of different land-cover types on SUHIs are different, and the landscape patterns of the built-up and vegetation (including forest, grassland, and cultivated land) classes have the most significant effects on SUHIs. The results of this study will help us to gain a deeper understanding of the relationship between the SUHI effect and landscape patterns.

Multitemporal analysis of Landsat images to detect land use land cover changes for monitoring soil sealing in the Nola area (Naples, Italy)

NASA Astrophysics Data System (ADS)

De Giglio, Michaela; Allocca, Maria; Franci, Francesca

2016-10-01

Land Use Land Cover Changes (LULCC) data provide objective information to support environmental policy, urban planning purposes and sustainable land development. Understanding of past land use/cover practices and current landscape patterns is critical to assess the effects of LULCC on the Earth system. Within the framework of soil sealing in Italy, the present study aims to assess the LULCC of the Nola area (Naples metropolitan area, Italy), relating to a thirty year period from 1984 to 2015. The urban sprawl affects this area causing the impervious surface increase, the loss in rural areas and landscape fragmentation. Located near Vesuvio volcano and crossed by artificial filled rivers, the study area is subject to landslide, hydraulic and volcanic risks. Landsat time series has been processed by means of the supervised per-pixel classification in order to produce multitemporal Land Use Land Cover maps. Then, post-classification comparison approach has been applied to quantify the changes occurring between 1984 and 2015, also analyzing the intermediate variations in 1999, namely every fifteen years. The results confirm the urban sprawl. The increase of the built-up areas mainly causes the habitat fragmentation and the agricultural land conversion of the Nola area that is already damaged by unauthorized disposal of urban waste. Moreover, considering the local risk maps, it was verified that some of the new urban areas were built over known hazardous sites. In order to limit the soil sealing, urgent measures and sustainable urban planning are required.

GLOBE students, teachers, and scientists demonstrate variable differences between urban and rural leaf phenology

Treesearch

Rico Gazal; Michael A. White; Robert Gillies; Eli Rodemakers; Elena Sparrow; Leslie Gordon

2008-01-01

The urban heat island effect, classically associated with high impervious surface area (ISA), low vegetation fractional cover (Fr), and high land surface temperature (LST), has been linked to changing patterns of vegetation phenology, especially spring growth. In this study, a collaboration with the Global Learning and Observations to Benefit the Environment (GLOBE)...

Influence of urbanization pattern on stream flow of a peri-urban catchment under Mediterranean climate

NASA Astrophysics Data System (ADS)

Ferreira, Carla S. S.; Walsh, Rory P. D.; Ferreira, António J. D.; Steenhuis, Tammo S.; Coelho, Celeste A. O.

2015-04-01

The demand for better life quality and lower living costs created a great pressure on peri-urban areas, leading to significant land-use changes. The complexity of mixed land-use patterns, however, presents a challenge to understand the hydrological pathways and streamflow response involved in such changes. This study assesses the impact of a actively changing Portuguese peri-urban area on catchment hydrology. It focuses on quantifying streamflow delivery from contributing areas, of different land-use arrangement and the seasonal influence of the Mediterranean climate on stream discharge. The study focuses on Ribeira dos Covões a small (6 km2) peri-urban catchment on the outskirts of Coimbra, one of the main cities in central Portugal. Between 1958 and 2012 the urban area of the catchment expanded from 8% to 40%, mostly at the expense of agriculture (down from 48% to 4%), with woodland now accounting for the remaining 56% of the catchment area. The urban area comprises contrasting urban settings, associated with older discontinuous arrangement of buildings and urban structures and low population density (<25 inhabitants/km), and recent well-defined urban cores dominated by apartment blocks and high population density (9900 inhabitants/km). The hydrological response of the catchment has been monitored since 2007 by a flume installed at the outlet. In 2009, five rainfall gauges and eight additional water level recorders were installed upstream, to assess the hydrological response of different sub-catchments, characterized by distinct urban patterns and either limestone or sandstone lithologies. Annual runoff coefficients range between 14% and 22%. Changes in annual baseflow index (36-39% of annual rainfall) have been small with urbanization (from 34% to 40%) during the monitoring period itself. Annual runoff coefficients were lowest (14-7%) on catchments >80% woodland and highest (29% on sandstone; 18% on limestone) in the most urbanized (49-53% urban) sub-catchments. Percentage impermeable surface seems to control streamflow particularly during dry periods. Winter runoff was 2-4 times higher than total river flow in the summer dry season in highly urbanized areas, but was 21-fold higher in winter in the least urbanized sub-catchment, denoting greater flow connectivity enhanced by increased soil moisture. Although impermeable surfaces are prone to generate overland flow, the proximity to the stream network is an important parameter determining their hydrological impacts. During the monitoring period, the enlargement of 2% of the urban area at downslope locations in the Covões sub-catchment, led to a 6% increase in the runoff coefficient. In contrast, the urban area increase from 9 to 25% mainly in upslope parts of the Quinta sub-catchment did not increase the peak streamflow due to downslope infiltration and surface retention opportunities. Despite impermeable surfaces enhance overland flow, some urban features (e.g. walls and road embankments) promote surface water retention. The presence of artificial drainage systems, on the other hand, enhances flow connectivity, leading to increasing peak flow and quicker response times (~10 minutes versus 40-50 minutes) as in the Covões sub-catchment. Urbanization impact on streamflow responses may be minimized through planning the land-use mosaic so as to maximize infiltration opportunities. Knowledge of the influence of distinct urban mosaics on flow connectivity and stream discharge is therefore important to landscape managers and should guide urban planning in order to minimize flood hazards.

Mapping 2000 2010 Impervious Surface Change in India Using Global Land Survey Landsat Data

NASA Technical Reports Server (NTRS)

Wang, Panshi; Huang, Chengquan; Brown De Colstoun, Eric C.

2017-01-01

Understanding and monitoring the environmental impacts of global urbanization requires better urban datasets. Continuous field impervious surface change (ISC) mapping using Landsat data is an effective way to quantify spatiotemporal dynamics of urbanization. It is well acknowledged that Landsat-based estimation of impervious surface is subject to seasonal and phenological variations. The overall goal of this paper is to map 200-02010 ISC for India using Global Land Survey datasets and training data only available for 2010. To this end, a method was developed that could transfer the regression tree model developed for mapping 2010 impervious surface to 2000 using an iterative training and prediction (ITP) approach An independent validation dataset was also developed using Google Earth imagery. Based on the reference ISC from the validation dataset, the RMSE of predicted ISC was estimated to be 18.4%. At 95% confidence, the total estimated ISC for India between 2000 and 2010 is 2274.62 +/- 7.84 sq km.

Parameter Estimation and Sensitivity Analysis of an Urban Surface Energy Balance Parameterization at a Tropical Suburban Site

NASA Astrophysics Data System (ADS)

Harshan, S.; Roth, M.; Velasco, E.

2014-12-01

Forecasting of the urban weather and climate is of great importance as our cities become more populated and considering the combined effects of global warming and local land use changes which make urban inhabitants more vulnerable to e.g. heat waves and flash floods. In meso/global scale models, urban parameterization schemes are used to represent the urban effects. However, these schemes require a large set of input parameters related to urban morphological and thermal properties. Obtaining all these parameters through direct measurements are usually not feasible. A number of studies have reported on parameter estimation and sensitivity analysis to adjust and determine the most influential parameters for land surface schemes in non-urban areas. Similar work for urban areas is scarce, in particular studies on urban parameterization schemes in tropical cities have so far not been reported. In order to address above issues, the town energy balance (TEB) urban parameterization scheme (part of the SURFEX land surface modeling system) was subjected to a sensitivity and optimization/parameter estimation experiment at a suburban site in, tropical Singapore. The sensitivity analysis was carried out as a screening test to identify the most sensitive or influential parameters. Thereafter, an optimization/parameter estimation experiment was performed to calibrate the input parameter. The sensitivity experiment was based on the "improved Sobol's global variance decomposition method" . The analysis showed that parameters related to road, roof and soil moisture have significant influence on the performance of the model. The optimization/parameter estimation experiment was performed using the AMALGM (a multi-algorithm genetically adaptive multi-objective method) evolutionary algorithm. The experiment showed a remarkable improvement compared to the simulations using the default parameter set. The calibrated parameters from this optimization experiment can be used for further model validation studies to identify inherent deficiencies in model physics.

The summer urban heat island of Bucharest (Romania) as retrieved from satellite imagery

NASA Astrophysics Data System (ADS)

Cheval, Sorin; Dumitrescu, Alexandru

2014-05-01

The summer Urban Heat Island (UHI) of the city of Bucharest (Romania) has been investigated in terms of its shape, intensity, extension, and links to land cover. The study integrates land surface temperature (LST) data retrieved by the MODIS sensors aboard the Terra and Aqua NASA satellites, and SEVIRI sensors on board of the geostationary platform MSG, along 2000-2012. Based on the Rodionov Regime Shift Index, the significant changing points in the land surface temperature values along transverse profiles crossing the city's centre were considered as UHI's limits. The study shows that the intensity calculated as the difference between the LST within the UHI limits and several surrounding buffers is an objective and flexible tool for describing the average thermal state of the urban-rural transition. The method secures the weight of comparing the UHI's intensity of different urban areas. There are little variations from one month to another, but UHI's shapes and intensities under clear-sky conditions are very specific to nighttime (more regular and 2-3°C less in the 7-km width buffer), and daytime (more twisted and more steep temperature decrease). For both cases, strong relationships with the land cover can be assumed. The nighttime UHI's geometry is more regular, and the intensity lower than the day situation, while the land cover exerts a strong influence on the Bucharest LST. After all, the study promotes an objective manner to delimitate and quantify the UHI based on satellite imagery. The study was performed within the STAR project 92/2013 (Urban Heat Island Monitoring under Present and Future Climate - UCLIMESA).

Climatic effects of 30 years of landscape change over the Greater Phoenix, Arizona, region: 1. Surface energy budget changes

USGS Publications Warehouse

Georgescu, M.; Miguez-Macho, G.; Steyaert, L.T.; Weaver, C.P.

2009-01-01

This paper is part 1 of a two-part study that evaluates the climatic effects of recent landscape change for one of the nation's most rapidly expanding metropolitan complexes, the Greater Phoenix, Arizona, region. The region's landscape evolution over an approximate 30-year period since the early 1970s is documented on the basis of analyses of Landsat images and land use/land cover (LULC) data sets derived from aerial photography (1973) and Landsat (1992 and 2001). High-resolution, Regional Atmospheric Modeling System (RAMS), simulations (2-km grid spacing) are used in conjunction with consistently defined land cover data sets and associated biophysical parameters for the circa 1973, circa 1992, and circa 2001 time periods to quantify the impacts of intensive land use changes on the July surface temperatures and the surface radiation and energy budgets for the Greater Phoenix region. The main findings are as follows: since the early 1970s the region's landscape has been altered by a significant increase in urban/suburban land area, primarily at the expense of decreasing plots of irrigated agriculture and secondarily by the conversion of seminatural shrubland. Mean regional temperatures for the circa 2001 landscape were 0.12??C warmer than the circa 1973 landscape, with maximum temperature differences, located over regions of greatest urbanization, in excess of 1??C. The significant reduction in irrigated agriculture, for the circa 2001 relative to the circa 1973 landscape, resulted in dew point temperature decreases in excess of 1??C. The effect of distinct land use conversion themes (e.g., conversion from irrigated agriculture to urban land) was also examined to evaluate how the most important conversion themes have each contributed to the region's changing climate. The two urbanization themes studied (from an initial landscape of irrigated agriculture and seminatural shrubland) have the greatest positive effect on near-surface temperature, increasing maximum daily temperatures by 1??C. Overall, sensible heat flux differences between the circa 2001 and circa 1973 landscapes result in a 1 W m-2 increase in domain-wide sensible heating, and a similar order of magnitude decrease in latent heating, highlighting the importance of surface repartitioning in establishing near-surface temperature trends. In part 2 of this study, we address the role of the surface budget changes on the mesoscale dynamics/thermodynamics, in context of the large-scale environment. Copyright 2009 by the American Geophysical Union.

Using the storm water management model to predict urban headwater stream hydrological response to climate and land cover change

Treesearch

J.Y. Wu; J.R. Thompson; R.K. Kolka; K.J. Franz; T.W. Stewart

2013-01-01

Streams are natural features in urban landscapes that can provide ecosystem services for urban residents. However, urban streams are under increasing pressure caused by multiple anthropogenic impacts, including increases in human population and associated impervious surface area, and accelerated climate change. The ability to anticipate these changes and better...

A modeling study on the effect of urban land surface forcing to regional meteorology and air quality over South China

NASA Astrophysics Data System (ADS)

Zhu, Kuanguang; Xie, Min; Wang, Tijian; Cai, Junxiong; Li, Songbing; Feng, Wen

2017-03-01

The change of land-use from natural to artificial surface induced by urban expansion can deeply impact the city environment. In this paper, the model WRF/Chem is applied to explore the effect of this change on regional meteorology and air quality over South China, where people have witnessed a rapid rate of urbanization. Two sets of urban maps are adopted to stand for the pre-urbanization and the present urban land-use distributions. Month-long simulations are conducted for January and July, 2014. The results show that urban expansion can obviously change the weather conditions around the big cities of South China. Especially in the Pearl River Delta region (PRD), the urban land-use change can increase the sensible heat flux by 40 W/m2 in January and 80 W/m2 in July, while decrease the latent heat flux about -50 W/m2 in January and -120 W/m2 in July. In the consequent, 2-m air temperature (T2) increases as much as 1 °C and 2 °C (respective to January and July), planetary boundary layer height (PBLH) rises up by 100-150 m and 300 m, 10-m wind speed (WS10) decreases by -1.2 m/s and -0.3 m/s, and 2-m specific humidity is reduced by -0.8 g/kg and -1.5 g/kg. Also, the precipitation in July can be increased as much as 120 mm, with more heavy rains and rainstorms. These variations of meteorological factors can significantly impact the spatial and vertical distribution of air pollutants as well. In PRD, the enhanced updraft can reduce the surface concentrations of PM10 by -40 μg/m3 (30%) in January and -80 μg/m3 (50%) in July, but produce a correlating increase in the concentrations at higher atmospheric layers. However, according to the increase in T2 and the decrease in surface NO, the surface concentrations of O3 in PRD can increase by 2-6 ppb in January and 8-12 ppb in July. Meanwhile, there is a significant increase in the O3 concentrations at upper layers above PRD, which should be attributed to the increase in air temperature and the enhanced upward transport of O3 and its precursors. As for some relative small cities, such as Haikou, there is very little variation in surface PM10 and O3 in both months, implying less urbanization in these areas. Moreover, the depletion of O3 by NO may be the main cause of the reduction of O3 at upper layers in these small cities.

Can Aerosol Offset Urban Heat Island Effect?

NASA Astrophysics Data System (ADS)

Jin, M. S.; Shepherd, J. M.

2009-12-01

The Urban Heat Island effect (UHI) refers to urban skin or air temperature exceeding the temperatures in surrounding non-urban regions. In a warming climate, the UHI may intensify extreme heat waves and consequently cause significant health and energy problems. Aerosols reduce surface insolation via the direct effect, namely, scattering and absorbing sunlight in the atmosphere. Combining the National Aeronautics and Space Administration (NASA) AERONET (AErosol RObotic NETwork) observations over large cities together with Weather Research and Forecasting Model (WRF) simulations, we find that the aerosol direct reduction of surface insolation range from 40-100 Wm-2, depending on seasonality and aerosol loads. As a result, surface skin temperature can be reduced by 1-2C while 2-m surface air temperature by 0.5-1C. This study suggests that the aerosol direct effect is a competing mechanism for the urban heat island effect (UHI). More importantly, both aerosol and urban land cover effects must be adequately represented in meteorological and climate modeling systems in order to properly characterize urban surface energy budgets and UHI.

[Research on spatial differentiation of urban stormwater runoff quality by source area monitoring].

PubMed

Li, Li-Qing; Zhu, Ren-Xiao; Guo, Shu-Gang; Yin, Cheng-Qing

2010-12-01

Runoff samples were collected from 14 source areas in Hanyang district during four rain events in an attempt to investigate the spatial differentiation and influencing factors of urban stormwater runoff quality. The outcomes are expected to offer practical guidance in sources control of urban runoff pollution. The results revealed that particle-bound proportion of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in stormwater runoff were 58% +/- 17%, 65% +/- 13% and 92% +/- 6%, respectively. The fractions of ammonia, nitrate and dissolved organic nitrogen were homogeneous in dissolved nitrogen composition. Urban surface function, traffic volume, land use, population density, and street sweeping practice are the main factors determining spatial differentiation of urban surface runoff quality. The highest magnitude of urban stormwater runoff pollution was expected in the old urban residential area, followed by general residential with restaurants, commercial and transport area, new developments and green land. In addition, the magnitude of road stormwater runoff pollution is positively correlated to traffic volume, in the following order: the first trunk road > the second trunk road > minor road. Street sweeping and critical source areas controls should be implemented to mitigate the adverse effects of urban stormwater runoff on receive waters.

Estimating Urban Gross Primary Productivity at High Spatial Resolution

NASA Astrophysics Data System (ADS)

Miller, David Lauchlin

Gross primary productivity (GPP) is an important metric of ecosystem function and is the primary way carbon is transferred from the atmosphere to the land surface. Remote sensing techniques are commonly used to estimate regional and global GPP for carbon budgets. However, urban areas are typically excluded from such estimates due to a lack of parameters specific to urban vegetation and the modeling challenges that arise in mapping GPP across heterogeneous urban land cover. In this study, we estimated typical midsummer GPP within and among vegetation and land use types in the Minneapolis-Saint Paul, Minnesota metropolitan region by deriving light use efficiency parameters specific to urban vegetation types using in situ flux observations and WorldView-2 high spatial resolution satellite imagery. We produced a land cover classification using the satellite imagery, canopy height data from airborne lidar, and leaf-off color-infrared aerial orthophotos, and used regional GIS layers to mask certain land cover/land use types. The classification for built-up and vegetated urban land cover classes distinguished deciduous trees, evergreen trees, turf grass, and golf grass from impervious and soil surfaces, with an overall classification accuracy of 80% (kappa = 0.73). The full study area had 52.1% vegetation cover. The light use efficiency for each vegetation class, with the exception of golf grass, tended to be low compared to natural vegetation light use efficiencies in the literature. The mapped GPP estimates were within 11% of estimates from independent tall tower eddy covariance measurements. The order of the mapped vegetation classes for the full study area in terms of mean GPP from lowest to highest was: deciduous trees (2.52 gC m -2 d-1), evergreen trees (5.81 gC m-2 d-1), turf grass (6.05 gC m-2 d-1), and golf grass (11.77 gC m-2 d-1). Turf grass GPP had a larger coefficient of variation (0.18) than the other vegetation classes (˜0.10). Mean land use GPP for the full study area varied as a function of percent vegetation cover. Urban GPP in general, both including and excluding non-vegetated areas, tended to be low relative to natural forests and grasslands. Our results demonstrate that, at the scale of neighborhoods and city blocks within heterogeneous urban landscapes, high spatial resolution GPP estimates are valuable to develop comparisons such as within and among vegetation cover classes and land use types.

Change of Impervious Surface Area Between 2001 and 2006 in the Conterminous United States

EPA Science Inventory

Land cover and land use change have long been recognized as an important driver of past and present ecosystem change, especially when considering terrestrial biodiversity loss in human-dominated regions (IPCC, 2007). Urban land cover is an important component of regional and glob...

Physical and Biological Impacts of Changing Land-Uses and the Environment

NASA Astrophysics Data System (ADS)

English, W. R.; Pike, J. W.; Jolley, L. W.; Goddard, M. A.; Biondi, M. J.; Hur, J. M.; Powell, B. A.; Morse, J. C.

2005-05-01

A goal of the Changing Land Use and the Environment (CLUE) project is to characterize surface water quality impacted by land-use change in the Saluda and Reedy River watersheds of South Carolina. The CLUE project focuses on impacts common to urban development including 1. sedimentation from construction sites, 2. alteration of discharge and channel morphology due to increased impervious surfaces, 3. macroinvertebrate community response to sedimentation and habitat alteration, and 4. microbial contamination. We found that mean streambed particle size was reduced in developing areas. Stream cross-sectional areas enlarged in catchments with high percentages of impervious surfaces. Sedimentation and altered discharge resulted in the benthic macroinvertebrate community showing a general reduction in biotic integrity values and reductions in Plecoptera taxa richness. Fecal coliform levels were higher for both surface water and bottom sediments in and below urbanized areas during base flows. Levels of fecal coliform in samples collected during storm flows were significantly higher than in base flows, and were correlated with high sediment loads.

Relationships between landscape pattern and land surface temperature and their applications to the study of West Nile Virus: As case studies in cities of Indianapolis and Chicago, United States

NASA Astrophysics Data System (ADS)

Liu, Hua

A new synthesis of remote sensing and landscape ecology approaches was developed to establish relationships between the landscape patterns and land surface temperatures (LST) in the city of Indianapolis, Indiana, United States. Land use and land cover (LULC) and LST images were derived from Terra Satellite's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery. An analytical procedure using landscape metrics was developed, applying configuration analysis of landscape patterns and land surface temperature zones. Detailed landscape pattern analyses at the landscape and class scales were conducted using landscape metrics in the City of Indianapolis. The effects of spatial resolution on the identification of the relationship were examined in the same city. The best level of equalization between the LULC and LST maps was determined based on minimum distance analysis in landscape metrics space. The analyses of relationships between the landscape patterns and land surface temperatures, and scaling effects were applied to the spread of West Nile Virus (WNV) in the City of Chicago, Illinois. Results show that urban, forest, and grassland were the main landscape components in Indianapolis. They possessed relatively higher fractal dimensions but lower spatial aggregation levels in April 5, 2004, June 16, 2001, and October 3, 2000, but not in February 6, 2006. Obvious seasonal differences existed with the most distinct landscape pattern detected on February 6, 2006. Urban was the dominant LULC type in high-temperature zones, while water and vegetation mainly fell in low-temperature zones. For each individual date, the metrics of LST zones apparently corresponded to the metrics of LULC types. In the study of scaling-up effect analysis, Patch Percentage, Patch Density, and Landscape Shape index were found to be able to effectively quantify the spatial changes of LULC types and temperature zones at different scales without contradiction. Urban, forest, and grassland in each season were more easily affected by the process in Patch Density and Landscape Shape index. Ninety meters was believed to be the optimal spatial resolution to examine relationships between landscape patterns and LSTs in the City of Indianapolis. In the study of the spread of West Nile Virus in the City of Chicago, WNV was found to have been spread throughout all of Cook County since 2001. Landscape factors, like landscape aggregation index and areas of urban, grass, and water showed a strong correlation with the number of WNV infections. Socioeconomic conditions, like population above 65 years old also showed a strong relationship with the spread of WNV in Cook County. Thermal conditions of water had a lower but still significant correlation to the spread of WNV. This research offers an opportunity to explore the mechanism of interaction between urban landscape patterns and land surface temperatures at different spatial scales, and show the effects of landscape pattern and land surface temperature on the spread of West Nile Virus. This study can be useful for urban planning and environmental management practices in the studied areas. It also contributes to public health management and protection.

Nocturnal Propagating Thunderstorms May Favor Urban "Hot-Spots": A Model-Based Study over Minneapolis

NASA Technical Reports Server (NTRS)

Ganeshan, Manisha; Murtugudde, Raghu

2015-01-01

High-resolution WRF model sensitivity experiments are carried out (with and without urban land cover) to study urban impacts on nocturnal propagating thunderstorms over the city of Minneapolis. It is found that the storm spatial characteristics, especially the position of the storm cell, are appreciably altered by the presence of urban land cover. The most robust urban instability during stormy conditions is the enhanced surface convergence due to increased frictional drag. No urban impact is visible on the rainfall intensity simulated by the model. The frictional convergence, aided by the nocturnal Urban Heat Island (UHI), appears to be responsible for attracting propagating storms towards the urban center. Advanced modeling experiments are needed to quantify the mechanical and thermal influence along with similar studies in other cities to further investigate the urban impact on the frequency and trajectory of nocturnal propagating storms.

Impacts of urban landscape patterns on urban thermal variations in Guangzhou, China

NASA Astrophysics Data System (ADS)

Chen, Youjun; Yu, Shixiao

2017-02-01

One of the key impacts of rapid urbanization on the environment is the effect of surface urban thermal variations (SUTV). Understanding the effects of urban landscape features on SUTV is crucial for improving the ecology and sustainability of cities. In this study, an investigation was conducted to detect urban landscape patterns and assess their impact on surface temperature. Landsat images: Thematic Mapper was used to calculate land surface temperature (LST) in Guangzhou, the capital city of Guangdong Province in southern China. SUTV zones, including surface urban heat islands (SUHI) and surface urban heat sinks (SUHS), were then empirically identified. The composition and configuration of landscape patterns were measured by a series of spatial metrics at the class and landscape levels in the SUHI and SUHS zones. How both landscape composition and configuration influence urban thermal characteristics was then analysed. It was found that landscape composition has the strongest effect on SUTV, but that urban landscape configuration also influences SUTV. These findings are helpful for achieving a comprehensive understanding of how urban landscape patterns impact SUTV and can help in the design of effective urban landscape patterns to minimize the effects of SUHI.

Evaluating relationships between urban land cover composition and evapotranspiration in semi-arid regions

NASA Astrophysics Data System (ADS)

Manago, K. F.; Hogue, T. S.; Litvak, E.; Pataki, D. E.

2016-12-01

California experienced its most severe drought on record in 2013 and 2014, forcing the governor to call for the first statewide reductions in urban water use. This led to numerous water conservation efforts including turf removal and restrictions on outdoor irrigation. The decrease in irrigation across the city of Los Angeles has had major effects on regional hydrologic fluxes. Previous studies have found that conservation efforts have decreased streamflow but little work has been done on the impact of reduced irrigation on Evapotranspiration (ET). ET is one of the most difficult variables to measure as a result of its heterogeneity both spatially and temporally; yet, it is imperative in characterizing energy and hydrologic processes and in aiding water management decisions. Estimating ET is further complicated in urban regions where land cover composition is extremely variable, even at small scales. Irrigated landscape and impervious surfaces are two of the most common land cover types associated with urbanization, but they have opposite effects on ET. While numerous studies have evaluated changes in ET caused by urbanization, they have all produced varying results. This is expected as changes to ET are highly dependent on land cover composition. In this study, we modeled the relationship between ET and urban land cover change in Los Angeles. We utilized empirical equations derived from in situ measurements to calculate tree and irrigated turfgrass ET and compared the results to estimates based on remote-sensing and California Irrigation Management Information System (CIMIS) network of weather stations. We found that unshaded turfgrass largely increased ET compared to impervious surfaces, which reveals lavish irrigation practices. Trees also increased ET, but they provided shade that decreased ET from turf grass. With much of the western United States facing drought and water supply uncertainty due to climate change, understanding and predicting how land cover impacts ET under various scenarios is imperative for informed water management and efficient conservation solutions.

Characterizing Urban Volumetry Using LIDAR Data

NASA Astrophysics Data System (ADS)

Santos, T.; Rodrigues, A. M.; Tenedório, J. A.

2013-05-01

Urban indicators are efficient tools designed to simplify, quantify and communicate relevant information for land planners. Since urban data has a strong spatial representation, one can use geographical data as the basis for constructing information regarding urban environments. One important source of information about the land status is imagery collected through remote sensing. Afterwards, using digital image processing techniques, thematic detail can be extracted from those images and used to build urban indicators. Most common metrics are based on area (2D) measurements. These include indicators like impervious area per capita or surface occupied by green areas, having usually as primary source a spectral image obtained through a satellite or airborne camera. More recently, laser scanning data has become available for large-scale applications. Such sensors acquire altimetric information and are used to produce Digital Surface Models (DSM). In this context, LiDAR data available for the city is explored along with demographic information, and a framework to produce volumetric (3D) urban indexes is proposed, and measures like Built Volume per capita, Volumetric Density and Volumetric Homogeneity are computed.

An Investigation of the Influence of Urban Areas on Rainfall Using a Cloud-Mesoscale Model and the TRMM Satellite

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Starr, David O'C (Technical Monitor)

2001-01-01

A recent paper by Shepherd and Pierce (conditionally accepted to Journal of Applied Meteorology) used rainfall data from the Precipitation Radar on NASA's Tropical Rainfall Measuring Mission's (TRMM) satellite to identify warm season rainfall anomalies downwind of major urban areas. A convective-mesoscale model with extensive land-surface processes is employed to (a) determine if an urban heat island (UHI) thermal perturbation can induce a dynamic response to affect rainfall processes and (b) quantify the impact of the following three factors on the evolution of rainfall: (1) urban surface roughness, (2) magnitude of the UHI temperature anomaly, and (3) physical size of the UHI temperature anomaly. The sensitivity experiments are achieved by inserting a slab of land with urban properties (e.g. roughness length, albedo, thermal character) within a rural surface environment and varying the appropriate lower boundary condition parameters. Early analysis suggests that urban surface roughness (through turbulence and low-level convergence) may control timing and initial location of UHI-induced convection. The magnitude of the heat island appears to be closely linked to the total rainfall amount with minor impact on timing and location. The physical size of the city may predominantly impact on the location of UHI-induced rainfall anomaly. The UHI factor parameter space will be thoroughly investigated with respect to their effects on rainfall amount, location, and timing. This study extends prior numerical investigations of the impact of urban surfaces on meteorological processes, particularly rainfall development. The work also contains several novel aspects, including the application of a high-resolution (less than I km) cloud-mesoscale model to investigate urban-induce rainfall process; investigation of thermal magnitude of the UHI on rainfall process; and investigation of UHI physical size on rainfall processes.

Impacts from Land Use Pattern on Spatial Distribution of Cultivated Soil Heavy Metal Pollution in Typical Rural-Urban Fringe of Northeast China

PubMed Central

Li, Wenbo; Wang, Dongyan; Wang, Qing; Liu, Shuhan; Zhu, Yuanli; Wu, Wenjun

2017-01-01

Under rapid urban sprawl in Northeast China, land conversions are not only encroaching on the quantity of cultivated lands, but also posing a great threat to black soil conservation and food security. This study’s aim is to explore the spatial relationship between comprehensive cultivated soil heavy metal pollution and peri-urban land use patterns in the black soil region. We applied spatial lag regression to analyze the relationship between PLI (pollution load index) and influencing factors of land use by taking suburban cultivated land of Changchun Kuancheng District as an empirical case. The results indicate the following: (1) Similar spatial distribution characteristics are detected between Pb, Cu, and Zn, between Cr and Ni, and between Hg and Cd. The Yitong River catchment in the central region, and the residential community of Lanjia County in the west, are the main hotspots for eight heavy metals and PLI. Beihu Wetland Park, with a larger-area distribution of ecological land in the southeast, has low level for both heavy metal concentrations and PLI values. Spatial distribution characteristics of cultivated heavy metals are related to types of surrounding land use and industry; (2) Spatial lag regression has a better fit for PLI than the ordinary least squares regression. The regression results indicate the inverse relationship between heavy metal pollution degree and distance from long-standing residential land and surface water. Following rapid urban land expansion and a longer accumulation period, residential land sprawl is going to threaten cultivated land with heavy metal pollution in the suburban black soil region, and cultivated land irrigated with urban river water in the suburbs will have a higher tendency for heavy metal pollution. PMID:28327541

Impacts from Land Use Pattern on Spatial Distribution of Cultivated Soil Heavy Metal Pollution in Typical Rural-Urban Fringe of Northeast China.

PubMed

Li, Wenbo; Wang, Dongyan; Wang, Qing; Liu, Shuhan; Zhu, Yuanli; Wu, Wenjun

2017-03-22

Under rapid urban sprawl in Northeast China, land conversions are not only encroaching on the quantity of cultivated lands, but also posing a great threat to black soil conservation and food security. This study's aim is to explore the spatial relationship between comprehensive cultivated soil heavy metal pollution and peri-urban land use patterns in the black soil region. We applied spatial lag regression to analyze the relationship between PLI (pollution load index) and influencing factors of land use by taking suburban cultivated land of Changchun Kuancheng District as an empirical case. The results indicate the following: (1) Similar spatial distribution characteristics are detected between Pb, Cu, and Zn, between Cr and Ni, and between Hg and Cd. The Yitong River catchment in the central region, and the residential community of Lanjia County in the west, are the main hotspots for eight heavy metals and PLI. Beihu Wetland Park, with a larger-area distribution of ecological land in the southeast, has low level for both heavy metal concentrations and PLI values. Spatial distribution characteristics of cultivated heavy metals are related to types of surrounding land use and industry; (2) Spatial lag regression has a better fit for PLI than the ordinary least squares regression. The regression results indicate the inverse relationship between heavy metal pollution degree and distance from long-standing residential land and surface water. Following rapid urban land expansion and a longer accumulation period, residential land sprawl is going to threaten cultivated land with heavy metal pollution in the suburban black soil region, and cultivated land irrigated with urban river water in the suburbs will have a higher tendency for heavy metal pollution.

Quantification and Mitigation of Long-Term Impacts of Urbanization and Climate Change in the Tropical Coastal City of San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Comarazamy, Daniel; Gonzalez, Jorge E.; Luvall, Jeffrey C.

2014-01-01

Urbanization, along with other cases of land cover and land use changes, has significant climate impacts in tropical regions with the added complexity of occurring within the context of global warming. The individual and combined effects of these two factors on the surface energy balance of a tropical city are investigated by use of an integrated atmospheric modeling approach, taking the San Juan Metropolitan Area (SJMA), Puerto Rico as the test case. To achieve this goal, an ensemble of climate and weather simulations is performed, with the climate scenarios combining urban development and sprawl with regional climate change over the past 50 years, and the short-term simulations designed to test the sensitivity to different urban vegetation configurations as mitigating alternatives. As indicator of change, we use the thermal response number (TRN), which is a measure of the sensible heating to the thermal storage of a surface or region, and the Bowen ratio, which is defined as the ratio of sensible to latent heat fluxes. The TRN of the area occupied by the SJMA has decreased as a consequence of replacing the low land coastal plain vegetation with man made materials, indicating that it takes less energy to raise the surface temperature of the urban area, whereas the TRN of forested regions has remained virtually unchanged. The global warming signal also has effects on the thermal response of the SJMA, where dryer current conditions generate lower TRN values. Differences due to global warming are more evident in the Bowen ratio pattern, mostly associated with the drier present conditions observed and its effects on sensible and latent heat fluxes. In terms of testing different mitigation strategies, the short-term simulations show that the urban area is more efficient in partitioning surface energy balance terms when green roofs are specified, as opposed to including vegetation inside the urban core.

Assessing the link between coastal urbanization and the quality of nekton habitat in mangrove tidal tributaries

USGS Publications Warehouse

Krebs, Justin M.; Bell, Susan S.; McIvor, Carole C.

2014-01-01

To assess the potential influence of coastal development on habitat quality for estuarine nekton, we characterized body condition and reproduction for common nekton from tidal tributaries classified as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). We then evaluated these metrics of nekton performance, along with several abundance-based metrics and community structure from a companion paper (Krebs et al. 2013) to determine which metrics best reflected variation in land-use and in-stream habitat among tributaries. Body condition was not significantly different among undeveloped, industrial, and man-made tidal tributaries for six of nine taxa; however, three of those taxa were in significantly better condition in urban compared to undeveloped tributaries. Palaemonetes shrimp were the only taxon in significantly poorer condition in urban tributaries. For Poecilia latipinna, there was no difference in body condition (length–weight) between undeveloped and urban tributaries, but energetic condition was significantly better in urban tributaries. Reproductive output was reduced for both P. latipinna (i.e., fecundity) and grass shrimp (i.e., very low densities, few ovigerous females) in urban tributaries; however a tradeoff between fecundity and offspring size confounded meaningful interpretation of reproduction among land-use classes for P. latipinna. Reproductive allotment by P. latipinna did not differ significantly among land-use classes. Canonical correspondence analysis differentiated urban and non-urban tributaries based on greater impervious surface, less natural mangrove shoreline, higher frequency of hypoxia and lower, more variable salinities in urban tributaries. These characteristics explained 36 % of the variation in nekton performance, including high densities of poeciliid fishes, greater energetic condition of sailfin mollies, and low densities of several common nekton and economically important taxa from urban tributaries. While variation among tributaries in our study can be largely explained by impervious surface beyond the shorelines of the tributary, variation in nekton metrics among non-urban tributaries was better explained by habitat factors within the tributary and along the shorelines. Our results support the paradigm that urban development in coastal areas has the potential to alter habitat quality in small tidal tributaries as reflected by variation in nekton performance among tributaries from representative land-use classes.

Evaluating the effects of historical land cover change on summertime weather and climate in New Jersey

NASA Astrophysics Data System (ADS)

Wichansky, Paul Stuart

The 19th-century agrarian landscape of New Jersey (NJ) and the surrounding region has been extensively transformed to the present-day land cover by urbanization, reforestation, and localized areas of deforestation. This study used a mesoscale atmospheric numerical model to investigate the sensitivity of the warm season climate of NJ to these land cover changes. Reconstructed 1880s-era and present-day land cover datasets were used as surface boundary conditions for a set of simulations performed with the Regional Atmospheric Modeling System (RAMS). Three-member ensembles with historical and present-day land cover were compared to examine the sensitivity of surface air and dewpoint temperatures, rainfall, the individual components of the surface energy budget, horizontal and vertical winds, and the vertical profiles of temperature and humidity to these land cover changes. Mean temperatures for the present-day landscape were 0.3-0.6°C warmer than for the historical landscape over a considerable portion of NJ and the surrounding region, with daily maximum temperatures at least 1.0°C warmer over some of the highly urbanized locations. Reforested regions in the present-day landscape, however, showed a slight cooling. Surface warming was generally associated with repartitioning of net radiation from latent to sensible heat flux, and conversely for cooling. Reduced evapotranspiration from much of the present-day land surface led to dewpoint temperature decreases of 0.3-0.6°C. While urbanization was accompanied by strong surface albedo decreases and increases in net shortwave radiation, reforestation and potential changes in forest composition have generally increased albedos and also enhanced landscape heterogeneity. The increased deciduousness of forests may have further reduced net downward longwave radiation. These land cover changes have modified boundary-layer dynamics by increasing low-level convergence and upper-level divergence in the interior of NJ, especially where sensible heat fluxes have increased for the present-day landscape, hence enhancing uplift in the mid-troposphere. The mesoscale circulations that developed in the present-day ensemble were also more effective at lifting available moisture to higher levels of the boundary layer, lowering dewpoints near the surface but increasing them aloft. Likewise, the sea breeze in coastal areas of NJ in the present-day ensemble had stronger uplift during the afternoon and enhanced moisture transport to higher levels.

Managed Clearings: an Unaccounted Land-cover in Urbanizing Regions

NASA Astrophysics Data System (ADS)

Singh, K. K.; Madden, M.; Meentemeyer, R. K.

2016-12-01

Managed clearings (MC), such as lawns, public parks and grassy transportation medians, are a common and ecologically important land cover type in urbanizing regions, especially those characterized by sprawl. We hypothesize that MC is underrepresented in land cover classification schemes and data products such as NLCD (National Land Cover Database) data, which may impact environmental assessments and models of urban ecosystems. We visually interpreted and mapped fine scale land cover with special attention to MC using 2012 NAIP (National Agriculture Imagery Program) images and compared the output with NLCD data. Areas sampled were 50 randomly distributed 1*1km blocks of land in three cities of the Char-lanta mega-region (Atlanta, Charlotte, and Raleigh). We estimated the abundance of MC relative to other land cover types, and the proportion of land-cover types in NLCD data that are similar to MC. We also assessed if the designations of recreation, transportation, and utility in MC inform the problem differently than simply tallying MC as a whole. 610 ground points, collected using the Google Earth, were used to evaluate accuracy of NLCD data and visual interpretation for consistency. Overall accuracy of visual interpretation and NLCD data was 78% and 58%, respectively. NLCD data underestimated forest and MC by 14.4km2 and 6.4km2, respectively, while overestimated impervious surfaces by 10.2km2 compared to visual interpretation. MC was the second most dominant land cover after forest (40.5%) as it covered about 28% of the total area and about 13% higher than impervious surfaces. Results also suggested that recreation in MC constitutes up to 90% of area followed by transportation and utility. Due to the prevalence of MC in urbanizing regions, the addition of MC to the synthesis of land-cover data can help delineate realistic cover types and area proportions that could inform ecologic/hydrologic models, and allow for accurate prediction of ecological phenomena.

Effects of Land-use/Land-cover and Climate Changes on Water Quantity and Quality in Sub-basins near Major US Cities in the Great Lakes Region

NASA Astrophysics Data System (ADS)

Murphy, L.; Al-Hamdan, M. Z.; Crosson, W. L.; Barik, M.

2017-12-01

Land-cover change over time to urbanized, less permeable surfaces, leads to reduced water infiltration at the location of water input while simultaneously transporting sediments, nutrients and contaminants farther downstream. With an abundance of agricultural fields bordering the greater urban areas of Milwaukee, Detroit, and Chicago, water and nutrient transport is vital to the farming industry, wetlands, and communities that rely on water availability. Two USGS stream gages each located within a sub-basin near each of these Great Lakes Region cities were examined, one with primarily urban land-cover between 1992 and 2011, and one with primarily agriculture land-cover. ArcSWAT, a watershed model and soil and water assessment tool used in extension with ArcGIS, was used to develop hydrologic models that vary the land-covers to simulate surface runoff during a model run period from 2004 to 2008. Model inputs that include a digital elevation model (DEM), Landsat-derived land-use/land-cover (LULC) satellite images from 1992, 2001, and 2011, soil classification, and meteorological data were used to determine the effect of different land-covers on the water runoff, nutrients and sediments. The models were then calibrated and validated to USGS stream gage data measurements over time. Additionally, the watershed model was run based on meteorological data from an IPCC CMIP5 high emissions climate change scenario for 2050. Model outputs from the different LCLU scenarios were statistically evaluated and results showed that water runoff, nutrients and sediments were impacted by LULC change in four out of the six sub-basins. In the 2050 climate scenario, only one out of the six sub-basin's water quantity and quality was affected. These results contribute to the importance of developing hydrologic models as the dependence on the Great Lakes as a freshwater resource competes with the expansion of urbanization leading to the movement of runoff, nutrients, and sediments off the land.

Hyperspectral Sensor Data Capability for Retrieving Complex Urban Land Cover in Comparison with Multispectral Data: Venice City Case Study (Italy)

PubMed Central

Cavalli, Rosa Maria; Fusilli, Lorenzo; Pascucci, Simone; Pignatti, Stefano; Santini, Federico

2008-01-01

This study aims at comparing the capability of different sensors to detect land cover materials within an historical urban center. The main objective is to evaluate the added value of hyperspectral sensors in mapping a complex urban context. In this study we used: (a) the ALI and Hyperion satellite data, (b) the LANDSAT ETM+ satellite data, (c) MIVIS airborne data and (d) the high spatial resolution IKONOS imagery as reference. The Venice city center shows a complex urban land cover and therefore was chosen for testing the spectral and spatial characteristics of different sensors in mapping the urban tissue. For this purpose, an object-oriented approach and different common classification methods were used. Moreover, spectra of the main anthropogenic surfaces (i.e. roofing and paving materials) were collected during the field campaigns conducted on the study area. They were exploited for applying band-depth and sub-pixel analyses to subsets of Hyperion and MIVIS hyperspectral imagery. The results show that satellite data with a 30m spatial resolution (ALI, LANDSAT ETM+ and HYPERION) are able to identify only the main urban land cover materials. PMID:27879879

Mitigating the surface urban heat island: Mechanism study and sensitivity analysis

NASA Astrophysics Data System (ADS)

Meng, Chunlei

2017-08-01

In a surface urban heat island (SUHI), the urban land surface temperature (LST) is usually higher than the temperature of the surrounding rural areas due to human activities and surface characteristics. Because a SUHI has many adverse impacts on urban environment and human health, SUHI mitigation strategies are very important. This paper investigates the mechanism of a SUHI based on the basic physical laws that control the formation of a SUHI; five mitigation strategies are proposed, namely: sprinkling and watering; paving a pervious surface; reducing the anthropogenic heat (AH) release; using a "white roof"; increasing the fractional vegetation cover or leaf area index (LAI). To quantify the effect of these mitigation strategies, 26 sets of experiments are designed and implemented by running the integrated urban land model (IUM). The results of the sensitivity analysis indicate that sprinkling and watering is an effective measure for mitigating a SUHI for an entire day. Decreasing the AH release is also useful for both night- and daytime SUHI mitigation; however, the cooling extent is proportional to the diurnal cycle of AH. Increasing the albedo can reduce the LST in the daytime, especially when the solar radiation is significant; the cooling extent is approximately proportional to the diurnal cycle of the net radiation. Increasing the pervious surface percentage can mitigate the SUHI especially in the daytime. Increasing the fractional vegetation cover can mitigate the SUHI in the daytime but may aggravate the SUHI at night.

Comparison of MODIS Land Surface Temperature and Air Temperature over the Continental USA Meteorological Stations

NASA Technical Reports Server (NTRS)

Zhang, Ping; Bounoua, Lahouari; Imhoff, Marc L.; Wolfe, Robert E.; Thome, Kurtis

2014-01-01

The National Land Cover Database (NLCD) Impervious Surface Area (ISA) and MODIS Land Surface Temperature (LST) are used in a spatial analysis to assess the surface-temperature-based urban heat island's (UHIS) signature on LST amplitude over the continental USA and to make comparisons to local air temperatures. Air-temperature-based UHIs (UHIA), calculated using the Global Historical Climatology Network (GHCN) daily air temperatures, are compared with UHIS for urban areas in different biomes during different seasons. NLCD ISA is used to define urban and rural temperatures and to stratify the sampling for LST and air temperatures. We find that the MODIS LST agrees well with observed air temperature during the nighttime, but tends to overestimate it during the daytime, especially during summer and in nonforested areas. The minimum air temperature analyses show that UHIs in forests have an average UHIA of 1 C during the summer. The UHIS, calculated from nighttime LST, has similar magnitude of 1-2 C. By contrast, the LSTs show a midday summer UHIS of 3-4 C for cities in forests, whereas the average summer UHIA calculated from maximum air temperature is close to 0 C. In addition, the LSTs and air temperatures difference between 2006 and 2011 are in agreement, albeit with different magnitude.

Occurrence and distribution of pesticides and volatile organic compounds in ground water and surface water in Central Arizona Basins, 1996-98, and their relation to land use

USGS Publications Warehouse

Gellenbeck, Dorinda J.; Anning, David W.

2002-01-01

Samples of ground water and surface water from the Sierra Vista subbasin, the Upper Santa Cruz Basin, and the West Salt River Valley were collected and analyzed to determine the occurrence and distribution of pesticides and volatile organic compounds in central Arizona. The study was done during 1996-98 within the Central Arizona Basins study unit of the National Water-Quality Assessment program. This study included 121 wells and 4 surface-water sites in the 3 basins and the analyses of samples from 4 sites along the Santa Cruz River that were part of a separate study. Samples were collected from 121 wells and 3 surface-water sites for pesticide analyses, and samples were collected from 109 wells and 3 surface-water sites for volatile organic compound analyses. Certain pesticides detected in ground water and surface water can be related specifically to agricultural or urban uses; others can be related to multiple land uses. Effects from historical agriculture are made evident by detections of DDE in ground-water and surface-water samples collected in the West Salt River Valley and detections of atrazine and deethylatrazine in the ground water in the Upper Santa Cruz Basin. Effects from present agriculture are evident in the seasonal variability in concentrations of pre-emergent pesticides in surface-water samples from the West Salt River Valley. Several detections of DDE and dieldrin in surface water were higher than established water-quality limits. Effects of urban land use are made evident by detections of volatile organic compounds in ground water and surface water from the West Salt River Valley. Detections of volatile organic compounds in surface water from the Santa Cruz River near Nogales, Arizona, also are indications of the effects of urban land use. One detection of tetrachloroethene in ground water was higher than established water-quality limits. Water reuse is an important conservation technique in the Southwest; however, the reuse of water provides a transport mechanism for pesticides and volatile organic compounds to reach areas that are not normally affected by manmade compounds from specific land-use activities. The most complex mixture of pesticides and volatile organic compounds is in the West Salt River Valley and is the result of water-management practices and the combination of land uses in this basin throughout history.

Regional patterns of pesticide concentrations in surface waters of New York in 1997

USGS Publications Warehouse

Phillips, P.J.; Eckhardt, D.A.; Freehafer, D.A.; Wall, G.R.; Ingleston, H.H.

2002-01-01

The predominant mixtures of pesticides found in New York surface waters consist of five principal components. First, herbicides commonly used on corn (atrazine, metolachlor, alachlor, cyanazine) and a herbicide degradate (deethylatrazine) were positively correlated to a corn-herbicide component, and watersheds with the highest corn-herbicide component scores were those in which large amounts of row crops are grown. Second, two insecticides (diazinon and carbaryl) and one herbicide (prometon) widely used in urban and residential settings were positively correlated to an urban/residential component. Watersheds with the highest urban/residential component scores were those with large amounts of urban and residential land use. A third component was related to two herbicides (EPTC and cyanazine) used on dry beans and corn, the fourth to an herbicide (simazine) and an insecticide (carbaryl) commonly used in orchards and vineyards, and the fifth to an herbicide (DCPA). Results of this study indicate that this approach can be used to: (1) identify common mixtures of pesticides in surface waters, (2) relate these mixtures to land use and pesticide applications, and (3) indicate regions where these mixtures of pesticides are commonly found.

Identifying anthropogenic anomalies in air, surface and groundwater temperatures in Germany.

PubMed

Benz, Susanne A; Bayer, Peter; Blum, Philipp

2017-04-15

Human activity directly influences ambient air, surface and groundwater temperatures. The most prominent phenomenon is the urban heat island effect, which has been investigated particularly in large and densely populated cities. This study explores the anthropogenic impact on the thermal regime not only in selected urban areas, but on a countrywide scale for mean annual temperature datasets in Germany in three different compartments: measured surface air temperature, measured groundwater temperature, and satellite-derived land surface temperature. Taking nighttime lights as an indicator of rural areas, the anthropogenic heat intensity is introduced. It is applicable to each data set and provides the difference between measured local temperature and median rural background temperature. This concept is analogous to the well-established urban heat island intensity, but applicable to each measurement point or pixel of a large, even global, study area. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1km×1km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity, albeit the different compartments are partially influenced through unrelated processes; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities >4K. Overall, surface anthropogenic heat intensities >0K and therefore urban heat islands are observed in communities down to a population of 5000. Copyright © 2017 Elsevier B.V. All rights reserved.

Downscaling of Seasonal Landsat-8 and MODIS Land Surface Temperature (LST) in Kolkata, India

NASA Astrophysics Data System (ADS)

Garg, R. D.; Guha, S.; Mondal, A.; Lakshmi, V.; Kundu, S.

2017-12-01

The quality of life of urban people is affected by urban heat environment. The urban heat studies can be carried out using remotely sensed thermal infrared imagery for retrieving Land Surface Temperature (LST). Currently, high spatial resolution (<200 m) thermal images are limited and their temporal resolution is low (e.g., 17 days of Landsat-8). Coarse spatial resolution (1000 m) and high temporal resolution (daily) thermal images of MODIS (Moderate Resolution Imaging Spectroradiometer) are frequently available. The present study is to downscale spatially coarser resolution of the thermal image to fine resolution thermal image using regression based downscaling technique. This method is based on the relationship between (LST) and vegetation indices (e.g., Normalized Difference Vegetation Index or NDVI) over a heterogeneous landscape. The Kolkata metropolitan city, which experiences a tropical wet-and-dry type of climate has been selected for the study. This study applied different seasonal open source satellite images viz., Landsat-8 and Terra MODIS. The Landsat-8 images are aggregated at 960 m resolution and downscaled into 480, 240 120 and 60 m. Optical and thermal resolution of Landsat-8 and MODIS are 30 m and 60 m; 250 m and 1000 m respectively. The homogeneous land cover areas have shown better accuracy than heterogeneous land cover areas. The downscaling method plays a crucial role while the spatial resolution of thermal band renders it unable for advanced study. Key words: Land Surface Temperature (LST), Downscale, MODIS, Landsat, Kolkata

ESTIMATING AND PROJECTING IMPERVIOUS COVER IN THE SOUTHEASTERN UNITED STATES

EPA Science Inventory

Urban/suburban land constitutes the fastest growing land use class in the Southeastern United States. Predominant development practices increase impervious surface--areas preventing infiltration of water into the underlying soil. Uncontrolled increase of impervious areas (roads,...

ESTIMATING AND PROJECTING IMPERVIOUS COVER IN THE SOUTHEASTERN UNITED STATES

EPA Science Inventory

Urban/suburban land use constitutes the fastest growing land use class in the Southeastern United States. Predominant development practices increase impervious surface--areas preventing infiltration of water into the underlying soil. Uncontrolled increase of impervious areas (ro...

EnviroAtlas - New York, NY - One Meter Resolution Urban Land Cover Data (2008)

EPA Pesticide Factsheets

The New York, NY EnviroAtlas Meter-scale Urban Land Cover (MULC) Data were generated by the University of Vermont Spatial Analysis Laboratory (SAL) under the direction of Jarlath O'Neil-Dunne as part of the United States Forest Service Urban Tree Canopy (UTC) assessment program. Seven classes were mapped using LiDAR and high resolution orthophotography: Tree Canopy, Grass/Shrub, Bare Soil, Water, Buildings, Roads/Railroads, and Other Paved Surfaces. These data were subsequently merged to fit with the EPA classification. The SAL project covered the five boroughs within the NYC city limits. However the EPA study area encompassed that area plus a 1 kilometer buffer. Additional land cover for the buffer area was generated from United States Department of Agriculture (USDA) National Agricultural Imagery Program (NAIP) four band (red, green, blue, and near infrared) aerial photography at 1 m spatial resolution from July, 2011 and LiDAR from 2010. Six land cover classes were mapped: water, impervious surfaces, soil and barren land, trees, grass-herbaceous non-woody vegetation, and agriculture. An accuracy assessment of 600 completely random and 55 stratified random photo interpreted reference points yielded an overall User's fuzzy accuracy of 87 percent. The area mapped is the US Census Bureau's 2010 Urban Statistical Area for New York City plus a 1 km buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAt

Influence of landscape mosaic on streamflow of a peri-urban catchment under Mediterranean climate

NASA Astrophysics Data System (ADS)

Ferreira, Carla; Walsh, Rory; Ferreira, António

2017-04-01

Peri-urban areas tend to be characterized by patchy landscape mosaics of different land-uses. Although the impact of land-use changes on catchment hydrology have been widely investigated, the impact of mixed land-use patterns on the streamflow of peri-urban areas is still poorly understood. This study aims to (i) explore and quantify streamflow delivery from sub-catchments characterized by distinct landscape mosaics; (ii) assess the impact of different urbanization styles on hydrograph properties; and (iii) explore the influence of urbanization type on flow connectivity and stream discharge. The study was carried out in Ribeira dos Covões, a small (6.2km2) peri-urban catchment in central Portugal. The climate is Mediterranean, with a mean annual rainfall of 892mm. Catchment geology comprises sandstone (56%), limestone (41%) and alluvial deposits (3%). Soils developed on sandstone are generally deep (>3m) Fluvisols and Podsols, whereas on limestone the Leptic Cambisols are typically shallow (<0.4m). Forest is the dominant land-use (56%), but urban areas cover an extensive area (40%), whereas agricultural land has declined to a very small area (4%). The urban area comprises contrasting urban styles, notably older discontinuous urban areas with buildings separated by gardens of low population density (<25 inhabitants km-2), and recent well-defined continuous urban cores dominated by apartment blocks and of high population density (9900 inhabitants km-2). The study uses hydrological data recorded over three hydrological years, starting in November 2010, in a monitoring network comprising eight streamflow gauging stations (instrumented with water level recorders) and five rainfall gauges. The gauging stations provide information on the discharge response to rainstorms of the catchment outlet and upstream sub-catchments of different size, urban pattern (in terms of percentage urban land-use and impervious area, distance to the stream network, and storm water management), and lithology (either sandstone or limestone). Annual storm runoff coefficients were lowest (13.7%) in catchments dominated by forest (>80%) and greatest (17.3-17.6%) in the most urbanized sub-catchments (49-53% urban). Impervious area seems to control streamflow particularly during dry periods. Winter runoff (streamflow per unit area) was 2-4 times higher than summer runoff in highly urbanized areas, but was 21-fold higher in winter than in summer in the least urbanized sub-catchment, indicating greater flow connectivity in winter, enhanced by increased soil moisture. Lithology also played an important role on hydrology, with sandstone sub-catchments exhibiting greater annual baseflow index values (23-46%) than found in limestone ones (<5%). For sub-catchments underlain by both lithologies, linear relationships were found between storm runoff coefficients and percentage urban and percentage impervious area, but with greater runoff responses in the sandstone ones. Nevertheless, linear regression lines for both lithologies get close to each other when the extent of urban areas reached about 50%. The proximity of urban areas to the stream network and whether urban storm runoff is directly piped to the stream network were important parameters influencing peak flows and response time. Landscape mosaics that include land-use patches of high soil permeability tend to provide locations of surface water retention and enhanced infiltration, thereby breaking flow connectivity between hillslope urban surfaces and the stream network. This kind of spatial pattern should be considered for urban planning, in order to minimize flood hazards.

Analysis of Upper Air, Ground and Remote Sensing Data for the ATLAS Field Campaign in San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Gonzalez, Jorge E.; Luvall, Jeff; Rickman, Douglas; Comarazamy, Daniel; Picon, Ana J.

2005-01-01

The Atlas San Juan Mission was conducted in February 2004 with the main objectives of observing the Urban Heat Island of San Juan, providing high resolution data of the land use for El Yunque Rain Forest and for calibrating remote sensors. The mission was coordinated with NASA staff members at Marsha& Stennis, Goddard, and Glenn. The Airborne Thermal and Land Applications Sensor (ATLAS) from NASA/Stennis, that operates in the visual and IR bands, was used as the main sensor and was flown over Puerto Rico in a Lear 23 jet plane. To support the data gathering effort by the ATLAS sensor, remote sensing observations and upper air soundings were conducted along with the deployment of a number of ground based weather stations and temperature sensors. This presentation focuses in the analysis of this complementary data for the Atlas San Juan Mission. Upper air data show that during the days of the mission the Caribbean mid and high atmospheres were relatively dry and highly stable reflecting positive surface lifted index, a necessary condition to conduct this suborbital campaign. Surface wind patterns at levels below 850mb were dominated by the easterly trades, while the jet stream at the edge of the troposphere dominated the westerly wind at levels above 500mb. The jet stream remained at high latitudes reducing the possibility of fronts. In consequence, only 8.4 mm of precipitation were reported during the entire mission. Observation of soundings located about 150 km apart reflected minimum variations of the boundary layer across the Island for levels below 850 meters and a uniform atmosphere for higher levels. The weather stations and the temperature sensors were placed at strategic locations to observe variations across the urban and rural landscapes. Time series plot of the stations' data show that heavily urbanized commercial areas have higher air temperatures than urban and suburban residential areas, and much higher temperatures than rural areas. Temperature differences [dT(U-R)] were obtained by subtracting the values of several stations h m a reference urban station, located m the commercial area of San Juan. These time series show that the UHI peaks during the morning between 10:00am and noon to an average of 4.5 C, a temporal pattern not previously observed in similar studies for continental cities. It is also observed a high variability of the UHI with the precipitation patterns even for short events. These results may be a reflection of a large land use density by low level buildings with an apparent absence of significant heat storage effects in the urban areas, and the importance of the surrounding soil and vegetation moisture in controlling the urban tropical climate. The ATLAS data was used to determine albedo and surface temperature patterns on a 10m scale for the study area. These data were used to calibrate the spatial distribution of the surface temperature when using remote sensing images from MODIS (Moderate Resolution Imaging Spectradiometer). Surface temperatures were estimated using the land surface temperature product MODII-L2 distributed by the Land Process Distributed Active Archive Center(LP DAAC). These results show the maximum, minimum and average temperatures in San Juan and in the entire Island at a resolution of 1 km. The information retrieved from MODIS for land surface temperatures reflected similar temporal and spatial variations as the weather stations and ATLAS measurements with a highest absolute offset of about 5 C due to the differences between surface and air temperatures.

Analysis of Upper Air, Ground and Remote Sensing Data For the ATLAS Field Campaign in San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Gonzalez, J. E.; Luvall, J. C.; Rickman, D.; Comarazamy, D. E.; Picon, A.

2004-01-01

The Atlas San Juan Mission was conducted in February 2004 with the main objectives of observing the Urban Heat Island of San Juan, providing high resolution data of the land use for El Yunque Rain Forest and for calibrating remote sensors. The mission was coordinated with NASA staff members at Marshall, Stennis, Goddard, and Glenn. The Airborne Thermal and Land Applications Sensor (ATLAS) from NASA/Stennis, that operates in the visual and IR bands, was used as the main sensor and was flown over Puerto Rico in a Lear 23 jet plane. To support the data gathering effort by the ATLAS sensor, remote sensing observations and upper air soundings were conducted along with the deployment of a number of ground based weather stations and temperature sensors. This presentation focuses in the analysis of this complementary data for the Atlas San Juan Mission. Upper air data show that during the days of the mission the Caribbean mid and high atmospheres were relatively dry and highly stable reflecting positive surface lifted index, a necessary condition to conduct this suborbital campaign. Surface wind patterns at levels below 850mb were dominated by the easterly trades, while the jet stream at the edge of the troposphere dominated the westerly wind at levels above 500mb. The jet stream remained at high latitudes reducing the possibility of fronts. In consequence, only 8.4 mm of precipitation were reported during the entire mission. Observation of soundings located about 150 km apart reflected minimum variations of the boundary layer across the island for levels below 850 meters and a uniform atmosphere for higher levels. The weather stations and the temperature sensors were placed at strategic locations to observe variations across the urban and rural landscapes. Time series plot of the stations' data show that heavily urbanized commercial areas have higher air temperatures than urban and suburban residential areas, and much higher temperatures than rural areas. Temperature differences [dT(U-R)] were obtained by subtracting the values of several stations from a reference urban station, located in the commercial area of San Juan. These time series show that the UHI peaks during the morning between 10:00am and noon to an average of 4.5 C, a temporal pattern not previously observed in similar studies for continental cities. It is also observed a high variability of the UHI with the precipitation patterns even for short events. These results may be a reflection of a large land use density by low level buildings with an apparent absence of significant heat storage effects in the urban areas, and the importance of the surrounding soil and vegetation moisture in controlling the urban tropical climate. The ATLAS data was used to determine albedo and surface temperature patterns on a 10m scale for the study area. These data were used to calibrate the spatial distribution of the surface temperature when using remote sensing images from MODIS (Moderate Resolution Imaging Spectroradiometer). Surface temperatures were estimated using the land surface temperature product MOD11_L2 distributed by the Land Process Distributed Active Archive Center (LP DAAC). These results show the maximum, minimum and average temperatures in San Juan and in the entire Island at a resolution of 1 km. The information retrieved from MODIS for land surface temperatures reflected similar temporal and spatial variations as the weather stations and ATLAS measurements with a highest absolute offset of about 5 C due to the differences between surface and air temperatures.

The scaling of urban surface water abundance and impairment with city size

NASA Astrophysics Data System (ADS)

Steele, M. K.

2018-03-01

Urbanization alters surface water compared to nonurban landscapes, yet little is known regarding how basic aquatic ecosystem characteristics, such as the abundance and impairment of surface water, differ with population size or regional context. This study examined the abundance, scaling, and impairment of surface water by quantifying the stream length, water body area, and impaired stream length for 3520 cities in the United States with populations from 2500 to 18 million. Stream length, water body area, and impaired stream length were quantified using the National Hydrography Dataset and the EPA's 303(d) list. These metrics were scaled with population and city area using single and piecewise power-law models and related to biophysical factors (precipitation, topography) and land cover. Results show that abundance of stream length and water body area in cities actually increases with city area; however, the per person abundance decreases with population size. Relative to population, impaired stream length did not increase until city populations were > 25,000 people, then scaled linearly with population. Some variation in abundance and impairment was explained by biophysical context and land cover. Development intensity correlated with stream density and impairment; however, those relationships depended on the orientation of the land covers. When high intensity development occupied the local elevation highs (+ 15 m) and undeveloped land the elevation lows, the percentage of impaired streams was less than the opposite land cover orientation (- 15 m) or very flat land. These results show that surface water abundance and impairment across contiguous US cities are influenced by city size and by biophysical setting interacting with land cover intensity.

Effects of urban land-use change in East China on the East Asian summer monsoon based on the CAM5.1 model

NASA Astrophysics Data System (ADS)

Ma, Hongyun; Jiang, Zhihong; Song, Jie; Dai, Aiguo; Yang, Xiuqun; Huo, Fei

2016-05-01

The effects of urban land-use change in East China on the East Asian summer monsoon (EASM) are investigated using a Community Atmosphere Model Version 5.1. The results show that the urban land-use change in East China causes spatially-varying changes in surface net radiation and heat fluxes, atmospheric circulation, and water budgets. It results in significant surface warming (cooling) and precipitation decrease (increase) in a large region north (south) of 30°N. Urban expansion agglomerated in (29°-41°N, 110°-122°E) alters the surface energy budget and warms the surface, resulting in strengthened southwesterly airflow south of 25°N and increased convergence below the mid-troposphere between 20° and 30°N. A concomitant northward downdraft associated with the increased convection generates an anomalous high pressure north of 30°N. Meanwhile, the downdraft not only produces adiabatic warming but also inhibits the dynamic condition for precipitation formation. The anomalous high pressure formed in North China prevents the southwesterly airflow from advancing northward, leading to increase the convergence and precipitation in South China. These changes reduce the meridional temperature gradient in the mid-lower troposphere and weaken the westerly airflow near 30°N. In addition, horizontal transport of vorticity north of 35°N weakens significantly, which leads to an anomalous barotropic structure of anticyclonic there. As a result, the anomalous anticyclonic circulation and descent north of 30°N are strengthened. At the same time, the anomalous cyclonic circulation and ascent south of 30°N are enhanced. These process induced by the thermal state changes due to urbanization weakens the EASM.

Linking land use changes to surface water quality variability in Lake Victoria: some insights from remote sensing

NASA Astrophysics Data System (ADS)

Mugo, R. M.; Limaye, A. S.; Nyaga, J. W.; Farah, H.; Wahome, A.; Flores, A.

2016-12-01

The water quality of inland lakes is largely influenced by land use and land cover changes within the lake's catchment. In Africa, some of the major land use changes are driven by a number of factors, which include urbanization, intensification of agricultural practices, unsustainable farm management practices, deforestation, land fragmentation and degradation. Often, the impacts of these factors are observable on changes in the land cover, and eventually in the hydrological systems. When the natural vegetation cover is reduced or changed, the surface water flow patterns, water and nutrient retention capacities are also changed. This can lead to high nutrient inputs into lakes, leading to eutrophication, siltation and infestation of floating aquatic vegetation. To assess the relationship between land use and land cover changes in part of the Lake Victoria Basin, a series of land cover maps were derived from Landsat imagery. Changes in land cover were identified through change maps and statistics. Further, the surface water chlorophyll-a concentration and turbidity were derived from MODIS-Aqua data for Lake Victoria. Chlrophyll-a and turbidity are good proxy indicators of nutrient inputs and siltation respectively. The trends in chlorophyll-a and turbidity concentrations were analyzed and compared to the land cover changes over time. Certain land cover changes related to agriculture and urban development were clearly identifiable. While these changes might not be solely responsible for variability in chlrophyll-a and turbidity concentrations in the lake, they are potentially contributing factors to this problem. This work illustrates the importance of addressing watershed degradation while seeking to solve water quality related problems.

Subpixel urban land cover estimation: comparing cubist, random forests, and support vector regression

Treesearch

Jeffrey T. Walton

2008-01-01

Three machine learning subpixel estimation methods (Cubist, Random Forests, and support vector regression) were applied to estimate urban cover. Urban forest canopy cover and impervious surface cover were estimated from Landsat-7 ETM+ imagery using a higher resolution cover map resampled to 30 m as training and reference data. Three different band combinations (...

Urban Heat Island in the city of Bari (Italy) ant its relationship with morphological features

NASA Astrophysics Data System (ADS)

Ceppi, C.; Balena, P.; Loconte, P.; Mancini, F.

2012-04-01

The investigation of an Urban Heat Island (UHI) and its relationship with the wide range of factors able to explain its behavior is a very difficult task: the main trouble is represented by the spatial variability of the urban temperature due to the extreme heterogeneousness of the urban coverage and morphological features. In literature it is known that the local surface temperatures are influenced by the changing characteristics in urban surface and modification of land surface processes affecting the surface energy balance and the shape of boundary layer. The whole processes could lead to distinct urban climates. This work is mainly focused on the mechanisms which are actually connecting the urban morphology with the surface temperature as derived by satellite data provided from the ASTER sensor. Urban morphology could be described by several factors depending on the selected scale of analysis. At the macroscale the UHI is more related to the land-use, environmental context and boundary conditions. At the microscale the surface characteristics, urban density, ratio between green and built areas and, construction and built typology are more involved in addition to the composite indicators such as the Sky View factor and the elevation of the built texture. The case study of the city of Bari is faced. It is a medium sized city in the southern Italy, characterized by the presence of a pervasive waterfront and presence of "lame", a natural erosive furrows shallow that are typical of the Apulia country side. Such ephemeral streams convey the stormwater from the plateau of the hilly Murgia areas to the sea. Moreover, the urban complexity of the city exacerbates the spatial variability of the phenomenon. The first step aim at the investigating of the relationship between the thermal behavior and the above mentioned factors by the construction of a set of homogeneous morphological units. The classification is built both in the urban and rural zone. The second step focuses on the development of a spatial statistical analysis based on qualitative and quantitative indicators able to link the classes of urban morphology with the satellite-based surface temperature. The relationships highlighted by such a spatial analysis can be used to model the urban climate and, consequently, develop a new kind of planning more addressed towards the mitigation of the UHI phenomenon.

Linking Land Use Changes to Surface Water Quality Variability in Lake Victoria: Some Insights From Remote Sensing (GC41B-1101)

NASA Technical Reports Server (NTRS)

Limaye, Ashutosh; Mugo, Robinson; Wanjohi, James; Farah, Hussein; Wahome, Anastasia; Flores, Africa; Irwin, Dan

2016-01-01

Various land use changes driven by urbanization, conversion of grasslands and woodlands into farmlands, intensification of agricultural practices, deforestation, land fragmentation and degradation are taking place in Africa. In Kenya, agriculture is the main driver of land use conversions. The impacts of these land use changes are observable in land cover maps, and eventually in the hydrological systems. Reduction or change of natural vegetation cover types increases the speed of surface runoff and reduces water and nutrient retention capacities. This can lead to high nutrient inputs into lakes, resulting in eutrophication, siltation and infestation of floating aquatic vegetation. To assess if changes in land use could be contributing to increased phytoplankton blooms and sediment loads into Lake Victoria, we analyzed land use land cover data from Landsat, as well as surface chlorophyll-a and total suspended matter from MODIS-Aqua sensor.

ESTIMATING AND PROJECTING IMPERVIOUS COVER IN THE SOUTHEASTERN UNITED STATES

EPA Science Inventory

Urban/suburban land use is the most rapidly growing land use class. Along with increased development inevitably comes increased impervious surface--areas preventing infiltration of water into the underlying soil. The extensive hydrological alteration of watersheds associated wi...

Anthropogenic land uses elevate metal levels in stream water in an urbanizing watershed.

PubMed

Yu, Shen; Wu, Qian; Li, Qingliang; Gao, Jinbo; Lin, Qiaoying; Ma, Jun; Xu, Qiufang; Wu, Shengchun

2014-08-01

Land use/cover change is a dominant factor affecting surface water quality in rapidly developing areas of Asia. In this study we examined relationships between land use and instream metal loadings in a rapidly developing mixed land use watershed in southeastern China. Five developing subwatersheds and one forested reference site (head water) were instrumented with timing- and rainfall-triggered autosampler and instream loadings of anthropogenic metals (Cu, Zn, Pb, Cr, Cd, and Mn) were monitored from March 2012 to December 2013. Farm land and urban land were positively, and forest and green land were negatively associated with metal loadings (except Cr) in stream water. All developing sites had higher loadings than the reference head water site. Assessed by Chinese surface water quality standard (GB3830-2002), instream loadings of Cu and Zn occasionally exceeded the Class I thresholds at monitoring points within farmland dominated subwatersheds while Mn loadings were greater than the limit for drinking water sources at all monitoring points. Farm land use highly and positively contributed to statistical models of instream loadings of Cu, Zn, Cd, and Mn while urban land use was the dominant contributor to models of Pb and Cd loadings. Rainfall played a crucial role in metal loadings in stream water as a direct source (there were significant levels of Cu and Zn in rain water) and as a driver of watershed processes (loadings were higher in wet years and seasons). Urbanization effects on metal loadings in this watershed are likely to change rapidly with development in future years. Further monitoring to characterize these changes is clearly warranted and should help to develop plans to avoid conflicts between economic development and water quality degradation in this watershed and in watersheds throughout rapidly developing areas of Asia. Copyright © 2014 Elsevier B.V. All rights reserved.

Numerical simulation of the impact of reforestation on winter meteorology and environment in a semi-arid urban valley, Northwestern China.

PubMed

Yu, Ye; He, Jianjun; Zhao, Suping; Liu, Na; Chen, Jinbei; Mao, Hongjun; Wu, Lin

2016-11-01

Since 1999 Chinese government has made great effort to reforest the south and north mountains surrounding urban Lanzhou - a city located in a river valley, Northwestern China. Until 2009 obvious land use change occurred, with 69.2% of the reforested area been changed from grasslands, croplands, barren or sparsely vegetated land to closed shrublands and 20.6% from closed shrublands, grasslands, and croplands to forests. Reforestation changes land-surface properties, with possible impact on the evolution of atmospheric variables. To understand to what extent the local meteorology and environment could be affected by reforestation in winter, and through what processes, two sets of simulations were conducted using the Weather Research and Forecasting model (WRF) and the FLEXible PARTicle (FLEXPART) dispersion model for a control case with high-resolution remotely sensed land cover data for 2009 and a scenario assuming no reforestation since 1999. Results suggested that the changes in albedo, surface exchange coefficient and surface soil heat conductivity related to reforestation led to the changes in surface net radiation and surface energy partitioning, which in turn affected the meteorological fields and enhanced the mountain-valley wind circulation. Replacement of shrublands and grassland with forest in the south mountain through reforestation play a dominant role in the enhancement of mountain-valley wind circulation. Reforestation increased the amount of air exchanged between the valley and the outside during the day, with the largest hourly increase of 10% on calm weather days and a monthly mean hourly increase of 2% for the study period (Dec. 2009). Reforestation affected the spatial distribution of pollutants and slightly improved the urban air quality, especially in the eastern valley. Results from this study provide useful information for future urban air quality management and reforestation plan, and some experience for cities with similar situations in the world. Copyright © 2016 Elsevier B.V. All rights reserved.

Environmental Setting and the Effects of Natural and Human-Related Factors on Water Quality and Aquatic Biota, Oahu, Hawaii

USGS Publications Warehouse

Oki, Delwyn S.; Brasher, Anne M.D.

2003-01-01

The island of Oahu is the third largest island of the State of Hawaii, and is formed by the eroded remnants of the Waianae and Koolau shield volcanoes. The landscape of Oahu ranges from a broad coastal plain to steep interior mountains. Rainfall is greatest in the mountainous interior parts of the island, and lowest near the southwestern coastal areas. The structure and form of the two volcanoes in conjunction with processes that have modified the original surfaces of the volcanoes control the hydrologic setting. The rift zones of the volcanoes contain dikes that tend to impede the flow of ground water, leading to high ground-water levels in the dike-impounded ground-water system. In the windward (northeastern) part of the island, dike-impounded ground-water levels may reach the land surface in stream valleys, resulting in ground-water discharge to streams. Where dikes are not present, the volcanic rocks are highly permeable, and a lens of freshwater overlies a brackish-water transition zone separating the freshwater from saltwater. Ground water discharges to coastal springs and streams where the water table in the freshwater-lens system intersects the land surface. The Waianae and Koolau Ranges have been deeply dissected by numerous streams. Streams originate in the mountainous interior areas and terminate at the coast. Some streams flow perennially throughout their entire course, others flow perennially over parts of their course, and the remaining streams flow during only parts of the year throughout their entire course. Hawaiian streams have relatively few native species compared to continental streams. Widespread diverse orders of insects are absent from the native biota, and there are only five native fish, two native shrimp, and a few native snails. The native fish and crustaceans of Hawaii's freshwater systems are all amphidromous (adult lives are spent in streams, and larval periods as marine or estuarine zooplankton). During the 20th century, land-use patterns on Oahu reflected increases in population and decreases in large-scale agricultural operations over time. The last two remaining sugarcane plantations on Oahu closed in the mid-1990's, and much of the land that once was used for sugarcane now is urbanized or used for diversified agriculture. Although two large pineapple plantations continue to operate in central Oahu, some of the land previously used for pineapple cultivation has been urbanized. Natural and human-related factors control surface- and ground-water quality and the distribution and abundance of aquatic biota on Oahu. Natural factors that may affect water quality include geology, soils, vegetation, rainfall, ocean-water quality, and air quality. Human-related factors associated with urban and agricultural land uses also may affect water quality. Ground-water withdrawals may cause saltwater intrusion. Pesticides and fertilizers that were used in agricultural or urban areas have been detected in surface and ground water on Oahu. In addition, other organic compounds associated with urban uses of chemicals have been detected in surface and ground water on Oahu. The effects of urbanization and agricultural practices on instream and riparian areas in conjunction with a proliferation of nonnative fish and crustaceans have resulted in a paucity of native freshwater macrofauna on Oahu. A variety of pesticides, nutrients, and metals are associated with urban and agricultural land uses, and these constituents can affect the fish and invertebrates that live in the streams.

Remote Sensing of Urban Land Cover/Land Use Change, Surface Thermal Responses, and Potential Meteorological and Climate Change Impacts

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Jedlovec, Gary; Meyer, Paul

2011-01-01

City growth influences the development of the urban heat island (UHI), but the effect that local meteorology has on the UHI is less well known. This paper presents some preliminary findings from a study that uses multitemporal Landsat TM and ASTER data to evaluate land cover/land use change (LULCC) over the NASA Marshall Space Flight Center (MFSC) and its Huntsville, AL metropolitan area. Landsat NLCD data for 1992 and 2001 have been used to evaluate LULCC for MSFC and the surrounding urban area. Land surface temperature (LST) and emissivity derived from NLCD data have also been analyzed to assess changes in these parameters in relation to LULCC. Additionally, LULCC, LST, and emissivity have been identified from ASTER data from 2001 and 2011 to provide a comparison with the 2001 NLCD and as a measure of current conditions within the study area. As anticipated, the multi-temporal NLCD and ASTER data show that significant changes have occurred in land covers, LST, and emissivity within and around MSFC. The patterns and arrangement of these changes, however, is significant because the juxtaposition of urban land covers within and outside of MSFC provides insight on what impacts at a local to regional scale, the inter-linkage of these changes potentially have on meteorology. To further analyze these interactions between LULCC, LST, and emissivity with the lower atmosphere, a network of eleven weather stations has been established across the MSFC property. These weather stations provide data at a 10 minute interval, and these data are uplinked for use by MSFC facilities operations and the National Weather Service. The weather data are also integrated within a larger network of meteorological stations across north Alabama. Given that the MSFC weather stations will operate for an extended period of time, they can be used to evaluate how the building of new structures, and changes in roadways, and green spaces as identified in the MSFC master plan for the future, will potentially affect land cover LSTs across the Center. Moreover, the weather stations will also provide baseline data for developing a better understanding of how localized weather factors, such as extreme rainfall and heat events, affect micrometeorology. These data can also be used to model the interrelationships between LSTs and meteorology on a longer term basis to help evaluate how changes in these parameters can be quantified from satellite data collected in the future. In turn, the overall integration of multi-temporal meteorological information with LULCC, and LST data for MSFC proper and the surrounding Huntsville urbanized area can provide a perspective on how urban land surface types affect the meteorology in the boundary layer and ultimately, the UHI. Additionally, data such as this can be used as a foundation for modeling how climate change will potentially impact local and regional meteorology and conversely, how urban LULCC can or will influence changes on climate over the north Alabama area.

Assessing climate impacts of planning policies-An estimation for the urban region of Leipzig (Germany)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwarz, Nina, E-mail: nina.schwarz@ufz.de; Bauer, Annette, E-mail: annette.bauer@ufz.de; Haase, Dagmar, E-mail: dagmar.haase@ufz.d

2011-03-15

Local climate regulation by urban green areas is an important urban ecosystem service, as it reduces the extent of the urban heat island and therefore enhances quality of life. Local and regional planning policies can control land use changes in an urban region, which in turn alter local climate regulation. Thus, this paper describes a method for estimating the impacts of current land uses as well as local and regional planning policies on local climate regulation, using evapotranspiration and land surface emissivity as indicators. This method can be used by practitioners to evaluate their policies. An application of this methodmore » is demonstrated for the case study Leipzig (Germany). Results for six selected planning policies in Leipzig indicate their distinct impacts on climate regulation and especially the role of their spatial extent. The proposed method was found to easily produce a qualitative assessment of impacts of planning policies on climate regulation.« less

Urbanization-induced urban heat island and aerosol effects on climate extremes in the Yangtze River Delta region of China

NASA Astrophysics Data System (ADS)

Zhong, Shi; Qian, Yun; Zhao, Chun; Leung, Ruby; Wang, Hailong; Yang, Ben; Fan, Jiwen; Yan, Huiping; Yang, Xiu-Qun; Liu, Dongqing

2017-04-01

The WRF-Chem model coupled with a single-layer urban canopy model (UCM) is integrated for 5 years at convection-permitting scale to investigate the individual and combined impacts of urbanization-induced changes in land cover and pollutant emissions on regional climate in the Yangtze River Delta (YRD) region in eastern China. Simulations with the urbanization effects reasonably reproduced the observed features of temperature and precipitation in the YRD region. Urbanization over the YRD induces an urban heat island (UHI) effect, which increases the surface temperature by 0.53 °C in summer and increases the annual heat wave days at a rate of 3.7 d yr-1 in the major megacities in the YRD, accompanied by intensified heat stress. In winter, the near-surface air temperature increases by approximately 0.7 °C over commercial areas in the cities but decreases in the surrounding areas. Radiative effects of aerosols tend to cool the surface air by reducing net shortwave radiation at the surface. Compared to the more localized UHI effect, aerosol effects on solar radiation and temperature influence a much larger area, especially downwind of the city cluster in the YRD. Results also show that the UHI increases the frequency of extreme summer precipitation by strengthening the convergence and updrafts over urbanized areas in the afternoon, which favor the development of deep convection. In contrast, the radiative forcing of aerosols results in a surface cooling and upper-atmospheric heating, which enhances atmospheric stability and suppresses convection. The combined effects of the UHI and aerosols on precipitation depend on synoptic conditions. Two rainfall events under two typical but different synoptic weather patterns are further analyzed. It is shown that the impact of urban land cover and aerosols on precipitation is not only determined by their influence on local convergence but also modulated by large-scale weather systems. For the case with a strong synoptic forcing associated with stronger winds and larger spatial convergence, the UHI and aerosol effects are relatively weak. When the synoptic forcing is weak, however, the UHI and aerosol effects on local convergence dominate. This suggests that synoptic forcing plays a significant role in modulating the urbanization-induced land-cover and aerosol effects on individual rainfall event. Hence precipitation changes due to urbanization effects may offset each other under different synoptic conditions, resulting in little changes in mean precipitation at longer timescales.

Urbanization-induced urban heat island and aerosol effects on climate extremes in the Yangtze River Delta region of China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong, Shi; Qian, Yun; Zhao, Chun

The WRF-Chem model coupled with a single-layer urban canopy model (UCM) is integrated for 5 years at convection-permitting scale to investigate the individual and combined impacts of urbanization-induced changes in land cover and pollutant emissions on regional climate in the Yangtze River Delta (YRD) region in eastern China. Simulations with the urbanization effects reasonably reproduced the observed features of temperature and precipitation in the YRD region. Urbanization over the YRD induces an urban heat island (UHI) effect, which increases the surface temperature by 0.53 °C in summer and increases the annual heat wave days at a rate of 3.7 d yr −1 in themore » major megacities in the YRD, accompanied by intensified heat stress. In winter, the near-surface air temperature increases by approximately 0.7 °C over commercial areas in the cities but decreases in the surrounding areas. Radiative effects of aerosols tend to cool the surface air by reducing net shortwave radiation at the surface. Compared to the more localized UHI effect, aerosol effects on solar radiation and temperature influence a much larger area, especially downwind of the city cluster in the YRD. Results also show that the UHI increases the frequency of extreme summer precipitation by strengthening the convergence and updrafts over urbanized areas in the afternoon, which favor the development of deep convection. In contrast, the radiative forcing of aerosols results in a surface cooling and upper-atmospheric heating, which enhances atmospheric stability and suppresses convection. The combined effects of the UHI and aerosols on precipitation depend on synoptic conditions. Two rainfall events under two typical but different synoptic weather patterns are further analyzed. It is shown that the impact of urban land cover and aerosols on precipitation is not only determined by their influence on local convergence but also modulated by large-scale weather systems. For the case with a strong synoptic forcing associated with stronger winds and larger spatial convergence, the UHI and aerosol effects are relatively weak. When the synoptic forcing is weak, however, the UHI and aerosol effects on local convergence dominate. This suggests that synoptic forcing plays a significant role in modulating the urbanization-induced land-cover and aerosol effects on individual rainfall event. Hence precipitation changes due to urbanization effects may offset each other under different synoptic conditions, resulting in little changes in mean precipitation at longer timescales.« less

Urbanization-induced urban heat island and aerosol effects on climate extremes in the Yangtze River Delta region of China

DOE PAGES

Zhong, Shi; Qian, Yun; Zhao, Chun; ...

2017-04-27

The WRF-Chem model coupled with a single-layer urban canopy model (UCM) is integrated for 5 years at convection-permitting scale to investigate the individual and combined impacts of urbanization-induced changes in land cover and pollutant emissions on regional climate in the Yangtze River Delta (YRD) region in eastern China. Simulations with the urbanization effects reasonably reproduced the observed features of temperature and precipitation in the YRD region. Urbanization over the YRD induces an urban heat island (UHI) effect, which increases the surface temperature by 0.53 °C in summer and increases the annual heat wave days at a rate of 3.7 d yr −1 in themore » major megacities in the YRD, accompanied by intensified heat stress. In winter, the near-surface air temperature increases by approximately 0.7 °C over commercial areas in the cities but decreases in the surrounding areas. Radiative effects of aerosols tend to cool the surface air by reducing net shortwave radiation at the surface. Compared to the more localized UHI effect, aerosol effects on solar radiation and temperature influence a much larger area, especially downwind of the city cluster in the YRD. Results also show that the UHI increases the frequency of extreme summer precipitation by strengthening the convergence and updrafts over urbanized areas in the afternoon, which favor the development of deep convection. In contrast, the radiative forcing of aerosols results in a surface cooling and upper-atmospheric heating, which enhances atmospheric stability and suppresses convection. The combined effects of the UHI and aerosols on precipitation depend on synoptic conditions. Two rainfall events under two typical but different synoptic weather patterns are further analyzed. It is shown that the impact of urban land cover and aerosols on precipitation is not only determined by their influence on local convergence but also modulated by large-scale weather systems. For the case with a strong synoptic forcing associated with stronger winds and larger spatial convergence, the UHI and aerosol effects are relatively weak. When the synoptic forcing is weak, however, the UHI and aerosol effects on local convergence dominate. This suggests that synoptic forcing plays a significant role in modulating the urbanization-induced land-cover and aerosol effects on individual rainfall event. Hence precipitation changes due to urbanization effects may offset each other under different synoptic conditions, resulting in little changes in mean precipitation at longer timescales.« less

Human-Induced Climate Variations Linked to Urbanization: From Observations to Modeling

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Jin, Menglin

2004-01-01

The goal of this session is to bring together scientists from interdisciplinary backgrounds to discuss the data, scientific approaches and recent results focusing on the impact of urbanization on the climate. The discussion will highlight current observational and modeling capabilities being employed for investigating the urban environment and its linkage to the change in the Earth's climate system. The goal of the session is to identify our current stand and the future direction on the topic. Urbanization is one of the extreme cases of land use change. Most of population of the world has moved to urban areas. By 1995, more than 70% of population of North America and Europe were living in cities. By 2025, the United Nations estimates that 60% of the worlds population will live in cities. Although currently only 1.2% of the land is urban, better understanding of how the atmosphere-ocean-land-biosphere components interact as a coupled system and the influence of human activities on this system is critical. Our understanding of urbanization effect is incomplete, partly because human activities induce new changes on climate in addition to the original natural variations, and partly because previously few data available for study urban effect globally. Urban construction changes surface roughness, albedo, heat capacity and vegetation coverage. Traffic and industry increase atmospheric aerosol. It is suggested that urbanization may modify rainfall processes through aerosol-cloud interactions or dynamic feedbacks. Because urbanization effect on climate is determined by many factors including land cover, the city's microscale features, population density, and human lifestyle patterns, it is necessary to study urban areas over globe.

Potential impacts of urban land expansion on Asian airborne pollutant outflows

NASA Astrophysics Data System (ADS)

Tao, Wei; Liu, Junfeng; Ban-Weiss, George A.; Zhang, Lin; Zhang, Jiachen; Yi, Kan; Tao, Shu

2017-07-01

Eastern part of China (EPC) has experienced rapid urbanization during the past few decades. Here we investigate the impacts of urban land expansion over EPC on the export of Asian pollutants to the western Pacific during January, April, July, and October of 2009 using the Weather Research and Forecasting model coupled to Chemistry (WRF/Chem) and a single-layer urban canopy scheme. Over urbanizing areas, increases in the urban land fraction result in a linearly enhanced uplift of surface primary pollutants to higher altitudes. We further examine how this local effect would change outflows of Asian pollutants to the western Pacific using the tagged black carbon (BC) and carbon monoxide (CO) tracers emitted from EPC (denoted by BCt and COt, respectively). Overall, a 0.1 increase in the fraction of land area that is urban over EPC would linearly (R2 = 0.70-0.96) increase the mean tropospheric eastward export of BCt and COt across meridional planes (i.e., 135°E and 150°E) by 4-40% and 1-6% in different months, respectively. The relative perturbation in exporting efficiency generally maximizes during July while minimizes during April. The urbanization-export relationship is largely driven by the elevation effect and is also impacted by urbanization-forced changes in zonal winds. The spatial pattern of the response of BCt over the downwind Pacific differs from that of COt mainly due to aerosol-cloud interactions. Our findings demonstrate that extensive urban land expansion could substantially impact climate and air quality from a local scale to a regional scale, especially for shorter-lived air pollutants such as BC and other aerosols.

Urban Boundary Extraction and Urban Sprawl Measurement Using High-Resolution Remote Sensing Images: a Case Study of China's Provincial

NASA Astrophysics Data System (ADS)

Wang, H.; Ning, X.; Zhang, H.; Liu, Y.; Yu, F.

2018-04-01

Urban boundary is an important indicator for urban sprawl analysis. However, methods of urban boundary extraction were inconsistent, and construction land or urban impervious surfaces was usually used to represent urban areas with coarse-resolution images, resulting in lower precision and incomparable urban boundary products. To solve above problems, a semi-automatic method of urban boundary extraction was proposed by using high-resolution image and geographic information data. Urban landscape and form characteristics, geographical knowledge were combined to generate a series of standardized rules for urban boundary extraction. Urban boundaries of China's 31 provincial capitals in year 2000, 2005, 2010 and 2015 were extracted with above-mentioned method. Compared with other two open urban boundary products, accuracy of urban boundary in this study was the highest. Urban boundary, together with other thematic data, were integrated to measure and analyse urban sprawl. Results showed that China's provincial capitals had undergone a rapid urbanization from year 2000 to 2015, with the area change from 6520 square kilometres to 12398 square kilometres. Urban area of provincial capital had a remarkable region difference and a high degree of concentration. Urban land became more intensive in general. Urban sprawl rate showed inharmonious with population growth rate. About sixty percent of the new urban areas came from cultivated land. The paper provided a consistent method of urban boundary extraction and urban sprawl measurement using high-resolution remote sensing images. The result of urban sprawl of China's provincial capital provided valuable urbanization information for government and public.

Assessment of Urban Infrastructure Impact on New York City Neighborhoods Thermal Variations

NASA Astrophysics Data System (ADS)

Nazari, R.; Ghandehari, M.; Karimi, M.; Vant-hull, B.; Khanbilvardi, R.

2013-12-01

New York City (NYC) is a highly urbanized city with most of the population living in tall buildings. Despite technological improvements and stricter regulations, cities still show increasing signs of environmental stress such as traffic congestion, noise and air quality degradation. Rethinking the current models of city planning could enable to limit these detrimental effects of urbanization. In addition, the built environment creates a new climatic regime which needs a better understanding. Building density, height and emission has a major impact on local temperature and other air quality indicators. Studies have shown that during extreme weather conditions and heat waves the mortality rate in urban areas increases. Cities are comprised of a wide variety of urban settings and various neighborhoods have different physical responses to meteorological events, so it is expected that the temperature and heat stress across a given city to fluctuate sharply. Therefore, this research has focused on neighborhood-scale field campaigns to downscale temperature and air quality predictions from city to neighborhood scale in NYC. In order to assess the temperature variability within the city at street level, during the hottest part of the day, this project used eight mobile units bearing temperature and relative humidity sensors, as well as ten weather stations mounted on light poles in various NYC neighborhoods. This study also looks at fine scale structures in the urban heat island of Manhattan at street level through an infrared camera with the spectral range of 7.5-13 μm in order to relate heat and emissions from building surfaces to land surface characteristics such as building density, vegetation coverage, proximity to water, and albedo. LandSat TM5 images were used (with 30 m resolution) for land surface classification. During the summer and early fall of 2011, 2012 and 2013 extensive field campaigns were performed, the results of which show some persistent patterns that could be related to surface characteristics. This work is a collaboration between the health component of the Consortium for Climate Risk in the Urban Northeast (CCRUN), funded by NOAA Regional Integrated Science Assessment (RISA), and New York University Center for Urban Science and Progress (CUSP).

High-resolution surface connectivity measurements and runoff dynamics in five urban watersheds in Knoxville, TN

NASA Astrophysics Data System (ADS)

Epps, T.

2015-12-01

Impervious surfaces and stormwater drainage networks transmit rainfall quickly to urban stream systems with greater frequency, volume, energy, and pollutant loadings than in predevelopment conditions. This has a well-established negative impact on stream ecology, channel morphology, and water quality. Green infrastructure retrofits for urban drainage systems promote more natural hydrologic pathways by disconnecting concentrated flows. However, they are expensive due to high land costs and physical constraints. If a systematic strategy for siting green infrastructure is sought to restore natural flows throughout an urban catchment, greater knowledge of the drainage patterns and areas contributing frequent surface runoff is necessary. Five diverse urban watersheds in Knoxville, TN, were assessed using high-resolution topography, land cover, and artificial drainage network data to identify how surface connectivity differs among watersheds and contributes to altered flow regimes. Rainfall-runoff patterns were determined from continuous rainfall and streamflow monitoring over the previous ten years. Fine-scale flowpath connectivity of impervious surfaces was measured by both a binary approach and by a method incorporating runoff potential by saturation excess. The effect of the spatial distribution of connected surfaces was investigated by incorporating several distance-weighting schema along established urban drainage flowpaths. Statistical relationships between runoff generation and connectivity were measured to determine the ability of these different measures of connectivity to predict runoff thresholds, frequency, volumes, and peak flows. Initial results suggest that rapid assessment of connected surficial flowpaths can be used to identify known green infrastructure assets and highly connected impervious areas and that the differences in connectivity measured between watersheds reflects differing runoff patterns observed in monitored data.

Cooling effect of rivers on metropolitan Taipei using remote sensing.

PubMed

Chen, Yen-Chang; Tan, Chih-Hung; Wei, Chiang; Su, Zi-Wen

2014-01-23

This study applied remote sensing technology to analyze how rivers in the urban environment affect the surface temperature of their ambient areas. While surface meteorological stations can supply accurate data points in the city, remote sensing can provide such data in a two-dimensional (2-D) manner. The goal of this paper is to apply the remote sensing technique to further our understanding of the relationship between the surface temperature and rivers in urban areas. The 2-D surface temperature data was retrieved from Landsat-7 thermal infrared images, while data collected by Formosat-2 was used to categorize the land uses in the urban area. The land surface temperature distribution is simulated by a sigmoid function with nonlinear regression analysis. Combining the aforementioned data, the range of effect on the surface temperature from rivers can be derived. With the remote sensing data collected for the Taipei Metropolitan area, factors affecting the surface temperature were explored. It indicated that the effect on the developed area was less significant than on the ambient nature zone; moreover, the size of the buffer zone between the river and city, such as the wetlands or flood plain, was found to correlate with the affected distance of the river surface temperature.

Cooling Effect of Rivers on Metropolitan Taipei Using Remote Sensing

PubMed Central

Chen, Yen-Chang; Tan, Chih-Hung; Wei, Chiang; Su, Zi-Wen

2014-01-01

This study applied remote sensing technology to analyze how rivers in the urban environment affect the surface temperature of their ambient areas. While surface meteorological stations can supply accurate data points in the city, remote sensing can provide such data in a two-dimensional (2-D) manner. The goal of this paper is to apply the remote sensing technique to further our understanding of the relationship between the surface temperature and rivers in urban areas. The 2-D surface temperature data was retrieved from Landsat-7 thermal infrared images, while data collected by Formosat-2 was used to categorize the land uses in the urban area. The land surface temperature distribution is simulated by a sigmoid function with nonlinear regression analysis. Combining the aforementioned data, the range of effect on the surface temperature from rivers can be derived. With the remote sensing data collected for the Taipei Metropolitan area, factors affecting the surface temperature were explored. It indicated that the effect on the developed area was less significant than on the ambient nature zone; moreover, the size of the buffer zone between the river and city, such as the wetlands or flood plain, was found to correlate with the affected distance of the river surface temperature. PMID:24464232

Impact of Extensive Urbanization on Summertime Rainfall in the Beijing Region and the Role of Local Precipitation Recycling

NASA Astrophysics Data System (ADS)

Wang, Jun; Feng, Jinming; Yan, Zhongwei

2018-04-01

In this study, we conducted nested high-resolution simulations using the Weather Research and Forecasting model coupled with a single-layer urban canopy model to investigate the impact of extensive urbanization on regional precipitation over the Beijing-Tianjin-Hebei region in China. The results showed that extensive urbanization decreased precipitation considerably over and downwind of Beijing city. The prevalence of impermeable urban land inhibits local evaporation that feeds moisture into the overlying atmosphere, decreasing relative humidity and atmospheric instability. The dynamic precipitation recycling model was employed to estimate the precipitation that originates from local surface evaporation and large-scale advection of moisture. Results showed that about 11% of the urbanization-induced decrease in total precipitation over the Greater Beijing Region and its surroundings was contributed by the decrease in local recycled precipitation, while the other part (89%) was due to decreasing large-scale advected precipitation. Results suggest that the low evaporation from urban land surfaces not only reduces the supply of water vapor for local recycled precipitation directly but also decreases the convective available potential energy and hence the conversion efficiency of atmospheric moisture into rainfall. The urbanization-induced variations in local recycled precipitation were found to be correlated with the net atmospheric moisture flux on a monthly time scale.

[Analysis of urban forest landscape pattern in Hefei].

PubMed

Wu, Zemin; Wu, Wenyou; Gao, Jian; Zhang, Shaojie

2003-12-01

Based on the theory and methodology of landscape ecology, the landscape pattern of the study area (17.6 km2) in the downtown of Hefei was analyzed by using the techniques of RS, GPS and GIS. The object was to provide a comprehensive method to study urban forest structure and its function in environmental improvement. The results showed that there were 5 major landscape elements, i.e., building and hard pavement surface, water, road, urban forest, and general green land in the area. The landscape matrix was building and pavement surface, occupied 73.13% of total land. Road was the typical corridor element in the city and occupied 6.89%. Green land occupied 11.44%, in which, urban forest patch occupied 9.18%. There were 408 urban forest patches, with an area of 161.16 hm2. The average area of the patch was 0.396 hm2, and the maximum area was 12 hm2. 48% of urban forest patch was identified as small scale patches with < 500 m2 of area, and only 8.6% of them was larger than 1 hm2. The number of general green land patch was 255, with an area of 39.74 hm2, which accounted for 2.26% of land area, and its average and maximum area was 0.1558 hm2 and 3.86 hm2, respectively. There were 147 water patches, with an area of 149.93 hm2, and occupied 8.54% of land, and the average and maximum area of the patch was 1.02 hm2 and 16 hm2, respectively. In the study area, both of the Shannon-Weiner landscape diversity index and evenness were low, only 0.928 and 0.576, respectively. In addition, the dominance of urban forest patch and general green land was 0.39 showing that the two landscape elements had a certain influence on the environment of the study area. The concept of interior habitat for forest was introduced in this paper, which was employed to make a scale class system of urban forest patch. The threshold area with interior habitat for urban forest patch was 9800 m2, and there was 31.69 hm2 of interior habitat of urban forest in total, which occupied 19.7% of the total area of urban forest patch. This situation was not favorable for providing more habitats to support species diversity. It's suggested that the concept of interior habitat could be employed to identify urban forest patch, and a scale system of small scale patch of urban forest-middle patch-large patch-extra large patch was build in the paper. Based on this system, the ratio of different scales of urban forest patch in the study area should be 2:2:2:3. The authors also suggested that larger pieces (1.5-3.0 hm2) of urban forest patch should be built, and more urban forests should be established in the northeastern part of the city in the future.

Evaluating the effects of urbanization and land-use planning using ground-water and surface-water models

USGS Publications Warehouse

Hunt, R.J.; Steuer, J.J.

2001-01-01

Why are the effects of urbanization a concern? As the city of Middleton, Wisconsin, and its surroundings continue to develop, the Pheasant Branch watershed (fig.l) is expected to undergo urbanization. For the downstream city of Middleton, urbanization in the watershed can mean increased flood peaks, water volume and pollutant loads. More subtly, it may also reduce water that sustains the ground-water system (called "recharge") and adversely affect downstream ecosystems that depend on ground water such as the Pheasant Branch Springs (hereafter referred to as the Springs). The relation of stormwater runoff and reduced ground-water recharge is complex because the surface-water system is coupled to the underlying ground-water system. In many cases there is movement of water from one system to the other that varies seasonally or daily depending on changing conditions. Therefore, it is difficult to reliably determine the effects of urbanization on stream baseflow and spring flows without rigorous investigation. Moreover, mitigating adverse effects after development has occurred can be expensive and administratively difficult. Overlying these concerns are issues such as stewardship of the resource, the rights of the public, and land owners' rights both of those developing their land and those whose land is affected by this development. With the often- contradictory goals, a scientific basis for assessing effects of urbanization and effectiveness of mitigation measures helps ensure fair and constructive decision-making. The U.S. Geological Survey, in cooperation with the City of Middleton and Wisconsin Department of Natural Resources, completed a study that helps address these issues through modeling of the hydrologic system. This Fact Sheet discusses the results of this work.

Urban biophysical composition and its impact on thermal changes and ecosystem production

NASA Astrophysics Data System (ADS)

Sannigrahi, Srikanta; Rahmat, Shahid; Bhatt, Sandeep

2017-04-01

Human driving forces, especially, urbanization, population pressure, and socioeconomic development are significantly changing the efficiency of ecosystem service provision in an urban ecosystem. Greater Hyderabad Municipal Corporation (GHMC) is the sixth largest urban metropolitan region in India had faced an alarming pace of urban expansion from 1973 to 2015. MODerate Resolution Imaging Spectroradiometer (MODIS) thermal products MOD11A2 and surface reflectance products MOD09A1 were employed in this work to simulate areal and temporal dynamics of Urban Heat Island (UHI) and Diurnal Temperature Range (DTR) of the GHMC region from 2002 to 2015. A Light Use Efficiency (LUE) based Vegetation Photosynthesis Model (VPM) was adopted in this work to quantify Net Primary Production (NPP) and to assess the spatiotemporal changes of NPP during 2002 to 2015. MODIS yearly NPP products MOD17A3 were applied here for the purpose of model validation. Linear Spectral Mixture Analysis (LSMA) technique was employed in this research to generate impervious surface fraction image of GHMC. Spatially explicit gas regulation service included as a regulatory ecosystem service to assess the trade-off between economic viability and ecosystem conservation. Acute urban expansion (over 200%) is mainly accounted to changes the Land Surface Temperature (LST) over 3°C to 4°C in the inner city region during 1991 to 2015. Surface vegetation and moisture dynamics have been evaluated by incorporating Normalized Difference Vegetation Index (NDVI), Normalized Difference Built-up Index (NDBI), Normalized Difference Bareness Index (NDBaI) and Land Surface Water Index (LSWI) for the year of 2002, 2011 and 2015, respectively. The four distinct UHI cluster, i.e. H-H, H-L, L-H & L-L were retrieved from the segmentation of estimated LST using Local Indicators Spatial Autocorrelation (LISA) technique. Further, the Getis-Ord-Gi hotspot analysis method has been employed to identify the local proximity of spatial hot and cold UHI clusters. The areal coverage of built-up urban class was changed from 208.11sq.km in 1973 to 419.55 sq.km in 2015 with 5.03 sq.km/year expansion rate. The selected biophysical indices are found highly sensitive to the changes in land use and land cover (LULC). LST hotspot (H-H) in 2002 was observed in the central and the southeast portion of the region due to the presence of higher thermal anomalies and high concentration of LST (°C). The Island (H-L) part of the city was mostly covered by the built-up urban area in 2002 exhibiting the highest concentration of LST, whereas the mean LST (°C) of the neighboring region is below than the average. GiZScore with low standard deviation value proven the existence of active hotspot of LST and UHI over the central urbanized area in GHMC.A strong negative correlation has found between the selected human driving forces: UHI, LST, population density, settlement density and impervious fraction with NPP ensembles the facts of human control in an urban ecosystem. This study demonstrated the necessity of proper quantification and valuation of urban ecosystem services to achieve effective and efficient decision for urban ecosystem management.

Distinguishing spatiotemporal variability of sediment sources in small urbanized catchment as a response to urban expansion

NASA Astrophysics Data System (ADS)

Belyaev, Vladimir; Feoktistov, Artem; Huygens, Dries; Shamshurina, Eugenia; Golosov, Valentin

2014-05-01

Understanding hydrological response and geomorphic behavior of small catchments in urban environments, especially those experiencing urban expansion, represents serious and important problem which has not yet been given an adequate research attention. Urbanization exerts profound and diverse impacts on catchment characteristics, particularly by increasing surface runoff coefficients, peak flow discharges and rates of flash flood waves propagation as a result of widespread appearance of buildings and paved surfaces with practically zero infiltration capacities. Another essential influence of urbanization on small catchment hydrological regimes is associated with significant changes of natural topography (from relatively minor modifications such as grading of steeper slopes to complete transformations including total filling of gullies and small valleys, transfer of small streams from surface into underground pipes or collectors, etc.) combined with creation of systems of concrete-protected surface drainages and underground storm flow sewages. Such activities can result in substantial changes of runoff- and sediment-contributing areas for the remaining gullies and small valleys in comparison to the pre-urbanization conditions, causing dramatic increase of fluvial activity in some of those and much lower flow discharges in others. In addition, gullies and small valleys in urban settlements often become sites of dumping for both dry and liquid domestic and industrial wastes, thus being major pathways for dissolved and particle-bound pollutant transfer into perennial streams and rivers. All the problems listed require detailed hydrological and geomorphic investigations in order to provide sound basis for developing appropriate measures aimed to control and decrease urban erosion, sediment redistribution, pollution of water bodies, damage to constructions and communications. Recent advances in sediment tracing and fingerprinting techniques provide promising opportunities for distinguishing contributions of different sediment sources into catchment sediment budgets on a reliable quantitative basis. In combination with microstratigraphic differentiation and dating of sediment in continuous deposition zones by 137Cs depth distribution curves and available land use records, spatial and temporal variability of sediment sources and sinks can be reconstructed for the last several decades. That is especially important for catchments which experienced profound land use changes such as transition from pristine or agriculture-dominated to urbanized environment. The example presented here describes the results of reconstruction of changing sediment source types, contributions and spatial patterns for small reservoir catchment within the city of Kursk (Sredenerusskaya Upland, Central European Russia). Combination of compound specific stable isotopes, 137Cs, sediment grain size composition, land use information for several time intervals and daily rainfall record for the Kursk meteorological station (conveniently located within the study catchment) have been employed in order to evaluate major sediment sources within the catchment, their spatial pattern and temporal changes and compare those to history of reservoir sedimentation. The reservoir is situated on the Kur River - small river which gave its name to the city itself. The dam and reservoir were constructed and put into operation in 1969, thus the beginning of its infill is located stratigraphically later than the main peak of the global 137Cs fallout. It has been found that transition from dominantly agricultural land use to urbanized conditions caused decrease of contribution of soil erosion from cultivated land and increase of that of the active gullies into reservoir sedimentation. However, it is important to note that during extreme runoff events contribution of sediment originated from soil erosion on arable land still remains dominant, even though its area within the catchment recently became very limited.

Stormwater dissolved organic matter: influence of land cover and environmental factors.

PubMed

McElmurry, Shawn P; Long, David T; Voice, Thomas C

2014-01-01

Dissolved organic matter (DOM) plays a major role in defining biological systems and it influences the fate and transport of many pollutants. Despite the importance of DOM, understanding of how environmental and anthropogenic factors influence its composition and characteristics is limited. This study focuses on DOM exported as stormwater from suburban and urban sources. Runoff was collected before entering surface waters and DOM was characterized using specific ultraviolet absorbance at 280 nm (a proxy for aromaticity), molecular weight, polydispersity and the fraction of DOM removed from solution via hydrophobic and H-bonding mechanisms. General linear models (GLMs) incorporating land cover, precipitation, solar radiation and selected aqueous chemical measurements explained variations in DOM properties. Results show (1) molecular characteristics of DOM differ as a function of land cover, (2) DOM produced by forested land is significantly different from other landscapes, particularly urban and suburban areas, and (3) DOM from land cover that contains paved surfaces and sewers is more hydrophobic than from other types of land cover. GLMs incorporating environmental factors and land cover accounted for up to 86% of the variability observed in DOM characteristics. Significant variables (p < 0.05) included solar radiation, water temperature and water conductivity.

New York City Impact on Regional Heat Wave

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ortiz, Luis E.; Schoonen, Martin

Abstract Extreme heat events are projected to increase in magnitude and frequency throughout this century due to increasing global temperatures, making it critically important to acquire improved understanding of their genesis and interactions with large cities. This study presents an application of the factor separation method to assess combined impacts of a synoptic scale heat wave, urban land cover, and urban energy and momentum fluxes on temperatures and winds over New York City via use of high resolution simulations (1 km grid spacing) with an urbanized WRF model. Results showed that, while the heat wave had the largest contribution tomore » temperatures (> 8°C), urban surface factors matched it in highly urbanized areas. Surface factors matched this in highly urbanized areas during night and early morning hours, with contributions up to 5°C, when calm land breeze conditions result in a strong urban heat island. Positive interactions between all factors during morning and nighttime indicate urban heat island amplification of up to 4°C during the heat wave. Midtown Manhattan vertical cross-sections, where urban canopies are most dense, showed a change in the sign (from positive to negative) of the contribution of the urban fluxes between night and day below 500 m, possibly due to radiation blocking and increased thermal storage by buildings as well as frictional effects opposing the incoming warm air.« less

New York City Impact on Regional Heat Wave

DOE PAGES

Ortiz, Luis E.; Schoonen, Martin

2018-04-01

Abstract Extreme heat events are projected to increase in magnitude and frequency throughout this century due to increasing global temperatures, making it critically important to acquire improved understanding of their genesis and interactions with large cities. This study presents an application of the factor separation method to assess combined impacts of a synoptic scale heat wave, urban land cover, and urban energy and momentum fluxes on temperatures and winds over New York City via use of high resolution simulations (1 km grid spacing) with an urbanized WRF model. Results showed that, while the heat wave had the largest contribution tomore » temperatures (> 8°C), urban surface factors matched it in highly urbanized areas. Surface factors matched this in highly urbanized areas during night and early morning hours, with contributions up to 5°C, when calm land breeze conditions result in a strong urban heat island. Positive interactions between all factors during morning and nighttime indicate urban heat island amplification of up to 4°C during the heat wave. Midtown Manhattan vertical cross-sections, where urban canopies are most dense, showed a change in the sign (from positive to negative) of the contribution of the urban fluxes between night and day below 500 m, possibly due to radiation blocking and increased thermal storage by buildings as well as frictional effects opposing the incoming warm air.« less

Land Use Change and Agricultural Land Fragmentation due to Anthropogenic Activities in an Hot Spot Area: A Case Study for Thrace Region of Turkey

NASA Astrophysics Data System (ADS)

Altürk, Bahadır; Konukcu, Fatih

2017-04-01

Agricultural lands that supply food, energy and ecosystem services for human life have been lost due to anthropogenic activities such as construction of roads, urban and industry areas. The significant reasons for the increase of artificial surfaces were poorly planned economic decisions by the government and internal migration due to this poorly planning. Unplanned urban sprawl also give rise to land fragmentation. Fragmentation of agricultural land affects both the agricultural production capacity and rural sustainable employment. In this study: i) Land use changes between 1990-2014 period were assessed using remotely sensed data and ii) Spatial and temporal agricultural land fragmentation were investigated using landscape pattern indice (effective mesh size), Morphological Spatial Pattern Analysis (MSPA) and Entropy method for 25 years period. The selected"hot spot" study area is located on east Thrace region of Turkey, being the service and industrial development zone where agricultural activities, water resources and natural habitat have been damaged due to rapid urban and industrial development for about 25 years. The results showed that agricultural lands decreased 6.44%, urban areas increased 111.68% and industry areas increased 251.19% during this 25 years period. Additionally, fragmentation analyses demonstrated that core agricultural areas sharply decreased and relative fragmentation (effective mesh size) increased from 50.68% to 56.77% during 1990 and 2014.

Prediction of channel degradation rates in urbanizing watersheds

USDA-ARS?s Scientific Manuscript database

In urbanizing watersheds, as land use changes, and storm sewers and impervious surfaces are increased, both the frequency and magnitude of discharge increase, resulting in stream channel down-cutting and widening and related loss of structures and engineering works. A simple model for assessing the ...

High-resolution maps of forest-urban watersheds present an opportunity for ecologists and managers

EPA Science Inventory

Dense populations of people and abundant impervious surfaces contribute to poor water quality and increased flooding in forest-urban watersheds. Green infrastructure mitigates these effects, but precisely quantifying benefits is difficult because most land cover maps rely on coar...

Socioeconomic indicators of heat-related health risk supplemented with remotely sensed data

PubMed Central

Johnson, Daniel P; Wilson, Jeffrey S; Luber, George C

2009-01-01

Background Extreme heat events are the number one cause of weather-related fatalities in the United States. The current system of alert for extreme heat events does not take into account intra-urban spatial variation in risk. The purpose of this study is to evaluate a potential method to improve spatial delineation of risk from extreme heat events in urban environments by integrating sociodemographic risk factors with estimates of land surface temperature derived from thermal remote sensing data. Results Comparison of logistic regression models indicates that supplementing known sociodemographic risk factors with remote sensing estimates of land surface temperature improves the delineation of intra-urban variations in risk from extreme heat events. Conclusion Thermal remote sensing data can be utilized to improve understanding of intra-urban variations in risk from extreme heat. The refinement of current risk assessment systems could increase the likelihood of survival during extreme heat events and assist emergency personnel in the delivery of vital resources during such disasters. PMID:19835578

Leaf breakdown in streams differing in catchment land use

USGS Publications Warehouse

Paul, M.J.; Meyer, J.L.; Couch, C.A.

2006-01-01

1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south-eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar-sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day-1) and urban (0.0474 day-1) streams than in suburban (0.0173 day-1) and forested (0.0100 day-1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land-use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff. ?? 2006 The Authors.

Effects of Explicit Urban-Canopy Representation on Local Circulations Above a Tropical Mega-City

NASA Astrophysics Data System (ADS)

Flores Rojas, José L.; Pereira Filho, Augusto J.; Karam, Hugo A.; Vemado, Felipe; Masson, Valéry

2018-01-01

The Advanced Regional Prediction System (ARPS) is coupled with the tropical town energy budget (tTEB) scheme to analyze the effects of the urban canopy circulation over the metropolitan area of São Paulo and its interactions with the sea breeze and mountain-valley circulation in the eastern state of São Paulo, Brazil. Two experiments are carried out for the typical sea-breeze event occurring on 22 August 2014 under weak synoptic forcing and clear-sky conditions: (a) a control run with the default semi-desert surface parametrization and; (b) a tTEB run for the urban canopy of São Paulo. A realistic land-use database over the south-eastern domain of Brazil is used in the downscaling simulation to a horizontal grid resolution of 3 km. Our results indicate that ARPS effectively simulates features of the nighttime and early morning land-breeze circulation, which is affected by the surrounding hills and the nocturnal heat island of São Paulo. By early afternoon, the south-eastern sea-breeze circulation moves inland perpendicular to the upslope of the Serra do Mar scarp, which generates a line of moisture convergence and updrafts further inland. Later, the convergence line reaches São Paulo and interacts with the circulation arising from the urban heat island (UHI), which increases the moisture convergence and strength of updrafts. The surface energy balance indicates that the UHI is caused by large sensible heat storage within the urban canopy during the day, which is later released in the afternoon and at night. The simulations are verified with available radiosonde and surface weather station data, land-surface-temperature estimates from the moderate resolution imaging spectroradiometer, as well as the National Center for Atmospheric Research reanalysis databases. The three-dimensional geometry of the urban canyons within the tTEB scheme consistently improves the thermodynamically-induced circulation over São Paulo.

Using local climate zone classifications to assess the influence of urban morphology on the urban heat island effect

NASA Astrophysics Data System (ADS)

Satcher, P. S.; Brunsell, N. A.

2017-12-01

Alterations to land cover resulting from urbanization interact with the atmospheric boundary layer inducing elevated surface and air temperatures, changes to the surface energy balance (SEB), and modifications to regional circulations and climates. These changes pose risks to public health, ecological systems, and have the potential to affect economic interests. We used Google Earth Engine's Landsat archive to classify local climate zones (LCZ) that consist of ten urban and seven non-urban classes to examine the influence of urban morphology on the urban heat island (UHI) effect. We used geostatistical methods to determine the significance of the spatial distributions of LCZs to land surface temperatures (LST) and normalized difference vegetation index (NDVI) Moderate Resolution Imaging Spectroradiometer (MODIS) products. We used the triangle method to assess the variability of SEB partitioning in relation to high, medium, and low density LCZ classes. Fractional vegetation cover (Fr) was calculated using NDVI data. Linear regressions of observations in Fr-LST space for select LCZ classes were compared for selected eight-day periods to determine changes in energy partitioning and relative soil moisture availability. The magnitude of each flux is not needed to determine changes to the SEB. The regressions will examine near surface soil moisture, which is indicative of how much radiation is partitioned into evaporation. To compare changes occurring over one decade, we used MODIS NDVI and LST data from 2005 and 2015. Results indicated that variations in the SEB can be detected using the LCZ classification method. The results from analysis in Fr-LST space of the annual cycles over several years can be used to detect changes in the SEB as urbanization increases.

A method for locating potential tree-planting sites in urban areas: a case study of Los Angeles, USA

Treesearch

Chunxia Wua; Qingfu Xiaoa; Gregory E. McPherson

2008-01-01

A GIS-based method for locating potential tree-planting sites based on land cover data is introduced. Criteria were developed to identify locations that are spatially available for potential tree planting based on land cover, sufficient distance from impervious surfaces, a minimum amount of pervious surface, and no crown overlap with other trees. In an ArcGIS...

Impervious Surfaces Alter Soil Bacterial Communities in Urban Areas: A Case Study in Beijing, China

PubMed Central

Hu, Yinhong; Dou, Xiaolin; Li, Juanyong; Li, Feng

2018-01-01

The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete), permeable pavement (bricks with round holes), shrub coverage (Buxus megistophylla Levl.), lawns (Festuca elata Keng ex E. Alexeev), and roadside trees (Sophora japonica Linn.) in Beijing, to explore the response of bacteria to impervious surfaces. The soil bacterial communities were addressed by high-throughput sequencing of the bacterial 16S rRNA gene. We found that Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, and Firmicutes were the predominant phyla in urban soils. Soil from impervious surfaces presented a lower bacterial diversity, and differed greatly from other types of land cover. Soil bacterial diversity was predominantly affected by Zn, dissolved organic carbon (DOC), and soil moisture content (SMC). The composition of the bacterial community was similar under shrub coverage, roadside trees, and lawns, but different from beneath impervious surfaces and permeable pavement. Variance partitioning analysis showed that edaphic properties contributed to 12% of the bacterial community variation, heavy metal pollution explained 3.6% of the variation, and interaction between the two explained 33% of the variance. Together, our data indicate that impervious surfaces induced changes in bacterial community composition and decrease of bacterial diversity. Interactions between edaphic properties and heavy metals were here found to change the composition of the bacterial community and diversity across areas with different types of land cover, and soil properties play a more important role than heavy metals. PMID:29545776

A GIS approach to urban heat island research: The case of Huntsville, Alabama

NASA Technical Reports Server (NTRS)

Lo, Chor Pong

1994-01-01

The urban heat island represents a case of inadvertent human modification of climate in an urban environment. Urbanization changes the nature of the surface and atmospheric properties of a region. As a result, radiation balance in the urban areas is altered and sensible heat is added to the point that urban areas are warmer than surrounding rural areas. At the boundary between the rural and urban area, a sharp rise in temperature occurs, culminating to a peak temperature at the central business district of the city, hence the name 'urban heat island'. The extent and intensity of the urban heat island are a function of population size, land use, and topography. Because the urban heat island exhibits spatial variations of temperatures, the use of Geographic Information System (GIS) is appropriate. The research on the urban heat island focuses on the acquisition of 15 bands of visible and thermal infrared data (ranging from 0.45 to 12.2 microns) from an aerial platform using NASA's ATLAS (Airborne Thermal/Visible Land Application Sensor) over Huntsville, Alabama. The research reported in this paper is an analysis of the impact of population, land use, and topography on the shape of the urban heat island that could be developed in Huntsville using the GIS approach. The outcome of this analysis can then be verified using the acquired remotely sensed data.

High-resolution simulation of heatwave events in New York City

NASA Astrophysics Data System (ADS)

Ramamurthy, P.; Li, D.; Bou-Zeid, E.

2017-04-01

Heatwave intensity and frequency are predicted to increase in the coming years, and this will bear adverse consequences to the environmental well-being and the socio-economic fabric in urbanized areas. The hazardous combination of increased heat storage and reduced water retention capacities of the land surface make the urban areas warmer than the surrounding rural areas in what is commonly known as the urban heat island (UHI) effect. The primary motives of this study are to quantify the interaction of this city-scale UHI with synoptic-scale heatwave episodes and to analyze the factors that mediate this interaction. A modified version of the Weather Research and Forecasting model (WRF) is utilized to simulate two heatwave episodes in New York City. The land surface scheme in the default WRF model is modified to better represent the surface to atmosphere exchanges over urban areas. Our results indicate that during the heatwave episodes, the daily-averaged UHI in NYC increased by 1.5 K. Furthermore, most of this amplification occurs in the mid-afternoon period when the temperatures peak. Wind direction and urban-rural contrasts in available energy and moisture availability are found to have significant and systematic effects on the UHI, but wind speed plays a secondary role.

An Investigation of the Influence of Urban Areas on Rainfall Using the TRMM Satellite and a Cloud-Mesoscale Model

NASA Astrophysics Data System (ADS)

Shepherd, J.

2002-05-01

A recent paper by Shepherd et al. (in press at Journal of Applied Meteorology) used rainfall data from the Precipitation Radar on NASA's Tropical Rainfall Measuring Mission's (TRMM) satellite to identify warm season rainfall anomalies downwind of major urban areas. Data (PR) were employed to identify warm season rainfall (1998-2000) patterns around Atlanta, Montgomery, Nashville, San Antonio, Waco, and Dallas. Results are consistent with METROMEX studies of St. Louis almost two decades ago and with more recent studies near Atlanta. A convective-mesoscale model with extensive land-surface processes is currently being employed to (a) determine if an urban heat island (UHI) thermal perturbation can induce a dynamic response to affect rainfall processes and (b) quantify the impact of the following three factors on the evolution of rainfall: (1) urban surface roughness, (2) magnitude of the UHI temperature anomaly, and (3) physical size of the UHI temperature anomaly. The sensitivity experiments are achieved by inserting a slab of land with urban properties (e.g. roughness length, albedo, thermal character) within a rural surface environment and varying the appropriate lower boundary condition parameters. The study will discuss the feasibility of utilizing satellite-based rainfall estimates for examining rainfall modification by urban areas on global scales and over longer time periods. The talk also introduces very preliminary results from the modeling component of the study.

Seasonal albedo of an urban/rural landscape from satellite observations

NASA Technical Reports Server (NTRS)

Brest, Christopher L.

1987-01-01

Using data from 27 calibrated Landsat observations of the Hartford, Connecticut area, the spatial distribution and seasonal variation of surface reflectance and albedo were examined. Mean values of visible reflectance, near-IR reflectance, and albedo are presented (for both snow-free and snow-cover observations) according to 14 land use/land cover categories. A diversity of albedo values was found to exist in this type of environment, associated with land cover. Many land-cover categories display a seasonal dependence, with intracategory seasonal differences being of comparable magnitude to intercategory differences. Key factors in determining albedo (and its seasonal dynamics) are the presence or absence of vegetation and the canopy structure. Snow-cover/snow-free differences range from a few percent (for urban land covers) to over 40 percent (for low-canopy vegetation).

GIS based optimal impervious surface map generation using various spatial data for urban nonpoint source management.

PubMed

Lee, Cholyoung; Kim, Kyehyun; Lee, Hyuk

2018-01-15

Impervious surfaces are mainly artificial structures such as rooftops, roads, and parking lots that are covered by impenetrable materials. These surfaces are becoming the major causes of nonpoint source (NPS) pollution in urban areas. The rapid progress of urban development is increasing the total amount of impervious surfaces and NPS pollution. Therefore, many cities worldwide have adopted a stormwater utility fee (SUF) that generates funds needed to manage NPS pollution. The amount of SUF is estimated based on the impervious ratio, which is calculated by dividing the total impervious surface area by the net area of an individual land parcel. Hence, in order to identify the exact impervious ratio, large-scale impervious surface maps (ISMs) are necessary. This study proposes and assesses various methods for generating large-scale ISMs for urban areas by using existing GIS data. Bupyeong-gu, a district in the city of Incheon, South Korea, was selected as the study area. Spatial data that were freely offered by national/local governments in S. Korea were collected. First, three types of ISMs were generated by using the land-cover map, digital topographic map, and orthophotographs, to validate three methods that had been proposed conceptually by Korea Environment Corporation. Then, to generate an ISM of higher accuracy, an integration method using all data was proposed. Error matrices were made and Kappa statistics were calculated to evaluate the accuracy. Overlay analyses were performed to examine the distribution of misclassified areas. From the results, the integration method delivered the highest accuracy (Kappa statistic of 0.99) compared to the three methods that use a single type of spatial data. However, a longer production time and higher cost were limiting factors. Among the three methods using a single type of data, the land-cover map showed the highest accuracy with a Kappa statistic of 0.91. Thus, it was judged that the mapping method using the land-cover map is more appropriate than the others. In conclusion, it is desirable to apply the integration method when generating the ISM with the highest accuracy. However, if time and cost are constrained, it would be effective to primarily use the land-cover map. Copyright © 2017 Elsevier Ltd. All rights reserved.

Temporal and spatial changes of land use and landscape in a coal mining area in Xilingol grassland

NASA Astrophysics Data System (ADS)

Guan, Chunzhu; Zhang, Baolin; Li, Jiannan; Zhao, Junling

2017-01-01

Coal mining, particularly surface mining, inevitably disturbs land. According to Landsat images acquired over Xilingol grassland in 2005, 2009 and 2015, land uses were divided into seven classes, i. e., open stope, stripping area, waste-dump area, mine industrial area, farmland, urban area and the original landscape (grassland), using supervised classification and human-computer interactive interpretation. The overall classification accuracies were 97.72 %, 98.43 % and 96.73 %, respectively; the Kappa coefficients were 0.95, 0.97 and 0.95, respectively. Analysis on LUCC (Land Use and Cover Change) showed that surface coal mining disturbed grassland ecosystem: grassland decreased by 8661.15 hm2 in 2005-2015. The area and proportion of mining operation areas (open stope, stripping area, waste-dump area, mine industrial field) increased, but those of grassland decreased continuously. Transfer matrix of land use changes showed that waste-dump had the largest impacts in mining disturbance, and that effective reclamation of waste-dump areas would mitigate eco-environment destruction, as would be of great significance to protect fragile grassland eco-system. Six landscape index showed that landscape fragmentation increased, and the influences of human activity on landscape was mainly reflected in the expansion of mining area and urban area. Remote sensing monitoring of coal surface mining in grassland would accurately demonstrate the dynamics and trend of LUCC, providing scientific supports for ecological reconstruction in surface mining area.

Impacts of urbanization on river flow frequency: A controlled experimental modeling-based evaluation approach

USDA-ARS?s Scientific Manuscript database

Changes in land use are likely to cause a non-linear response in watershed hydrology. Specifically, small increases in urban expansion may greatly increase surface runoff while decreasing infiltration, impacting aquifer recharge and changing streamflow regimes. Quantifying the effects of urbanizatio...

Effects of urbanization on heavy metal accumulation in surface soils, Beijing.

PubMed

Wang, Meie; Liu, Rui; Chen, Weiping; Peng, Chi; Markert, Bernd

2018-02-01

Urbanization processes affect the accumulation of heavy metals in urban soils. Effects of urbanization on heavy metal accumulation in soils were studied using Beijing as an example. It has been suggested that the ecological function of vegetation covers shifting from natural to agricultural settings and then to urban greenbelts could increase the zinc (Zn) concentrations of soils successively. The Zn concentration of urban soils was significantly correlated to the percentage of the impervious land surface at the 500m×500m spatial scale. For urban parks, the age or years since the development accounted for 80% of the variances of cadmium (Cd) and Zn in soils. The population density, however, did not affect the heavy metal distributions in urban soils. To conclude, the urban age turned out to be a notable factor in quantifying heavy metal accumulation in urban soils. Copyright © 2017. Published by Elsevier B.V.

Monitoring Urban Heat Island Through Google Earth Engine: Potentialities and Difficulties in Different Cities of the United States

NASA Astrophysics Data System (ADS)

Ravanelli, R.; Nascetti, A.; Cirigliano, R. V.; Di Rico, C.; Monti, P.; Crespi, M.

2018-04-01

The aim of this work is to exploit the large-scale analysis capabilities of the innovative Google Earth Engine platform in order to investigate the temporal variations of the Urban Heat Island phenomenon as a whole. A intuitive methodology implementing a largescale correlation analysis between the Land Surface Temperature and Land Cover alterations was thus developed.The results obtained for the Phoenix MA are promising and show how the urbanization heavily affects the magnitude of the UHI effects with significant increases in LST. The proposed methodology is therefore able to efficiently monitor the UHI phenomenon.

Attribution of local climate zones using a multitemporal land use/land cover classification scheme

NASA Astrophysics Data System (ADS)

Wicki, Andreas; Parlow, Eberhard

2017-04-01

Worldwide, the number of people living in an urban environment exceeds the rural population with increasing tendency. Especially in relation to global climate change, cities play a major role considering the impacts of extreme heat waves on the population. For urban planners, it is important to know which types of urban structures are beneficial for a comfortable urban climate and which actions can be taken to improve urban climate conditions. Therefore, it is essential to differ between not only urban and rural environments, but also between different levels of urban densification. To compare these built-up types within different cities worldwide, Stewart and Oke developed the concept of local climate zones (LCZ) defined by morphological characteristics. The original LCZ scheme often has considerable problems when adapted to European cities with historical city centers, including narrow streets and irregular patterns. In this study, a method to bridge the gap between a classical land use/land cover (LULC) classification and the LCZ scheme is presented. Multitemporal Landsat 8 data are used to create a high accuracy LULC map, which is linked to the LCZ by morphological parameters derived from a high-resolution digital surface model and cadastral data. A bijective combination of the different classification schemes could not be achieved completely due to overlapping threshold values and the spatially homogeneous distribution of morphological parameters, but the attribution of LCZ to the LULC classification was successful.

Land use change and human health

NASA Astrophysics Data System (ADS)

Patz, Jonathan A.; Norris, Douglas E.

Disease emergence events have been documented following several types of land use change. This chapter reviews several health-relevant land use changes recognized today, including: 1) urbanization and urban sprawl; 2) water projects and agricultural development; 3) road construction and deforestation in the tropics; and 4) regeneration of temperate forests. Because habitat or climatic change substantially affects intermediate invertebrate hosts involved in many prevalent diseases, this chapter provides a basic description of vector-borne disease biology as a foundation for analyzing the effects of land use change. Urban sprawl poses health challenges stemming from heat waves exacerbated by the "urban heat island" effect, as well as from water contamination due to expanses of impervious road and concrete surfaces. Dams, irrigation and agricultural development have long been associated with diseases such as schistosomiasis and filariasis. Better management methods are required to address the trade-offs between expanded food production and altered habitats promoting deadly diseases. Deforestation can increase the nature and number of breeding sites for vector-borne diseases, such as malaria and onchocerciasis. Human host and disease vector interaction further increases risk, as can a change in arthropod-vector species composition.

Integrated simulation of consumptive use and land subsidence in the Central Valley, California, for the past and for a future subject to urbanization and climate change

USGS Publications Warehouse

Hanson, Randall T.; Flint, Alan L.; Faunt, Claudia C.; Cayan, Daniel R.; Flint, Lorraine E.; Leake, Stanley A.; Schmid, Wolfgang

2010-01-01

Competition for water resources is growing throughout California, particularly in the Central Valley where about 20% of all groundwater used in the United States is consumed for agriculture and urban water supply. Continued agricultural use coupled with urban growth and potential climate change would result in continued depletion of groundwater storage and associated land subsidence throughout the Central Valley. For 1962-2003, an estimated 1,230 hectare meters (hm3) of water was withdrawn from fine-grained beds, resulting in more than three meters (m) of additional land subsidence locally. Linked physically-based, supply-constrained and emanddriven hydrologic models were used to simulate future hydrologic conditions under the A2 climate projection scenario that assumes continued "business as usual" greenhouse gas emissions. Results indicate an increased subsidence in the second half of the twenty-first century. Potential simulated land subsidence extends into urban areas and the eastern side of the valley where future surface-water deliveries may be depleted. 

Modelling the Relationship Between Land Surface Temperature and Landscape Patterns of Land Use Land Cover Classification Using Multi Linear Regression Models

NASA Astrophysics Data System (ADS)

Bernales, A. M.; Antolihao, J. A.; Samonte, C.; Campomanes, F.; Rojas, R. J.; dela Serna, A. M.; Silapan, J.

2016-06-01

The threat of the ailments related to urbanization like heat stress is very prevalent. There are a lot of things that can be done to lessen the effect of urbanization to the surface temperature of the area like using green roofs or planting trees in the area. So land use really matters in both increasing and decreasing surface temperature. It is known that there is a relationship between land use land cover (LULC) and land surface temperature (LST). Quantifying this relationship in terms of a mathematical model is very important so as to provide a way to predict LST based on the LULC alone. This study aims to examine the relationship between LST and LULC as well as to create a model that can predict LST using class-level spatial metrics from LULC. LST was derived from a Landsat 8 image and LULC classification was derived from LiDAR and Orthophoto datasets. Class-level spatial metrics were created in FRAGSTATS with the LULC and LST as inputs and these metrics were analysed using a statistical framework. Multi linear regression was done to create models that would predict LST for each class and it was found that the spatial metric "Effective mesh size" was a top predictor for LST in 6 out of 7 classes. The model created can still be refined by adding a temporal aspect by analysing the LST of another farming period (for rural areas) and looking for common predictors between LSTs of these two different farming periods.

Assessment of land surface temperature and heat fluxes over Delhi using remote sensing data.

PubMed

Chakraborty, Surya Deb; Kant, Yogesh; Mitra, Debashis

2015-01-15

Surface energy processes has an essential role in urban weather, climate and hydrosphere cycles, as well in urban heat redistribution. The research was undertaken to analyze the potential of Landsat and MODIS data in retrieving biophysical parameters in estimating land surface temperature & heat fluxes diurnally in summer and winter seasons of years 2000 and 2010 and understanding its effect on anthropogenic heat disturbance over Delhi and surrounding region. Results show that during years 2000-2010, settlement and industrial area increased from 5.66 to 11.74% and 4.92 to 11.87% respectively which in turn has direct effect on land surface temperature (LST) and heat fluxes including anthropogenic heat flux. Based on the energy balance model for land surface, a method to estimate the increase in anthropogenic heat flux (Has) has been proposed. The settlement and industrial areas has higher amounts of energy consumed and has high values of Has in all seasons. The comparison of satellite derived LST with that of field measured values show that Landsat estimated values are in close agreement within error of ±2 °C than MODIS with an error of ±3 °C. It was observed that, during 2000 and 2010, the average change in surface temperature using Landsat over settlement & industrial areas of both seasons is 1.4 °C & for MODIS data is 3.7 °C. The seasonal average change in anthropogenic heat flux (Has) estimated using Landsat & MODIS is up by around 38 W/m(2) and 62 W/m(2) respectively while higher change is observed over settlement and concrete structures. The study reveals that the dynamic range of Has values has increased in the 10 year period due to the strong anthropogenic influence over the area. The study showed that anthropogenic heat flux is an indicator of the strength of urban heat island effect, and can be used to quantify the magnitude of the urban heat island effect. Copyright © 2013 Elsevier Ltd. All rights reserved.

Surface Heat Balance Analysis of Tainan City on March 6, 2001 Using ASTER and Formosat-2 Data

PubMed Central

Kato, Soushi; Yamaguchi, Yasushi; Liu, Cheng-Chien; Sun, Chen-Yi

2008-01-01

The urban heat island phenomenon occurs as a mixed result of anthropogenic heat discharge, decreased vegetation, and increased artificial impervious surfaces. To clarify the contribution of each factor to the urban heat island, it is necessary to evaluate the surface heat balance. Satellite remote sensing data of Tainan City, Taiwan, obtained from Terra ASTER and Formosat-2 were used to estimate surface heat balance in this study. ASTER data is suitable for analyzing heat balance because of the wide spectral range. We used Formosat-2 multispectral data to classify the land surface, which was used to interpolate some surface parameters for estimating heat fluxes. Because of the high spatial resolution of the Formosat-2 image, more roads, open spaces and small vegetation areas could be distinguished from buildings in urban areas; however, misclassifications of land cover in such areas using ASTER data would overestimate the sensible heat flux. On the other hand, the small vegetated areas detected from the Formosat-2 image slightly increased the estimation of latent heat flux. As a result, the storage heat flux derived from Formosat-2 is higher than that derived from ASTER data in most areas. From these results, we can conclude that the higher resolution land coverage map increases accuracy of the heat balance analysis. Storage heat flux occupies about 60 to 80% of the net radiation in most of the artificial surface areas in spite of their usages. Because of the homogeneity of the building roof materials, there is no contrast between the storage heat flux in business and residential areas. In sparsely vegetated urban areas, more heat is stored and latent heat is smaller than that in the forested suburbs. This result implies that density of vegetation has a significant influence in decreasing temperatures. PMID:27873856

Characterizing Temporal and Spatial Changes in Land Surface Temperature across the Amazon Basin using Thermal and Infrared Satellite Data

NASA Astrophysics Data System (ADS)

Cak, A. D.

2017-12-01

The Amazon Basin has faced innumerable pressures in recent years, including logging, mining and resource extraction, agricultural expansion, road building, and urbanization. These changes have drastically altered the landscape, transforming a predominantly forested environment into a mosaic of different types of land cover. The resulting fragmentation has caused dramatic and negative impacts on its structure and function, including on biodiversity and the transfer of water and energy to and from soil, vegetation, and the atmosphere (e.g., evapotranspiration). Because evapotranspiration from forested areas, which is affected by factors including temperature and water availability, plays a significant role in water dynamics in the Amazon Basin, measuring land surface temperature (LST) across the region can provide a dynamic assessment of hydrological, vegetation, and land use and land cover changes. It can also help to identify widespread urban development, which often has a higher LST signal relative to surrounding vegetation. Here, we discuss results from work to measure and identify drivers of change in LST across the entire Amazon Basin through analysis of past and current thermal and infrared satellite imagery. We leverage cloud computing resources in new ways to allow for more efficient analysis of imagery over the Amazon Basin across multiple years and multiple sensors. We also assess potential drivers of change in LST using spatial and multivariate statistical analyses with additional data sources of land cover, urban development, and demographics.

Investigation of Long-Term Impacts of Urbanization when Considering Global Warming for a Coastal Tropical Region

NASA Technical Reports Server (NTRS)

Gonalez, Jorge E.; Comarazamy, Daniel E.; Luvall, Jeffrey C.; Rickman, Douglas L.; Smith, T.

2010-01-01

The overachieving goal of this project is to gain a better understanding of the climate impacts caused by the combined effects of land cover and land use (LCLU) changes and increasing global concentrations of green house gases (GHG) in tropical coastal areas, regions where global, regional and local climate phenomena converge, taking as the test case the densely populated northeast region of the Caribbean island of Puerto Rico. The research uses an integrated approach of high-resolution remote sensing information linked to a high resolution Regional Atmospheric Modeling System (RAMS), which was employed to perform ensembles of climate simulations (combining 2-LCLU and 2-GHG concentration scenarios). Reconstructed agricultural maps are used to define past LCLU, and combined with reconstructed sea surface temperatures (SST) for the same period form the PAST climate scenario (1951-1956); while the PRESENT scenario (2000-2004) was additionally supported by high resolution remote sensing data (10-m-res). The climate reconstruction approach is validated with available observed climate data from surface weather stations for both periods of time simulated. The selection of the past and present climate scenarios considers large-scale biases (i.e. ENSO/NAO) as reflected in the region of interest. Direct and cross comparison of the results is allowing quantifying single, combined, and competitive effects. Results indicate that global GHG have dominant effects on minimum temperatures (following regional tendencies), while urban sprawl dominates maximum temperatures. To further investigate impacts of land use the Bowen Ratio and the thermal response number (TRN) are analyzed. The Bowen ratio indicates that forestation of past agricultural high areas have an overwhelmingly mitigation effect on increasing temperatures observed in different LCLU scenarios, but when abandoned agricultural lands are located in plains, the resulting shrub/grass lands produce higher surface temperatures. The TRN (J/m^2/degC) is a surface property defined as the ratio of the surface net radiation to the rate of change in surface temperature, expresses how those fluxes are reacting to radiant energy inputs. Natural vegetated surfaces have a greater TRN than urban and barren surfaces because the net radiation processed by them is mostly used for latent heat and thermal storage heat rather than sensible heat (heating the air). Significant changes in TRN were observed in the metropolitan area of San Juan for the two analyzed periods reflecting a reduction of this variable in the present from the past consistent with increasing in thermal mass, or intense urbanization.

Evaluation of automated urban surface water extraction from Sentinel-2A imagery using different water indices

NASA Astrophysics Data System (ADS)

Yang, Xiucheng; Chen, Li

2017-04-01

Urban surface water is characterized by complex surface continents and small size of water bodies, and the mapping of urban surface water is currently a challenging task. The moderate-resolution remote sensing satellites provide effective ways of monitoring surface water. This study conducts an exploratory evaluation on the performance of the newly available Sentinel-2A multispectral instrument (MSI) imagery for detecting urban surface water. An automatic framework that integrates pixel-level threshold adjustment and object-oriented segmentation is proposed. Based on the automated workflow, different combinations of visible, near infrared, and short-wave infrared bands in Sentinel-2 image via different water indices are first compared. Results show that object-level modified normalized difference water index (MNDWI with band 11) and automated water extraction index are feasible in urban surface water mapping for Sentinel-2 MSI imagery. Moreover, comparative results are obtained utilizing optimal MNDWI from Sentinel-2 and Landsat 8 images, respectively. Consequently, Sentinel-2 MSI achieves the kappa coefficient of 0.92, compared with that of 0.83 from Landsat 8 operational land imager.

Assessing the Impact of Urbanization on Direct Runoff Using Improved Composite CN Method in a Large Urban Area.

PubMed

Li, Chunlin; Liu, Miao; Hu, Yuanman; Shi, Tuo; Zong, Min; Walter, M Todd

2018-04-17

Urbanization is one of the most widespread anthropogenic activities, which brings a range of physical and biochemical changes to hydrological system and processes. Increasing direct runoff caused by land use change has become a major challenge for urban ecological security. Reliable prediction of the quantity and rate of surface runoff is an inherently difficult and time-consuming task for large ungauged urban areas. In this study, we combined Geographic Information System and remote sensing technology with an improved Soil Conservation Service curve number model to evaluate the effects of land use change on direct runoff volume of the four-ring area in Shenyang, China, and analyzed trends of direct runoff at different scales. Through analyzing trends of direct runoff from 1984 to 2015 at different scales, we explored how urbanization and other potential factors affect direct runoff changes. Total direct runoff volume increased over time, and trends varied from the inner urban area to suburban area. Zones 1 and 2 had a tendency toward decreasing direct runoff volume and risks, while Zones 3 and 4 showed gradual increases at both regional and pixel scales. The most important influence on direct runoff change was urban surface change caused by urbanization. This study presents a framework for identifying hotspots of runoff increase, which can provide important guidance to urban managers in future green infrastructure planning, in the hopes of improving the security of urban water ecological patterns.

Assessing the Impact of Urbanization on Direct Runoff Using Improved Composite CN Method in a Large Urban Area

PubMed Central

Li, Chunlin; Liu, Miao; Hu, Yuanman; Shi, Tuo; Zong, Min; Walter, M. Todd

2018-01-01

Urbanization is one of the most widespread anthropogenic activities, which brings a range of physical and biochemical changes to hydrological system and processes. Increasing direct runoff caused by land use change has become a major challenge for urban ecological security. Reliable prediction of the quantity and rate of surface runoff is an inherently difficult and time-consuming task for large ungauged urban areas. In this study, we combined Geographic Information System and remote sensing technology with an improved Soil Conservation Service curve number model to evaluate the effects of land use change on direct runoff volume of the four-ring area in Shenyang, China, and analyzed trends of direct runoff at different scales. Through analyzing trends of direct runoff from 1984 to 2015 at different scales, we explored how urbanization and other potential factors affect direct runoff changes. Total direct runoff volume increased over time, and trends varied from the inner urban area to suburban area. Zones 1 and 2 had a tendency toward decreasing direct runoff volume and risks, while Zones 3 and 4 showed gradual increases at both regional and pixel scales. The most important influence on direct runoff change was urban surface change caused by urbanization. This study presents a framework for identifying hotspots of runoff increase, which can provide important guidance to urban managers in future green infrastructure planning, in the hopes of improving the security of urban water ecological patterns. PMID:29673182

Spatial temporal analysis of urban heat hazard in Tangerang City

NASA Astrophysics Data System (ADS)

Wibowo, Adi; Kuswantoro; Ardiansyah; Rustanto, Andry; Putut Ash Shidiq, Iqbal

2016-11-01

Urban heat is a natural phenomenon which might caused by human activities. The human activities were represented by various types of land-use such as urban and non-urban area. The aim of this study is to identify the urban heat behavior in Tangerang City as it might threats the urban environment. This study used three types of remote sensing data namely, Landsat TM, Landsat ETM+ and Landsat OLI-TIRS, to capture the urban heat behavior and to analysis the urban heat signature of Tangerang City in 2001, 2012, 2013, 2014, 2015 and 2016. The result showed that urban heat signature change dynamically each month based on the sun radiation. The urban heat island covered only small part of Tangerang City in 2001, but it was significantly increased and reached 50% of the area in 2012. Based on the result on urban heat signature, the threshold for threatening condition is 30 oC which recognized from land surface temperature (LST). The effective temperature (ET) index explains that condition as warm, uncomfortable, increase stress due to sweating and blood flow and may causing cardiovascular disorder.

Understanding Climate Variability of Urban Ecosystems Through the Lens of Citizen Science

NASA Astrophysics Data System (ADS)

Ripplinger, J.; Jenerette, D.; Wang, J.; Chandler, M.; Ge, C.; Koutzoukis, S.

2017-12-01

The Los Angeles megacity is vulnerable to climate warming - a process that locally exacerbates the urban heat island effect as it intensifies with size and density of the built-up area. We know that large-scale drivers play a role, but in order to understand local-scale climate variation, more research is needed on the biophysical and sociocultural processes driving the urban climate system. In this study, we work with citizen scientists to deploy a high-density network of microsensors across a climate gradient to characterize geographic variation in neighborhood meso- and micro-climates. This research asks: How do urbanization, global climate, and vegetation interact across multiple scales to affect local-scale experiences of temperature? Additionally, citizen scientist-led efforts generated research questions focused on examining microclimatic differences among yard groundcover types (rock mulch vs. lawn vs. artificial turf) and also on variation in temperature related to tree cover. Combining sensor measurements with Weather Research and Forecasting (WRF) spatial models and satellite-based temperature, we estimate spatially-explicit maps of land surface temperature and air temperature to illustrate the substantial difference between surface and air urban heat island intensities and the variable degree of coupling between land surface and air temperature in urban areas. Our results show a strong coupling between air temperature variation and landcover for neighborhoods, with significant detectable signatures from tree cover and impervious surface. Temperature covaried most strongly with urbanization intensity at nighttime during peak summer season, when daily mean air temperature ranged from 12.8C to 30.4C across all groundcover types. The combined effects of neighborhood geography and vegetation determine where and how temperature and tree canopy vary within a city. This citizen science-enabled research shows how large-scale climate drivers and urbanization intensity jointly influence the nature and magnitude of coupling between air temperature and tree cover, and demonstrate how urban vegetation provides an important ecosystem service in cities by decreasing the intensity of local urban heat islands.

The Use of the Airborne Thermal/Visible Land Application Sensor (ATLAS) to Determine the Thermal Response Numbers for Urban Areas

NASA Technical Reports Server (NTRS)

Luvall, Jeffrey C.; Rickman, Doug; Quattroch, Dale; Estes. Maury

2007-01-01

Although satellite data are very useful for analysis of the urban heat island effect at a coarse scale, they do not lend themselves to developing a better understanding of which surfaces across the city contribute or drive the development of the urban heat island effect. Analysis of thermal energy responses for specific or discrete surfaces typical of the urban landscape (e.g., asphalt, building rooftops, vegetation) requires measurements at a very fine spatial scale (i.e., < 15m) to adequately resolve these surfaces and their attendant thermal energy regimes. Additionally, very fine scale spatial resolution thermal infrared data, such as that obtained from aircraft, are very useful for demonstrating to planning officials, policy makers, and the general populace the benefits of the urban forest. These benefits include mitigating the urban heat island effect, making cities more aesthetically pleasing and more habitable environments, and aid in overall cooling of the community. High spatial resolution thermal data are required to quantify how artificial surfaces within the city contribute to an increase in urban heating and the benefit of cool surfaces (e.g., surface coatings that reflect much of the incoming solar radiation as opposed to absorbing it thereby lowering urban temperatures). The TRN (thermal response number)(Luvall and Holbo 1989) is a technique using aircraft remotely sensed surface temperatures to quantify the thermal response of urban surfaces. The TRN was used to quantify the thermal response of various urban surface types ranging from completely vegetated surfaces to asphalt and concrete parking lots for several cities in the United States.

Characterizing the fabric of the urban environment: A case studyof Metropolitan Chicago, Illinois and Executive Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akbari, Hashem; Rose, Leanna Shea

2001-10-30

Urban fabric data are needed in order to estimate the impactof light-colored surfaces (roofs and pavements) and urban vegetation(trees, grass, shrubs) on the meteorology and air quality of a city, andto design effective implementation programs. In this report, we discussthe result of a semi-automatic Monte-Carlo statistical approach used todevelop data on surface-type distribution and city-fabric makeup(percentage of various surface-types) using aerial colororthophotography. The digital aerial photographs for metropolitan Chicagocovered a total of about 36 km2 (14 mi2). At 0.3m resolution, there wereapproximately 3.9 x 108 pixels of data. Four major land-use types wereexamined: commercial, industrial, residential, andtransportation/communication. On average, formore » the areas studied, atground level vegetation covers about 29 percent of the area (ranging 4 80percent); roofs cover about 25 percent (ranging 8 41 percent), and pavedsurfaces about 33 percent (ranging 12 59 percent). For the most part,trees shade streets, parking lots, grass, and side-walks. In commercialareas, paved surfaces cover 50 60 percent of the area. In residentialareas, on average, paved surfaces cover about 27percent of the area.Land-use/land-cover (LULC) data from the United States Geological Surveywas used to extrapolate these results from neighborhood scales tometropolitan Chicago. In an area of roughly 2500 km2, defining most ofmetropolitan Chicago, over 53 percent is residential. The total roof areais about 680 km2, and the total paved surfaces (roads, parking areas,sidewalks) are about 880 km2. The total vegetated area is about 680km2.« less

Understanding spatial-temporal urban expansion pattern (1990-2009) using impervious surface data and landscape indexes: a case study in Guangzhou (China)

NASA Astrophysics Data System (ADS)

Fan, Fenglei; Fan, Wei

2014-01-01

A new viewpoint for understanding the urban expansion using impervious surface information, which is obtained using remote sensing imagery is presented. The purpose of this study is to understand and describe the urban expansion pattern with the view of impervious surfaces instead of the conventional view of land use/land cover. Six years' worth of impervious surface data (1990-2009) of Guangzhou are extracted via linear spectral unmixing analysis methods and spatial and temporal characteristics are discussed in detail. The area, density, and gravity centers changes of the impervious surfaces are analyzed to explain internal/external urban expansion. Meanwhile, five landscape indexes, such as patch density, edge density, mean patch size, area-weighted, and fragmentation index, are utilized to describe landscape changes of Guangzhou in past 20 years, which are influenced deeply by the impervious surface expansion. In order to detail landscape changes, two transects corresponding to the two urban expansion directions are designed and five landscape metrics in these two transects are reported. Conclusions can be drawn and shown as following: (1) temporally, the area of impervious surfaces increases from 12,998 to 59,911 ha from 1990 to 2009. The amount of impervious surface varies in different periods. The annual growth rates of impervious surface area during 1990-1995, 1995-1998, and 1998-2000 are 10.16%, 11.61%, and 10.78%, respectively; (2) annual growth rates decrease from 10.78% (1998-2000) to 5.67% (2000-2003). Nevertheless, from 2003-2009, the annual growth rate has a slight increase compared to a former period. The rate is 5.91% (3) spatially, gravity centers of medium and high percentage impervious surfaces migrate slightly; and (4) according to the gradient analysis in the two transects, it can be observed that the high percentage of impervious surface increases gradually in new city districts (from west to east and from south to north).

Analysis and modelling of surface Urban Heat Island in 20 Canadian cities under climate and land-cover change.

PubMed

Gaur, Abhishek; Eichenbaum, Markus Kalev; Simonovic, Slobodan P

2018-01-15

Surface Urban Heat Island (SUHI) is an urban climate phenomenon that is expected to respond to future climate and land-use land-cover change. It is important to further our understanding of physical mechanisms that govern SUHI phenomenon to enhance our ability to model future SUHI characteristics under changing geophysical conditions. In this study, SUHI phenomenon is quantified and modelled at 20 cities distributed across Canada. By analyzing MODerate Resolution Imaging Spectroradiometer (MODIS) sensed surface temperature at the cities over 2002-2012, it is found that 16 out of 20 selected cities have experienced a positive SUHI phenomenon while 4 cities located in the prairies region and high elevation locations have experienced a negative SUHI phenomenon in the past. A statistically significant relationship between observed SUHI magnitude and city elevation is also recorded over the observational period. A Physical Scaling downscaling model is then validated and used to downscale future surface temperature projections from 3 GCMs and 2 extreme Representative Concentration Pathways in the urban and rural areas of the cities. Future changes in SUHI magnitudes between historical (2006-2015) and future timelines: 2030s (2026-2035), 2050s (2046-2055), and 2090s (2091-2100) are estimated. Analysis of future projected changes indicate that 15 (13) out of 20 cities can be expected to experience increases in SUHI magnitudes in future under RCP 2.6 (RCP 8.5). A statistically significant relationship between projected future SUHI change and current size of the cities is also obtained. The study highlights the role of city properties (i.e. its size, elevation, and surrounding land-cover) towards shaping their current and future SUHI characteristics. The results from this analysis will help decision-makers to manage Canadian cities more efficiently under rapidly changing geophysical and demographical conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Converting Paddy Rice Field to Urban Use Dramatically Altered the Water and Energy Balances in Southern China

NASA Astrophysics Data System (ADS)

Hao, L.; Sun, G.; Liu, Y.; Qin, M.; Huang, X.; Fang, D.

2017-12-01

Paddy rice wetlands are the main land use type across southern China, which impact the regional environments by affecting evapotranspiration (ET) and other water and energy related processes. Our study focuses on the effects of land-cover change on water and energy processes in the Qinhuai River Basin, a typical subtropical humid region that is under rapid ecological and economical transformations. This study integrates multiple methods and techniques including remote sensing, water and energy balance model (i.e., Surface Energy Balance Algorithm for Land, SEBAL), ecohydrological model (i.e., Soil and Water Assessment Tool, SWAT), and ground observation (Eddy Covariance measurement, etc.). We found that conversion of paddy rice field to urban use led to rise in vapor pressure deficit (VPD) and reduction in ET, and thus resulted in changes in local and regional water and heat balance. The effects of the land-use change on ET and VPD overwhelmed the effects of regional climate warming and climate variability. We conclude that the ongoing large-scale urbanization of the rice paddy-dominated regions in humid southern China and East Asia will likely exacerbate environmental consequences (e.g., elevated storm-flow volume, aggravated flood risks, and intensified urban heat island and urban dry island effects). The potential role of vegetated land cover in moderating water and energy balances and maintaining a stable climate should be considered in massive urban planning and global change impact assessment in southern China.

Radiative Forcing and Temperature Response to Changes in Urban Albedos and Associated CO2 Offsets

NASA Technical Reports Server (NTRS)

Menon, Surabi; Akbari, Hashem; Mahanama, Sarith; Sednev, Igor; Levinson, Ronnen

2009-01-01

The two main forcings that can counteract to some extent the positive forcings from greenhouse gases from pre-industrial times to present-day are the aerosol and related aerosol-cloud forcings, and the radiative response to changes in surface albedo. Here, we quantify the change in radiative forcing and surface temperature that may be obtained by increasing the albedos of roofs and pavements in urban areas in temperate and tropical regions of the globe. Using the catchment land surface model (the land model coupled to the GEOS-5 Atmospheric General Circulation Model), we quantify the response of the total outgoing (outgoing shortwave+longwave) radiation to urban albedo changes. Globally, the total outgoing radiation increased by 0.5 W/square m and temperature decreased by -0.008 K for an average 0.003 increase in albedo. For the U.S. the total outgoing total radiation increased by 2.3 W/square meter, and temperature decreased by approximately 0.03 K for an average 0.01 increase in albedo. These values are for the boreal summer (Tune-July-August). Based on these forcings, the expected emitted CO2 offset for a plausible 0.25 and 0.15 increase in albedos of roofs and pavements, respectively, for all global urban areas, was found to be approximately 57 Gt CO2 . A more meaningful evaluation of the impacts of urban albedo increases on climate and the expected CO2 offsets would require simulations which better characterizes urban surfaces and represents the full annual cycle.

Landscaping practices, land use patterns and stormwater quantity and quality in urban watersheds

NASA Astrophysics Data System (ADS)

Miles, B.; Band, L. E.

2011-12-01

Increasing quantity and decreasing quality of urban stormwater threatens biodiversity in local streams and reservoirs, jeopardizes water supplies, and ultimately contributes to estuarine eutrophication. To estimate the effects that present and alternative landscaping practices and land use patterns may have on urban stormwater quantity and quality, simulations of existing land use/land cover using the Regional Hydro-Ecologic Simulation System (RHESSys), a process-based surface hydrology and biogeochemistry model, were developed for watersheds in Baltimore, MD (as part of the Baltimore Ecosystem Study (BES) NSF Long-Term Ecological Research (LTER) site) and Durham, NC (as part of the NSF Urban Long-Term Research Area (ULTRA) program). The influence of land use patterns and landscaping practices on nutrient export in urban watersheds has been explored as part of the BES; this work has focused on improving our understanding of how residential landscaping practices (i.e. lawn fertilization rates) vary across land use and socioeconomic gradients. Elsewhere, others have explored the political ecology of residential landscaping practices - seeking to understand the economic, political, and cultural influences on the practice of high-input residential turf-grass management. Going forward, my research will synthesize and extend this prior work. Rather than pre-supposing predominant residential land use patterns and landscaping practices (i.e. lower-density periphery development incorporating high-input turf landscapes) alternate land use and landscaping scenarios (e.g. higher-density/transit-oriented development, rain gardens, vegetable gardens, native plant/xeriscaping) will be developed through interviews/focus groups with stakeholders (citizens, public officials, developers, non-profits). These scenarios will then be applied to the RHESSys models already developed for catchments in Baltimore and Durham. The modeled scenario results will be used to identify alternate land use patterns and landscaping practices that would: (1) help to reduce non-point sources of nutrient pollution in urban watersheds; and (2) be likely to gain public support. This research will inform sustainable development policy while furthering interdisciplinary research in the fields of planning and water resource management.

Relationships between urbanization and the oak resource of the Minneapolis/St. Paul metropolitan area from 1991 to 1998

Treesearch

Kathryn Kromroy; Kathleen Ward; Paul Castillo; Jennifer Juzwik

2006-01-01

Urbanization was associated with loss and transformation of the oak forest in the Twin Cities (Minneapolis and St. Paul) metropolitan area (TCMA) over a recent 7-year interval. Between 1991 and 1998, urbanization increased based on several indicators: population density, area of developed land, and area of impervious surface?total impervious area and area within three...

Quantifying the Impact of Land Cover Composition on Intra-Urban Air Temperature Variations at a Mid-Latitude City

PubMed Central

Yan, Hai; Fan, Shuxin; Guo, Chenxiao; Hu, Jie; Dong, Li

2014-01-01

The effects of land cover on urban-rural and intra-urban temperature differences have been extensively documented. However, few studies have quantitatively related air temperature to land cover composition at a local scale which may be useful to guide landscape planning and design. In this study, the quantitative relationships between air temperature and land cover composition at a neighborhood scale in Beijing were investigated through a field measurement campaign and statistical analysis. The results showed that the air temperature had a significant positive correlation with the coverage of man-made surfaces, but the degree of correlation varied among different times and seasons. The different land cover types had different effects on air temperature, and also had very different spatial extent dependence: with increasing buffer zone size (from 20 to 300 m in radius), the correlation coefficient of different land cover types varied differently, and their relative impacts also varied among different times and seasons. At noon in summer, ∼37% of the variations in temperature were explained by the percentage tree cover, while ∼87% of the variations in temperature were explained by the percentage of building area and the percentage tree cover on summer night. The results emphasize the key role of tree cover in attenuating urban air temperature during daytime and nighttime in summer, further highlighting that increasing vegetation cover could be one effective way to ameliorate the urban thermal environment. PMID:25010134

Urban Growth Detection Using Filtered Landsat Dense Time Trajectory in an Arid City

NASA Astrophysics Data System (ADS)

Ye, Z.; Schneider, A.

2014-12-01

Among all remote sensing environment monitoring techniques, time series analysis of biophysical index is drawing increasing attention. Although many of them studied forest disturbance and land cover change detection, few focused on urban growth mapping at medium spatial resolution. As Landsat archive becomes open accessible, methods using Landsat time-series imagery to detect urban growth is possible. It is found that a time trajectory from a newly developed urban area shows a dramatic drop of vegetation index. This enable the utilization of time trajectory analysis to distinguish impervious surface and crop land that has a different temporal biophysical pattern. Also, the time of change can be estimated, yet many challenges remain. Landsat data has lower temporal resolution, which may be worse when cloud-contaminated pixels and SLC-off effect exist. It is difficult to tease apart intra-annual, inter-annual, and land cover difference in a time series. Here, several methods of time trajectory analysis are utilized and compared to find a computationally efficient and accurate way on urban growth detection. A case study city, Ankara, Turkey is chosen for its arid climate and various landscape distributions. For preliminary research, Landsat TM and ETM+ scenes from 1998 to 2002 are chosen. NDVI, EVI, and SAVI are selected as research biophysical indices. The procedure starts with a seasonality filtering. Only areas with seasonality need to be filtered so as to decompose seasonality and extract overall trend. Harmonic transform, wavelet transform, and a pre-defined bell shape filter are used to estimate the overall trend in the time trajectory for each pixel. The point with significant drop in the trajectory is tagged as change point. After an urban change is detected, forward and backward checking is undertaken to make sure it is really new urban expansion other than short time crop fallow or forest disturbance. The method proposed here can capture most of the urban growth during research time period, although the accuracy of time point determination is a bit lower than this. Results from several biophysical indices and filtering methods are similar. Some fallows and bare lands in arid area are easily confused with urban impervious surface.

Implication of relationship between natural impacts and land use/land cover (LULC) changes of urban area in Mongolia

NASA Astrophysics Data System (ADS)

Gantumur, Byambakhuu; Wu, Falin; Zhao, Yan; Vandansambuu, Battsengel; Dalaibaatar, Enkhjargal; Itiritiphan, Fareda; Shaimurat, Dauryenbyek

2017-10-01

Urban growth can profoundly alter the urban landscape structure, ecosystem processes, and local climates. Timely and accurate information on the status and trends of urban ecosystems is critical to develop strategies for sustainable development and to improve the urban residential environment and living quality. Ulaanbaatar city was urbanized very rapidly caused by herders and farmers, many of them migrating from rural places, have played a big role in this urban expansion (sprawl). Today, 1.3 million residents for about 40% of total population are living in the Ulaanbaatar region. Those human activities influenced stronger to green environments. Therefore, the aim of this study is determined to change detection of land use/land cover (LULC) and estimating their areas for the trend of future by remote sensing and statistical methods. The implications of analysis were provided by change detection methods of LULC, remote sensing spectral indices including normalized difference vegetation index (NDVI), normalized difference water index (NDWI) and normalized difference built-up index (NDBI). In addition, it can relate to urban heat island (UHI) provided by Land surface temperature (LST) with local climate issues. Statistical methods for image processing used to define relations between those spectral indices and change detection images and regression analysis for time series trend in future. Remote sensing data are used by Landsat (TM/ETM+/OLI) satellite images over the period between 1990 and 2016 by 5 years. The advantages of this study are very useful remote sensing approaches with statistical analysis and important to detecting changes of LULC. The experimental results show that the LULC changes can image on the present and after few years and determined relations between impacts of environmental conditions.

The Atlanta Urban Heat Island Mitigation and Air Quality Modeling Project: How High-Resoution Remote Sensing Data Can Improve Air Quality Models

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Estes, Maurice G., Jr.; Crosson, William L.; Khan, Maudood N.

2006-01-01

The Atlanta Urban Heat Island and Air Quality Project had its genesis in Project ATLANTA (ATlanta Land use Analysis: Temperature and Air quality) that began in 1996. Project ATLANTA examined how high-spatial resolution thermal remote sensing data could be used to derive better measurements of the Urban Heat Island effect over Atlanta. We have explored how these thermal remote sensing, as well as other imaged datasets, can be used to better characterize the urban landscape for improved air quality modeling over the Atlanta area. For the air quality modeling project, the National Land Cover Dataset and the local scale Landpro99 dataset at 30m spatial resolutions have been used to derive land use/land cover characteristics for input into the MM5 mesoscale meteorological model that is one of the foundations for the Community Multiscale Air Quality (CMAQ) model to assess how these data can improve output from CMAQ. Additionally, land use changes to 2030 have been predicted using a Spatial Growth Model (SGM). SGM simulates growth around a region using population, employment and travel demand forecasts. Air quality modeling simulations were conducted using both current and future land cover. Meteorological modeling simulations indicate a 0.5 C increase in daily maximum air temperatures by 2030. Air quality modeling simulations show substantial differences in relative contributions of individual atmospheric pollutant constituents as a result of land cover change. Enhanced boundary layer mixing over the city tends to offset the increase in ozone concentration expected due to higher surface temperatures as a result of urbanization.

Assessments of urban growth in the Tampa Bay watershed using remote sensing data

USGS Publications Warehouse

Xian, G.; Crane, M.

2005-01-01

Urban development has expanded rapidly in the Tampa Bay area of west-central Florida over the past century. A major effect associated with this population trend is transformation of the landscape from natural cover types to increasingly impervious urban land. This research utilizes an innovative approach for mapping urban extent and its changes through determining impervious surfaces from Landsat satellite remote sensing data. By 2002, areas with subpixel impervious surface greater than 10% accounted for approximately 1800 km2, or 27 percent of the total watershed area. The impervious surface area increases approximately three-fold from 1991 to 2002. The resulting imperviousness data are used with a defined suite of geospatial data sets to simulate historical urban development and predict future urban and suburban extent, density, and growth patterns using SLEUTH model. Also examined is the increasingly important influence that urbanization and its associated imperviousness extent have on the individual drainage basins of the Tampa Bay watershed.

A spatially distributed model for assessment of the effects of changing land use and climate on urban stream quality: Development of a Spatially Distributed Urban Water Quality Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Ning; Yearsley, John; Baptiste, Marisa

While the effects of land use change in urban areas have been widely examined, the combined effects of climate and land use change on the quality of urban and urbanizing streams have received much less attention. We describe a modeling framework that is applicable to the evaluation of potential changes in urban water quality and associated hydrologic changes in response to ongoing climate and landscape alteration. The grid-based spatially distributed model, DHSVM-WQ, is an outgrowth of the Distributed Hydrology-Soil-Vegetation Model (DHSVM) that incorporates modules for assessing hydrology and water quality in urbanized watersheds at a high spatial and temporal resolution.more » DHSVM-WQ simulates surface runoff quality and in-stream processes that control the transport of nonpoint-source (NPS) pollutants into urban streams. We configure DHSVM-WQ for three partially urbanized catchments in the Puget Sound region to evaluate the water quality responses to current conditions and projected changes in climate and/or land use over the next century. Here we focus on total suspended solids (TSS) and total phosphorus (TP) from nonpoint sources (runoff), as well as stream temperature. The projection of future land use is characterized by a combination of densification in existing urban or partially urban areas, and expansion of the urban footprint. The climate change scenarios consist of individual and concurrent changes in temperature and precipitation. Future precipitation is projected to increase in winter and decrease in summer, while future temperature is projected to increase throughout the year. Our results show that urbanization has a much greater effect than climate change on both the magnitude and seasonal variability of streamflow, TSS and TP loads largely due to substantially increased streamflow, and particularly winter flow peaks. Water temperature is more sensitive to climate warming scenarios than to urbanization and precipitation changes. Future urbanization and climate change together are predicted to significantly increase annual mean streamflow (up to 55%), water temperature (up to 1.9 ºC), TSS load (up to 182%), and TP load (up to 74%).« less

A zone-based approach to identifying urban land uses using nationally-available data

NASA Astrophysics Data System (ADS)

Falcone, James A.

Accurate identification of urban land use is essential for many applications in environmental study, ecological assessment, and urban planning, among other fields. However, because physical surfaces of land cover types are not necessarily related to their use and economic function, differentiating among thematically-detailed urban land uses (single-family residential, multi-family residential, commercial, industrial, etc.) using remotely-sensed imagery is a challenging task, particularly over large areas. Because the process requires an interpretation of tone/color, size, shape, pattern, and neighborhood association elements within a scene, it has traditionally been accomplished via manual interpretation of aerial photography or high-resolution satellite imagery. Although success has been achieved for localized areas using various automated techniques based on high-spatial or high-spectral resolution data, few detailed (Anderson Level II equivalent or greater) urban land use mapping products have successfully been created via automated means for broad (multi-county or larger) areas, and no such product exists today for the United States. In this study I argue that by employing a zone-based approach it is feasible to map thematically-detailed urban land use classes over large areas using appropriate combinations of non-image based predictor data which are nationally and publicly available. The approach presented here uses U.S. Census block groups as the basic unit of geography, and predicts the percent of each of ten land use types---nine of them urban---for each block group based on a number of data sources, to include census data, nationally-available point locations of features from the USGS Geographic Names Information System, historical land cover, and metrics which characterize spatial pattern, context (e.g. distance to city centers or other features), and measures of spatial autocorrelation. The method was demonstrated over a four-county area surrounding the city of Boston. A generalized version of the method (six land use classes) was also developed and cross-validated among additional geographic settings: Atlanta, Los Angeles, and Providence. The results suggest that even with the thematically-detailed ten-class structure, it is feasible to map most urban land uses with reasonable accuracy at the block group scale, and results improve with class aggregation. When classified by predicted majority land use, 79% of block groups correctly matched the actual majority land use with the ten-class models. Six-class models typically performed well for the geographic area they were developed from, however models had mixed performance when transported to other geographic settings. Contextual variables, which characterized a block group's spatial relationship to city centers, transportation routes, and other amenities, were consistently strong predictors of most land uses, a result which corresponds to classic urban land use theory. The method and metrics derived here provide a prototype for mapping urban land uses from readily-available data over broader geographic areas than is generally practiced today using current image-based solutions.

Influences of land cover types, meteorological conditions, anthropogenic heat and urban area on surface urban heat island in the Yangtze River Delta Urban Agglomeration.

PubMed

Du, Hongyu; Wang, Duoduo; Wang, Yuanyuan; Zhao, Xiaolei; Qin, Fei; Jiang, Hong; Cai, Yongli

2016-11-15

Urban heat islands (UHIs) reflect the localized impact of human activities on thermal fields. In this study, we assessed the surface UHI and its relationship with types of land, meteorological conditions, anthropogenic heat sources and urban areas in the Yangtze River Delta Urban Agglomeration (YRDUA) with the aid of remote sensing data, statistical data and meteorological data. The results showed that the UHI intensity in YRDUA was the strongest (0.84°C) in summer, followed by 0.81°C in autumn, 0.78°C in spring and 0.53°C in winter. The daytime UHI intensity is 0.98°C, which is higher than the nighttime UHI intensity of 0.50°C. Then, the relationship between the UHI intensity and several factors such as meteorological conditions, anthropogenic heat sources and the urban area were analysed. The results indicated that there was an insignificant correlation between population density and the UHI intensity. Energy consumption, average temperature and urban area had a significant positive correlation with UHI intensity. However, the average wind speed and average precipitation were significantly negatively correlated with UHI intensity. This study provides insight into the regional climate characteristics and a scientific basis for city layout. Copyright © 2016 Elsevier B.V. All rights reserved.

Do Surface Energy Fluxes Reveal Land Use/Land Cover Change in South Florida?: A Remote Sensing Perspective

NASA Astrophysics Data System (ADS)

Kandel, H. P.; Melesse, A. M.

2017-12-01

Series of changes on land use/ land cover in South Florida resulting from drainage and development activities during early to mid-20th followed by restoration measures since late-20th century have had prominent impacts on hydrologic regime and energy fluxes in the region. Previous results from numerical modeling and MODIS-based analysis have shown a shift in dominance of heat fluxes: from latent to sensible along the axes of urbanization, and an opposite along the axes of restoration. This study implements a slightly modified version of surface energy balance algorithm (SEBAL) on cloud-masked Landsat imageries archived over the period of 30-years combined with ground-meteorological data for South Florida using spatial analysis model in ArcGIS and calculates energy flux components: sensible heat flux, latent heat flux, and ground heat flux. The study finally computes variation of Bowen's ratio (BR) and daily evapotranspiration (ET) rate over various land covers for different years. Coexistences are apparent between increased BR and increased intensity of urbanization, and between increased daily ET rates and improved best management practices in agricultural areas. An increase in mean urban BR from 1.67 in 1984 to 3.06 in 2010 show plausible link of BR with urban encroachment of open lands, and expulsion of additional heat by increased population/automobiles/factories/air conditioning units. Likewise, increase in mean agricultural daily ET rates from 0.21 mm/day to 3.60 mm/day between 1984 to 2010 probably shows the effects of improved moisture conditions on the northern farm lands as the results of restoration practices. Once new observed data become available to corroborate these results, remote sensing methods-owing to their greater spatial and temporal details-can be used as assessment measures both for the progress of restoration evaluation and for the extent detection of human-induced climate change.

Analyzing the Relative Linkages of Land Use and Hydrologic Variables with Urban Surface Water Quality using Multivariate Techniques

NASA Astrophysics Data System (ADS)

Ahmed, S.; Abdul-Aziz, O. I.

2015-12-01

We used a systematic data-analytics approach to analyze and quantify relative linkages of four stream water quality indicators (total nitrogen, TN; total phosphorus, TP; chlorophyll-a, Chla; and dissolved oxygen, DO) with six land use and four hydrologic variables, along with the potential external (upstream in-land and downstream coastal) controls in highly complex coastal urban watersheds of southeast Florida, U.S.A. Multivariate pattern recognition techniques of principle component and factor analyses, in concert with Pearson correlation analysis, were applied to map interrelations and identify latent patterns of the participatory variables. Relative linkages of the in-stream water quality variables with their associated drivers were then quantified by developing dimensionless partial least squares (PLS) regression model based on standardized data. Model fitting efficiency (R2=0.71-0.87) and accuracy (ratio of root-mean-square error to the standard deviation of the observations, RSR=0.35-0.53) suggested good predictions of the water quality variables in both wet and dry seasons. Agricultural land and groundwater exhibited substantial controls on surface water quality. In-stream TN concentration appeared to be mostly contributed by the upstream water entering from Everglades in both wet and dry seasons. In contrast, watershed land uses had stronger linkages with TP and Chla than that of the watershed hydrologic and upstream (Everglades) components for both seasons. Both land use and hydrologic components showed strong linkages with DO in wet season; however, the land use linkage appeared to be less in dry season. The data-analytics method provided a comprehensive empirical framework to achieve crucial mechanistic insights into the urban stream water quality processes. Our study quantitatively identified dominant drivers of water quality, indicating key management targets to maintain healthy stream ecosystems in complex urban-natural environments near the coast.

Effects of land use change and water reuse options on urban water cycle.

PubMed

Lee, Jiho; Pak, Gijung; Yoo, Chulsang; Kim, Sangdan; Yoon, Jaeyoung

2010-01-01

The aim of this article was to study the effects of land use change and water reuse options on an urban water cycle. A water cycle analysis was performed on the Goonja drainage basin, located in metropolitan Seoul, using the Aquacycle model. The chronological effects of urbanization were first assessed for the land uses of the Goonja drainage basin from 1975 to 2005, where the ratio of impervious areas ranged from 43% to 84%. Progressive urbanization was identified as leading to a decrease in evapotranspiration (29%), an increase in surface runoff (41%) and a decrease in groundwater recharge (74%), indicating a serious distortion of the water cycle. From a subsequent analysis of the water reuse options, such as rainwater use and wastewater reuse, it is concluded that wastewater reuse seemed to have an advantage over rainwater use for providing a consistent water supply throughout the year for a country like Korea, where the rainy season is concentrated during the summer monsoon.

Characterizing the fabric of the urban environment: A case study of Salt Lake City, Utah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akbari, Hashem; Rose, L. Shea

2001-02-28

Urban fabric data are needed in order to estimate the impact of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on the meteorology and air quality of a city, and to design effective implementation programs. In this report, we discuss the result of a semi-automatic Monte-Carlo statistical approach used to develop data on surface-type distribution and city-fabric makeup (percentage of various surface-types) using aerial color orthophotography. The digital aerial photographs for Salt Lake City covered a total of about 34 km2 (13 mi2). At 0.50-m resolution, there were approximately 1.4 x 108 pixels of data. Four majormore » land-use types were examined: (1) commercial, (2) industrial, (3) educational, and (4) residential. On average, for the areas studied, vegetation covers about 46 percent of the area (ranging 44-51 percent), roofs cover about 21 percent (ranging 15-24 percent), and paved surfaces about 26 percent (ranging 21-28 percent). For the most part, trees shade streets, parking lots, grass, and sidewalks. In most non-residential areas, paved surfaces cover 46-66 percent of the area. In residential areas, on average, paved surfaces cover about 32 percent of the area. Land-use/land-cover (LU/LC) data from the United States Geological Survey were used to extrapolate these results from neighborhood scales to metropolitan Salt Lake City. In an area of roughly 560 km2, defining most of metropolitan Salt Lake City, over 60 percent is residential. The total roof area is about 110 km2, and the total paved surface area (roads, parking areas, sidewalks) covers about 170 km2. The total vegetated area covers about 230 km2.« less

Supplementary data of “Impacts of mesic and xeric urban vegetation on outdoor thermal comfort and microclimate in Phoenix, AZ”

PubMed Central

Song, Jiyun; Wang, Zhi-Hua

2015-01-01

An advanced Markov-Chain Monte Carlo approach called Subset Simulation is described in Au and Beck (2001) [1] was used to quantify parameter uncertainty and model sensitivity of the urban land-atmospheric framework, viz. the coupled urban canopy model-single column model (UCM-SCM). The results show that the atmospheric dynamics are sensitive to land surface conditions. The most sensitive parameters are dimensional parameters, i.e. roof width, aspect ratio, roughness length of heat and momentum, since these parameters control the magnitude of sensible heat flux. The relative insensitive parameters are hydrological parameters since the lawns or green roofs in urban areas are regularly irrigated so that the water availability for evaporation is never constrained. PMID:26702421

Green Infrastructure and Watershed-Scale Hydrology in Mixed Land Cover System

EPA Science Inventory

Urbanization results in replacement of pervious areas (e.g., vegetation, topsoil) with impervious surfaces such as roads, roofs, and parking lots, which cause reductions in interception, evapotranspiration, and infiltration, and increases in surface runoff (overland flow) and pol...

Land Use and Land Cover (LULC) Change Detection in Islamabad and its Comparison with Capital Development Authority (CDA) 2006 Master Plan

NASA Astrophysics Data System (ADS)

Hasaan, Zahra

2016-07-01

Remote sensing is very useful for the production of land use and land cover statistics which can be beneficial to determine the distribution of land uses. Using remote sensing techniques to develop land use classification mapping is a convenient and detailed way to improve the selection of areas designed to agricultural, urban and/or industrial areas of a region. In Islamabad city and surrounding the land use has been changing, every day new developments (urban, industrial, commercial and agricultural) are emerging leading to decrease in vegetation cover. The purpose of this work was to develop the land use of Islamabad and its surrounding area that is an important natural resource. For this work the eCognition Developer 64 computer software was used to develop a land use classification using SPOT 5 image of year 2012. For image processing object-based classification technique was used and important land use features i.e. Vegetation cover, barren land, impervious surface, built up area and water bodies were extracted on the basis of object variation and compared the results with the CDA Master Plan. The great increase was found in built-up area and impervious surface area. On the other hand vegetation cover and barren area followed a declining trend. Accuracy assessment of classification yielded 92% accuracies of the final land cover land use maps. In addition these improved land cover/land use maps which are produced by remote sensing technique of class definition, meet the growing need of legend standardization.

Improving surface-subsurface water budgeting using high resolution satellite imagery applied on a brownfield.

PubMed

Dujardin, J; Batelaan, O; Canters, F; Boel, S; Anibas, C; Bronders, J

2011-01-15

The estimation of surface-subsurface water interactions is complex and highly variable in space and time. It is even more complex when it has to be estimated in urban areas, because of the complex patterns of the land-cover in these areas. In this research a modeling approach with integrated remote sensing analysis has been developed for estimating water fluxes in urban environments. The methodology was developed with the aim to simulate fluxes of contaminants from polluted sites. Groundwater pollution in urban environments is linked to patterns of land use and hence it is essential to characterize the land cover in a detail. An object-oriented classification approach applied on high-resolution satellite data has been adopted. To assign the image objects to one of the land-cover classes a multiple layer perceptron approach was adopted (Kappa of 0.86). Groundwater recharge has been simulated using the spatially distributed WetSpass model and the subsurface water flow using MODFLOW in order to identify and budget water fluxes. The developed methodology is applied to a brownfield case site in Vilvoorde, Brussels (Belgium). The obtained land use map has a strong impact on the groundwater recharge, resulting in a high spatial variability. Simulated groundwater fluxes from brownfield to the receiving River Zenne were independently verified by measurements and simulation of groundwater-surface water interaction based on thermal gradients in the river bed. It is concluded that in order to better quantify total fluxes of contaminants from brownfields in the groundwater, remote sensing imagery can be operationally integrated in a modeling procedure. Copyright © 2010 Elsevier B.V. All rights reserved.

Connecting Water Quality With Air Quality Through Microbial Aerosols

NASA Astrophysics Data System (ADS)

Dueker, M. Elias

Aerosol production from surface waters results in the transfer of aquatic materials (including nutrients and bacteria) to air. These materials can then be transported by onshore winds to land, representing a biogeochemical connection between aquatic and terrestrial systems not normally considered. In urban waterfront environments, this transfer could result in emissions of pathogenic bacteria from contaminated waters. Despite the potential importance of this link, sources, near-shore deposition, identity and viability of microbial aerosols are largely uncharacterized. This dissertation focuses on the environmental and biological mechanisms that define this water-air connection, as a means to build our understanding of the biogeochemical, biogeographical, and public health implications of the transfer of surface water materials to the near-shore environment in both urban and non-urban environments. The effects of tidal height, wind speed and fog on coastal aerosols and microbial content were first quantified on a non-urban coast of Maine, USA. Culture-based, culture-independent, and molecular methods were used to simultaneously sample microbial aerosols while monitoring meteorological parameters. Aerosols at this site displayed clear marine influence and high concentrations of ecologically-relevant nutrients. Coarse aerosol concentrations significantly increased with tidal height, onshore wind speed, and fog presence. Tidal height and fog presence did not significantly influence total microbial aerosol concentrations, but did have a significant effect on culturable microbial aerosol fallout. Molecular analyses of the microbes settling out of near-shore aerosols provided further evidence of local ocean to terrestrial transport of microbes. Aerosol and surface ocean bacterial communities shared species and in general were dominated by organisms previously sampled in marine environments. Fog presence strengthened the microbial connection between water and land through air by increasing microbial aerosol settling rates and enhancing viability of aerosolized marine microbes. Using methods developed for the non-urban site, the role of local environment and winds in mediating water-air connections was further investigated in the urban environment. The local environment, including water surfaces, was an important source of microbial aerosols at urban sites. Large portions of the urban waterfront microbial aerosol communities were aquatic and, at a highly polluted Superfund waterfront, were closely related to bacteria previously described in environments contaminated with hydrocarbons, heavy metals, sewage and other industrial waste. Culturable urban aerosols and surface waters contained bacterial genera known to include human pathogens and asthma agents. High onshore winds strengthened this water-air connection by playing both a transport and production role. The microbial connection between water and air quality outlined by this dissertation highlights the need for information on the mechanisms that deliver surface water materials to terrestrial systems on a much larger scale. Moving from point measurements to landscape-level analyses will allow for the quantitative assessment of implications for this microbial water-air-land transfer in both urban and non-urban arenas.

Influence of urban land cover changes and climate change for the exposure of European cities to flooding during high-intensity precipitation

NASA Astrophysics Data System (ADS)

Skougaard Kaspersen, P.; Høegh Ravn, N.; Arnbjerg-Nielsen, K.; Madsen, H.; Drews, M.

2015-06-01

The extent and location of impervious surfaces within urban areas due to past and present city development strongly affects the amount and velocity of run-off during high-intensity rainfall and consequently influences the exposure of cities towards flooding. The frequency and intensity of extreme rainfall are expected to increase in many places due to climate change and thus further exacerbate the risk of pluvial flooding. This paper presents a combined hydrological-hydrodynamic modelling and remote sensing approach suitable for examining the susceptibility of European cities to pluvial flooding owing to recent changes in urban land cover, under present and future climatic conditions. Estimated changes in impervious urban surfaces based on Landsat satellite imagery covering the period 1984-2014 are combined with regionally downscaled estimates of current and expected future rainfall extremes to enable 2-D overland flow simulations and flood hazard assessments. The methodology is evaluated for the Danish city of Odense. Results suggest that the past 30 years of urban development alone has increased the city's exposure to pluvial flooding by 6% for 10-year rainfall up to 26% for 100-year rainfall. Corresponding estimates for RCP4.5 and RCP8.5 climate change scenarios (2071-2100) are in the order of 40 and 100%, indicating that land cover changes within cities can play a central role for the cities' exposure to flooding and conversely also for their adaptation to a changed climate.

Quantifying Water and Energy Fluxes Over Different Urban Land Covers in Phoenix, Arizona

NASA Astrophysics Data System (ADS)

Templeton, Nicole P.; Vivoni, Enrique R.; Wang, Zhi-Hua; Schreiner-McGraw, Adam P.

2018-02-01

The impact of urbanization on water and energy fluxes varies according to the characteristics of the urban patch type. Nevertheless, urban flux observations are limited, particularly in arid climates, given the wide variety of land cover present in cities. To help address this need, a mobile eddy covariance tower was deployed at three locations in Phoenix, Arizona, to sample the surface energy balance at a parking lot, a xeric landscaping (irrigated trees with gravel) and a mesic landscaping (irrigated turf grass). These deployments were compared to a stationary eddy covariance tower in a suburban neighborhood. A comparison of the observations revealed key differences between the mobile and reference sites tied to the urban land cover within the measurement footprints. For instance, the net radiation varied substantially among the sites in manners consistent with albedo and shallow soil temperature differences. The partitioning of available energy between sensible and latent heat fluxes was modulated strongly by the presence of outdoor water use, with the irrigated turf grass exhibiting the highest evaporative fraction. At this site, we identified a lack of sensitivity of turbulent flux partitioning to precipitation events, which suggests that frequent outdoor water use removes water limitations in an arid climate, thus leading to mesic conditions. Other urban land covers with less irrigation, however, exhibited sensitivity to the occurrence of precipitation, as expected for an arid climate. As a result, quantifying the frequency and magnitude of outdoor water use is critical for understanding evapotranspiration losses in arid urban areas.

Polycyclic aromatic hydrocarbons in urban soils of different land uses in Beijing, China: distribution, sources and their correlation with the city's urbanization history.

PubMed

Liu, Shaoda; Xia, Xinghui; Yang, Lingyan; Shen, Mohai; Liu, Ruimin

2010-05-15

A total of 127 surface soil samples (0-20 cm) were collected from Beijing's urban district and determined for 16 polycyclic aromatic hydrocarbons (PAHs). The mean concentration of summation SigmaPAHs was 1802.6 ng g(-1) with a standard deviation of 1824.2 ng g(-1). Average summation SigmaPAHs concentration and the percentage of high-molecular weight PAHs (4-6-rings) decreased from inner city to exterior areas. This correlated with the urbanization history of Beijing's urban district and inferred an increasing trend of soil PAHs with accumulation time and age of the urban area. summation SigmaPAHs in different land uses decreased in an order as: culture and education area (CEA)>classical garden (CG), business area (BA)>residential area (RA), roadside area (RSA)>public green space (PGS). PAHs in CEA mainly came from coal combustion, while soils of RSA exhibited clear traffic emission characteristics. PAHs in other land uses came from mixed sources. Principle component analysis followed by multivariate linear regression indicated that coal combustion and vehicle emission contributed about 46.0% and 54.0% to PAHs in Beijing's urban soils, respectively. Risk assessment based on the Canadian soil criterion indicated a low contamination level of PAHs. However, higher contents in some sensitive land uses such as CEA and CG should draw enough attention. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Background, short-term and potential long-term denitrification capacity of soils in urbanized coastal watersheds on Kiawah Island, South Carolina, USA

Treesearch

S.R. Drescher; A.J. Lewitus; S.D. Brown

2006-01-01

Urbanization is escalating in many coastal areas of the US and is associated with deteriorating water quality. Often the associated changes in land use result in an overabundance of nutrients and other types of pollution entering ground and surface waters. It is important that we understand biogeochemical transformation processes on urbanizing watersheds if we are to...

Identifying Local Scale Climate Zones of Urban Heat Island from HJ-1B Satellite Data Using Self-Organizing Maps

NASA Astrophysics Data System (ADS)

Wei, C. Z.; Blaschke, T.

2016-10-01

With the increasing acceleration of urbanization, the degeneration of the environment and the Urban Heat Island (UHI) has attracted more and more attention. Quantitative delineation of UHI has become crucial for a better understanding of the interregional interaction between urbanization processes and the urban environment system. First of all, our study used medium resolution Chinese satellite data-HJ-1B as the Earth Observation data source to derive parameters, including the percentage of Impervious Surface Areas, Land Surface Temperature, Land Surface Albedo, Normalized Differential Vegetation Index, and object edge detector indicators (Mean of Inner Border, Mean of Outer border) in the city of Guangzhou, China. Secondly, in order to establish a model to delineate the local climate zones of UHI, we used the Principal Component Analysis to explore the correlations between all these parameters, and estimate their contributions to the principal components of UHI zones. Finally, depending on the results of the PCA, we chose the most suitable parameters to classify the urban climate zones based on a Self-Organization Map (SOM). The results show that all six parameters are closely correlated with each other and have a high percentage of cumulative (95%) in the first two principal components. Therefore, the SOM algorithm automatically categorized the city of Guangzhou into five classes of UHI zones using these six spectral, structural and climate parameters as inputs. UHI zones have distinguishable physical characteristics, and could potentially help to provide the basis and decision support for further sustainable urban planning.

Urban cover mapping using digital, high-resolution aerial imagery

Treesearch

Soojeong Myeong; David J. Nowak; Paul F. Hopkins; Robert H. Brock

2003-01-01

High-spatial resolution digital color-infrared aerial imagery of Syracuse, NY was analyzed to test methods for developing land cover classifications for an urban area. Five cover types were mapped: tree/shrub, grass/herbaceous, bare soil, water and impervious surface. Challenges in high-spatial resolution imagery such as shadow effect and similarity in spectral...

The Application of Satellite-Derived, High-Resolution Land Use/Land Cover Data to Improve Urban Air Quality Model Forecasts

NASA Technical Reports Server (NTRS)

Quattrochi, D. A.; Lapenta, W. M.; Crosson, W. L.; Estes, M. G., Jr.; Limaye, A.; Kahn, M.

2006-01-01

Local and state agencies are responsible for developing state implementation plans to meet National Ambient Air Quality Standards. Numerical models used for this purpose simulate the transport and transformation of criteria pollutants and their precursors. The specification of land use/land cover (LULC) plays an important role in controlling modeled surface meteorology and emissions. NASA researchers have worked with partners and Atlanta stakeholders to incorporate an improved high-resolution LULC dataset for the Atlanta area within their modeling system and to assess meteorological and air quality impacts of Urban Heat Island (UHI) mitigation strategies. The new LULC dataset provides a more accurate representation of land use, has the potential to improve model accuracy, and facilitates prediction of LULC changes. Use of the new LULC dataset for two summertime episodes improved meteorological forecasts, with an existing daytime cold bias of approx. equal to 3 C reduced by 30%. Model performance for ozone prediction did not show improvement. In addition, LULC changes due to Atlanta area urbanization were predicted through 2030, for which model simulations predict higher urban air temperatures. The incorporation of UHI mitigation strategies partially offset this warming trend. The data and modeling methods used are generally applicable to other U.S. cities.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ke, Yinghai; Coleman, Andre M.; Diefenderfer, Heida L.

We delineated 8 watersheds contributing to previously defined river reaches within the 1,468-km2 historical floodplain of the tidally influenced lower Columbia River and estuary. We assessed land-cover change at the watershed, reach, and restoration site scales by reclassifying remote-sensing data from the National Oceanic and Atmospheric Administration Coastal Change Analysis Program’s land cover/land change product into forest, wetland, and urban categories. The analysis showed a 198.3 km2 loss of forest cover during the first 6 years of the Columbia Estuary Ecosystem Restoration Program, 2001–2006. Total measured urbanization in the contributing watersheds of the estuary during the full 1996-2006 change analysismore » period was 48.4 km2. Trends in forest gain/loss and urbanization differed between watersheds. Wetland gains and losses were within the margin of error of the satellite imagery analysis. No significant land cover change was measured at restoration sites, although it was visible in aerial imagery, therefore, the 30-m land-cover product may not be appropriate for assessment of early-stage wetland restoration. These findings suggest that floodplain restoration sites in reaches downstream of watersheds with decreasing forest cover will be subject to increased sediment loads, and those downstream of urbanization will experience effects of increased impervious surfaces on hydrologic processes.« less

Land use and Hydrological Characteristics of Volcanic Urban Soils for Flood Susceptibility Modeling, Ciudad de Colima (Mexico)

NASA Astrophysics Data System (ADS)

Perez Gonzalez, M. L.; Capra, L.; Borselli, L.; Ortiz, A.

2015-12-01

The fast population rate growth and the unplanned urban development has created an increase of urban floods in the City of Colima. Land use change has transformed the hydrological behavior of the watersheds that participates on the runoff-infiltration processes that governs the pluvial concentrations. After the urban areas enlargement, 13% from 2010 to 2015, rainfall has caused significant damages to the downtown community. Therefore it is important to define the main hydraulic properties of the soils surrounding the city. The soil of the region is derived from the debris avalanche deposits of the Volcano of Colima. The volcanic soil cover is only 10 to 15 cm depth. To test the soils of the region, sampling locations were chosen after making a land use map from a Landsat image. The map was done by selecting and dividing similar surface images patterns into three main classifications: Natural (N1), Agricultural (N5) and Urban (N4) surfaces. Thirty-Three soil samples were collected and grouped in nine out of ten land use subdivisions. The 10thsubdivision, represents the completed urbanized area. The land use model is made using spot 4 1A images from the year 2010 up to year 2015. This land use evolutionary analysis will be a base to evaluate the change of the runoff-infiltration rate, direction, and concentration areas for the future flood susceptibility model. To get the parameters above, several soil analysis were performed. The results were that all the soil samples tested were classified as sandy soils. The water content values were from 7% (N4) to 45% (N1) while bulk density values for the same sample were form 0.65 (N1) to 1.50 (N4) g/cm3. The particle density and the porosity values were from 1.65 g/cm3 /5.5% (N4) - 2.65 g/cm3/ 75.40% (N1). The organic matter content was around 0.1% for urban soils and up to 6% on natural and agricultural soils. Some other test like electric conductivity and pH were performed. The obtained parameters were used to get other soil characteristics using the Pedotransfer Functions. The hydraulic conductivity measured in situ using a Drip-Infiltrometer device provide Ks values of 4.5, 2.4 and 5 cm/h for urban, agricultural and natural soils respectively. The information described is integrated on a GIS data base and it is an input for the Flood Susceptibility Model of Colima's metropolitan area on progress.

Spatio-temporal footprints of urbanisation in Surat, the Diamond City of India (1990-2009).

PubMed

Sharma, Richa; Ghosh, Aniruddha; Joshi, Pawan Kumar

2013-04-01

Urbanisation is a ubiquitous phenomenon with greater prominence in developing nations. Urban expansion involves land conversions from vegetated moisture-rich to impervious moisture-deficient land surfaces. The urban land transformations alter biophysical parameters in a mode that promotes development of heat islands and degrades environmental health. This study elaborates relationships among various environmental variables using remote sensing dataset to study spatio-temporal footprint of urbanisation in Surat city. Landsat Thematic Mapper satellite data were used in conjugation with geo-spatial techniques to study urbanisation and correlation among various satellite-derived biophysical parameters, [Normalised Difference Vegetation Index, Normalised Difference Built-up Index, Normalised Difference Water Index, Normalised Difference Bareness Index, Modified NDWI and land surface temperature (LST)]. Land use land cover was prepared using hierarchical decision tree classification with an accuracy of 90.4 % (kappa = 0.88) for 1990 and 85 % (kappa = 0.81) for 2009. It was found that the city has expanded over 42.75 km(2) within a decade, and these changes resulted in elevated surface temperatures. For example, transformation from vegetation to built-up has resulted in 5.5 ± 2.6 °C increase in land surface temperature, vegetation to fallow 6.7 ± 3 °C, fallow to built-up is 3.5 ± 2.9 °C and built-up to dense built-up is 5.3 ± 2.8 °C. Directional profiling for LST was done to study spatial patterns of LST in and around Surat city. Emergence of two new LST peaks for 2009 was observed in N-S and NE-SW profiles.

The impact of projected increases in urbanization on ecosystem services.

PubMed

Eigenbrod, F; Bell, V A; Davies, H N; Heinemeyer, A; Armsworth, P R; Gaston, K J

2011-11-07

Alteration in land use is likely to be a major driver of changes in the distribution of ecosystem services before 2050. In Europe, urbanization will probably be the main cause of land-use change. This increase in urbanization will result in spatial shifts in both supplies of ecosystem services and the beneficiaries of those services; the net outcome of such shifts remains to be determined. Here, we model changes in urban land cover in Britain based on large (16%) projected increases in the human population by 2031, and the consequences for three different services--flood mitigation, agricultural production and carbon storage. We show that under a scenario of densification of urban areas, the combined effect of increasing population and loss of permeable surfaces is likely to result in 1.7 million people living within 1 km of rivers with at least 10 per cent increases in projected peak flows, but that increasing suburban 'sprawl' will have little effect on flood mitigation services. Conversely, losses of stored carbon and agricultural production are over three times as high under the sprawl as under the 'densification' urban growth scenarios. Our results illustrate the challenges of meeting, but also of predicting, future demands and patterns of ecosystem services in the face of increasing urbanization.

The impact of projected increases in urbanization on ecosystem services

PubMed Central

Eigenbrod, F.; Bell, V. A.; Davies, H. N.; Heinemeyer, A.; Armsworth, P. R.; Gaston, K. J.

2011-01-01

Alteration in land use is likely to be a major driver of changes in the distribution of ecosystem services before 2050. In Europe, urbanization will probably be the main cause of land-use change. This increase in urbanization will result in spatial shifts in both supplies of ecosystem services and the beneficiaries of those services; the net outcome of such shifts remains to be determined. Here, we model changes in urban land cover in Britain based on large (16%) projected increases in the human population by 2031, and the consequences for three different services—flood mitigation, agricultural production and carbon storage. We show that under a scenario of densification of urban areas, the combined effect of increasing population and loss of permeable surfaces is likely to result in 1.7 million people living within 1 km of rivers with at least 10 per cent increases in projected peak flows, but that increasing suburban ‘sprawl’ will have little effect on flood mitigation services. Conversely, losses of stored carbon and agricultural production are over three times as high under the sprawl as under the ‘densification’ urban growth scenarios. Our results illustrate the challenges of meeting, but also of predicting, future demands and patterns of ecosystem services in the face of increasing urbanization. PMID:21389035

Analysis of Vegetation Index Variations and the Asian Monsoon Climate

NASA Technical Reports Server (NTRS)

Shen, Sunhung; Leptoukh, Gregory G.; Gerasimov, Irina

2012-01-01

Vegetation growth depends on local climate. Significant anthropogenic land cover and land use change activities over Asia have changed vegetation distribution as well. On the other hand, vegetation is one of the important land surface variables that influence the Asian Monsoon variability through controlling atmospheric energy and water vapor conditions. In this presentation, the mean and variations of vegetation index of last decade at regional scale resolution (5km and higher) from MODIS have been analyzed. Results indicate that the vegetation index has been reduced significantly during last decade over fast urbanization areas in east China, such as Yangtze River Delta, where local surface temperatures were increased significantly in term of urban heat Island. The relationship between vegetation Index and climate (surface temperature, precipitation) over a grassland in northern Asia and over a woody savannas in southeast Asia are studied. In supporting Monsoon Asian Integrated Regional Study (MAIRS) program, the data in this study have been integrated into Giovanni, the online visualization and analysis system at NASA GES DISC. Most images in this presentation are generated from Giovanni system.

Built Expansion and Global Climate Change Drive Projected Urban Heat: Relative Magnitudes, Interactions, and Mitigation

NASA Astrophysics Data System (ADS)

Krayenhoff, E. S.; Georgescu, M.; Moustaoui, M.

2016-12-01

Surface climates are projected to warm due to global climate change over the course of the 21st century, and demographic projections suggest urban areas in the United States will continue to expand and develop, with associated local climate outcomes. Interactions between these two drivers of urban heat have not been robustly quantified to date. Here, simulations with the Weather Research and Forecasting model (coupled to a Single-Layer Urban Canopy Model) are performed at 20 km resolution over the continental U.S. for two 10-year periods: contemporary (2000-2009) and end-of-century (2090-2099). Present and end of century urban land use are derived from the Environmental Protection Agency's Integrated Climate and Land-Use Scenarios. Modelled effects on urban climates are evaluated regionally. Sensitivity to climate projection (Community Climate System Model 4.0, RCP 4.5 vs. RCP 8.5) and associated urban development scenarios are assessed. Effects on near-surface urban air temperature of RCP8.5 climate change are greater than those attributable to the corresponding urban development in many regions. Interaction effects vary by region, and while of lesser magnitude, are not negligible. Moreover, urban development and its interactions with RCP8.5 climate change modify the distribution of convective precipitation over the eastern US. Interaction effects result from the different meteorological effects of urban areas under current and future climate. Finally, the potential for design implementations such as green roofs and high albedo roofs to offset the projected warming is considered. Impacts of these implementations on precipitation are also assessed.

Quantifying avian nest survival along an urbanization gradient using citizen- and scientist-generated data.

PubMed

Ryder, Thomas B; Reitsma, Robert; Evans, Brian; Marra, Peter P

2010-03-01

Despite the increasing pace of urbanization little is known about the factors that limit bird populations (i.e., population-level processes) within the urban/suburban land-use matrix. Here, we report rates of nest survival within the matrix of an urban land-use gradient in the greater Washington, D.C., USA, area for five common songbirds using data collected by scientists and citizens as part of a project called Neighborhood Nestwatch. Using program MARK, we modeled the effects of species, urbanization at multiple spatial scales (canopy cover and impervious surface), and observer (citizen vs. scientist) on nest survival of four open-cup and one cavity-nesting species. In addition, artificial nests were used to determine the relative impacts of specific predators along the land-use gradient. Our results suggest that predation on nests within the land-use matrix declines with urbanization but that there are species-specific differences. Moreover, variation in nest survival among species was best explained by urbanization metrics measured at larger "neighborhood" spatial scales (e.g., 1000 m). Trends were supported by data from artificial nests and suggest that variable predator communities (avian vs. mammalian) are one possible mechanism to explain differential nest survival. In addition, we assessed the quality of citizen science data and show that citizens had no negative effect on nest survival and provided estimates of nest survival comparable to Smithsonian biologists. Although birds nesting within the urban matrix experienced higher nest survival, individuals also faced a multitude of other challenges such as contaminants and invasive species, all of which could reduce adult survival.

Geochemical Indicators of Urban Development in Tributaries and Springs along the Bull Creek Watershed, Austin, TX

NASA Astrophysics Data System (ADS)

Senison, J. J.; Banner, J. L.; Reyes, D.; Sharp, J. M.

2012-12-01

Urbanization can cause significant changes to both flow and water quality in streams and tributaries. In the Austin, Texas, area, previous studies have demonstrated that streamwater strontium isotope compositions (87Sr/86Sr) correlate with measures of urbanization when comparing non-urbanized streams to their urban counterparts. The inclusion of municipal water into natural surface water is inferred from the mean 87Sr/86Sr value found in urbanized streams, which falls between the high value in treated municipal water and the lower values found in local surface streams sourcing from non-urbanized catchments. Fluoride is added to municipal tap water in the treatment process, and a correlation between 87Sr/86Sr and fluoride is observed in streamwater sampled from the watersheds around Austin. These relationships represent some of the principal findings reported in Christian et al. (2011). Current research is testing the hypothesis that municipal water influx in urban areas is a primary modifier of stream- and spring-water chemistry in a single watershed that contains a strong gradient in land use. We compare 87Sr/86Sr and other chemical constituents with potential contributing endmembers, such as municipal tap water and wastewater, local soil and rock leachates, and land use within the Bull Creek watershed. As a consequence of the history of land development, some Bull Creek tributaries are sourced and flow almost entirely in fully-developed areas, whereas others are located in protected natural areas. Thirteen tributaries were monitored and classified as either urbanized or non-urbanized based upon land use within the tributary catchment. Springs in the Bull Creek watershed were also sampled and are similarly classified. The Bull Creek watershed is composed of Lower Cretaceous limestone with significantly lower 87Sr/86Sr than that of municipal water taken from the Lower Colorado River, which is underlain in part by Precambrian rocks upstream of Austin. There are notable differences in urbanized vs. non-urbanized watersheds in mean concentrations of fluoride (urbanized: 0.27 ± 0.08 vs. non-urbanized: 0.19 ± 0.01 ppm), sodium (34.7 ± 17.3 vs. 8.4 ± 1.0 ppm), and potassium (2.9 ± 0.8 vs. 1.2 ± 0.2 ppm), consistent with higher concentrations in municipal water contributing to the urbanized tributaries. Springwater demonstrates similar divergences for these ions. 87Sr/86Sr for the springs falls within a narrow range for non-urbanized springs (0.7079-0.7081), similar to Cretaceous limestone values, whereas urbanized springs contain a larger range (0.7077-0.7087). These results are consistent with urbanization effects in the Bull Creek watershed.

The urban heat island in Rio de Janeiro, Brazil, in the last 30 years using remote sensing data

NASA Astrophysics Data System (ADS)

Peres, Leonardo de Faria; Lucena, Andrews José de; Rotunno Filho, Otto Corrêa; França, José Ricardo de Almeida

2018-02-01

The aim of this work is to study urban heat island (UHI) in Metropolitan Area of Rio de Janeiro (MARJ) based on the analysis of land-surface temperature (LST) and land-use patterns retrieved from Landsat-5/Thematic Mapper (TM), Landsat-7/Enhanced Thematic Mapper Plus (ETM+) and Landsat-8/Operational Land Imager (OLI) and Thermal Infrared Sensors (TIRS) data covering a 32-year period between 1984 and 2015. LST temporal evolution is assessed by comparing the average LST composites for 1984-1999 and 2000-2015 where the parametric Student t-test was conducted at 5% significance level to map the pixels where LST for the more recent period is statistically significantly greater than the previous one. The non-parametric Mann-Whitney-Wilcoxon rank sum test has also confirmed at the same 5% significance level that the more recent period (2000-2015) has higher LST values. UHI intensity between ;urban; and ;rural/urban low density; (;vegetation;) areas for 1984-1999 and 2000-2015 was established and confirmed by both parametric and non-parametric tests at 1% significance level as 3.3 °C (5.1 °C) and 4.4 °C (7.1 °C), respectively. LST has statistically significantly (p-value < 0.01) increased over time in two of three land cover classes (;urban; and ;urban low density;), respectively by 1.9 °C and 0.9 °C, except in ;vegetation; class. A spatial analysis was also performed to identify the urban pixels within MARJ where UHI is more intense by subtracting the LST of these pixels from the LST mean value of ;vegetation; land-use class.

Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs

PubMed Central

Edmondson, J. L.; Stott, I.; Davies, Z. G.; Gaston, K. J.; Leake, J. R.

2016-01-01

Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health. PMID:27641002

Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs.

PubMed

Edmondson, J L; Stott, I; Davies, Z G; Gaston, K J; Leake, J R

2016-09-19

Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health.

Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs

NASA Astrophysics Data System (ADS)

Edmondson, J. L.; Stott, I.; Davies, Z. G.; Gaston, K. J.; Leake, J. R.

2016-09-01

Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health.

The Use of ATLAS Data to Quantify Surface Radiative Budgets in Four US Cities

NASA Technical Reports Server (NTRS)

Luvall, Jeffrey; Gonzalez, Jorge; Rickman, Douglas; Quattrochi, Dale; Schiller, Steve; Comarazamy, Daniel; Estes, Maury

2011-01-01

The additional heating of the air over the city is the result of the replacement of naturally vegetated surfaces with those composed of asphalt, concrete, rooftops and other manmade materials. The temperatures of these artificial surfaces can be 20 to 40 C higher than vegetated surfaces. This produces a dome of elevated air temperatures 5 to 8 C greater over the city, compared to the air temperatures over adjacent rural areas. This effect is called the "urban heat island". Urban landscapes are a complex mixture of vegetated and non-vegetated surfaces. It is difficult to take enough temperature measurements over a large city area to. The use of remotely sensed data from airborne scanners is ideal to characterize the complexity of urban albedo and radiant surface temperatures. The National Aeronautics and Space Administration (NASA) Airborne Thermal and Land Applications Sensor (ATLAS) operates in the visual and IR bands was used to collect data from Salt Lake City, UT, Sacramento, CA, Baton Rouge, LA. And San Juan, Puerto Rico with the main objective of investigating the Urban Heat Island (UHI). In this presentation we will examine the techniques of analyzing remotely sensed data for measuring the effect of various urban surfaces on their contribution to the urban heat island effect.

Urban Thermal Environment Dynamics: A Case Study in Hangzhou During 2005-2015

NASA Astrophysics Data System (ADS)

Sun, W.; Li, F.; Yang, G.

2017-12-01

Hangzhou, as the Capital of Zhejiang Province in East China, has experienced the rapid urbanization process and associated urban heat island effect in the past twenty decades. In this study, we implemented Landsat satellite remote sensing images to investigate the relationship between landscape changes and thermal environment dynamics during 2005-2015 in Hangzhou City. A total of 48 Landsat TM/ETM+/OLR/TIRS images spanning four different seasons were downloaded from the USGS website and utilized in the study. Preprocessing works, i.e., radiometric correction and removing cloud- and fog -contaminated pixels, were conducted, and the land surface temperature (LST) was derived using the radiative transfer equation. Meanwhile, the land use and land cover (LULC) classification was accomplished by using the Support Vector Machine (SVM) classifier, and four main landscape indexes (i.e., Shannon Diversity Index, Landscape Division Index, Shannon Evenness Index, and Aggregation Index) were estimated from the LULC map. Our preliminary results show that: 1) the magnitude of urban thermal environment has obviously increased from 2005 to 2015, and the summer season shows more significant heat island effect than other three seasons; 2) the general landscape pattern of Hangzhou becomes more diversified and fragmentized from 2005 to 2015, and different landscape patterns bring that four different function zones (i.e., urban core zone, tourism function zone, industrial development zone and ecological reservation zone) of Hangzhou have different characteristics in urban thermal environment; 3) significant hot spots of LST point to the construction land while cold spots of LST coincides with the vegetation land.

The National Land Cover Database

USGS Publications Warehouse

Homer, Collin G.; Fry, Joyce A.; Barnes, Christopher A.

2012-01-01

The National Land Cover Database (NLCD) serves as the definitive Landsat-based, 30-meter resolution, land cover database for the Nation. NLCD provides spatial reference and descriptive data for characteristics of the land surface such as thematic class (for example, urban, agriculture, and forest), percent impervious surface, and percent tree canopy cover. NLCD supports a wide variety of Federal, State, local, and nongovernmental applications that seek to assess ecosystem status and health, understand the spatial patterns of biodiversity, predict effects of climate change, and develop land management policy. NLCD products are created by the Multi-Resolution Land Characteristics (MRLC) Consortium, a partnership of Federal agencies led by the U.S. Geological Survey. All NLCD data products are available for download at no charge to the public from the MRLC Web site: http://www.mrlc.gov.

Urban Land: Study of Surface Run-off Composition and Its Dynamics

NASA Astrophysics Data System (ADS)

Palagin, E. D.; Gridneva, M. A.; Bykova, P. G.

2017-11-01

The qualitative composition of urban land surface run-off is liable to significant variations. To study surface run-off dynamics, to examine its behaviour and to discover reasons of these variations, it is relevant to use the mathematical apparatus technique of time series analysis. A seasonal decomposition procedure was applied to a temporary series of monthly dynamics with the annual frequency of seasonal variations in connection with a multiplicative model. The results of the quantitative chemical analysis of surface wastewater of the 22nd Partsjezd outlet in Samara for the period of 2004-2016 were used as basic data. As a result of the analysis, a seasonal pattern of variations in the composition of surface run-off in Samara was identified. Seasonal indices upon 15 waste-water quality indicators were defined. BOD (full), suspended materials, mineralization, chlorides, sulphates, ammonium-ion, nitrite-anion, nitrate-anion, phosphates (phosphorus), iron general, copper, zinc, aluminium, petroleum products, synthetic surfactants (anion-active). Based on the seasonal decomposition of the time series data, the contribution of trends, seasonal and accidental components of the variability of the surface run-off indicators was estimated.

Geographic Analysis and Monitoring Program

USGS Publications Warehouse

Campbell, Jon C.

2007-01-01

The surface of the Earth is changing rapidly, at local, regional, national, and global scales, with significant repercussions for people, the economy, and the environment. Some changes have natural causes, such as wildland fires or hurricanes, while other changes on the land, such as resource extraction, agricultural practices, and urban growth, are human-induced processes. There are other types of changes that are a combination of natural and human-induced factors; landslides and floods, for example, are fundamentally natural processes that are often intensified or accelerated by human land use practices. Whatever their cause, land-surface changes can have profound environmental and economic impacts.

Analysis of The Surface Radiative Budget Using ATLAS Data for San Juan, Puerto Rico

NASA Technical Reports Server (NTRS)

Luvall, Jeffrey C.; Rickman, D. L.; Gonzalez, J.; Comarazamy, Daniel; Picon, Ana

2007-01-01

The additional beating of the air over the city is the result of the replacement of naturally vegetated surfaces with those composed of asphalt, concrete, rooftops and other man-made materials. The temperatures of these artificial surfaces can be 20 to 40 C higher than vegetated surfaces. This produces a dome of elevated air temperatures 5 to 8 C greater over the city, compared to the air temperatures over adjacent rural areas. Urban landscapes are a complex mixture of vegetated and nonvegetated surfaces. It is difficult to take enough temperature measurements over a large city area to characterize the complexity of urban radiant surface temperature variability. The NASA Airborne Thermal and Land Applications Sensor (ATLAS) operates in the visual and IR bands was used in February 2004 to collect data from San Juan, Puerto Rico with the main objective of investigating the Urban Heat Island (UHI) in tropical cities.

The urban heat island in the city of Poznań as derived from Landsat 5 TM

NASA Astrophysics Data System (ADS)

Majkowska, Agnieszka; Kolendowicz, Leszek; Półrolniczak, Marek; Hauke, Jan; Czernecki, Bartosz

2017-05-01

To study urban heat island (UHI), Landsat 5 TM data and in situ measurements of air temperature from nine points in Poznań (Poland) for the period June 2008-May 2013 were used. Based on data from measurement points located in different types of land use, the surface urban heat island (SUHI) maps were created. All available and quality-controlled Landsat 5 TM images from 15 unique days were used to obtain the characteristics of land surface temperature (LST) and UHI intensity. In addition, spatial analysis of UHI was conducted on the basis of Corine Land Cover 2006 dataset. In situ measurements at a height of 2 m above ground level show that the UHI is a common occurrence in Poznań with a mean annual intensity of 1.0 °C. The UHI intensity is greater during the warm half of the year. Moreover, results based on the remote sensing data and the Corine Land Cover 2006 indicate that the highest value of the mean LST anomalies (3.4 °C) is attained by the continuous urban fabric, while the lowest value occurs within the broad-leaved forests (-3.1 °C). To re-count from LST to the air temperature at a height of 2 m above ground level ( T agl), linear and non-linear regression models were created. For both models, coefficients of determination equal about 0.80, with slightly higher value for the non-linear approach, which was applied to estimate the T agl spatial variability over the city of Poznań.

Land use planning and surface heat island formation: A parcel-based radiation flux approach

NASA Astrophysics Data System (ADS)

Stone, Brian; Norman, John M.

This article presents a study of residential parcel design and surface heat island formation in a major metropolitan region of the southeastern United States. Through the integration of high-resolution multispectral data (10 m) with property tax records for over 100,000 single-family residential parcels in the Atlanta, Georgia, metropolitan region, the influence of the size and material composition of residential land use on an indicator of surface heat island formation is reported. In contrast to previous work on the urban heat island, this study derives a parcel-based indicator of surface warming to permit the impact of land use planning regulations governing the density and design of development on the excess surface flux of heat energy to be measured. The results of this study suggest that the contribution of individual land parcels to regional surface heat island formation could be reduced by approximately 40% through the adoption of specific land use planning policies, such as zoning and subdivision regulations, and with no modifications to the size or albedo of the residential structure.

Incorporating Land-Use Mapping Uncertainty in Remote Sensing Based Calibration of Land-Use Change Models

NASA Astrophysics Data System (ADS)

Cockx, K.; Van de Voorde, T.; Canters, F.; Poelmans, L.; Uljee, I.; Engelen, G.; de Jong, K.; Karssenberg, D.; van der Kwast, J.

2013-05-01

Building urban growth models typically involves a process of historic calibration based on historic time series of land-use maps, usually obtained from satellite imagery. Both the remote sensing data analysis to infer land use and the subsequent modelling of land-use change are subject to uncertainties, which may have an impact on the accuracy of future land-use predictions. Our research aims to quantify and reduce these uncertainties by means of a particle filter data assimilation approach that incorporates uncertainty in land-use mapping and land-use model parameter assessment into the calibration process. This paper focuses on part of this work, more in particular the modelling of uncertainties associated with the impervious surface cover estimation and urban land-use classification adopted in the land-use mapping approach. Both stages are submitted to a Monte Carlo simulation to assess their relative contribution to and their combined impact on the uncertainty in the derived land-use maps. The approach was applied on the central part of the Flanders region (Belgium), using a time-series of Landsat/SPOT-HRV data covering the years 1987, 1996, 2005 and 2012. Although the most likely land-use map obtained from the simulation is very similar to the original classification, it is shown that the errors related to the impervious surface sub-pixel fraction estimation have a strong impact on the land-use map's uncertainty. Hence, incorporating uncertainty in the land-use change model calibration through particle filter data assimilation is proposed to address the uncertainty observed in the derived land-use maps and to reduce uncertainty in future land-use predictions.

Urban thermal environment and its biophysical parameters derived from satellite remote sensing imagery

NASA Astrophysics Data System (ADS)

Zoran, Maria A.; Savastru, Roxana S.; Savastru, Dan M.; Tautan, Marina N.; Baschir, Laurentiu V.

2013-10-01

In frame of global warming, the field of urbanization and urban thermal environment are important issues among scientists all over the world. This paper investigated the influences of urbanization on urban thermal environment as well as the relationships of thermal characteristics to other biophysical variables in Bucharest metropolitan area of Romania based on satellite remote sensing imagery Landsat TM/ETM+, time series MODIS Terra/Aqua data and IKONOS acquired during 1990 - 2012 period. Vegetation abundances and percent impervious surfaces were derived by means of linear spectral mixture model, and a method for effectively enhancing impervious surface has been developed to accurately examine the urban growth. The land surface temperature (Ts), a key parameter for urban thermal characteristics analysis, was also retrieved from thermal infrared band of Landsat TM/ETM+, from MODIS Terra/Aqua datasets. Based on these parameters, the urban growth, urban heat island effect (UHI) and the relationships of Ts to other biophysical parameters have been analyzed. Results indicated that the metropolitan area ratio of impervious surface in Bucharest increased significantly during two decades investigated period, the intensity of urban heat island and heat wave events being most significant. The correlation analyses revealed that, at the pixel-scale, Ts possessed a strong positive correlation with percent impervious surfaces and negative correlation with vegetation abundances at the regional scale, respectively. This analysis provided an integrated research scheme and the findings can be very useful for urban ecosystem modeling.

Quantifying the influences of various ecological factors on land surface temperature of urban forests.

PubMed

Ren, Yin; Deng, Lu-Ying; Zuo, Shu-Di; Song, Xiao-Dong; Liao, Yi-Lan; Xu, Cheng-Dong; Chen, Qi; Hua, Li-Zhong; Li, Zheng-Wei

2016-09-01

Identifying factors that influence the land surface temperature (LST) of urban forests can help improve simulations and predictions of spatial patterns of urban cool islands. This requires a quantitative analytical method that combines spatial statistical analysis with multi-source observational data. The purpose of this study was to reveal how human activities and ecological factors jointly influence LST in clustering regions (hot or cool spots) of urban forests. Using Xiamen City, China from 1996 to 2006 as a case study, we explored the interactions between human activities and ecological factors, as well as their influences on urban forest LST. Population density was selected as a proxy for human activity. We integrated multi-source data (forest inventory, digital elevation models (DEM), population, and remote sensing imagery) to develop a database on a unified urban scale. The driving mechanism of urban forest LST was revealed through a combination of multi-source spatial data and spatial statistical analysis of clustering regions. The results showed that the main factors contributing to urban forest LST were dominant tree species and elevation. The interactions between human activity and specific ecological factors linearly or nonlinearly increased LST in urban forests. Strong interactions between elevation and dominant species were generally observed and were prevalent in either hot or cold spots areas in different years. In conclusion, quantitative studies based on spatial statistics and GeogDetector models should be conducted in urban areas to reveal interactions between human activities, ecological factors, and LST. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of Thermal Inertia on Urban Climatology: A Case Study of Delhi

NASA Astrophysics Data System (ADS)

Berwal, S.; Kumar, D.; Singh, V. P.; Pandey, A. K.; Kumar, K.

2016-12-01

The ability with which a material can absorb, restore the heat and release it later during the nighttime is known as thermal inertia. In the context to urban areas, it measures the sub-surface's ability to store heat during the day and release it during the night. It prevents the overheating in summer and maintains heat during the winter thereby safeguarding the building comfort level. Due to huge population and urban sprawl this study can be very useful for Delhi and cities like it. The climatic modification in the context of urban areas due to human activities in relation to rural areas is termed as the urban heat island effect (UHI). The modelling for formation of urban UHI has been done using the geospatial technique. Apart from temperature, the amount of dust in the atmosphere is also a significant contributor in modifying the UHI formation. It is also an attempt to establish the role of land use and land cover patterns and respective thermal inertia affecting this phenomenon. The thermal inertia over Delhi-NCR was estimated using surface albedo and daytime-nighttime temperature differences from MODIS datasets. Higher thermal inertia were observed in urban areas than that of rural areas during the analysis of the thermal inertia maps. Furthermore, the study also reveals that the urban heat island intensity (UHI) and the thermal inertia has a relationship of strong inverse correlation. The results of this study will provide useful insights for urban planners and the local governments to devise appropriate strategies for making the urban climate favourable for the city residents.

Diurnal changes in urban boundary layer environment induced by urban greening

NASA Astrophysics Data System (ADS)

Song, Jiyun; Wang, Zhi-Hua

2016-11-01

Urban green infrastructure has been widely used for mitigating adverse environmental problems as well as enhancing urban sustainability of cities worldwide. Here we develop an integrated urban-land-atmosphere modeling framework with the land surface processes parameterized by an advanced urban canopy model and the atmospheric processes parameterized by a single column model. The model is then applied to simulate a variety of forms of green infrastructure, including urban lawns, shade trees, green and cool roofs, and their impact on environmental changes in the total urban boundary layer (UBL) for a stereotypical desert city, viz. Phoenix, Arizona. It was found that green roofs have a relatively uniform cooling effect proportional to their areal coverage. In particular, a reduction of UBL temperature of 0.3 °C and 0.2 °C per 10% increase of green roof coverage was observed at daytime and nighttime, respectively. In contrast, the effect of greening of street canyons is constrained by the overall abundance of green infrastructure and the energy available for evapotranspiration. In addition, the increase in urban greening causes boundary-layer height to decrease during daytime but increase at nighttime, leading to different trends of changes in urban air quality throughout a diurnal cycle.

Estimating the Effects of Conversion of Agricultural Land to Urban Land on Deep Percolation of Irrigation Water in the Grand Valley, Western Colorado

USGS Publications Warehouse

Mayo, John W.

2008-01-01

The conversion of agricultural land to urban residential land is associated with rapid population growth in the Grand Valley of western Colorado. Information regarding the effects of this land-use conversion on deep percolation, irrigation-water application, and associated salt loading to the Colorado River is needed to support water-resource planning and conservation efforts. The Natural Resources Conservation Service (NRCS) assessed deep percolation and estimated salt loading derived from irrigated agricultural lands in the Grand Valley in a 1985 to 2002 monitoring and evaluation study (NRCS M&E). The U.S. Geological Survey (USGS), in cooperation with the Colorado River Salinity Control Forum and the Mesa Conservation District, quantified the current (2005-2006) deep percolation and irrigation-water application characteristics of 1/4-acre residential lots and 5-acre estates, urban parks, and urban orchard grass fields in the Grand Valley, and compared the results to NRCS M&E results from alfalfa-crop sites. In addition, pond seepage from three irrigation-water holding ponds was estimated. Salt loading was estimated for the urban study results and the NRCS M&E results by using standard salt-loading factors. A daily soil-moisture balance calculation technique was used at all urban study irrigated sites. Deep percolation was defined as any water infiltrating below the top 12 inches of soil. Deep percolation occurred when the soil-moisture balance in the first 12 inches of soil exceeded the field capacity for the soil type at each site. Results were reported separately for urban study bluegrass-only sites and for all-vegetation type (bluegrass, native plants, and orchard grass) sites. Deep percolation and irrigation-water application also were estimated for a complete irrigation season at three subdivisions by using mean site data from each subdivision. It was estimated that for the three subdivisions, 37 percent of the developed acreage was irrigated (the balance being impermeable surfaces).

Metal Distribution in Urban Agricultural Soils in the Inland Empire, California

NASA Astrophysics Data System (ADS)

Marin, C. C. E.

2015-12-01

Urban environments exhibit unique biogeochemistry due to the presence of a myriad of anthropogenic sources of contaminants. One potential route through which humans have been exposed to metal contaminants is the ingestion of food produced on urban soils. The Inland Empire is a metropolitan located in semi-arid region of Southern California with greater than 4 million residents, where the growing population is demonstrating an increase in citizen participation in contributing to expanding local food systems. In response to the demand for locally grown produce, the Inland Empire is undergoing rapid land use change, where large tracts of land on the periphery of cities, including Riverside, are being converted or set aside for urban agriculture, though the quality of the soil for food production is unknown. At the same time, smaller gardens and farms are growing in number within the more densely populated areas. Assessing the quality of urban soil currently used for food production in this region can aid in projecting how land use change will affect the quality of crops produced as urban agriculture continues to expand in arid regions. Soil samples were taken from a variety of land use types, including areas currently producing crops and areas set aside for future large scale food production. Samples were collected at the surface (0-2 cm) and below till depth (20-22 cm). These soils were analyzed for total carbon including organic and inorganic carbon fractions, total nitrogen, bulk metal and trace metal concentrations (including As, Mn, Cr, Pb, Cd, Zn, and Cu). To approximate the mobility of the trace elements under various conditions, extraction tests were also performed, including EPA Pb bioavailability analysis. Finally, we utilize statistical tools and spatial analysis to illustrate the relationship between previous land use, current land use, and soil quality for urban crop production.

Spatially Complete Global Spectral Surface Albedos: Value-Added Datasets Derived from Terra MODIS Land Products

NASA Technical Reports Server (NTRS)

Moody, Eric G.; King, Michael D.; Platnick, Steven; Schaaf, Crystal B.; Gao, Feng

2004-01-01

Land surface albedo is an important parameter in describing the radiative properties of the earth s surface as it represents the amount of incoming solar radiation that is reflected from the surface. The amount and type of vegetation of the surface dramatically alters the amount of radiation that is reflected; for example, croplands that contain leafy vegetation will reflect radiation very differently than blacktop associated with urban areas. In addition, since vegetation goes through a growth, or phenological, cycle, the amount of radiation that is reflected changes over the course of a year. As a result, albedo is both temporally and spatially dependant upon global location as there is a distribution of vegetated surface types and growing conditions. Land surface albedo is critical for a wide variety of earth system research projects including but not restricted to remote sensing of atmospheric aerosol and cloud properties from space, ground-based analysis of aerosol optical properties from surface-based sun/sky radiometers, biophysically-based land surface modeling of the exchange of energy, water, momentum, and carbon for various land use categories, and surface energy balance studies. These projects require proper representation of the surface albedo s spatial, spectral, and temporal variations, however, these representations are often lacking in datasets prior to the latest generation of land surface albedo products.

150 years of land degradation and development: loss of habitats, natural resources due to quarrying and industrialization followed by land reclamation in the heart of Budapest city

NASA Astrophysics Data System (ADS)

Török, Ákos

2017-04-01

The urban development and land degradation is an accelerated process in the 21st century; however several examples are known when this happened in the past. A historic case study is discussed in this research when clump of three former small towns (named: Buda, Pest and Óbuda) became a million population city more than hundred years ago invoking significant land degradation, drastic and surprising changes in land use. Budapest which is now the capital of Hungary has seen rapid land use changes in the past 150 years especially from 1850'ies to early 20th century. The population of the city rapidly grown from the end of 19th century to early 20th century; i.e. it is tripled from 1880 to 1920 and reached nearly 1 million in 40 years. This population boom induced significant land degradation, changes in land use and loss of habitats. The paper presents examples how the land use has changed in the past 105 years with historic maps and interpreted cases suggesting different pathways leading to land degradation. The first one focuses on vineyards and grape cultivation and explains how these areas were first converted to limestone quarries to provide construction material to the city and then transformed to urban habitat in the early 20th century again. The cellars - former quarry galleries - than were used for housing (urban habitat) and later were used as storage facilities and mushroom cultivation sites. At present these subsurface openings cause high risk of land development (collapse) and limit the land use of the given area. The current paper also outlines the development of the city via the perspective of natural resources, since drinking water and industrial water need modified the land development and urbanization. Another example is also given how the brewery industry exploited natural resources and the surface water use was shifted to exploitation of karstic waters causing land degradation and drop of water table. Additional example demonstrates how the former drifting sand dunes was conquest and now form parts of the urban habitat. Finally, the 125-year history of gradual loosing of wetland habitats and flood plain forests due to university campus development is also shown. These examples clearly indicate that urban development cause various grades of land degradation and also bring unexpected risks of potential land use.

[Spatial tendency of urban land use in new Yinzhou Town of Ningbo City, Zhejiang Province of East China].

PubMed

Jiang, Wen-Wei; Guo, Hui-Hui; Mei, Yan-Xia

2012-03-01

By adopting gradient analysis combining with the analysis of urban land use degree, this paper studied the spatial layout characteristics of residential and industrial lands in new Yinzhou Town, and explored the location characters of various urban land use by selecting public green land, public facilities, and road as the location advantage factors. Gradient analysis could effectively connect with the spatial layout of urban land use, and quantitatively depict the spatial character of urban land use. In the new town, there was a new urban spatial center mostly within the radius of 2 km, namely, the urban core area had obvious location advantage in the cross-shaft direction urban development. On the south of Yinzhou Avenue, the urban hinterland would be constructed soon. In the future land use of the new town, the focus would be the reasonable vicissitude of industrial land after the adjustment of industrial structure, the high-efficient intensive use of the commercial land restricted by the compulsive condition of urban core area, and the agricultural land protection in the southeastern urban-rural fringe.

"Flooding Risk Analysis and the Understanding of Hydrological Disturbance due to the Rapid Urbanization in a Low-Scale Subwatershed in Houston Area". ( The project develops a relavant Model of flooding risk assessment to define the connection between increased streamflow/flooding and the rapid urban land development).

NASA Astrophysics Data System (ADS)

Geldiyev, P.

2017-12-01

Rapid urban development and changing climate influences the frequency and magnitude of flooding in Houston area. This proposed project aims to evaluate the flooding risks with the current and future land use changes by 2040 for one subbasin of the San Jacinto Brazos/Neches-Trinity Coastal basin. Surface environments and streamflow data of the Clear Creek are analyzed and stimulated to discuss the possible impact of urbanization on the occurrence of floods. The streamflow data is analyzed and simulated with the application of the Geographic Information Systems and its extensions. Both hydrologic and hydraulic models of the Clear Creek are created with the use of HEC-HMS and HEC-RAS software. Both models are duplicated for the year 2040, based on projected 2040 Landcover Maps developed by Houston and Galveston Area Council. This project examines a type of contemporary hydrologic disturbance and the interaction between land cover and changes in hydrological processes. Expected results will be very significant for urban development and flooding management.

How Cities Make Their Own Weather

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall

2004-01-01

Urbanization is one of the extreme cases of land use change. Most of world's population has moved to urban areas. Although currently only 1.2% of the land is considered urban, the spatial coverage and density of cities are expected to rapidly increase in d e near future. It is estimated that by the year 2025, 60% of the world's population will live in cities. Human activity in urban environments also alters weather and climate processes. However, our understanding of urbanization on the total Earth-weather-climate system is incomplete. Recent literature continues to provide evidence that anomalies in precipitation exist over and downwind of major cities. Current and future research efforts are actively seeking to verify these literature findings and understand potential cause-effect relationships. The novelty of this study is that it utilizes rainfall data from multiple satellite data sources (e.g. TRMM precipitation radar, TRMM-geosynchronous-rain gauge merged product, and SSM/I) and ground-based measurements to identify spatial anomalies and temporal trends in precipitation for cities around the world. We will also present results from experiments using a regional atmospheric-land surface modeling system. Early results will be presented and placed within the context of weather prediction, climate assessment, and societal applications.

Integration of land use and land cover inventories for landscape management and planning in Italy.

PubMed

Sallustio, Lorenzo; Munafò, Michele; Riitano, Nicola; Lasserre, Bruno; Fattorini, Lorenzo; Marchetti, Marco

2016-01-01

There are both semantic and technical differences between land use (LU) and land cover (LC) measurements. In cartographic approaches, these differences are often neglected, giving rise to a hybrid classification. The aim of this paper is to provide a better understanding and characterization of the two classification schemes using a comparison that allows maximization of the informative power of both. The analysis was carried out in the Molise region (Central Italy) using sample information from the Italian Land Use Inventory (IUTI). The sampling points were classified with a visual interpretation of aerial photographs for both LU and LC in order to estimate surfaces and assess the changes that occurred between 2000 and 2012. The results underscore the polarization of land use and land cover changes resulting from the following: (a) recolonization of natural surfaces, (b) strong dynamisms between the LC classes in the natural and semi-natural domain and (c) urban sprawl on the lower hills and plains. Most of the observed transitions are attributable to decreases in croplands, natural grasslands and pastures, owing to agricultural abandonment. The results demonstrate that a comparison between LU and LC estimates and their changes provides an understanding of the causes of misalignment between the two criteria. Such information may be useful for planning policies in both natural and semi-natural contexts as well as in urban areas.

Long-Term Effects of Changing Land Use Practices on Surface Water Quality in a Coastal River and Lagoonal Estuary

NASA Astrophysics Data System (ADS)

Rothenberger, Meghan B.; Burkholder, Joann M.; Brownie, Cavell

2009-09-01

The watershed of the Neuse River, a major tributary of the largest lagoonal estuary on the U.S. mainland, has sustained rapid growth of human and swine populations. This study integrated a decade of available land cover and water quality data to examine relationships between land use changes and surface water quality. Geographic Information Systems (GIS) analysis was used to characterize 26 subbasins throughout the watershed for changes in land use during 1992-2001, considering urban, agricultural (cropland, animal as pasture, and densities of confined animal feed operations [CAFOs]), forested, grassland, and wetland categories and numbers of wastewater treatment plants (WWTPs). GIS was also used together with longitudinal regression analysis to identify specific land use characteristics that influenced surface water quality. Total phosphorus concentrations were significantly higher during summer in subbasins with high densities of WWTPs and CAFOs. Nitrate was significantly higher during winter in subbasins with high numbers of WWTPs, and organic nitrogen was higher in subbasins with higher agricultural coverage, especially with high coverage of pastures fertilized with animal manure. Ammonium concentrations were elevated after high precipitation. Overall, wastewater discharges in the upper, increasingly urbanized Neuse basin and intensive swine agriculture in the lower basin have been the highest contributors of nitrogen and phosphorus to receiving surface waters. Although nonpoint sources have been emphasized in the eutrophication of rivers and estuaries such as the Neuse, point sources continue to be major nutrient contributors in watersheds sustaining increasing human population growth. The described correlation and regression analyses represent a rapid, reliable method to relate land use patterns to water quality, and they can be adapted to watersheds in any region.

Remotely Sensed Index of Deforestation/Urbanization for use in Climate Models

NASA Technical Reports Server (NTRS)

Carlson, Toby N.

1996-01-01

The purpose of this investigation is to use a new method for deriving land surface parameters from a combination of thermal infrared and vegetation index measurements from satellites (Landsat-TM, and NOAA-AVHRR) and to integrate these parameters with more conventional data bases. We have completed an investigation of urbanization in the State College, PA area and have begun work in Chester County, PA, and Costa Rica. Our basic hypothesis is that changes in land use, including deforestation, exert a profound influence on local microclimates whose effects may greatly exceed in importance those occurring on larger scales.

Land use inventory of Salt Lake County, Utah from color infrared aerial photography 1982

NASA Technical Reports Server (NTRS)

Price, K. P.; Willie, R. D.; Wheeler, D. J.; Ridd, M. K.

1983-01-01

The preparation of land use maps of Salt Lake County, Utah from high altitude color infrared photography is described. The primary purpose of the maps is to aid in the assessment of the effects of urban development on the agricultural land base and water resources. The first stage of map production was to determine the categories of land use/land cover and the mapping unit detail. The highest level of interpretive detail was given to the land use categories found in the agricultural or urbanized portions of the county; these areas are of primary interest with regard to the consumptive use of water from surface streams and wells. A slightly lower level of mapping detail was given to wetland environments; areas to which water is not purposely diverted by man but which have a high consumptive rate of water use. Photos were interpreted on the basis of color, tone, texture, and pattern, together with features of the topographic, hydrologic, and ecological context.

Modeling the Surface Energy Balance of the Core of an Old Mediterranean City: Marseille.

NASA Astrophysics Data System (ADS)

Lemonsu, A.; Grimmond, C. S. B.; Masson, V.

2004-02-01

The Town Energy Balance (TEB) model, which parameterizes the local-scale energy and water exchanges between urban surfaces and the atmosphere by treating the urban area as a series of urban canyons, coupled to the Interactions between Soil, Biosphere, and Atmosphere (ISBA) scheme, was run in offline mode for Marseille, France. TEB's performance is evaluated with observations of surface temperatures and surface energy balance fluxes collected during the field experiments to constrain models of atmospheric pollution and transport of emissions (ESCOMPTE) urban boundary layer (UBL) campaign. Particular attention was directed to the influence of different surface databases, used for input parameters, on model predictions. Comparison of simulated canyon temperatures with observations resulted in improvements to TEB parameterizations by increasing the ventilation. Evaluation of the model with wall, road, and roof surface temperatures gave good results. The model succeeds in simulating a sensible heat flux larger than heat storage, as observed. A sensitivity comparison using generic dense city parameters, derived from the Coordination of Information on the Environment (CORINE) land cover database, and those from a surface database developed specifically for the Marseille city center shows the importance of correctly documenting the urban surface. Overall, the TEB scheme is shown to be fairly robust, consistent with results from previous studies.

Comparative and Combinative Study of Urban Heat island in Wuhan City with Remote Sensing and CFD Simulation

PubMed Central

Li, Kun; Yu, Zhuang

2008-01-01

Urban heat islands are one of the most critical urban environment heat problems. Landsat ETM+ satellite data were used to investigate the land surface temperature and underlying surface indices such as NDVI and NDBI. A comparative study of the urban heat environment at different scales, times and locations was done to verify the heat island characteristics. Since remote sensing technology has limitations for dynamic flow analysis in the study of urban spaces, a CFD simulation was used to validate the improvement of the heat environment in a city by means of wind. CFD technology has its own shortcomings in parameter setting and verification, while RS technology is helpful to remedy this. The city of Wuhan and its climatological condition of being hot in summer and cold in winter were chosen to verify the comparative and combinative application of RS with CFD in studying the urban heat island. PMID:27873893

High Spatial Resolution Thermal Infrared Remote Sensing Data for Analysis of the Atlanta, Georgia, Urban Heat Island Effect and Its Impacts on the Environment

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.

2007-01-01

The twenty-first century is the first "urban century" according to the United Nations Development Program. The focus of cities reflects awareness of the growing percentage of the world's population that lives in urban areas. In environmental terms, cities are the original producers of many of the global problems related to waste disposal, air and water pollution, and associated environmental and ecological challenges. Expansion of cities, both in population and areal extent, is a relentless process. In 2000, approximately 3 billion people representing about 40% of the global population, resided in urban areas. Urban population will continue to rise substantially over the next several decades according to UN estimates, and most of this growth will Occur in developing countries. The UN estimates that by 2025, 60% of the world's population will live in urban areas. As a consequence, the number of"megacities" (those cities with populations of 10 million inhabitants or more) will increase by 100 by 2025. Thus, there is a critical need to understand urban areas and what their impacts are on environmental, ecological and hydrologic resources, as well as on the local, regional, and even global climate. One of the more egregious side effects of urbanization is the increase in surface and air temperatures that lead to deterioration in air quality. In the United States, under the more stringent air quality guidelines established by the U.S. Environmental Protection Agency in 1997, nearly 300 counties in 34 states will not meet these new air quality standards for ground level ozone. Mitigation of the urban heat island (UHI) effect is actively being evaluated as a possible way to reduce ground ozone levels in cities and assist states in improving air quality. Foremost in the analysis of how the UHI affects air quality and other environmental factors is the use of remote sensing technology and data to characterize urban land covers in sufficient detail to quantifiably measure the impact of increased urban heating on air quality. The urban landscape impacts surface thermal energy exchanges that determine development of the UHI. This paper will illustrate how we are using high spatial remote sensing data collected over the Atlanta, Georgia metropolitan area in conjunction with other geographic information, to perform a detailed urban land cover classification and to determine the contribution of these land covers to the urban heat island effect. Also, the spatial arrangement of the land covers and the impact on urban heating from these selected patterns of development are evaluated. Additionally, this paper will show how these data are being used as inputs to improve air quality modeling for Atlanta, including potential benefits from UHI mitigation.

[General principles of urban ecological land classification and planning].

PubMed

Deng, Xiaowen; Sun, Yichao; Han, Shijie

2005-10-01

Urban ecological land planning is a difficult and urgent task in city layout. This paper presented the definition of urban ecological land, and according the definition, divided the urban ecological land into two groups, i. e., ecological land for service, and ecological land for functioning. Based on the principles of city layout, some measures to plan these two urban ecological land groups were proposed.

Enhanced Deep Blue Aerosol Retrieval Algorithm: The Second Generation

NASA Technical Reports Server (NTRS)

Hsu, N. C.; Jeong, M.-J.; Bettenhausen, C.; Sayer, A. M.; Hansell, R.; Seftor, C. S.; Huang, J.; Tsay, S.-C.

2013-01-01

The aerosol products retrieved using the MODIS collection 5.1 Deep Blue algorithm have provided useful information about aerosol properties over bright-reflecting land surfaces, such as desert, semi-arid, and urban regions. However, many components of the C5.1 retrieval algorithm needed to be improved; for example, the use of a static surface database to estimate surface reflectances. This is particularly important over regions of mixed vegetated and non- vegetated surfaces, which may undergo strong seasonal changes in land cover. In order to address this issue, we develop a hybrid approach, which takes advantage of the combination of pre-calculated surface reflectance database and normalized difference vegetation index in determining the surface reflectance for aerosol retrievals. As a result, the spatial coverage of aerosol data generated by the enhanced Deep Blue algorithm has been extended from the arid and semi-arid regions to the entire land areas.

Spatio-temporal variability of urban heat islands in local climate zones of Delhi-NCR

NASA Astrophysics Data System (ADS)

Budhiraja, Bakul; Pathak, Prasad; Agrawal, Girish

2017-10-01

Land use change is at the nexus of human territory expansion and urbanization. Human intrusion disturbs the natural heat energy balance of the area, although a new equilibrium of energy flux is attained but with greater diurnal range and adversely affecting the geo/physical variables. Modification in the trend of these variables causes a phenomenon known as Urban Heat Island (UHI) i.e. a dome of heat is formed around the city which has 7-10 °C high temperature than the nearby rural area at night. The study focuses on Surface UHI conventionally studied using thermal band of the remotely sensed satellite images. Land Surface Temperature (LST) is determined for the year 2015 using Landsat 8 for Delhi National Capital Region (NCR). This region was chosen because it is the biggest urban agglomeration in India, many satellite cities are coming in periphery and it has temperate climate. Quantification of UHI is predictably done using UHI intensity that is the difference between representative Urban and rural temperature. Recently the definition of urban and rural has been questioned because of various kinds of configurations of urban spaces across the globe. Delhi NCR urban configurations vary spatially- thus one UHI intensity does not give a deep understanding of the micro-climate. Advancement was made recently to standardize UHI intensity by dividing city into Local Climate Zones (LCZ), comes with 17 broad categories. LCZ map of Delhi NCR has been acquired from World Urban Database. The seasonality in LST across LCZ has been determined along with identifying warmest and coolest LCZ.

Bias Correction of MODIS AOD using DragonNET to obtain improved estimation of PM2.5

NASA Astrophysics Data System (ADS)

Gross, B.; Malakar, N. K.; Atia, A.; Moshary, F.; Ahmed, S. A.; Oo, M. M.

2014-12-01

MODIS AOD retreivals using the Dark Target algorithm is strongly affected by the underlying surface reflection properties. In particular, the operational algorithms make use of surface parameterizations trained on global datasets and therefore do not account properly for urban surface differences. This parameterization continues to show an underestimation of the surface reflection which results in a general over-biasing in AOD retrievals. Recent results using the Dragon-Network datasets as well as high resolution retrievals in the NYC area illustrate that this is even more significant at the newest C006 3 km retrievals. In the past, we used AERONET observation in the City College to obtain bias-corrected AOD, but the homogeneity assumptions using only one site for the region is clearly an issue. On the other hand, DragonNET observations provide ample opportunities to obtain better tuning the surface corrections while also providing better statistical validation. In this study we present a neural network method to obtain bias correction of the MODIS AOD using multiple factors including surface reflectivity at 2130nm, sun-view geometrical factors and land-class information. These corrected AOD's are then used together with additional WRF meteorological factors to improve estimates of PM2.5. Efforts to explore the portability to other urban areas will be discussed. In addition, annual surface ratio maps will be developed illustrating that among the land classes, the urban pixels constitute the largest deviations from the operational model.

Driving factors of urban land growth in Guangzhou and its implications for sustainable development

NASA Astrophysics Data System (ADS)

Cui, Xuezhu; Li, Shaoying; Wang, Xuetong; Xue, Xiaolong

2018-04-01

Since 2000, China's urban land has expanded at a dramatic speed because of the country's rapid urbanization. The country has been experiencing unbalanced development between rural and urban areas, causing serious challenges such as agricultural security and land resources waste. Effectively evaluating the driving factors of urban land growth is essential for improving efficient land use management and sustainable urban development. This study established a principal component regression model based on eight indicators to identify their influences on urban land growth in Guangzhou. The results provided a grouping analysis of the driving factors, and found that economic growth, urban population, and transportation development are the driving forces of urban land growth of Guangzhou, while the tertiary industry has an opposite effect. The findings led to further suggestions and recommendations for urban sustainable development. Hence, local governments should design relevant policies for achieving the rational development of urban land use and strategic planning on urban sustainable development.

Trends of urban surface temperature and heat island characteristics in the Mediterranean

NASA Astrophysics Data System (ADS)

Benas, Nikolaos; Chrysoulakis, Nektarios; Cartalis, Constantinos

2017-11-01

Urban air temperature studies usually focus on the urban canopy heat island phenomenon, whereby the city center experiences higher near surface air temperatures compared to its surrounding non-urban areas. The Land Surface Temperature (LST) is used instead of urban air temperature to identify the Surface Urban Heat Island (SUHI). In this study, the nighttime LST and SUHI characteristics and trends in the seventeen largest Mediterranean cities were investigated, by analyzing satellite observations for the period 2001-2012. SUHI averages and trends were based on an innovative approach of comparing urban pixels to randomly selected non-urban pixels, which carries the potential to better standardize satellite-derived SUHI estimations. A positive trend for both LST and SUHI for the majority of the examined cities was documented. Furthermore, a 0.1 °C decade-1 increase in urban LST corresponded to an increase in SUHI by about 0.04 °C decade-1. A longitudinal differentiation was found in the urban LST trends, with higher positive values appearing in the eastern Mediterranean. Examination of urban infrastructure and development factors during the same period revealed correlations with SUHI trends, which can be used to explain differences among cities. However, the majority of the cities examined show considerably increased trends in terms of the enhancement of SUHI. These findings are considered important so as to promote sustainable urbanization, as well as to support the development of heat island adaptation and mitigation plans in the Mediterranean.

Improving surface-subsurface water budgeting for Brownfield study sites using high resolution satellite imagery

NASA Astrophysics Data System (ADS)

Dujardin, J.; Boel, S.; Anibas, C.; Batelaan, O.; Canters, F.

2009-04-01

Countries around the world have problems with contaminated brownfield sites as resulting from a relatively anarchic economical and industrial development during the 19th and 20th centuries. Since a few decades policy makers and stakeholders have become more aware of the risk posed by these sites because some of these sites present direct public hazards. Water is often the main vector of the mobility of contaminants. In order to propose remediation measures for the contaminated sites, it is required to describe and to quantify as accurately as possible the surface and subsurface water fluxes in the polluted site. In this research a modelling approach with integrated remote sensing analysis has been developed for accurately calculating water and contaminant fluxes on the polluted sites. Groundwater pollution in urban environments is linked to patterns of land use, so to identify the sources of contamination with great accuracy in urban environments it is essential to characterize the land cover in a detailed way. The use of high resolution spatial information is required because of the complexity of the urban land use. An object-oriented classification approach applied on high resolution satellite data has been adopted. Cluster separability analysis and visual interpretation of the image objects belonging to each cluster resulted in the selection of 8 land-cover categories (water, bare soil, meadow, mixed forest, grey urban surfaces, red roofs, bright roofs and shadow).To assign the image objects to one of the 8 selected classes a multiple layer perceptron (MLP) approach was adopted, using the NeuralWorks Predict software. After a post-classification shadow removal and a rule-based classification enhancement a kappa-value of 0.86 was obtained. Once the land cover was characterized, the groundwater recharge has been simulated using the spatially distributed WetSpass model and the subsurface water flow was simulated with GMS 6.0 in order to identify and budget the water fluxes on the brownfield. The obtained land use map shows to have a strong impact on the groundwater recharge, resulting in a high spatial variability. Simulated groundwater fluxes from brownfield to a receiving river where independently verified by measurements and simulation of groundwater-surface water interaction based on thermal gradients in the river bed. It is concluded that in order to better quantify total fluxes of contaminants from brownfields in the groundwater, remote sensing imagery can be operationally integrated in a modelling procedure. The developed methodology is applied to a case site in Vilvoorde, Brussels (Belgium).

Regional Climate Modeling over the Marmara Region, Turkey, with Improved Land Cover Data

NASA Astrophysics Data System (ADS)

Sertel, E.; Robock, A.

2007-12-01

Land surface controls the partitioning of available energy at the surface between sensible and latent heat,and controls partitioning of available water between evaporation and runoff. Current land cover data available within the regional climate models such as Regional Atmospheric Modeling System (RAMS), the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) and Weather Research and Forecasting (WRF) was obtained from 1- km Advanced Very High Resolution Radiometer satellite images spanning April 1992 through March 1993 with an unsupervised classification technique. These data are not up-to-date and are not accurate for all regions and some land cover types such as urban areas. Here we introduce new, up-to-date and accurate land cover data for the Marmara Region, Turkey derived from Landsat Enhanced Thematic Mapper images into the WRF regional climate model. We used several image processing techniques to create accurate land cover data from Landsat images obtained between 2001 and 2005. First, all images were atmospherically and radiometrically corrected to minimize contamination effects of atmospheric particles and systematic errors. Then, geometric correction was performed for each image to eliminate geometric distortions and define images in a common coordinate system. Finally, unsupervised and supervised classification techniques were utilized to form the most accurate land cover data yet for the study area. Accuracy assessments of the classifications were performed using error matrix and kappa statistics to find the best classification results. Maximum likelihood classification method gave the most accurate results over the study area. We compared the new land cover data with the default WRF land cover data. WRF land cover data cannot represent urban areas in the cities of Istanbul, Izmit, and Bursa. As an example, both original satellite images and new land cover data showed the expansion of urban areas into the Istanbul metropolitan area, but in the WRF land cover data only a limited area along the Bosporus is shown as urban. In addition, the new land cover data indicate that the northern part of Istanbul is covered by evergreen and deciduous forest (verified by ground truth data), but the WRF data indicate that most of this region is croplands. In the northern part of the Marmara Region, there is bare ground as a result of open mining activities and this class can be identified in our land cover data, whereas the WRF data indicated this region as woodland. We then used this new data set to conduct WRF simulations for one main and two nested domains, where the inner-most domain represents the Marmara Region with 3 km horizontal resolution. The vertical domain of both main and nested domains extends over 28 vertical levels. Initial and boundary conditions were obtained from National Centers for Environmental Prediction-Department of Energy Reanalysis II and the Noah model was selected as the land surface model. Two model simulations were conducted; one with available land cover data and one with the newly created land cover data. Using detailed meteorological station data within the study area, we find that the simulation with the new land cover data set produces better temperature and precipitation simulations for the region, showing the value of accurate land cover data and that changing land cover data can be an important influence on local climate change.

A remotely sensed index of deforestation/urbanization for use in climate models

NASA Technical Reports Server (NTRS)

Gillies, Robert R.; Carlson, Toby N.

1995-01-01

The object of this research is to use indirect measurements, notably thermal infrared, to describe urbanization and deforestation with parameters that can be used to assess, as well as predict, the effects of land use changes on local microclimate. More specifically, we use a new approach for the treatment of remotely sensed data; this is referred to as the 'triangle' method. The name triangle is given because the envelope of data points, when plotted as a function of surface radiant temperature versus vegetation index or fractional vegetation cover, exhibits the shape of a triangle. From the information contained on these 'scatter plots', land use changes can be related to two intrinsic surface variables, the surface moisture availability (M(sub 0))(sup 1) and fractional vegetation cover. Recent work by Carlson et al. indicate that the triangle shape on the scatter plots may be scale similar, suggesting that these two parameters are subject to the same interpretation on differing scales. A second objective in this research is to determine if historical data for Advanced Very High Resolution Radiometer (AVHRR) (NOAA satellite; 1.1 km resolution at nadir) can be used to assess changes in regional land use over time. To this end, two target areas were chosen for the investigation of urbanization and two for deforestation. The former comprise tow areas in Pennsylvania, one a small but rapidly growing population center (State College) and the other a medium-sized urban area which continues to undergo development (Chester County). The two deforestation sites consist of rain forest areas in western and central Costa Rica and a region in the Brazilian Amazon.

Application of spatially gridded temperature and land cover data sets for urban heat island analysis

USGS Publications Warehouse

Gallo, Kevin; Xian, George Z.

2014-01-01

Two gridded data sets that included (1) daily mean temperatures from 2006 through 2011 and (2) satellite-derived impervious surface area, were combined for a spatial analysis of the urban heat-island effect within the Dallas-Ft. Worth Texas region. The primary advantage of using these combined datasets included the capability to designate each 1 × 1 km grid cell of available temperature data as urban or rural based on the level of impervious surface area within the grid cell. Generally, the observed differences in urban and rural temperature increased as the impervious surface area thresholds used to define an urban grid cell were increased. This result, however, was also dependent on the size of the sample area included in the analysis. As the spatial extent of the sample area increased and included a greater number of rural defined grid cells, the observed urban and rural differences in temperature also increased. A cursory comparison of the spatially gridded temperature observations with observations from climate stations suggest that the number and location of stations included in an urban heat island analysis requires consideration to assure representative samples of each (urban and rural) environment are included in the analysis.

Estimation of urban surface water at subpixel level from neighborhood pixels using multispectral remote sensing image (Conference Presentation)

NASA Astrophysics Data System (ADS)

Xie, Huan; Luo, Xin; Xu, Xiong; Wang, Chen; Pan, Haiyan; Tong, Xiaohua; Liu, Shijie

2016-10-01

Water body is a fundamental element in urban ecosystems and water mapping is critical for urban and landscape planning and management. As remote sensing has increasingly been used for water mapping in rural areas, this spatially explicit approach applied in urban area is also a challenging work due to the water bodies mainly distributed in a small size and the spectral confusion widely exists between water and complex features in the urban environment. Water index is the most common method for water extraction at pixel level, and spectral mixture analysis (SMA) has been widely employed in analyzing urban environment at subpixel level recently. In this paper, we introduce an automatic subpixel water mapping method in urban areas using multispectral remote sensing data. The objectives of this research consist of: (1) developing an automatic land-water mixed pixels extraction technique by water index; (2) deriving the most representative endmembers of water and land by utilizing neighboring water pixels and adaptive iterative optimal neighboring land pixel for respectively; (3) applying a linear unmixing model for subpixel water fraction estimation. Specifically, to automatically extract land-water pixels, the locally weighted scatter plot smoothing is firstly used to the original histogram curve of WI image . And then the Ostu threshold is derived as the start point to select land-water pixels based on histogram of the WI image with the land threshold and water threshold determination through the slopes of histogram curve . Based on the previous process at pixel level, the image is divided into three parts: water pixels, land pixels, and mixed land-water pixels. Then the spectral mixture analysis (SMA) is applied to land-water mixed pixels for water fraction estimation at subpixel level. With the assumption that the endmember signature of a target pixel should be more similar to adjacent pixels due to spatial dependence, the endmember of water and land are determined by neighboring pure land or pure water pixels within a distance. To obtaining the most representative endmembers in SMA, we designed an adaptive iterative endmember selection method based on the spatial similarity of adjacent pixels. According to the spectral similarity in a spatial adjacent region, the spectrum of land endmember is determined by selecting the most representative land pixel in a local window, and the spectrum of water endmember is determined by calculating an average of the water pixels in the local window. The proposed hierarchical processing method based on WI and SMA (WISMA) is applied to urban areas for reliability evaluation using the Landsat-8 Operational Land Imager (OLI) images. For comparison, four methods at pixel level and subpixel level were chosen respectively. Results indicate that the water maps generated by the proposed method correspond as closely with the truth water maps with subpixel precision. And the results showed that the WISMA achieved the best performance in water mapping with comprehensive analysis of different accuracy evaluation indexes (RMSE and SE).

Evaluation of urban surface parameterizations in the WRF model using measurements during the Texas Air Quality Study 2006 field campaign

NASA Astrophysics Data System (ADS)

Lee, S.-H.; Kim, S.-W.; Angevine, W. M.; Bianco, L.; McKeen, S. A.; Senff, C. J.; Trainer, M.; Tucker, S. C.; Zamora, R. J.

2010-10-01

The impact of urban surface parameterizations in the WRF (Weather Research and Forecasting) model on the simulation of local meteorological fields is investigated. The Noah land surface model (LSM), a modified LSM, and a single-layer urban canopy model (UCM) have been compared, focusing on urban patches. The model simulations were performed for 6 days from 12 August to 17 August during the Texas Air Quality Study 2006 field campaign. Analysis was focused on the Houston-Galveston metropolitan area. The model simulated temperature, wind, and atmospheric boundary layer (ABL) height were compared with observations from surface meteorological stations (Continuous Ambient Monitoring Stations, CAMS), wind profilers, the NOAA Twin Otter aircraft, and the NOAA Research Vessel Ronald H. Brown. The UCM simulation showed better results in the comparison of ABL height and surface temperature than the LSM simulations, whereas the original LSM overestimated both the surface temperature and ABL height significantly in urban areas. The modified LSM, which activates hydrological processes associated with urban vegetation mainly through transpiration, slightly reduced warm and high biases in surface temperature and ABL height. A comparison of surface energy balance fluxes in an urban area indicated the UCM reproduces a realistic partitioning of sensible heat and latent heat fluxes, consequently improving the simulation of urban boundary layer. However, the LSMs have a higher Bowen ratio than the observation due to significant suppression of latent heat flux. The comparison results suggest that the subgrid heterogeneity by urban vegetation and urban morphological characteristics should be taken into account along with the associated physical parameterizations for accurate simulation of urban boundary layer if the region of interest has a large fraction of vegetation within the urban patch. Model showed significant discrepancies in the specific meteorological conditions when nocturnal low-level jets exist and a thermal internal boundary layer over water forms.

Dominant control of agriculture and irrigation on urban heat island in India.

PubMed

Kumar, Rahul; Mishra, Vimal; Buzan, Jonathan; Kumar, Rohini; Shindell, Drew; Huber, Matthew

2017-10-25

As is true in many regions, India experiences surface Urban Heat Island (UHI) effect that is well understood, but the causes of the more recently discovered Urban Cool Island (UCI) effect remain poorly constrained. This raises questions about our fundamental understanding of the drivers of rural-urban environmental gradients and hinders development of effective strategies for mitigation and adaptation to projected heat stress increases in rapidly urbanizing India. Here we show that more than 60% of Indian urban areas are observed to experience a day-time UCI. We use satellite observations and the Community Land Model (CLM) to identify the impact of irrigation and prove for the first time that UCI is caused by lack of vegetation and moisture in non-urban areas relative to cities. In contrast, urban areas in extensively irrigated landscapes generally experience the expected positive UHI effect. At night, UHI warming intensifies, occurring across a majority (90%) of India's urban areas. The magnitude of rural-urban temperature contrasts is largely controlled by agriculture and moisture availability from irrigation, but further analysis of model results indicate an important role for atmospheric aerosols. Thus both land-use decisions and aerosols are important factors governing, modulating, and even reversing the expected urban-rural temperature gradients.

Associations among land-use, habitat characteristics, and invertebrate community structure in nine streams on the island of Oahu, Hawaii

USGS Publications Warehouse

Brasher, Anne M.D.; Wolff, Reuben H.; Luton, Corene D.

2003-01-01

The island of Oahu is one of 51 study units established as part of the U.S. Geological Surveys National Water-Quality Assessment (NAWQA) program to assess the status and trends of the Nations surface and ground-water resources, and to link status and trends with an understanding of the natural and human factors that affect water quality. As part of the NAWQA program, benthic invertebrate communities were surveyed at ten sites in nine streams representing the three main types of land use on Oahu: urban, agriculture, and forested. At each sampling site, habitat characteristics were determined at a range of spatial scales including drainage basin, segment, reach, transect, and point. Associations among land use, habitat characteristics, and benthic invertebrate community structure were examined. The rapid population growth and increasing urbanization on Oahu has resulted in substantial stream habitat alteration. Instream habitat characteristics at the urban and mixed (urban and agriculture) land-use sites were markedly different from those at the forested sites. Urban and mixed land-use sites, most of which were channelized, tended to have less riparian vegetation, higher water temperatures, smaller substrate, and higher levels of embeddedness and siltation than sites in forested watersheds. The majority of invertebrate taxa identified during this study were non-native. Invertebrate abundance was lower at urban and mixed land-use sites than at forested sites, while species richness (the number of different species) showed the opposite pattern. Multivariate analyses indicated that invertebrate species composition was similar at sites with similar land use. Aquatic insects of the orders Diptera and Trichoptera were the most common insects in all samples. The ratio of Diptera to Trichoptera abundance varied with urbanization. Forested sites were dominated by Trichoptera, and urban and mixed land-use sites were dominated by Diptera. Molluscs typically occurred in channelized urban streams although no native molluscs were collected during this study. The most abundant molluscs were pan-tropical thiarid snails, the introduced clam Corbicula fluminea, and the limpet Ferrissia sharpi. Two native and four introduced species of Crustacea were collected at the sampling sites. To effectively manage Hawaiian watersheds for native species and the communities they form, the ways in which these species respond to human-induced changes needs to be understood. This report provides important information describing the usefulness of invertebrates as indicators of stream quality conditions and how an integrated assessment of stream quality will allow for the development of appropriate monitoring and management strategies.

Analysis of Global Urban Temperature Trends and Urbanization Impacts

NASA Astrophysics Data System (ADS)

Lee, K. I.; Ryu, J.; Jeon, S. W.

2018-04-01

Due to urbanization, urban areas are shrinking green spaces and increasing concrete, asphalt pavement. So urban climates are different from non-urban areas. In addition, long-term macroscopic studies of urban climate change are becoming more important as global urbanization affects global warming. To do this, it is necessary to analyze the effect of urbanization on the temporal change in urban temperature with the same temperature data and standards for urban areas around the world. In this study, time series analysis was performed with the maximum, minimum, mean and standard values of surface temperature during the from 1980 to 2010 and analyzed the effect of urbanization through linear regression analysis with variables (population, night light, NDVI, urban area). As a result, the minimum value of the surface temperature of the urban area reflects an increase by a rate of 0.28K decade-1 over the past 31 years, the maximum value reflects an increase by a rate of 0.372K decade-1, the mean value reflects an increase by a rate of 0.208 decade-1, and the standard deviation reflects a decrease by rate of 0.023K decade-1. And the change of surface temperature in urban areas is affected by urbanization related to land cover such as decrease of greenery and increase of pavement area, but socioeconomic variables are less influential than NDVI in this study. This study are expected to provide an approach to future research and policy-planning for urban temperature change and urbanization impacts.

Comparing the diurnal and seasonal variabilities of atmospheric and surface urban heat islandsbased on the Beijing urban meteorological network

NASA Astrophysics Data System (ADS)

Jiang, S.; Wang, K.; Wang, J.; Zhou, C.; Wang, X.; Lee, X.

2017-12-01

This study compared the diurnal and seasonal cycles of atmospheric and surface urban heat islands (UHIs) based on hourly air temperatures (Ta) collected at 65 out of 262 stations in Beijing and land surface temperature (Ts) derived from Moderate Resolution Imaging Spectroradiometer in the years 2013-2014. We found that the nighttime atmospheric and surface UHIs referenced to rural cropland stations exhibited significant seasonal cycles, with the highest in winter. However, the seasonal variations in the nighttime UHIs referenced to mountainous forest stations were negligible, because mountainous forests have a higher nighttime Ts in winter and a lower nighttime T a in summer than rural croplands. Daytime surface UHIs showed strong seasonal cycles, with the highest in summer. The daytime atmospheric UHIs exhibited a similar but less seasonal cycle under clear-sky conditions, which was not apparent under cloudy-sky conditions. Atmospheric UHIs in urban parks were higher in daytime. Nighttime atmospheric UHIs are influenced by energy stored in urban materials during daytime and released during nighttime. The stronger anthropogenic heat release in winter causes atmospheric UHIs to increase with time during winter nights, but decrease with time during summer nights. The percentage of impervious surfaces is responsible for 49%-54% of the nighttime atmospheric UHI variability and 31%-38% of the daytime surface UHI variability. However, the nighttime surface UHI was nearly uncorrelated with the percentage of impervious surfaces around the urban stations.

Dynamic analysis and ecological evaluation of urban heat islands in Raipur city, India

NASA Astrophysics Data System (ADS)

Guha, Subhanil; Govil, Himanshu; Mukherjee, Sandip

2017-07-01

Spatial-temporal distribution of the urban heat islands (UHI) and their changes over Raipur city have been analyzed using multitemporal Landsat satellite data from 1995 to 2016. Land surface temperature (LST) was retrieved through a mono-window algorithm. Some selected land use/land cover (LU-LC) indices were analyzed with LST using linear regression. The urban thermal field variance index (UTFVI) was applied to measure the thermal comfort level of the city. Results show that during the observed period, the study area experienced a gradual increasing rate in mean LST (>1% per annum). The UHI developed especially along the north-western industrial area and south-eastern bare land of the city. A difference in mean LST between UHI and non-UHI for different time periods (2.6°C in 1995, 2.85°C in 2006, 3.42°C in 2009, and 3.63°C in 2016) reflects the continuous warming status of the city. The LST map also shows the existence of a few urban hot spots near the industrial areas, metal roofs, and high density transport parking lots, which are more abundant in the north-western part of the city. The UTFVI map associated with UHI indicates that the inner parts of the city are ecologically more comfortable than the outer peripheries.

The urban boundary-layer field campaign in marseille (ubl/clu-escompte): set-up and first results

NASA Astrophysics Data System (ADS)

Mestayer, P.G.; Durand, P.; Augustin, P.; Bastin, S.; Bonnefond, J.-M.; Benech, B.; Campistron, B.; Coppalle, A.; Delbarre, H.; Dousset, B.; Drobinski, P.; Druilhet, A.; Frejafon, E.; Grimmond, C.S.B.; Groleau, D.; Irvine, M.; Kergomard, C.; Kermadi, S.; Lagouarde, J.-P.; Lemonsu, A.; Lohou, F.; Long, N.; Masson, V.; Moppert, C.; Noilhan, J.; Offerle, B.; Oke, T.R.; Pigeon, G.; Puygrenier, V.; Roberts, S.; Rosant, J.-M.; Sanid, F.; Salmond, J.; Talbaut, M.; Voogt, J.

The UBL/CLU (urban boundary layer/couche limite urbaine) observation and modelling campaign is a side-project of the regional photochemistry campaign ESCOMPTE. UBL/CLU focuses on the dynamics and thermodynamics of the urban boundary layer of Marseille, on the Mediterranean coast of France. The objective of UBL/CLU is to document the four-dimensional structure of the urban boundary layer and its relation to the heat and moisture exchanges between the urban canopy and the atmosphere during periods of low wind conditions, from June 4 to July 16, 2001. The project took advantage of the comprehensive observational set-up of the ESCOMPTE campaign over the Berre-Marseille area, especially the ground-based remote sensing, airborne measurements, and the intensive documentation of the regional meteorology. Additional instrumentation was installed as part of UBL/CLU. Analysis objectives focus on (i) validation of several energy balance computational schemes such as LUMPS, TEB and SM2-U, (ii) ground truth and urban canopy signatures suitable for the estimation of urban albedos and aerodynamic surface temperatures from satellite data, (iii) high resolution mapping of urban land cover, land-use and aerodynamic parameters used in UBL models, and (iv) testing the ability of high resolution atmospheric models to simulate the structure of the UBL during land and sea breezes, and the related transport and diffusion of pollutants over different districts of the city. This paper presents initial results from such analyses and details of the overall experimental set-up.

High-quality observation of surface imperviousness for urban runoff modelling using UAV imagery

NASA Astrophysics Data System (ADS)

Tokarczyk, P.; Leitao, J. P.; Rieckermann, J.; Schindler, K.; Blumensaat, F.

2015-10-01

Modelling rainfall-runoff in urban areas is increasingly applied to support flood risk assessment, particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the catchment area as model input. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increases as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data are often unavailable. Modern unmanned aerial vehicles (UAVs) allow one to acquire high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility of deriving high-resolution imperviousness maps for urban areas from UAV imagery and of using this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is proposed and evaluated in a state-of-the-art urban drainage modelling exercise. In a real-life case study (Lucerne, Switzerland), we compare imperviousness maps generated using a fixed-wing consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo). After assessing their overall accuracy, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyse the surface runoff of the 307 individual subcatchments regarding relevant attributes, such as peak runoff and runoff volume. Finally, we evaluate the model's channel flow prediction performance through a cross-comparison with reference flow measured at the catchment outlet. We show that imperviousness maps generated from UAV images processed with modern classification methods achieve an accuracy comparable to standard, off-the-shelf aerial imagery. In the examined case study, we find that the different imperviousness maps only have a limited influence on predicted surface runoff and pipe flows, when traditional workflows are used. We expect that they will have a substantial influence when more detailed modelling approaches are employed to characterize land use and to predict surface runoff. We conclude that UAV imagery represents a valuable alternative data source for urban drainage model applications due to the possibility of flexibly acquiring up-to-date aerial images at a quality compared with off-the-shelf image products and a competitive price at the same time. We believe that in the future, urban drainage models representing a higher degree of spatial detail will fully benefit from the strengths of UAV imagery.

Sediment sources in an urbanizing, mixed land-use watershed

NASA Astrophysics Data System (ADS)

Nelson, Erin J.; Booth, Derek B.

2002-07-01

The Issaquah Creek watershed is a rapidly urbanizing watershed of 144 km 2 in western Washington, where sediment aggradation of the main channel and delivery of fine sediment into a large downstream lake have raised increasingly frequent concerns over flooding, loss of fish habitat, and degraded water quality. A watershed-scale sediment budget was evaluated to determine the relative effects of land-use practices, including urbanization, on sediment supply and delivery, and to guide management responses towards the most effective source-reduction strategies. Human activity in the watershed, particularly urban development, has caused an increase of nearly 50% in the annual sediment yield, now estimated to be 44 tonnes km -2 yr -1. The main sources of sediment in the watershed are landslides (50%), channel-bank erosion (20%), and road-surface erosion (15%). This assessment characterizes the role of human activity in mixed-use watersheds such as this, and it demonstrates some of the key processes, particularly enhanced stream-channel erosion, by which urban development alters sediment loads.

Estimation of Land Surface Temperature for the Quantitative Analysis of Land Cover of Lower Areas of Sindh to Assess the Impacts of Climate Variability

NASA Astrophysics Data System (ADS)

Qaisar, Maha

2016-07-01

Due to the present land use practices and climate variability, drastic shifts in regional climate and land covers are easily seen and their future reduction and gain are too well predicted. Therefore, there is an increasing need for data on land-cover changes at narrow and broad spatial scales. In this study, a remote sensing-based technique for land-cover-change analysis is applied to the lower Sindh areas for the last decade. Landsat satellite products were analyzed on an alternate yearly basis, from 1990 to 2016. Then Land-cover-change magnitudes were measured and mapped for alternate years. Land Surface Temperature (LST) is one of the critical elements in the natural phenomena of surface energy and water balance at local and global extent. However, LST was computed by using Landsat thermal bands via brightness temperature and a vegetation index. Normalized difference vegetation index (NDVI) was interpreted and maps were achieved. LST reflected NDVI patterns with complexity of vegetation patterns. Along with this, Object Based Image Analysis (OBIA) was done for classifying 5 major classes of water, vegetation, urban, marshy lands and barren lands with significant map layouts. Pakistan Meteorological Department provided the climate data in which rainfall, temperature and air temperature are included. Once the LST and OBIA are performed, overlay analysis was done to correlate the results of LST with OBIA and LST with meteorological data to ascertain the changes in land covers due to increasing centigrade of LST. However, satellite derived LST was also correlated with climate data for environmental analysis and to estimate Land Surface Temperature for assessing the inverse impacts of climate variability. This study's results demonstrate the land-cover changes in Lower Areas of Sindh including the Indus Delta mostly involve variations in land-cover conditions due to inter-annual climatic variability and temporary shifts in seasonality. However it is too concluded that transitory alteration of the biophysical characteristics of the surface driven by variations in rainfall is the prevailing progression. Moreover, future work will focus on finer-scale analysis and validations of patterns of changes due to rapid urbanization and population explosion in poverty stricken areas of Sindh which are posing an adverse impact on the land utilization and in turn increasing the land surface temperature and ultimately more stress on the low lying areas of Sindh i.e. Indus Delta will be losing its productivity and capacity to bear biodiversity whether the fauna or flora. Hence, this regional scale problem will become a global concern. Therefore, it is needed to stop the menace in its starting phase to mitigate the problem and to bring minds on this horrendous situation.

Construction and Analysis of Long-Term Surface Temperature Dataset in Fujian Province

NASA Astrophysics Data System (ADS)

Li, W. E.; Wang, X. Q.; Su, H.

2017-09-01

Land surface temperature (LST) is a key parameter of land surface physical processes on global and regional scales, linking the heat fluxes and interactions between the ground and atmosphere. Based on MODIS 8-day LST products (MOD11A2) from the split-window algorithms, we constructed and obtained the monthly and annual LST dataset of Fujian Province from 2000 to 2015. Then, we analyzed the monthly and yearly time series LST data and further investigated the LST distribution and its evolution features. The average LST of Fujian Province reached the highest in July, while the lowest in January. The monthly and annual LST time series present a significantly periodic features (annual and interannual) from 2000 to 2015. The spatial distribution showed that the LST in North and West was lower than South and East in Fujian Province. With the rapid development and urbanization of the coastal area in Fujian Province, the LST in coastal urban region was significantly higher than that in mountainous rural region. The LST distributions might affected by the climate, topography and land cover types. The spatio-temporal distribution characteristics of LST could provide good references for the agricultural layout and environment monitoring in Fujian Province.

Simulating Urban Tree Effects on Air, Water, and Heat Pollution Mitigation: iTree-Hydro Model

NASA Astrophysics Data System (ADS)

Yang, Y.; Endreny, T. A.; Nowak, D.

2011-12-01

Urban and suburban development changes land surface thermal, radiative, porous, and roughness properties and pollutant loading rates, with the combined effect leading to increased air, water, and heat pollution (e.g., urban heat islands). In this research we present the USDA Forest Service urban forest ecosystem and hydrology model, iTree Eco and Hydro, used to analyze how tree cover can deliver valuable ecosystem services to mitigate air, water, and heat pollution. Air pollution mitigation is simulated by dry deposition processes based on detected pollutant levels for CO, NO2, SO2, O3 and atmospheric stability and leaf area indices. Water quality mitigation is simulated with event mean concentration loading algorithms for N, P, metals, and TSS, and by green infrastructure pollutant filtering algorithms that consider flow path dispersal areas. Urban cooling considers direct shading and indirect evapotranspiration. Spatially distributed estimates of hourly tree evapotranspiration during the growing season are used to estimate human thermal comfort. Two main factors regulating evapotranspiration are soil moisture and canopy radiation. Spatial variation of soil moisture is represented by a modified urban topographic index and radiation for each tree is modified by considering aspect, slope and shade from surrounding buildings or hills. We compare the urban cooling algorithms used in iTree-Hydro with the urban canopy and land surface physics schemes used in the Weather Research and Forecasting model. We conclude by identifying biophysical feedbacks between tree-modulated air and water quality environmental services and how these may respond to urban heating and cooling. Improvements to this iTree model are intended to assist managers identify valuable tree services for urban living.

The complexities of urban flood response: Flood frequency analyses for the Charlotte metropolitan region

NASA Astrophysics Data System (ADS)

Zhou, Zhengzheng; Smith, James A.; Yang, Long; Baeck, Mary Lynn; Chaney, Molly; Ten Veldhuis, Marie-Claire; Deng, Huiping; Liu, Shuguang

2017-08-01

We examine urban flood response through data-driven analyses for a diverse sample of "small" watersheds (basin scale ranging from 7.0 to 111.1 km2) in the Charlotte Metropolitan region. These watersheds have experienced extensive urbanization and suburban development since the 1960s. The objective of this study is to develop a broad characterization of land surface and hydrometeorological controls of urban flood hydrology. Our analyses are based on peaks-over-threshold flood data developed from USGS streamflow observations and are motivated by problems of flood hazard characterization for urban regions. We examine flood-producing rainfall using high-resolution (1 km2 spatial resolution and 15 min time resolution), bias-corrected radar rainfall fields that are developed through the Hydro-NEXRAD system. The analyses focus on the 2001-2015 period. The results highlight the complexities of urban flood response. There are striking spatial heterogeneities in flood peak magnitudes, response times, and runoff ratios across the study region. These spatial heterogeneities are mainly linked to watershed scale, the distribution of impervious cover, and storm water management. Contrasting land surface properties also determine the mixture of flood-generating mechanisms for a particular watershed. Warm-season thunderstorm systems and tropical cyclones are main flood agents in Charlotte, with winter/spring storms playing a role in less-urbanized watersheds. The mixture of flood agents exerts a strong impact on the upper tail of flood frequency distributions. Antecedent watershed wetness plays a minor role in urban flood response, compared with less-urbanized watersheds. Implications for flood hazard characterization in urban watersheds and for advances in flood science are discussed.

Continental-scale Sensitivity of Water Yield to Changes in Impervious Cover

NASA Astrophysics Data System (ADS)

Caldwell, P.; Sun, G.; McNulty, S.; Cohen, E.; Moore Myers, J.

2012-12-01

Projected land conversion from native forest, grassland, and shrubland to urban impervious cover will alter watershed water balances by reducing groundwater recharge and evapotranspiration, increasing surface runoff, and potentially altering regional weather patterns. These hydrologic changes have important ecohydrological implications to local watersheds, including stream channel habitat degradation and the loss of aquatic biodiversity. Many observational studies have evaluated the impact of urbanization on water yield in small catchments downstream of specific urban areas. However it is often difficult to separate the impact of impervious cover from other impacts of urbanization such as leaking water infrastructure, irrigation runoff, water supply withdrawals, and effluent discharge. In addition, the impact of impervious cover has not been evaluated at scales large enough to assess spatial differences in water yield sensitivity to changes in impervious cover. The objective of this study was to assess the sensitivity of water yield to impervious cover across the conterminous U.S., and to identify locations where water yield will be most impacted by future urbanization. We used the Water Supply Stress Index (WaSSI) model to simulate monthly water yield as impacted by impervious cover for the approximately 82,000 12-digit HUC watersheds across the conterminous U.S. WaSSI computed infiltration, surface runoff, soil moisture, and baseflow processes explicitly for ten vegetative land cover classes and impervious cover in each watershed using the 2006 National Land Cover Dataset estimates of impervious cover. Our results indicate that impervious cover has increased total water yield in urban areas (relative to native vegetation), and that the increase was most significant during the growing season. The proportion of stream flow that occurred as baseflow decreased, even though total water yield increased as a result of impervious cover. Water yield was most sensitive to changes in impervious cover in areas where annual evapotranspiration is high relative to precipitation (e.g. the Southwestern States, Texas, and Florida). Water yield was less sensitive in areas with low evapotranspiration relative to precipitation (e.g. Pacific Northwest and Northeastern States). Additionally, water yield was most impacted when high evapotranspiration land cover types (e.g. forests) were converted to impervious cover than when lower evapotranspiration land cover types (e.g. grassland) were converted. Using projections of future impervious cover provided by the U.S. EPA Integrated Climate and Land Use Scenarios project, water yield in urban areas of the Southwest, Texas, and Florida will be the most impacted by 2050, in part because these areas are projected to have significant increases in impervious cover, but also because they are in areas where evapotranspiration is high relative to precipitation. Our study suggests that watershed management should consider the climate-driven sensitivity of water yield to increases in impervious cover and the type of land cover being converted in addition to the magnitude of projected increases in impervious cover when evaluating impacts of urbanization on water resources.

Conversion of prime agricultural land to urban land uses in Kansas City

NASA Technical Reports Server (NTRS)

Shaklee, R. V.

1976-01-01

In an expanding urban environment, agriculture and urban land uses are the two primary competitors for regional land resources. As a result of an increasing awareness of the effects which urban expansion has upon the regional environment, the conversion of prime agricultural land to urban land uses has become a point of concern to urban planners. A study was undertaken for the Kansas City Metropolitan Region, to determine the rate at which prime agricultural land has been converted to urban land uses over a five year period from 1969 to 1974. Using NASA high altitude color infrared imagery acquired over the city in October, 1969 and in May, 1974 to monitor the extent and location of urban expansion in the interim period, it was revealed that 42% of that expansion had occurred upon land classified as having prime agricultural potential. This involved a total of 10,727 acres of prime agricultural land and indicated a 7% increase over the 1969 which showed that 35% of the urban area had been developed on prime agricultural land.

The Use of ATLAS Data to Quantify Surface Radiative Budget Alteration Through Urbanization for San Juan, Puerto Rico.

NASA Technical Reports Server (NTRS)

Luvall, Jeffrey C.; Rickman, Douglas L.; Gonzalez, Jorge; Schiller, Steve

2006-01-01

The additional heating of the air over the city is the result of the replacement of naturally vegetated surfaces with those composed of asphalt, concrete, rooftops and other manmade materials. The temperatures of these artificial surfaces can be 20 to 40 0 C higher than vegetated surfaces. Materials such as asphalt store much of the sun s energy and remains hot long after sunset. This produces a dome of elevated air temperatures 5 to 8 C greater over the city, compared to the air temperatures over adjacent rural areas. This effect is called the "urban heat island". Urban landscapes are a complex mixture of vegetated and nonvegetated surfaces. It is difficult to take enough temperature measurements over a large city area to characterize the complexity of urban radiant surface temperature variability. However, the use of remotely sensed thermal data from airborne scanners are ideal for the task. The NASA Airborne Thermal and Land Applications Sensor (ATLAS) operates in the visual and IR bands was used in February 2004 to collect data from San Juan, Puerto Rico with the main objective of investigating the Urban Heat Island (UHI) in tropical cities. In this presentation we will examine the techniques of analyzing remotely sensed data for measuring the effect of various urban surfaces on their contribution to the urban heat island effect. Results from data collected from other US cities of Sacramento, Salt Lake City and Baton Rouge will be used to compare the "urban fabric" among the cities.

Quantifying the Influence of Urbanization on a Coastal Floodplain

NASA Astrophysics Data System (ADS)

Sebastian, A.; Juan, A.; Bedient, P. B.

2016-12-01

The U.S. Gulf Coast is the fastest growing region in the United States; between 1960 and 2010, the number of housing units along the Gulf of Mexico increased by 246%, vastly outpacing growth in other parts of the country (NOAA 2013). Numerous studies have shown that increases in impervious surface associated with urbanization reduce infiltration and increase surface runoff. While empirical evidence suggests that changes in land use are leading to increased flood damage in overland areas, earlier studies have largely focused on the impacts of urbanization on surface runoff and watershed hydrology, rather than quantifying its influence on the spatial extent of flooding. In this study, we conduct a longitudinal assessment of the evolution of flood risk since 1970 in an urbanizing coastal watershed. Utilizing the distributed hydrologic model, Vflo®, in combination with the hydraulic model, HEC-RAS, we quantify the impact of localized land use/land cover (LULC) change on the spatial extent of flooding in the watershed and the underlying flood hazard structure. The results demonstrate that increases in impervious cover between 1970 and 2010 (34%) and 2010 and 2040 (18%) increase the size of the floodplain by 26 and 17%, respectively. Furthermore, the results indicate that the depth and frequency of flooding in neighborhoods within the 1% floodplain have increased substantially (see attached figure). Finally, this analysis provides evidence that outdated FEMA floodplain maps could be underestimating the extent of the floodplain by upwards of 25%, depending on the rate of urbanization in the watershed; and, that by incorporating physics-based distributed hydrologic models into floodplain studies, floodplain maps can be easily updated to reflect the most recent LULC information available. The methods presented in this study have important implications for the development of mitigation strategies in coastal areas, such as deterring future development in flood prone areas and directing flood mitigation efforts in already flood prone communities. ReferencesNational Oceanic and Atmospheric Administration (NOAA). (2013). National Coastal Population Report: Population Trends from 1970 to 2020.

A geographical approach to tracking Escherichia coli and other water quality constituents in a Texas coastal plains watershed.

PubMed

Harclerode, C L; Gentry, T J; Aitkenhead-Peterson, J A

2013-06-01

Diffuse sources of surface water pathogens and nutrients can be difficult to isolate in larger river basins. This study used a geographical or nested approach to isolate diffuse sources of Escherichia coli and other water quality constituents in a 145.7-km(2) river basin in south central Texas, USA. Average numbers of E. coli ranged from 49 to 64,000 colony forming units (CFU) per 100 mL depending upon season and stream flow over the 1-year sampling period. Nitrate-N concentrations ranged from 48 to 14,041 μg L(-1) and orthophosphate-P from 27 to 2,721 μg L(-1). High concentrations of nitrate-N, dissolved organic nitrogen, and orthophosphate-P were observed downstream of waste water treatment plants but E. coli values were higher in a watershed draining an older part of the city. Total urban land use explained between 56 and 72 % of the variance in mean annual E. coli values (p < 0.05) in nine hydrologically disconnected creeks. Of the types of urban land use, commercial land use explained most of the variance in E. coli values in the fall and winter. Surface water sodium, alkalinity, and potassium concentrations in surface water were best described by the proportion of commercial land use in the watershed. Based on our nested approach in examining surface water, city officials are able to direct funding to specific areas of the basin in order to mitigate high surface water E. coli numbers and nutrient concentrations.

Assessment of urban heat Island for Craiova from satellite-based LST

NASA Astrophysics Data System (ADS)

Udristioiu, Mihaela Tinca; Velea, Liliana; Bojariu, Roxana; Sararu, Silviu Constantin

2017-12-01

The urban heat island is defined as an excess of heating in urban areas compared with surrounding rural zones which is illustrated by higher surface and air temperatures in the inner part of the cities. The aim of this study is to identify the UHI effect for Craiova - the largest city in the South-Western part of Romania - and to assess its intensity during summer. To this end, MODIS Land surface temperature (LST) for day and night for summer months (June, July, August), in the interval 2002-2017, as well as yearly Land Cover Type (LCT) data also from MODIS were employed. Furthermore, measurements of air and soil temperature from meteorological station Craiova, available from the National Meteorological Administration database, were used to investigate their relation with LST. The analysis shows that in the urban area of Craiova the long-term summer mean LST is about 4 °C (2 °C), higher than in the rural area during daytime (nighttime). During high temperatures episodes, the mean daytime LST reaches 45-47 °C in the city, while the difference from the rural surrounding area is of 2-3 °C. A high correlation (0.77-0.83) is found between LST and air temperature for all land-use types in the area considered. Both LST and 2m-air temperature time-series manifest an increasing linear tendency over the period considered, being more pronounced during the day.

On the Role of Urban and Vegetative Land Cover in the Identification of Tornado Damage Using Dual-Resolution Multispectral Satellite Imagery

NASA Astrophysics Data System (ADS)

Kingfield, D.; de Beurs, K.

2014-12-01

It has been demonstrated through various case studies that multispectral satellite imagery can be utilized in the identification of damage caused by a tornado through the change detection process. This process involves the difference in returned surface reflectance between two images and is often summarized through a variety of ratio-based vegetation indices (VIs). Land cover type plays a large contributing role in the change detection process as the reflectance properties of vegetation can vary based on several factors (e.g. species, greenness, density). Consequently, this provides the possibility for a variable magnitude of loss, making certain land cover regimes less reliable in the damage identification process. Furthermore, the tradeoff between sensor resolution and orbital return period may also play a role in the ability to detect catastrophic loss. Moderate resolution imagery (e.g. Moderate Resolution Imaging Spectroradiometer (MODIS)) provides relatively coarse surface detail with a higher update rate which could hinder the identification of small regions that underwent a dynamic change. Alternatively, imagery with higher spatial resolution (e.g. Landsat) have a longer temporal return period between successive images which could result in natural recovery underestimating the absolute magnitude of damage incurred. This study evaluates the role of land cover type and sensor resolution on four high-end (EF3+) tornado events occurring in four different land cover groups (agriculture, forest, grassland, urban) in the spring season. The closest successive clear images from both Landsat 5 and MODIS are quality controlled for each case. Transacts of surface reflectance across a homogenous land cover type both inside and outside the damage swath are extracted. These metrics are synthesized through the calculation of six different VIs to rank the calculated change metrics by land cover type, sensor resolution and VI.

Regional climate model assessment of the urban land-surface forcing over central Europe

NASA Astrophysics Data System (ADS)

Huszar, P.; Halenka, T.; Belda, M.; Zak, M.; Sindelarova, K.; Miksovsky, J.

2014-07-01

For the purpose of qualifying and quantifying the climate impact of cities and urban surfaces in general on climate of central Europe, the surface parameterization in regional climate model RegCM4 has been extended with the Single Layer Urban Canopy Model (SLUCM). A set of experiments was performed over the period of 2005-2009 for central Europe, either without considering urban surfaces or with the SLUCM treatment. Results show a statistically significant impact of urbanized surfaces on temperature (up to 1.5 K increase in summer) as well as on the boundary layer height (increases up to 50 m). Urbanization further influences surface wind with a winter decrease up to -0.6 m s-1, though both increases and decreases were detected in summer depending on the location relative to the cities and daytime (changes up to 0.3 m s-1). Urban surfaces significantly reduce evaporation and thus the humidity over the surface. This impacts the simulated summer precipitation rate, showing decrease over cities up to -2 mm day-1. Significant temperature increases are simulated over higher elevations as well, not only within the urban canopy layer. With the urban parameterization, the climate model better describes the diurnal temperature variation, reducing the cold afternoon and evening bias of RegCM4. Sensitivity experiments were carried out to quantify the response of the meteorological conditions to changes in the parameters specific to the urban environment such as street width, building height, albedo of the roofs and anthropogenic heat release. The results proved to be rather robust and the choice of the key SLUCM parameters impacts them only slightly (mainly temperature, boundary layer height and wind velocity). Statistically significant impacts are modeled not only over large urbanized areas, but the influence of the cities is also evident over rural areas without major urban surfaces. It is shown that this is the result of the combined effect of the distant influence of the cities and the influence of the minor local urban surface coverage.

Regional climate model assessment of the urban land-surface forcing over central Europe

NASA Astrophysics Data System (ADS)

Huszar, P.; Halenka, T.; Belda, M.; Zak, M.; Sindelarova, K.; Miksovsky, J.

2014-11-01

For the purpose of qualifying and quantifying the climate impact of cities and urban surfaces in general on climate of central Europe, the surface parameterization in regional climate model RegCM4 has been extended with the Single-layer Urban Canopy Model (SLUCM). A set of experiments was performed over the period of 2005-2009 for central Europe, either without considering urban surfaces or with the SLUCM treatment. Results show a statistically significant impact of urbanized surfaces on temperature (up to 1.5 K increase in summer) as well as on the boundary layer height (increases up to 50 m). Urbanization further influences surface wind with a winter decrease up to -0.6 m s-1, though both increases and decreases were detected in summer depending on the location relative to the cities and daytime (changes up to 0.3 m s-1). Urban surfaces significantly reduce the humidity over the surface. This impacts the simulated summer precipitation rate, showing a decrease over cities of up to -2 mm day-1. Significant temperature increases are simulated over higher altitudes as well, not only within the urban canopy layer. With the urban parameterization, the climate model better describes the diurnal temperature variation, reducing the cold afternoon and evening bias of RegCM4. Sensitivity experiments were carried out to quantify the response of the meteorological conditions to changes in the parameters specific to the urban environment, such as street width, building height, albedo of the roofs and anthropogenic heat release. The results proved to be rather robust and the choice of the key SLUCM parameters impacts them only slightly (mainly temperature, boundary layer height and wind velocity). Statistically significant impacts are modelled not only over large urbanized areas, but the influence of the cities is also evident over rural areas without major urban surfaces. It is shown that this is the result of the combined effect of the distant influence of the cities and the influence of the minor local urban surface coverage.

Removing non-urban roads from the National Land Cover Database to create improved urban maps for the United States, 1992-2011

USGS Publications Warehouse

Soulard, Christopher E.; Acevedo, William; Stehman, Stephen V.

2018-01-01

Quantifying change in urban land provides important information to create empirical models examining the effects of human land use. Maps of developed land from the National Land Cover Database (NLCD) of the conterminous United States include rural roads in the developed land class and therefore overestimate the amount of urban land. To better map the urban class and understand how urban lands change over time, we removed rural roads and small patches of rural development from the NLCD developed class and created four wall-to-wall maps (1992, 2001, 2006, and 2011) of urban land. Removing rural roads from the NLCD developed class involved a multi-step filtering process, data fusion using geospatial road and developed land data, and manual editing. Reference data classified as urban or not urban from a stratified random sample was used to assess the accuracy of the 2001 and 2006 urban and NLCD maps. The newly created urban maps had higher overall accuracy (98.7 percent) than the NLCD maps (96.2 percent). More importantly, the urban maps resulted in lower commission error of the urban class (23 percent versus 57 percent for the NLCD in 2006) with the trade-off of slightly inflated omission error (20 percent for the urban map, 16 percent for NLCD in 2006). The removal of approximately 230,000 km2 of rural roads from the NLCD developed class resulted in maps that better characterize the urban footprint. These urban maps are more suited to modeling applications and policy decisions that rely on quantitative and spatially explicit information regarding urban lands.

ERTS-1 Role in land management and planning in Minnesota

NASA Technical Reports Server (NTRS)

Sizer, J. E.; Brown, D. A.

1974-01-01

Research on applications of ERTS-1 imagery to land use has focused on evaluating the ability of ERTS-1 imagery to update and refine the detail of land use information in the Minnesota Land Management Information System. Work has been directed toward defining the capabilities of the ERTS-1 system to provide information about surface cover by identifying forest, water, and wetland resources; urban and agricultural development: and testing and evaluating data input and output procedures. As capabilities were developed, meetings were held with administrators and resource information users from various agencies of government to identify their information needs. A full scale systems test for several selected pilot areas in the state is nearly complete. Users have been identified for each test area and they have been instrumental in identifying data requirements and analysis needs for administrative purposes. Users have both rural and urban orientations and provide a basis for evaluation of the results.

Planning applications of remote sensing in Arizona

NASA Technical Reports Server (NTRS)

Clark, R. B.; Mouat, D. A.

1976-01-01

Planners in Arizona have been experiencing the inevitable problems which occur when large areas of rural and remote lands are converted to urban-recreational uses over a relatively short period of time. Among the planning problems in the state are unplanned and illegal subdivisions, surburban sprawl, surface hydrologic problems related to ephemeral stream overflow, rapidly changing land use patterns, large size of administrative units, and lack of land use inventory data upon which to base planning decisions.

Influences of different land use spatial control schemes on farmland conversion and urban development.

PubMed

Zhou, Min; Tan, Shukui; Zhang, Lu

2015-01-01

Land use planning is always officially implemented as an effective tool to control urban development and protect farmland. However, its impact on land use change remains untested in China. Using a case study of Hang-Jia-Hu region, the main objective of this paper was to investigate the influence of different land use spatial control schemes on farmland conversion and urban development. Comparisons of farmland conversion and urban development patterns between the urban planning area and the non-urban planning area were characterized by using remote sensing, geographical information systems, and landscape metrics. Results indicated that farmland conversion in the non-urban planning area was more intensive than that in the urban planning area, and that farmland patterns was more fragmented in the non-urban planning area. Built-up land patterns in the non-urban planning area showed a trend of aggregation, while those in the urban planning area had a dual trend of fragmentation and aggregation. Existing built-up areas had less influence on built-up land sprawl in the non-urban planning area than that in the urban planning area. Built-up land sprawl in the form of continuous development in the urban planning area led to farmland conversion; and in the non-urban planning area, built-up land sprawl in the form of leapfrogging development resulted in farmland areal declines and fragmentation. We argued that it is a basic requirement to integrate land use plans in urban and non-urban planning areas for land use planning and management.

Influences of Different Land Use Spatial Control Schemes on Farmland Conversion and Urban Development

PubMed Central

Zhou, Min; Tan, Shukui; Zhang, Lu

2015-01-01

Land use planning is always officially implemented as an effective tool to control urban development and protect farmland. However, its impact on land use change remains untested in China. Using a case study of Hang-Jia-Hu region, the main objective of this paper was to investigate the influence of different land use spatial control schemes on farmland conversion and urban development. Comparisons of farmland conversion and urban development patterns between the urban planning area and the non-urban planning area were characterized by using remote sensing, geographical information systems, and landscape metrics. Results indicated that farmland conversion in the non-urban planning area was more intensive than that in the urban planning area, and that farmland patterns was more fragmented in the non-urban planning area. Built-up land patterns in the non-urban planning area showed a trend of aggregation, while those in the urban planning area had a dual trend of fragmentation and aggregation. Existing built-up areas had less influence on built-up land sprawl in the non-urban planning area than that in the urban planning area. Built-up land sprawl in the form of continuous development in the urban planning area led to farmland conversion; and in the non-urban planning area, built-up land sprawl in the form of leapfrogging development resulted in farmland areal declines and fragmentation. We argued that it is a basic requirement to integrate land use plans in urban and non-urban planning areas for land use planning and management. PMID:25915897

A Study on the Assessment of Multi-Factors Affecting Urban Floods Using Satellite Image: A Case Study in Nakdong Basin, S. Korea

NASA Astrophysics Data System (ADS)

Kwak, Youngjoo; Kondoh, Akihiko

2010-05-01

Floods are also related to the changes in social economic conditions and land use. Recently, floods increased due to rapid urbanization and human activity in the lowland. Therefore, integrated management of total basin system is necessary to get the secure society. Typhoon ‘Rusa’ swept through eastern and southern parts of South Korea in the 2002. This pity experience gave us valuable knowledge that could be used to mitigate the future flood hazards. The purpose of this study is to construct the digital maps of the multi-factors related to urban flood concerning geomorphologic characteristics, land cover, and surface wetness. Parameters particularly consider geomorphologic functional unit, geomorphologic parameters derived from DEM (digital elevation model), and land use. The research area is Nakdong River Basin in S. Korea. As a result of preliminary analysis for Pusan area, the vulnerability map and the flood-prone areas can be extracted by applying spatial analysis on GIS (geographic information system).

Residential Exposure to Nighttime Retained Heat in the El Paso, Texas, USA Desert Metroplex

NASA Astrophysics Data System (ADS)

Amaya, M. A.; Mohammed, M.; Pingitore, N. E.; Aldouri, R. K.; Benedict, B. A.

2013-12-01

The urban heat island is a well recognized and extensively studied phenomenon that has accelerating importance resulting from two trends associated with world-wide population growth: increasing urbanization and global warming. Urbanization, particularly when unplanned and haphazard, changes such thermal parameters as albedo, surface roughness, and heat capacities of surface materials. Rapid urbanization in the contiguous El Paso, Texas, USA - Ciudad Juarez, Chihuahua, Mexico bi-national metroplex has produced an urban heat island that is warmer than the surrounding Chihuahuan desert (temperature: 35-40 C summer; high elevation: 600-1675 m; rainfall: less than 250 mm annual). Despite the extensive literature on the urban heat island, little is known about urban nighttime land surface temperatures. We employed infrared satellite imaging to establish the variation of nighttime neighborhood surface temperatures across the city of El Paso, as well as all of El Paso County. The underlying purpose of our continuing investigation is to evaluate the geography of morbidity risk: are different neighborhoods at different risk of high nighttime temperatures. Those risks can include heat stress, and irritability and sleep deprivation, with possible resultant violence. Heat exposure at night is significant because residents are at home and 90% of El Pasoans do not have 'refrigerated' air conditioning, but instead have evaporative coolers, which are less expensive to own and operate, but are less effective since they raise the humidity of the partially cooled air. Our geographically weighted regression model showed that both day and nighttime land surface temperatures correlated with the normalized difference vegetation index, population density, and albedo. The association with the index and albedo was stronger during the daytime and with population density during the nighttime. Vegetation (negative) and population density (positive) were the dominant temperature drivers, with albedo and elevation as secondary drivers. Using archived satellite imagery we determined that over the last two decades there has been an increase in both day and nighttime temperatures. With no expected change in urban growth and global warming, local residents will be at increasing risk in the future, as will residents in other urban centers in the desert southwest of the US. We currently are evaluating exposure risk in different population sectors. Do the aged or the poor reside in higher risk neighborhoods? Are there simple measures that can be taken to ameliorate nighttime temperatures?

Urban Soil: Assessing Ground Cover Impact on Surface Temperature and Thermal Comfort.

PubMed

Brandani, Giada; Napoli, Marco; Massetti, Luciano; Petralli, Martina; Orlandini, Simone

2016-01-01

The urban population growth, together with the contemporary deindustrialization of metropolitan areas, has resulted in a large amount of available land with new possible uses. It is well known that urban green areas provide several benefits in the surrounding environment, such as the improvement of thermal comfort conditions for the population during summer heat waves. The purpose of this study is to provide useful information on thermal regimes of urban soils to urban planners to be used during an urban transformation to mitigate surface temperatures and improve human thermal comfort. Field measurements of solar radiation, surface temperature (), air temperature (), relative humidity, and wind speed were collected on four types of urban soils and pavements in the city of Florence during summer 2014. Analysis of days under calm, clear-sky condition is reported. During daytime, sun-to-shadow differences for , apparent temperature index (ATI), and were significantly positive for all surfaces. Conversely, during nighttime, differences among all surfaces were significantly negative, whereas ATI showed significantly positive differences. Moreover, was significantly negative for grass and gravel. Relative to the shaded surfaces, was higher on white gravel and grass than gray sandstone and asphalt during nighttime, whereas gray sandstone was always the warmest surface during daytime. Conversely, no differences were found during nighttime for ATI and measured over surfaces that were exposed to sun during the day, whereas showed higher values on gravel than grass and asphalt during nighttime. An exposed surface warms less if its albedo is high, leading to a significant reduction of during daytime. These results underline the importance of considering the effects of surface characteristics on surface temperature and thermal comfort. This would be fundamental for addressing urban environment issues toward the heat island mitigation considering also the impact of urban renovation on microclimate. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The contribution of urbanization to recent extreme heat events and a potential mitigation strategy in the Beijing-Tianjin-Hebei metropolitan area

NASA Astrophysics Data System (ADS)

Wang, Mingna; Yan, Xiaodong; Liu, Jiyuan; Zhang, Xuezhen

2013-11-01

This paper addresses the contribution of urban land use change to near-surface air temperature during the summer extreme heat events of the early twenty-first century in the Beijing-Tianjin-Hebei metropolitan area. This study uses the Weather Research Forecasting model with a single urban canopy model and the newest actual urban cover datasets. The results show that urban land use characteristics that have evolved over the past ~20 years in the Beijing-Tianjin-Hebei metropolitan area have had a significant impact on the extreme temperatures occurring during extreme heat events. Simulations show that new urban development has caused an intensification and expansion of the areas experiencing extreme heat waves with an average increase in temperature of approximately 0.60 °C. This change is most obvious at night with an increase up to 0.95 °C, for which the total contribution of anthropogenic heat is 34 %. We also simulate the effects of geo-engineering strategies increasing the albedo of urban roofs, an effective way of reducing urban heat island, which can reduce the urban mean temperature by approximately 0.51 °C and counter approximately 80 % of the heat wave results from urban sprawl during the last 20 years.

The Urban Environmental Monitoring/100 Cities Project: Legacy of the First Phase and Next Steps

NASA Technical Reports Server (NTRS)

Stefanov, William L.; Wentz, Elizabeth A.; Brazel, Anthony; Netzband, Maik; Moeller, Matthias

2009-01-01

The Urban Environmental Monitoring (UEM) project, now known as the 100 Cities Project, at Arizona State University (ASU) is a baseline effort to collect and analyze remotely sensed data for 100 urban centers worldwide. Our overarching goal is to use remote sensing technology to better understand the consequences of rapid urbanization through advanced biophysical measurements, classification methods, and modeling, which can then be used to inform public policy and planning. Urbanization represents one of the most significant alterations that humankind has made to the surface of the earth. In the early 20th century, there were less than 20 cities in the world with populations exceeding 1 million; today, there are more than 400. The consequences of urbanization include the transformation of land surfaces from undisturbed natural environments to land that supports different forms of human activity, including agriculture, residential, commercial, industrial, and infrastructure such as roads and other types of transportation. Each of these land transformations has impacted, to varying degrees, the local climatology, hydrology, geology, and biota that predate human settlement. It is essential that we document, to the best of our ability, the nature of land transformations and the consequences to the existing environment. The focus in the UEM project since its inception has been on rapid urbanization. Rapid urbanization is occurring in hundreds of cities worldwide as population increases and people migrate from rural communities to urban centers in search of employment and a better quality of life. The unintended consequences of rapid urbanization have the potential to cause serious harm to the environment, to human life, and to the resulting built environment because rapid development constrains and rushes decision making. Such rapid decision making can result in poor planning, ineffective policies, and decisions that harm the environment and the quality of human life. Slower, more thought-out, decision making could result in more favorable outcomes. The harm to the environment includes poor air quality, soil erosion, polluted rivers and aquifers, and loss of wildlife habitat. Human life is then threatened because of increased potential for disease spreading, human conflict, environmental hazards, and diminished quality of life. The built environment is potentially threatened when cities are built in areas that can be impacted by events such as hurricanes, tsunamis, earthquakes, fires, and landslides. Our goals include assessing the threat of such events on cities and the people living there.

Evaluation of urban surface parameterizations in the WRF model using measurements during the Texas Air Quality Study 2006 field campaign

NASA Astrophysics Data System (ADS)

Lee, S.-H.; Kim, S.-W.; Angevine, W. M.; Bianco, L.; McKeen, S. A.; Senff, C. J.; Trainer, M.; Tucker, S. C.; Zamora, R. J.

2011-03-01

The performance of different urban surface parameterizations in the WRF (Weather Research and Forecasting) in simulating urban boundary layer (UBL) was investigated using extensive measurements during the Texas Air Quality Study 2006 field campaign. The extensive field measurements collected on surface (meteorological, wind profiler, energy balance flux) sites, a research aircraft, and a research vessel characterized 3-dimensional atmospheric boundary layer structures over the Houston-Galveston Bay area, providing a unique opportunity for the evaluation of the physical parameterizations. The model simulations were performed over the Houston metropolitan area for a summertime period (12-17 August) using a bulk urban parameterization in the Noah land surface model (original LSM), a modified LSM, and a single-layer urban canopy model (UCM). The UCM simulation compared quite well with the observations over the Houston urban areas, reducing the systematic model biases in the original LSM simulation by 1-2 °C in near-surface air temperature and by 200-400 m in UBL height, on average. A more realistic turbulent (sensible and latent heat) energy partitioning contributed to the improvements in the UCM simulation. The original LSM significantly overestimated the sensible heat flux (~200 W m-2) over the urban areas, resulting in warmer and higher UBL. The modified LSM slightly reduced warm and high biases in near-surface air temperature (0.5-1 °C) and UBL height (~100 m) as a result of the effects of urban vegetation. The relatively strong thermal contrast between the Houston area and the water bodies (Galveston Bay and the Gulf of Mexico) in the LSM simulations enhanced the sea/bay breezes, but the model performance in predicting local wind fields was similar among the simulations in terms of statistical evaluations. These results suggest that a proper surface representation (e.g. urban vegetation, surface morphology) and explicit parameterizations of urban physical processes are required for accurate urban atmospheric numerical modeling.

Impact of land cover change on the environmental hydrology characteristics in Kelantan river basin, Malaysia

NASA Astrophysics Data System (ADS)

Saadatkhah, Nader; Mansor, Shattri; Khuzaimah, Zailani; Asmat, Arnis; Adnan, Noraizam; Adam, Siti Noradzah

2016-09-01

Changing the land cover/ land use has serious environmental impacts affecting the ecosystem in Malaysia. The impact of land cover changes on the environmental functions such as surface water, loss water, and soil moisture is considered in this paper on the Kelantan river basin. The study area at the east coast of the peninsular Malaysia has suffered significant land cover changes in the recent years. The current research tried to assess the impact of land cover changes in the study area focused on the surface water, loss water, and soil moisture from different land use classes and the potential impact of land cover changes on the ecosystem of Kelantan river basin. To simulate the impact of land cover changes on the environmental hydrology characteristics, a deterministic regional modeling were employed in this study based on five approaches, i.e. (1) Land cover classification based on Landsat images; (2) assessment of land cover changes during last three decades; (3) Calculation the rate of water Loss/ Infiltration; (4) Assessment of hydrological and mechanical effects of the land cover changes on the surface water; and (5) evaluation the impact of land cover changes on the ecosystem of the study area. Assessment of land cover impact on the environmental hydrology was computed with the improved transient rainfall infiltration and grid based regional model (Improved-TRIGRS) based on the transient infiltration, and subsequently changes in the surface water, due to precipitation events. The results showed the direct increased in surface water from development area, agricultural area, and grassland regions compared with surface water from other land covered areas in the study area. The urban areas or lower planting density areas tend to increase for surface water during the monsoon seasons, whereas the inter flow from forested and secondary jungle areas contributes to the normal surface water.

Housing land transaction data and structural econometric estimation of preference parameters for urban economic simulation models

PubMed Central

Caruso, Geoffrey; Cavailhès, Jean; Peeters, Dominique; Thomas, Isabelle; Frankhauser, Pierre; Vuidel, Gilles

2015-01-01

This paper describes a dataset of 6284 land transactions prices and plot surfaces in 3 medium-sized cities in France (Besançon, Dijon and Brest). The dataset includes road accessibility as obtained from a minimization algorithm, and the amount of green space available to households in the neighborhood of the transactions, as evaluated from a land cover dataset. Further to the data presentation, the paper describes how these variables can be used to estimate the non-observable parameters of a residential choice function explicitly derived from a microeconomic model. The estimates are used by Caruso et al. (2015) to run a calibrated microeconomic urban growth simulation model where households are assumed to trade-off accessibility and local green space amenities. PMID:26958606

Understanding the health impacts of urbanization in China: A living laboratory for urban biogeochemistry research

NASA Astrophysics Data System (ADS)

Zhu, Y. G.

2015-12-01

China has the largest population in the world, and by 2011, more than 50% of its population are now living in cities. This ongoing societal change has profound impacts on environmental quality and population health. In addition to intensive discharges of waste, urbanization is not only changing the land use and land cover, but also inducing fundamental changes in biogeochemical processes. Unlike biogeochemistry in non-urban environment, the biological component of urban biogeochemistry is dominated by direct human activities, such as air pollution derived from transport, wastewater treatment, garbage disposal and increase in impervious surface etc. Managing urban biogeochemistry will include source control over waste discharge, eco-infrastructure (such as green space and eco-drainage), resource recovery from urban waste stream, and integration with peri-urban ecosystem, particularly with food production system. The overall goal of managing urban biogeochemistry is for human health and wellbeing, which is a global challenge. In this paper, the current status of urban biogeochemistry research in China will be briefly reviewed, and then it will focus on nutrient recycling and waste management, as these are the major driving forces of environmental quality changes in urban areas. This paper will take a holistic view on waste management, covering urban metabolism analysis, technological innovation and integration for resource recovery from urban waste stream, and risk management related to waste recycling and recovery.

Urban land teleconnections and sustainability

PubMed Central

Seto, Karen C.; Reenberg, Anette; Boone, Christopher G.; Fragkias, Michail; Haase, Dagmar; Langanke, Tobias; Marcotullio, Peter; Munroe, Darla K.; Olah, Branislav; Simon, David

2012-01-01

This paper introduces urban land teleconnections as a conceptual framework that explicitly links land changes to underlying urbanization dynamics. We illustrate how three key themes that are currently addressed separately in the urban sustainability and land change literatures can lead to incorrect conclusions and misleading results when they are not examined jointly: the traditional system of land classification that is based on discrete categories and reinforces the false idea of a rural–urban dichotomy; the spatial quantification of land change that is based on place-based relationships, ignoring the connections between distant places, especially between urban functions and rural land uses; and the implicit assumptions about path dependency and sequential land changes that underlie current conceptualizations of land transitions. We then examine several environmental “grand challenges” and discuss how urban land teleconnections could help research communities frame scientific inquiries. Finally, we point to existing analytical approaches that can be used to advance development and application of the concept. PMID:22550174

Comparison of WRF local and nonlocal boundary layer Physics in Greater Kuala Lumpur, Malaysia

NASA Astrophysics Data System (ADS)

Ooi, M. C. G.; Chan, A.; Kumarenthiran, S.; Morris, K. I.; Oozeer, M. Y.; Islam, M. A.; Salleh, S. A.

2018-02-01

The urban boundary layer (UBL) is the internal advection layer of atmosphere above urban region which determines the exchanges of momentum, water and other atmospheric constituents between the urban land surface and the free troposphere. This paper tested the performance of three planetary boundary layer (PBL) physics schemes of Weather Research and Forecast (WRF) software to ensure the appropriate representation of vertical structure of UBL in Greater Kuala Lumpur (GKL). Comparison was conducted on the performance of respective PBL schemes to generate vertical and near-surface weather profile and rainfall. Mellor-Yamada- Janjíc (MYJ) local PBL scheme coupled with Eta MM5 surface layer scheme was found to predict the near-surface temperature and wind profile and mixing height better than the nonlocal schemes during the intermonsoonal period with least influences of the synoptic background weather.

Correlation between land cover and ground vulnerability in Alexandria City (Egypt) using time series SAR interferometry and optical Earth observation data

NASA Astrophysics Data System (ADS)

Seleem, T.; Stergiopoulos, V.; Kourkouli, P.; Perrou, T.; Parcharidis, Is.

2017-10-01

The main scope of this study is to investigate the potential correlation between land cover and ground vulnerability over Alexandria city, Egypt. Two different datasets for generating ground deformation and land cover maps were used. Hence, two different approaches were followed, a PSI approach for surface displacement mapping and a supervised classification algorithm for land cover/use mapping. The interferometric results show a gradual qualitative and quantitative differentiation of ground deformation from East to West of Alexandria government. We selected three regions of interest, in order to compare the obtained interferometric results with the different land cover types. The ground deformation may be resulted due to different geomorphic and geologic factors encompassing the proximity to the active deltaic plain of the Nile River, the expansion of the urban network within arid regions of recent deposits, the urban density increase, and finally the combination of the above mentioned parameters.

Reconstructed historical land cover and biophysical parameters for studies of land-atmosphere interactions within the eastern United States

USGS Publications Warehouse

Steyaert, Louis T.; Knox, R.G.

2008-01-01

Over the past 350 years, the eastern half of the United States experienced extensive land cover changes. These began with land clearing in the 1600s, continued with widespread deforestation, wetland drainage, and intensive land use by 1920, and then evolved to the present-day landscape of forest regrowth, intensive agriculture, urban expansion, and landscape fragmentation. Such changes alter biophysical properties that are key determinants of land-atmosphere interactions (water, energy, and carbon exchanges). To understand the potential implications of these land use transformations, we developed and analyzed 20-km land cover and biophysical parameter data sets for the eastern United States at 1650, 1850, 1920, and 1992 time slices. Our approach combined potential vegetation, county-level census data, soils data, resource statistics, a Landsat-derived land cover classification, and published historical information on land cover and land use. We reconstructed land use intensity maps for each time slice and characterized the land cover condition. We combined these land use data with a mutually consistent set of biophysical parameter classes, to characterize the historical diversity and distribution of land surface properties. Time series maps of land surface albedo, leaf area index, a deciduousness index, canopy height, surface roughness, and potential saturated soils in 1650, 1850, 1920, and 1992 illustrate the profound effects of land use change on biophysical properties of the land surface. Although much of the eastern forest has returned, the average biophysical parameters for recent landscapes remain markedly different from those of earlier periods. Understanding the consequences of these historical changes will require land-atmosphere interactions modeling experiments.

Habitat complexity influences fine scale hydrological processes and the incidence of stormwater runoff in managed urban ecosystems.

PubMed

Ossola, Alessandro; Hahs, Amy Kristin; Livesley, Stephen John

2015-08-15

Urban ecosystems have traditionally been considered to be pervious features of our cities. Their hydrological properties have largely been investigated at the landscape scale and in comparison with other urban land use types. However, hydrological properties can vary at smaller scales depending upon changes in soil, surface litter and vegetation components. Management practices can directly and indirectly affect each of these components and the overall habitat complexity, ultimately affecting hydrological processes. This study aims to investigate the influence that habitat components and habitat complexity have upon key hydrological processes and the implications for urban habitat management. Using a network of urban parks and remnant nature reserves in Melbourne, Australia, replicate plots representing three types of habitat complexity were established: low-complexity parks, high-complexity parks, and high-complexity remnants. Saturated soil hydraulic conductivity in low-complexity parks was an order of magnitude lower than that measured in the more complex habitat types, due to fewer soil macropores. Conversely, soil water holding capacity in low-complexity parks was significantly higher compared to the two more complex habitat types. Low-complexity parks would generate runoff during modest precipitation events, whereas high-complexity parks and remnants would be able to absorb the vast majority of rainfall events without generating runoff. Litter layers on the soil surface would absorb most of precipitation events in high-complexity parks and high-complexity remnants. To minimize the incidence of stormwater runoff from urban ecosystems, land managers could incrementally increase the complexity of habitat patches, by increasing canopy density and volume, preserving surface litter and maintaining soil macropore structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Geospatial Strategy for Adverse Impact of Urban Heat Island in upper atmospheres of the earth Mountain Areas using LANDSAT ETM+ Sensors

NASA Astrophysics Data System (ADS)

Kumar, Amit; Vandana, Vandana

2016-07-01

We are living in the age of the rapidly growing population and changing environmental conditions with advanced technical capacity. This has been resulting in widespread land cover change. Among several human-induced environmental and urban thermal problems are reported to be negatively affecting urban residents in many ways. Urban Heat Islands exist in many large cities especially metropolitan cities and can significantly affect the permafrost layer in mountain areas. The adverse effect of urban heat island has become the subject of numerous studies in recent decades and is reflected in many major mountain cities around the world. The built-up structures in urbanized areas considerably alter land cover thereby affecting thermal energy flow which leads to the development of elevated surface and air temperature. The phenomenon Urban Heat Island implies 'island' of high temperature in cities, surrounded by relatively lower temperature in rural areas. The Urban Heat Island for the temporal period is estimated using geospatial techniques which are then utilized for the impact assessment of the climate of the surrounding regions and how it reduce the sustainability of the natural resources like air, vegetation. The knowledge of surface temperature is important for the study of urban climate and human health. The rapid growth of industries in peri-urban areas results in excessive warming and variations in weather conditions. It leads to soil degradation in frozen areas due to high temperature which leads to melting of snow in mountain areas Remotely sensed data of thermal infrared band in the region of 10.4-12.5 µm of EMR spectrum, available from LANDSAT- ETM+ is proved to be very helpful to identify urban heat islands. Thermal infrared data acquired during the daytime and night time can be used to monitor the heat island associated with urban areas as well as atmospheric pollution. The present paper describes the methodology and resolution dynamic urban heat island change on climate and soil using geospatial approach for Haridwar district of Uttrakhand. NDVI were generated using daytime LANDSAT ETM+ image of November 1990, 2000 and 2015. The temperature of various land use and land cover categories was estimated. In Haridwar district, the temperature is inversely related and negatively correlated with NDVI value. The paper considers this dimension and calculated UHI at multiple scales through surface conditions such as vegetation. The major part of the field were conceded out in moderate summer conditions due to rainfall, yet the heat island intensities obtained in the study were comparable to those observed in earlier studies. Moreover, very high UHI was observed in the later phase of the experiments when usual summer conditions were restored. Also, the present study has showed that heat island effect need not be limited to a particular temperature epoch which signals towards the increasing dominance of anthropogenic heat emissions in rapidly developing cities such as Haridwar District in Uttrakhand, India. The use of the technological resources should be such that it does not affect the sustainability of natural resources. For compensation of the adverse effect of UHI, the urban built up cover should be reduced to an extent but in real, it is not possible due to the proclivity of the human towards urbanization. A thick subsurface layer of soil that remains below freezing point throughout the year, occurring chiefly in polar regions.

Analysis and Application of Airborne Thermal Data at the Local Level Salt Lake City, Utah

NASA Technical Reports Server (NTRS)

Dudley-Murphy, Elizabeth A.

1999-01-01

Expanding cities are transforming periurban environments such as agricultural land, natural grasslands, forests, wetlands, and and land, into urban surfaces, such as asphalt and concrete. This transformation is part of a process defined as "urban heat island". The urban surfaces get much hotter during the daylight hours in the summer than the natural or vegetated environment. The heat builds up creating a dome effect over the city making it many degrees hotter than it's surrounding area. The impacts from this, which include higher usage of air conditioners, water, etc., are numerous and costly. As cities expand, this problem is exacerbated. It is necessary to incorporate better quality data into urban analysis and for establishing methods that systematically and objectively monitor growth and change due to increased urbanization. NASA initiated Project Atlanta in 1997 "as an interdisciplinary remote sensing study to observe and measure the growth and development of the urban heat island effect over Atlanta, and its associated impacts". This project has recently included Salt Lake City, among others, in the study of the development and effects of "urban heat islands". NASA has made available to Salt Lake City, high resolution, 10 meter, multispectral thermal data collected in June 1998. The data collection was part of a special NASA over-flight, a mission supported by the U.S. EPA in conjunction with their Urban Heat Island (UHI) Mitigation Initiative. Salt Lake City is one of three pilot cities selected to participate in this unique initiative. Hence, this project constitutes a rare opportunity to capitalize upon state-of-the-art NASA technology and link it to an urban community very concerned about rapid growth and development. This data will enhance existing data and be used for improving technical tools used to plan for Utah's future.

Beyond imperviousness: A statistical approach to identifying functional differences between development morphologies on variable source area-type response in urbanized watersheds

NASA Astrophysics Data System (ADS)

Lim, T. C.

2016-12-01

Empirical evidence has shown linkages between urbanization, hydrological regime change, and degradation of water quality and aquatic habitat. Percent imperviousness, has long been suggested as the dominant source of these negative changes. However, recent research identifying alternative pathways of runoff production at the watershed scale have called into question percent impervious surface area's primacy in urban runoff production compared to other aspects of urbanization including change in vegetative cover, imported water and water leakages, and the presence of drainage infrastructure. In this research I show how a robust statistical methodology can detect evidence of variable source area (VSA)-type hydrologic response associated with incremental hydraulic connectivity in watersheds. I then use logistic regression to explore how evidence of VSA-type response relates to the physical and meterological characteristics of the watershed. I find that impervious surface area is highly correlated with development, but does not add significant explanatory power beyond percent developed in predicting VSA-type response. Other aspects of development morphology, including percent developed open space and type of drainage infrastructure also do not add to the explanatory power of undeveloped land in predicting VSA-type response. Within only developed areas, the effect of developed open space was found to be more similar to that of total impervious area than to undeveloped land. These findings were consistent when tested across a national cross-section of urbanized watersheds, a higher resolution dataset of Baltimore Metropolitan Area watersheds, and a subsample of watersheds confirmed not to be served by combined sewer systems. These findings suggest that land development policies that focus on lot coverage should be revisited, and more focus should be placed on preserving native vegetation and soil conditions alongside development.

Land use and land cover changes in Zêzere watershed (Portugal)--Water quality implications.

PubMed

Meneses, B M; Reis, R; Vale, M J; Saraiva, R

2015-09-15

To understand the relations between land use allocation and water quality preservation within a watershed is essential to assure sustainable development. The land use and land cover (LUC) within Zêzere River watershed registered relevant changes in the last decades. These land use and land cover changes (LUCCs) have impacts in water quality, mainly in surface water degradation caused by surface runoff from artificial and agricultural areas, forest fires and burnt areas, and caused by sewage discharges from agroindustry and urban sprawl. In this context, the impact of LUCCs in the quality of surface water of the Zêzere watershed is evaluated, considering the changes for different types of LUC and establishing their possible correlations to the most relevant water quality changes. The results indicate that the loss of coniferous forest and the increase of transitional woodland-shrub are related to increased water's pH; while the growth in artificial surfaces and pastures leads mainly to the increase of soluble salts and fecal coliform concentration. These particular findings within the Zêzere watershed, show the relevance of addressing water quality impact driven from land use and should therefore be taken into account within the planning process in order to prevent water stress, namely within watersheds integrating drinking water catchments. Copyright © 2015 Elsevier B.V. All rights reserved.

A Hierarchical Object-oriented Urban Land Cover Classification Using WorldView-2 Imagery and Airborne LiDAR data

NASA Astrophysics Data System (ADS)

Wu, M. F.; Sun, Z. C.; Yang, B.; Yu, S. S.

2016-11-01

In order to reduce the “salt and pepper” in pixel-based urban land cover classification and expand the application of fusion of multi-source data in the field of urban remote sensing, WorldView-2 imagery and airborne Light Detection and Ranging (LiDAR) data were used to improve the classification of urban land cover. An approach of object- oriented hierarchical classification was proposed in our study. The processing of proposed method consisted of two hierarchies. (1) In the first hierarchy, LiDAR Normalized Digital Surface Model (nDSM) image was segmented to objects. The NDVI, Costal Blue and nDSM thresholds were set for extracting building objects. (2) In the second hierarchy, after removing building objects, WorldView-2 fused imagery was obtained by Haze-ratio-based (HR) fusion, and was segmented. A SVM classifier was applied to generate road/parking lot, vegetation and bare soil objects. (3) Trees and grasslands were split based on an nDSM threshold (2.4 meter). The results showed that compared with pixel-based and non-hierarchical object-oriented approach, proposed method provided a better performance of urban land cover classification, the overall accuracy (OA) and overall kappa (OK) improved up to 92.75% and 0.90. Furthermore, proposed method reduced “salt and pepper” in pixel-based classification, improved the extraction accuracy of buildings based on LiDAR nDSM image segmentation, and reduced the confusion between trees and grasslands through setting nDSM threshold.

Catchment hydrological change from soil degradation: A model study for assessing urbanization on the terrestrial water cycle

NASA Astrophysics Data System (ADS)

Shu, L.; Duffy, C.

2015-12-01

It is commonly held that land cover and land use changes from agriculture and urbanization impact the terrestrial water cycle primarily through changes in the land surface and canopy energy balance. Another, and in some cases more important factor is the role that landuse changes have on soil structure, compaction, and loss of carbon on hydrologic performance. The consequential change on soil properties, such as aggregation of soil particles, reduction of voids, impacts on matrix conductivity and macropore fractions, alter the hydrological processes in a watershed. Macropores promote rapid water and gas movement under wet conditions while the soil matrix preserves the water-holding capacity necessary for plant growth. The physically-based Penn State Integrated Hydrologic Model (PIHM) simulates water movement in soil with Richard's equation using an effective matrix-macropore conductivity. The model is able to capture the preferential flow and soil water storage in vertical and horizontal directions. Soil degradation leads to a reduction of the macropore fraction with dramatic changes in overall hydrologic performance under urban development and agricultural landuse practices. The effects on the terrestrial water cycle in the catchment reduce infiltration, soil water availability, recharge and subsurface baseflow to streams, while increasing heavy surface runoff and erosion. The Lancaster area and surrounding watershed in eastern Pennsylvania, USA is a benchmark watershed comprised of urban (24%), agricultural (58%) and forest lands (18%) respectively. After parameter estimation from national geospatial soils, landuse and historical climate reanalysis, three landuse scenarios were developed. 1) Pre-development forest landuse (<1700 AD), (2) deforestation for agriculture and light urban landuse (1700-1900), (3) urban-suburban development (1900-pres.). The watershed model was used to evaluate hydrologic changes due to landuse change and soil degradation. The effects of macropore reduction and compaction on hydrologic performance were found to be of the same order or greater magnitude than for changes in landuse practices alone. The research, funded by the US EPA, illustrates the complex interaction of landuse and soil changes on the terrestrial water cycle.

Land use change and effects on water quality and ecosystem health in the Lake Tahoe basin, Nevada and California

USGS Publications Warehouse

Forney, William; Richards, Lora; Adams, Kenneth D.; Minor, Timothy B.; Rowe, Timothy G.; Smith, J. LaRue; Raumann, Christian G.

2001-01-01

Human activity in the Lake Tahoe Basin has increased substantially in the past four decades, causing significant impacts on the quality and clarity of the lake's famous deep, clear water. Protection of Lake Tahoe and the surrounding environment has become an important activity in recent years. A variety of agencies, including the Tahoe Regional Planning Agency, Tahoe Research Group of the University of California at Davis, Desert Research Institute of the University and Community College System of Nevada, U.S. Geological Survey (USGS), and a host of State (both Nevada and California) and local agencies have been monitoring and conducting research in the Basin in order to understand how the lake functions and to what extent humans have affected its landscape and ecosystem processes. In spite of all of these activities, there remains a lack of comprehensive land use change data and analysis for the Basin. A project is underway that unites the land cover mapping expertise of the USGS National Mapping Discipline with the hydrologic expertise of the Water Resources Discipline to assess the impacts of urban growth and land use change in the Lake Tahoe Basin. Three activities are planned over the next 3 years: (1) mapping the current and historic state of the land surface, (2) conducting analysis to document patterns, rates, and trends in urbanization, land use change, and ecosystem health, and (3) assessing the causes and consequences of land use change with regard to water quality and ecosystem health. We hypothesize that changes in the extent of urban growth and the corresponding increases in impervious surfaces and decreases in natural vegetation have resulted in severe impacts on ecosystem health and integrity, riparian zones and water quality over time. We are acting on multiple fronts to test this hypothesis through the quantification of landscape disturbances and impacts.

Impacts of land cover transitions on surface temperature in China based on satellite observations

NASA Astrophysics Data System (ADS)

Zhang, Yuzhen; Liang, Shunlin

2018-02-01

China has experienced intense land use and land cover changes during the past several decades, which have exerted significant influences on climate change. Previous studies exploring related climatic effects have focused mainly on one or two specific land use changes, or have considered all land use and land cover change types together without distinguishing their individual impacts, and few have examined the physical processes of the mechanism through which land use changes affect surface temperature. However, in this study, we considered satellite-derived data of multiple land cover changes and transitions in China. The objective was to obtain observational evidence of the climatic effects of land cover transitions in China by exploring how they affect surface temperature and to what degree they influence it through the modification of biophysical processes, with an emphasis on changes in surface albedo and evapotranspiration (ET). To achieve this goal, we quantified the changes in albedo, ET, and surface temperature in the transition areas, examined their correlations with temperature change, and calculated the contributions of different land use transitions to surface temperature change via changes in albedo and ET. Results suggested that land cover transitions from cropland to urban land increased land surface temperature (LST) during both daytime and nighttime by 0.18 and 0.01 K, respectively. Conversely, the transition of forest to cropland tended to decrease surface temperature by 0.53 K during the day and by 0.07 K at night, mainly through changes in surface albedo. Decreases in both daytime and nighttime LST were observed over regions of grassland to forest transition, corresponding to average values of 0.44 and 0.20 K, respectively, predominantly controlled by changes in ET. These results highlight the necessity to consider the individual climatic effects of different land cover transitions or conversions in climate research studies. This short-term analysis of land cover transitions in China means our estimates should represent local temperature effects. Changes in ET and albedo explained <60% of the variation in LST change caused by land cover transitions; thus, additional factors that affect surface climate need consideration in future studies.

Developing 3D morphologies for simulating building energy demand in urban microclimates

DOE Office of Scientific and Technical Information (OSTI.GOV)

New, Joshua Ryan; Omitaomu, Olufemi A.; Allen, Melissa R.

In order to simulate the effect of interactions between urban morphology and microclimate on demand for heating and cooling in buildings, we utilize source elevation data to create 3D building geometries at the neighborhood and city scale. Additionally, we use urban morphology concepts to design virtual morphologies for simulation scenarios in an undeveloped land parcel. Using these morphologies, we compute building-energy parameters such as the density for each surface and the frontal area index for each of the buildings to be able to effectively model the microclimate for the urban area.

Responses of benthic macroinvertebrates to urbanization in nine metropolitan areas of the conterminous United States

USGS Publications Warehouse

Cuffney, T.F.; McMahon, G.; Kashuba, R.; May, J.T.; Waite, I.R.

2009-01-01

The effects of urbanization on benthic macroinvertebrates were investigated in nine metropolitan areas (Boston, MA; Raleigh, NC; Atlanta, GA; Birmingham, AL; Milwaukee–Green Bay, WI; Denver, CO; Dallas–Fort Worth, TX; Salt Lake City, UT; and Portland, OR) as a part of the U.S. Geological Survey National Water Quality Assessment Program. Several invertebrate metrics showed strong, linear responses to urbanization when forest or shrublands were developed. Responses were difficult to discern in areas where urbanization was occurring on agricultural lands because invertebrate assemblages were already severely degraded. There was no evidence that assemblages showed any initial resistance to urbanization. Ordination scores, EPT taxa richness, and the average tolerance of organisms were the best indicators of changes in assemblage condition at a site. Richness metrics were better indicators than abundance metrics, and qualitative samples were as good as quantitative samples. A common set of landscape variables (population density, housing density, developed landcover, impervious surface, and roads) were strongly correlated with urbanization and invertebrate responses in all non-agricultural areas. The instream environmental variables (hydrology, water chemistry, habitat, and temperature) that were strongly correlated with urbanization and invertebrate responses were influenced by environmental setting (e.g., dominant ecoregion) and varied widely among metropolitan areas. Multilevel hierarchical regression models were developed that predicted invertebrate responses using only two landcover variables—basinscale landcover (percentage of basin area in developed land) and regional-scale landcover (antecedent agricultural land).

Final Environmental Assessment for National Air & Space Intelligence Center and US Air Force School of Aerospace Medicine Field Training Activities at Wright-Patterson Air Force Base, Ohio

DTIC Science & Technology

2011-04-14

characteristics in many locations and consequently most of the base has been mapped as disturbed urban land complexes. Major soil complexes represented...at WPAFB include: Warsaw-Fill land complex, Sloan-Fill land complex, Miamian- Urban land complex, Fox- Urban land complex, Linwood Muck, Westland- Urban ...land complex, and Warsaw- Urban land complex. 3.6.1 Proposed Action The project area for the alternative includes approximately 3.7 acres of property

Study of Spatial Variability of Air Temperature by Means of Remote Sensing Data and Weather Stations in Urban Areas: A Case Study for Campinas - São Paulo, Brazil.

NASA Astrophysics Data System (ADS)

Bezerra, L. M.; Avila, A. M. H. D.; Pereira, V. R.; Gonçalves, R. R. D. V.; Coltri, P. P.

2016-12-01

The surface meteorological and satellite Landsat8 data time series the city of Campinas, southeastern Brazil, has shown the rising temperatures in recent decades. According to scientific studies, part of this increase may be related to the urban sprawl of the city that currently has degree urbanization 98.28% and 1,164,098 inhabitants. Thus, the thermal images can represent reliable information of the surface temperature and this varies according to the land use and land cover. Therefore, were used 17 images of TIRS sensor (Thermal Infrared Sensor), band 10 and spatial resolution of 100 meters aboard satellite Landsat8 between 2013 and 2015 and temperature data from three meteorological stations of the city in different locations. After, was used the Pearson correlation between the measured weather data under 1.5 meters above ground level and surface temperature data estimated by satellite with a real difference 1 hour to less between stations and the satellite. The results indicated the 49% correlation in University of Campinas / Cepagri station, 86% in the Agronomic Institute of Campinas station and 90% in the Viracopos International Airport. This fact can be explained by the different degrees of urbanization where the weather stations are located and the heterogeneous characteristics of the local surface, as its roughness, impermeability, vegetation cover and concentration of buildings. Although these factors contribute to that there is a distortion of the surface temperature values detected by the satellite, the satellite was Landsat8 efficient to represent the spatial variability of temperature. In future studies, new techniques to obtain more accurate data through remote sensing will be studied.

Land cover impacts on stream nutrients and fecal coliform in the lower Piedmont of West Georgia

NASA Astrophysics Data System (ADS)

Schoonover, Jon E.; Lockaby, B. Graeme

2006-12-01

SummaryAs urbanization infiltrates into rural areas, stream water quality is expected to decline as a result from increased impervious surface and greater sources for pollutants. Consequently, West Georgia's water quality is threatened by extensive development as well as other land uses such as livestock grazing and silvicultural activity. Maintenance of stream water quality, as land development occurs, is critical for the protection of drinking water and biotic integrity. A 2-phase, watershed-scale study was established to develop relationships among land cover and water quality within western Georgia. During phase 1, nutrient and fecal coliform data were collected within 18 mixed land use watersheds, ranging in size from 500 to 2500 ha. Regression models were developed that related land cover to stream water nutrient and fecal coliform concentrations. Nutrient and fecal coliform concentrations within watersheds having >24% impervious surface (IS) were often higher than those in nonurban watersheds (i.e., <5% IS) during both base flow (N: 1.64 mg/L versus 0.61 mg/L, and FC: 430 versus 120 MPN/100 ml) and storm flow (N: 1.93 mg/L versus 0.36 mg/L, and FC: 1600 versus 167 MPN/100 ml). Fecal coliform bacteria in urbanized areas consistently exceeded the US EPA's review criterion for recreational waters during both base flow and to a greater extent storm flow. During phase 2, regression models were tested based on data from six newly chosen watersheds with similar land use/cover patterns. Lastly, theoretical watersheds, based on land use percentages, were created to illustrate trends in water quality impairment as land development occurs. The models developed from this research could be used to forecast water quality changes under various land use scenarios in the developing Piedmont region of the US.

Quantification of urban structure on building block level utilizing multisensoral remote sensing data

NASA Astrophysics Data System (ADS)

Wurm, Michael; Taubenböck, Hannes; Dech, Stefan

2010-10-01

Dynamics of urban environments are a challenge to a sustainable development. Urban areas promise wealth, realization of individual dreams and power. Hence, many cities are characterized by a population growth as well as physical development. Traditional, visual mapping and updating of urban structure information of cities is a very laborious and cost-intensive task, especially for large urban areas. For this purpose, we developed a workflow for the extraction of the relevant information by means of object-based image classification. In this manner, multisensoral remote sensing data has been analyzed in terms of very high resolution optical satellite imagery together with height information by a digital surface model to retrieve a detailed 3D city model with the relevant land-use / land-cover information. This information has been aggregated on the level of the building block to describe the urban structure by physical indicators. A comparison between the indicators derived by the classification and a reference classification has been accomplished to show the correlation between the individual indicators and a reference classification of urban structure types. The indicators have been used to apply a cluster analysis to group the individual blocks into similar clusters.

Urbanization and Land Use Changes in Peri-Urban Area using Spatial Analysis Methods (Case Study: Ciawi Urban Areas, Bogor Regency)

NASA Astrophysics Data System (ADS)

Cahya, D. L.; Martini, E.; Kasikoen, K. M.

2018-02-01

Urbanization is shown by the increasing percentage of the population in urban areas. In Indonesia, the percentage of urban population increased dramatically form 17.42% (1971) to 42.15% (2010). This resulted in increased demand for housing. Limited land in the city area push residents looking for an alternative location of his residence to the peri-urban areas. It is accompanied by a process of land conversion from green area into built-up area. Continuous land conversion in peri-urban area is becoming increasingly widespread. Bogor Regency as part of the Jakarta Metropolitan Area is experiencing rapid development. This regency has been experienced land-use change very rapidly from agricultural areas into urban built up areas. Aim of this research is to analyze the effect of urbanization on land use changes in peri-urban areas using spatial analysis methods. This research used case study of Ciawi Urban Area that experiencing rapid development. Method of this research is using descriptive quantitative approach. Data used in this research is primary data (field survey) and secondary data (maps). To analyze land use change is using Geographic Information System (GIS) as spatial analysis methods. The effect of urbanization on land use changes in Ciawi Urban Area from year 2013 to 2015 is significant. The reduction of farm land is around -4.00% and wetland is around - 2.51%. The increasing area for hotel/villa/resort is around 3.10%. Based on this research, local government (Bogor Regency) should be alert to the land use changes that does not comply with the land use plan and also consistently apply the spatial planning.

Characterizing land subsidence mechanisms as a function of urban basin geohazards using space geodesy

NASA Astrophysics Data System (ADS)

Bawden, G. W.

2016-12-01

Land subsidence in urban basins will likely become a more significant geohazard in many of the global sedimentary basins as population growth, resource availability, and climate change compound natural and anthropogenic contributors that influence basin elevation. Coastal basins are at the greatest risk where land subsidence is additive to sea level rise, thereby increasing the rate of exposure to coastal populations. Land surface elevation change is a function of many different parameters, including: elastic and inelastic surface response to managed and natural groundwater levels; anthropogenic activities (hydrocarbon extraction, wastewater injection, fracking, geothermal production, and mass redistribution); local tectonic deformation and regional tectonic drivers (such as repeated uplift and subsidence cycles above subduction zones); climate change (influencing the timing, magnitude, nature and duration of seasonal/annual precipitation and permafrost extent); material properties of the basin sediments (influencing susceptibility to soil compaction, oxidization, and dissolution); post glacial rebound; isostatic flexure associated with sea-level and local mass changes; and large scale gravitational processes (such as growth faults and landslides). Geodetic measurements, such as InSAR and GPS, help track spatial and temporal changes in both relative and absolute basin elevation thereby helping to characterize the mechanism(s) driving the geohazards. In addition to a number of commercial radar satellites, European Space Agency's Sentinel-1a/b satellites are beginning to provide a wealth of data over many basin targets with C-band (5.5 cm wavelength). The NISAR (NASA-ISRO Synthetic Aperture Radar) L-band (24 cm wavelength) mission (anticipated 2021 launch) will image nearly every basin globally every 12 days and data from the mission will help characterize land subsidence and many other solid-Earth and hydrologic geohazards that impact urban basins.

The Evaluation of Screening Process and Local Bureaucracy in Determining the Priority of Urban Roads Maintenance and Rehabilitation

NASA Astrophysics Data System (ADS)

Hendhratmoyo, Andri; Syafi'i; Pungky Pramesti, Florentina

2017-11-01

Due to the limited budget of urban roads maintenance and rehabilitation, its prioritizationis inevitable. Many models have been developed to solve these problems. That is the reason why the purpose of this study was to evaluate the screening process in the decision making of the urban roads maintenance and rehabilitation priority. The prioritization that have to be taken into account on the effect of important criteria are road condition, traffic volume, budget processing and land use. 30 stakeholders were asked to fill in the questionnaires. The object of this case study are 188 urban roads sections at Ponorogo in order to examine the priorities. The researchers collected the data from Surface Distress Index (SDI), traffic volume, budget processing and land use of these road sections. Based on analysis, the weights of the criteria were: road condition (W1) = 0,411; traffic volume (W2) = 0,122; budget processing (W3) = 0,363 and land use (W4) = 0,105. The result of this study by the comparison of the index values of the alternatives priorities, Nyi Ageng Serang Street, was revealed to have the highest priority over the other streets regarding of maintenance and rehabilitation activities.

Extraction and Analysis of Mega Cities’ Impervious Surface on Pixel-based and Object-oriented Support Vector Machine Classification Technology: A case of Bombay

NASA Astrophysics Data System (ADS)

Yu, S. S.; Sun, Z. C.; Sun, L.; Wu, M. F.

2017-02-01

The object of this paper is to study the impervious surface extraction method using remote sensing imagery and monitor the spatiotemporal changing patterns of mega cities. Megacity Bombay was selected as the interesting area. Firstly, the pixel-based and object-oriented support vector machine (SVM) classification methods were used to acquire the land use/land cover (LULC) products of Bombay in 2010. Consequently, the overall accuracy (OA) and overall Kappa (OK) of the pixel-based method were 94.97% and 0.96 with a running time of 78 minutes, the OA and OK of the object-oriented method were 93.72% and 0.94 with a running time of only 17s. Additionally, OA and OK of the object-oriented method after a post-classification were improved up to 95.8% and 0.94. Then, the dynamic impervious surfaces of Bombay in the period 1973-2015 were extracted and the urbanization pattern of Bombay was analysed. Results told that both the two SVM classification methods could accomplish the impervious surface extraction, but the object-oriented method should be a better choice. Urbanization of Bombay experienced a fast extending during the past 42 years, implying a dramatically urban sprawl of mega cities in the developing countries along the One Belt and One Road (OBOR).

The Effects of a Changing Climate and Urbanisation on River Flows in the Thames Basin, UK - a Hydrological Modelling Approach

NASA Astrophysics Data System (ADS)

Miller, J. D.; Rickards, N. J.; Kjeldsen, T. R.; Hutchins, M.; Rowland, C.; Prudhomme, C.; Maliko, T.; Fidal, J.; Hagen-Zanker, A.

2016-12-01

The UK population is set to increase by 16% by 2035; it is therefore increasingly important to understand the impact this may have on urban populations, and in turn how this will affect river flow regimes and water quality in urban areas. A growing population is likely to lead to an increase in urban land use and impervious surfaces, the implications of which are not yet fully understood for issues such as future flood risk. The aim of this paper is to develop a greater understanding of the impacts of both an increasing population and urban extent in the context of a changing climate, and to assess the effect these may have on urban streamflow regimes and water security in the future. Flows are modelled for selected catchments in the Thames basin using URBMOD, a lumped rainfall runoff model that is able to represent both pervious and impervious surfaces, reducing infiltration in catchments where there is a greater urban extent. The model uses daily catchment average rainfall and evapotranspiration derived from gridded data, and is calibrated against long-term river flow records. Historic satellite imagery is used to train cellular automata land use models, which are then applied under different scenarios of urban development up to 2035. These changes in land use are combined with a range of climate change scenarios to give an indication of how urban flow regimes may be altered in the Thames basin over the next 20 years. Results suggest an intensification of the hydrological regime in the majority of catchments, with increases in high flow magnitudes (Q10) of up to 5%. The trend for low flows (Q90) is less clear, with some catchments displaying reductions of around 4%, whilst others show slight increased flows. We identify the main drivers behind these changes, from which the fine-scale impacts of urbanisation on water resources can be better understood. Research findings are being used to inform a regional-scale model, coupling water quantity and quality and providing insight to urban planners and stakeholders on the future urban hydrological regime in the Thames basin. Similar approaches are being used to assess impacts of anthropogenic drivers on water resources in the Cauvery basin in India, whereby the applicability of the model under very different climate and urban morphology will be tested.

Strengthening Carbon Sinks in Urban Soils to Mitigate and Adapt to Climate Change (Invited)

NASA Astrophysics Data System (ADS)

Lorenz, K.

2010-12-01

Urban lands comprise the most intensively transformed lands on earth. Urban land cover changed from 0.01% of the global ice-free land area in 1700 to 0.5% in 2002. Globally, urbanization is now the primary process of land cover transformation. Urbanization accentuates conversion of natural or agricultural lands to urban soils with altered biological, chemical and physical properties. Soil functions particularly important in urban ecosystems are the protection against damages by intense precipitation and flooding, retention and immobilization of contaminants, production of clean water, and buffering of climate extremes, mainly through evaporative cooling. Because of their disturbance by human activities, urban soils have distinct properties. In contrast to natural soils, human-made materials dominate or strongly influence urban soils as human activities constitute important soil-forming factors in urban ecosystems. Soils whose properties and pedogenesis are dominated by their technical origin are classified as Technosols in the World Reference Base (WRB) for Soil Resources. They contain large proportions of artifacts, or are sealed by technic hard rock. Technosols include soils from wastes (e.g., landfills, sludge, cinders, mine spoils and ashes), pavements with their underlying unconsolidated materials, soils with geomembranes and constructed soils in human-made materials. However, Technosols and their properties have not yet been studied extensively. Yet, a greater understanding of urban soil properties is urgently needed to assess their biogeochemical cycles and role in the global carbon (C) cycle, and to manage their ecosystem services for the well-being of the urban population. Studies of biogeochemical cycles in urban soils of Stuttgart, Germany, have shown that soils from as deep as 1.9-m depth contain significant amounts of microbial biomass and are metabolically active. Buried organic matter (OM) rich artifacts where frequently observed originating from a long industrial history and devastations during World War II. In most surface soils in Stuttgart, however, OM was dominated by plant litter derived compounds but in one urban soil anthropogenic OM and black carbon (BC) dominated soil organic carbon (SOC) as indicated by bloch decay solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Artifacts such as municipal solid waste, construction waste, and fragments of charcoal, coal and glass were also found in urban forest soil profiles to 1-m depth in Columbus, OH. To this depth, about 150 Mg SOC ha-1 were stored and, thus, more than in urban forest soils of Baltimore, MD, and New York City, NY. However, the contribution of litter derived vs. artifact derived OM compounds such as BC has not been assessed for urban soils in the U.S.. In summary, studies on biogeochemical cycles in urban ecosystems must include the entire soil profile as anthropogenic activities may create Technosols with properties not encountered in soils of natural ecosystems. As urban ecosystems are major sources of atmospheric carbon dioxide (CO2), Technosols may be tailor-made to imitate natural soils with high SOC pools and long carbon mean residence times. Thus, the C sink in urban soils must be strengthened to mitigate and adapt urban ecosystems to abrupt climate change.

New baseline environmental assessment of mosquito ecology in northern Haiti during increased urbanization

PubMed Central

Archer, Reginald S.; Alimi, Temitope O.; Arheart, Kristopher K.; Impoinvil, Daniel E.; Oscar, Roland; Fuller, Douglas O.; Qualls, Whitney A.

2015-01-01

The catastrophic 2010 earthquake in Port-au-Prince, Haiti, led to the large-scale displacement of over 2.3 million people, resulting in rapid and unplanned urbanization in northern Haiti. This study evaluated the impact of this unplanned urbanization on mosquito ecology and vector-borne diseases by assessing land use and change patterns. Land-use classification and change detection were carried out on remotely sensed images of the area for 2010 and 2013. Change detection identified areas that went from agricultural, forest, or bare-land pre-earthquake to newly developed and urbanized areas post-earthquake. Areas to be sampled for mosquito larvae were subsequently identified. Mosquito collections comprised five genera and ten species, with the most abundant species being Culex quinquefasciatus 35% (304/876), Aedes albopictus 27% (238/876), and Aedes aegypti 20% (174/876). All three species were more prevalent in urbanized and newly urbanized areas. Anopheles albimanus, the predominate malaria vector, accounted for less than 1% (8/876) of the collection. A set of spectral indices derived from the recently launched Landsat 8 satellite was used as covariates in a species distribution model. The indices were used to produce probability surfaces maps depicting the likelihood of presence of the three most abundant species within 30 m pixels. Our findings suggest that the rapid urbanization following the 2010 earthquake has increased the amount of area with suitable habitats for urban mosquitoes, likely influencing mosquito ecology and posing a major risk of introducing and establishing emerging vector-borne diseases. PMID:26047183

Exploring the mid-infrared region for urban remote sensing: seasonal and view angle effects

NASA Astrophysics Data System (ADS)

Krehbiel, C. P.; Kovalskyy, V.; Henebry, G. M.

2013-12-01

Spanning 3-5 microns, the mid-infrared (MIR) region is the mixing zone between reflected sunlight and emitted earthlight in roughly equal proportions. While the MIR has been utilized in atmospheric remote sensing, its potential in terrestrial remote sensing--particularly urban remote sensing, has yet to be realized. One major advantage of the MIR is the ability to penetrate most anthropogenic haze and smog. Green vegetation appears MIR-dark, urban building materials appear MIR-grey, and bare soil and dried vegetation appear MIR-bright. Thus, there is an intrinsic seasonality in MIR radiance dynamics due both to surface type differences and to seasonal change in insolation. These factors merit exploration into the potential applications of the MIR for monitoring urban change. We investigated MIR radiance dynamics in relation to (1) the spectral properties of land cover types, (2) time of year and (3) sensor view zenith angle (VZA). We used Aqua MODIS daily swaths for band 23 (~ 4.05 μm) at 1 km spatial resolution from 2009-2010 and the NLCD Percent Impervious Surface Area (%ISA) 30 m product from 2001 and 2006. We found the effects of time of year, sensor VZA, and %ISA to be three principal factors influencing MIR radiance dynamics. We focused on analyzing the relationship between MIR radiance and %ISA over eight major cities in the Great Plains of the USA. This region is characterized by four distinct seasons, relatively flat terrain, and isolated urban centers situated within a vegetated landscape. We used west-east transects beginning in the agricultural areas outside of each city, passing through the urban core and extending back out into the agricultural periphery to observe the spatial pattern of MIR radiance and how it changes seasonally. Sensor VZA influences radiance dynamics by affecting the proportion of surface elements detected--especially pertinent at the coarse spatial resolution (~1 km) of MODIS. For example, smaller VZAs (<30°) capture more spatial detail than larger VZAs (>30°). Larger VZAs detect a larger proportion of crop canopies and less soil surface, and thus generally exhibit lower radiance and less variation than smaller VZAs. Future work should focus on how best to account for (1) land surface phenology, (2) the proportion of impervious surface, and (3) sensor viewing geometry to generate high signal-to-noise ratio composites and advance change detection and urban growth monitoring.

Monitoring Urban Land Cover/land Use Change in Algiers City Using Landsat Images (1987-2016)

NASA Astrophysics Data System (ADS)

Bouchachi, B.; Zhong, Y.

2017-09-01

Monitoring the Urban Land Cover/Land Use change detection is important as one of the main driving forces of environmental change because Urbanization is the biggest changes in form of Land, resulting in a decrease in cultivated areas. Using remote sensing ability to solve land resources problems. The purpose of this research is to map the urban areas at different times to monitor and predict possible urban changes, were studied the annual growth urban land during the last 29 years in Algiers City. Improving the productiveness of long-term training in land mapping, were have developed an approach by the following steps: 1) pre-processing for improvement of image characteristics; 2) extract training sample candidates based on the developed methods; and 3) Derive maps and analyzed of Algiers City on an annual basis from 1987 to 2016 using a Supervised Classifier Support Vector Machine (SVMs). Our result shows that the strategy of urban land followed in the region of Algiers City, developed areas mostly were extended to East, West, and South of Central Regions. The urban growth rate is linked with National Office of Statistics data. Future studies are required to understand the impact of urban rapid lands on social, economy and environmental sustainability, it will also close the gap in data of urbanism available, especially on the lack of reliable data, environmental and urban planning for each municipality in Algiers, develop experimental models to predict future land changes with statistically significant confidence.

Introducing MISR Version 23: Resolution and Content Improvements to MISR Aerosol and Land Surface Product

NASA Astrophysics Data System (ADS)

Garay, M. J.; Bull, M. A.; Witek, M. L.; Diner, D. J.; Seidel, F.

2017-12-01

Since early 2000, the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite has been providing operational Level 2 (swath-based) aerosol optical depth (AOD) and particle property retrievals at 17.6 km spatial resolution and atmospherically corrected land surface products at 1.1 km resolution. A major, multi-year development effort has led to the release of updated operational MISR Level 2 aerosol and land surface retrieval products. The spatial resolution of the aerosol product has been increased to 4.4 km, allowing more detailed characterization of aerosol spatial variability, especially near local sources and in urban areas. The product content has been simplified and updated to include more robust measures of retrieval uncertainty and other fields to benefit users. The land surface product has also been updated to incorporate the Version 23 aerosol product as input and to improve spatial coverage, particularly over mountainous terrain and snow/ice-covered surfaces. We will describe the major upgrades incorporated in Version 23, present validation of the aerosol product, and describe some of the applications enabled by these product updates.

Evaluation of an atmospheric model with surface and ABL meteorological data for energy applications in structured areas

NASA Astrophysics Data System (ADS)

Triantafyllou, A. G.; Kalogiros, J.; Krestou, A.; Leivaditou, E.; Zoumakis, N.; Bouris, D.; Garas, S.; Konstantinidis, E.; Wang, Q.

2018-03-01

This paper provides the performance evaluation of the meteorological component of The Air Pollution Model (TAPM), a nestable prognostic model, in predicting meteorological variables in urban areas, for both its surface layer and atmospheric boundary layer (ABL) turbulence parameterizations. The model was modified by incorporating four urban land surface types, replacing the existing single urban surface. Control runs were carried out over the wider area of Kozani, an urban area in NW Greece. The model was evaluated for both surface and ABL meteorological variables by using measurements of near-surface and vertical profiles of wind and temperature. The data were collected by using monitoring surface stations in selected sites as well as an acoustic sounder (SOnic Detection And Ranging (SODAR), up to 300 m above ground) and a radiometer profiler (up to 600 m above ground). The results showed the model demonstrated good performance in predicting the near-surface meteorology in the Kozani region for both a winter and a summer month. In the ABL, the comparison showed that the model's forecasts generally performed well with respect to the thermal structure (temperature profiles and ABL height) but overestimated wind speed at the heights of comparison (mostly below 200 m) up to 3-4 ms-1.

The Need for High Spatial Resolution Multispectral Thermal Remote Sensing Data In Urban Heat Island Research

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.; Luvall, Jeffrey C.

2006-01-01

Although the study of the Urban Heat Island (UHI) effect dates back to the early 1800's when Luke Howard discovered London s heat island, it has only been with the advent of thermal remote sensing systems that the extent, characteristics, and impacts of the UHI have become to be understood. Analysis of the UHI effect is important because above all, this phenomenon can directly influence the health and welfare of urban residents. For example, in 1995, over 700 people died in Chicago due to heat-related causes. UHI s are characterized by increased temperature in comparison to rural areas and mortality rates during a heat wave increase exponentially with the maximum temperature, an effect that is exacerbated by the UHI. Aside from the direct impacts of the UHI on temperature, UHI s can produce secondary effects on local meteorology, including altering local wind patterns, increased development of clouds and fog, and increasing rates of precipitation either over, or downwind, of cities. Because of the extreme heterogeneity of the urban surface, in combination with the sprawl associated with urban growth, thermal infrared (TIR) remote sensing data have become of significant importance in understanding how land cover and land use characteristics affect the development and intensification of the UHI. TIR satellite data have been used extensively to analyze the surface temperature regimes of cities to help observe and measure the impacts of surface temperatures across the urban landscape. However, the spatial scales at which satellite TIR data are collected are for the most part, coarse, with the finest readily available TIR data collected by the Landsat ETM+ sensor at 60m spatial resolution. For many years, we have collected high spatial resolution (10m) data using an airborne multispectral TIR sensor over a number of cities across the United States. These high resolution data have been used to develop an understanding of how discrete surfaces across the urban environment (e.g., rooftops, pavements) interact from a surface-lower atmosphere energy flux perspective, to force the development of the UHI. Moreover, the airborne TIR sensor we used in our UHI studies was a multispectral sensor that had six channels in the 8-12pm range. The advantages of collecting multispectral TIR data became readily evident as a valuable tool for better calculation of unique surface thermal energy responses for urban materials over the 8-12 micrometer region, and also for getting a better handle on surface emissivity characteristics for these discrete surfaces. In this presentation, we will provide evidence on the virtues of how high spatial resolution multispectral TIR data can provide for better analysis of the UHI that cannot now be attained via TIR data obtained from satellites. Furthermore, we wish to provide compelling evidence on why future TIR satellite sensors should collect data at fine spatial resolutions (e.g. less than or equal to 30m) to better allow for measurement of surface thermal energy fluxes from discrete urban surfaces, and to better understand how surface fluxes from different urban materials in cities around the world in different climatic regimes, affect development of the UHI characteristics.

Variation in surface water-groundwater exchange with land use in an urban stream

NASA Astrophysics Data System (ADS)

Ryan, Robert J.; Welty, Claire; Larson, Philip C.

2010-10-01

SummaryA suite of methods is being utilized in the Baltimore metropolitan area to develop an understanding of the interaction between groundwater and surface water at multiple space and time scales. As part of this effort, bromide tracer experiments were conducted over two 10-day periods in August 2007 and May 2008 along two sections (each approximately 900 m long) of Dead Run, a small urban stream located in Baltimore County, Maryland, to investigate the influence of distinct zones of riparian land cover on surface-subsurface exchange and transient storage under low and high baseflow conditions. Riparian land cover varied by reach along a gradient of land use spanning parkland, suburban/residential, commercial, institutional, and transportation, and included wooded, meadow, turf grass, and impervious cover. Under summer low baseflow conditions, surface water-groundwater exchange, defined by gross inflow and gross outflow, was larger and net inflow (gross inflow minus gross outflow) had greater spatial variability, than was observed under spring high baseflow conditions. In addition, the fraction of nominal travel time attributable to transient storage ( Fmed) was lower and was more spatially variable under high baseflow conditions than under low baseflow conditions. The influence of baseflow condition on surface water-ground water exchange and transient storage was most evident in the subreaches with the least riparian forest cover and these effects are attributed to a lack of shading in reaches with little riparian forest cover. We suggest that under summer low baseflow conditions, the lack of shading allowed excess in-channel vegetation growth which acted as a transient storage zone and a conduit for outflow (i.e. uptake and evapotranspiration). Under spring high baseflow conditions the transient storage capacity of the channel was reduced because there was little in-channel vegetation.

Urban Land Cover Type Influences CO2 Fluxes within Phoenix, Arizona

NASA Astrophysics Data System (ADS)

Perez-Ruiz, E. R.; Vivoni, E. R.; Templeton, N. P.

2017-12-01

Urbanization is accompanied by the modification of land surface characteristics that should have an impact on local energy, water and carbon cycles. For instance, despite their relative small land area, cities are responsible for more than 70% of the global anthropogenic CO2 emissions. Nevertheless, relatively little is known on the dynamics of urban carbon fluxes or net ecosystem exchange (NEE), in particular over the multitude of land cover patches present within cities. In this study, we present a comparison of NEE measurements in four urban patches in the Phoenix metropolitan area. A mobile eddy covariance (EC) tower was deployed at a xeric landscaping, a parking lot and a mesic landscaping during consecutive, short-term ( 40 days) sampling periods and compared to a reference site (REF) in a suburban neighborhood over a longer deployment ( 9 months). Based on the datasets, we analyze the diurnal cycle and the daily and seasonal variations of NEE in the context of the measured meteorological conditions, including the surface energy budget. EC observations were then related to vegetation conditions through a satellite-based Normalized Difference Vegetation Index (NDVI) and to anthropogenic activities through local traffic counts. All deployment sites showed important differences in NEE with respect to the REF location due to the influence of the urban patch area sampled within the EC footprint. Daily NEE values at all sites exhibited differences among days of the week that were linked to traffic conditions, with higher values during weekdays and lower values during weekends. The diurnal behavior of NEE showed different trends depending on the amount of vegetation and the proximity to nearby roads. Minimum midday (around noon) values of NEE were noted where urban plants absorbed CO2, while maximum peaks of NEE occurred during rush hours (around 8 am and 6 pm) where the traffic influence was high. Overall, three of the four sites with low to moderate vegetation acted as a net source of CO2 during the respective deployments, while one site with a well-irrigated mesic landscaping acted as a net sink of CO2 during the summer. Thus, the characteristics and function of urban patches should have a strong control on the CO2 fluxes within cities, which can be reliably measured using the EC method.

Remote sensing, land use, and demography - A look at people through their effects on the land

NASA Technical Reports Server (NTRS)

Paul, C. K.; Landini, A. J.

1976-01-01

Relevant causes of failure by the remote sensing community in the urban scene are analyzed. The reasons for the insignificant role of remote sensing in urban land use data collection are called the law of realism, the incompatibility of remote sensing and urban management system data formats is termed the law of nominal/ordinal systems compatibility, and the land use/population correlation dilemma is referred to as the law of missing persons. The study summarizes the three laws of urban land use information for which violations, avoidance, or ignorance have caused the decline of present remote sensing research. Particular attention is given to the rationale for urban land use information and for remote sensing. It is shown that remote sensing of urban land uses compatible with the three laws can be effectively developed by realizing the 10 percent contribution of remote sensing to urban land use planning data collection.

Interaction between Cities and Climate Change: Modelling Urban Morphology and Local Urban Planning Scenarios from Open Datasets across European Cities

NASA Astrophysics Data System (ADS)

Thomas, Bart; Stevens, Catherine; Grommen, Mart

2015-04-01

Cities are characterised by a large spatiotemporal diversity of local climates induced by a superposition of various factors and processes interacting at global and regional scales but also at the micro level such as the urban heat island effect. As urban areas are known as 'hot spots' prone to climate and its variability over time leading to changes in the severity and occurrence of extreme events such as heat waves, it is of crucial importance to capture the spatial heterogeneity resulting from variations in land use land cover (LULC) and urban morphology in an effective way to drive local urban climate simulations. The first part of the study conducted in the framework of the NACLIM FP7 project funded by the European Commission focusses on the extraction of land surface parameters linked to urban morphology characteristics from detailed 3D city models and their relationship with openly accessible European datasets such as the degree of soil sealing and disaggregated population densities from the European Environment Agency (EEA) and the Joint Research Centre (JRC). While it has been demonstrated that good correlations can be found between those datasets and the planar and frontal area indices, the present work has expanded the research to other urban morphology parameters including the average and variation of the building height and the sky view factor. Correlations up to 80% have been achieved depending on the considered parameter and the specific urban area including the cities of Antwerp (Belgium), Berlin (Germany) and Almada (Portugal) represented by different climate and urban characteristics. Moreover, the transferability of the established relations has been investigated across the various cities. Secondly, a flexible and scalable approach as a function of the required the level of detail has been elaborated to update the various morphology parameters in case of integration with urban planning data to analyse the local impact of future land use scenarios, climate adaptation strategies and mitigation measures in an effective way by comparing the future occupation of the soil against metrics derived from existing soil sealing data from the EEA.

24 CFR 1710.209 - Title and land use.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Title and land use. 1710.209 Section 1710.209 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.107 - Risks of buying land.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Risks of buying land. 1710.107 Section 1710.107 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.209 - Title and land use.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Title and land use. 1710.209 Section 1710.209 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.107 - Risks of buying land.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Risks of buying land. 1710.107 Section 1710.107 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.107 - Risks of buying land.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Risks of buying land. 1710.107 Section 1710.107 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.209 - Title and land use.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Title and land use. 1710.209 Section 1710.209 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

24 CFR 1710.209 - Title and land use.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Title and land use. 1710.209 Section 1710.209 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION Reporting Requirements...

The implementation of biofiltration systems, rainwater tanks and urban irrigation in a single-layer urban canopy model

NASA Astrophysics Data System (ADS)

Demuzere, Matthias; Coutts, Andrew; Goehler, Maren; Broadbent, Ashley; Wouters, Hendrik; van Lipzig, Nicole; Gebert, Luke

2015-04-01

Urban vegetation is generally considered as a key tool to modify the urban energy balance through enhanced evapotranspiration (ET). Given that vegetation is most effective when it is healthy, stormwater harvesting and retention strategies (such as water sensitive urban design) could be used to support vegetation and promote ET. This study presents the implementation of a vegetated lined bio-filtration system (BFS) combined with a rainwater tank (RWT) and urban irrigation system in the single-layer urban canopy model Community Land Model-Urban. Runoff from roof and impervious road surface fractions is harvested and used to support an adequate soil moisture level for vegetation in the BFS. In a first stage, modelled soil moisture dynamics are evaluated and found reliable compared to observed soil moisture levels from biofiltration pits in Smith Street, Melbourne (Australia). Secondly, the impact of BFS, RWT and urban irrigation on ET is illustrated for a two-month period in 2012 using varying characteristics for all components. Results indicate that (i) a large amount of stormwater is potentially available for indoor and outdoor water demands, including irrigation of urban vegetation, (ii) ET from the BFS is an order of magnitude larger compared to the contributions from the impervious surfaces, even though the former only covers 10% of the surface fraction and (iii) attention should be paid to the cover fraction and soil texture of the BFS, size of the RWT and the surface fractions contributing to the collection of water in the RWT. Overall, this study reveals that this model development can effectuate future research with state-of-the-art urban climate models to further explore the benefits of vegetated biofiltration systems as a water sensitive urban design tool optimised with an urban irrigation system to maintain healthy vegetation.

Influences of Urban Expansion on Cultivated Lands in China Since 1970S

NASA Astrophysics Data System (ADS)

Liu, F.; Zhang, Z.; Zhao, X.; Yu, S.; Wang, X.; Zuo, L.

2018-04-01

Urban expansion has far-reaching influences on cultivated lands, and has a serious effect on grain output and safety. However, relatively little attention has been paid to monitor cultivated land losses through urban expansion over a long timeframe and multi-frequency, especially its differences on national scale systematically. In this work, the characteristics of Chinese cultivated land dynamics were described using annual occupied area per city, contribution rate of cultivated lands to urban expansion and the classification method of basic trend of cultivated land losses. Results indicate that: (1) in the past four decades, large amount of cultivated lands have been occupied during the urban expansion process, and have become the first land source for Chinese urban expansion. (2) Cultivated land loss among municipalities, provincial capitals and other cities was obviously different. The higher of cities' administrative level was, the more obvious of cultivated land loss in these cities appeared, and the earlier of acceleration loss stage of cultivated lands occurred. (3) Cultivated land loss in five population-size cities was unbalanced, representing obviously different loss process and contribution on urban expansion. The bigger of cities' population size was, the more obvious of cultivated land loss in these cities appeared, and the earlier of acceleration loss stage of cultivated lands occurred. (4) Cultivated land losses during urban expansion process were imbalanced in China, and were classified into seven trends. (5) Chinese cultivated land protection has been carried out from the awakening stage to the deep implementation stage.

Linking land cover and water quality in New York City's water supply watersheds.

PubMed

Mehaffey, M H; Nash, M S; Wade, T G; Ebert, D W; Jones, K B; Rager, A

2005-08-01

The Catskill/Delaware reservoirs supply 90% of New York City's drinking water. The City has implemented a series of watershed protection measures, including land acquisition, aimed at preserving water quality in the Catskill/Delaware watersheds. The objective of this study was to examine how relationships between landscape and surface water measurements change between years. Thirty-two drainage areas delineated from surface water sample points (total nitrogen, total phosphorus, and fecal coliform bacteria concentrations) were used in step-wise regression analyses to test landscape and surface-water quality relationships. Two measurements of land use, percent agriculture and percent urban development, were positively related to water quality and consistently present in all regression models. Together these two land uses explained 25 to 75% of the regression model variation. However, the contribution of agriculture to water quality condition showed a decreasing trend with time as overall agricultural land cover decreased. Results from this study demonstrate that relationships between land cover and surface water concentrations of total nitrogen, total phosphorus, and fecal coliform bacteria counts over a large area can be evaluated using a relatively simple geographic information system method. Land managers may find this method useful for targeting resources in relation to a particular water quality concern, focusing best management efforts, and maximizing benefits to water quality with minimal costs.

Water-quality characteristics of urban runoff and estimates of annual loads in the Tampa Bay area, Florida, 1975-80

USGS Publications Warehouse

Lopez, M.A.; Giovannelli, R.F.

1984-01-01

Rainfall, runoff, and water quality data were collected at nine urban watersheds in the Tampa Bay area from 1975 to 1980. Watershed drainage area ranged from 0.34 to 0.45 sq mi. Land use was mixed. Development ranged from a mostly residential watershed with a 19% impervious surface, to a commercial-residential watershed with a 61% impervious surface. Average biochemical oxygen demand concentrations of base flow at two sites and of stormwater runoff at five sites exceeded treated sewage effluent standards. Average coliform concentrations of stormwater runoff at all sites were several orders of magnitude greater than standards for Florida Class III receiving water (for recreation or propagation and management of fish and wildlife). Average concentrations of lead and zinc in stormwater runoff were consistently higher than Class III standards. Stormwater-runoff loads and base-flow concentrations of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus, and lead were related to runoff volume, land use, urban development, and antecedent daily rainfall by multiple linear regression. Stormwater-runoff volume was related to pervious area, hydraulically connected impervious surfaces, storm rainfall, and soil-infiltration index. Base-flow daily discharge was related to drainage area and antecedent daily rainfall. The flow regression equations of this report were used to compute 1979 water-year loads of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus , and total lead for the nine Tampa Bay area urban watersheds. (Lantz-PTT)

Urban Runoff and Nutrients Loading Control from Sustainable BMPs (Invited)

NASA Astrophysics Data System (ADS)

Xiao, Q.

2009-12-01

Climate change alters hydrodynamic and nutrient dynamic in both large and small geographic scales. These changes in our freshwater system directly affect drinking water, food production, business, and all aspects of our life. Along with climate change is increasing urbanization which alters natural landscape. Urban runoff has been identified as one of many potential drivers of the decline of pelagic fishes in san Francisco Bay-Delta region. Recent found of Pyrethroids in American River has increased scientists, public, and policy makers’ concern about our fresh water system. Increasing our understanding about the fundamental hydrodynamic, nutrient dynamics, and the transport mechanics of runoff and nutrients are important for future water resource and ecosystem management. Urbanization has resulted in significantly increasing the amount of impervious land cover. Most impervious land covers are hydrophobic that alters surface runoff because of the effects on surface retention storage, rainfall interception, and infiltration. Large volumes of excess storm runoff from urbanized areas cause flooding, water pollution, groundwater recharge deficits, destroyed habitat, beach closures, and toxicity to aquatic organisms. Parking lot alone accounts for more than 11% of these impervious surfaces. Contrast to impervious parking lot, turfgrass can accouter for 12% of urban land in California. Irrigated urban landscapes create considerable benefits to our daily living. However, the use of fertilizers and pesticides has caused environmental problems. Preventing fertilizers and pesticides from entering storm drains is an important goal for both landscape and storm runoff managers. Studies of urban runoff have found that the most fertilizers and pesticides are from dry weather runoff which conveys pollutants to sidewalks, streets, and storm drains. Controlling surface runoff is critical to preventing these pollutants from entering storm drains and water bodies. Large scale construction of runoff retention basins and treatment facilities to meet TMDL (Total Maximum Daily Load) regulations are not cost-effective or practical. An alternative approach is to control runoff and nutrients on-site through installation of decentralized BMPs that detain and infiltrate runoff before it reaches storm drains. Recent developed green-infrastructure which integrating engineered soil and trees to reduce runoff and nutrients loading is a self-sustained best management practice (BMP). This BMP has been testing and used in urban runoff control. In Davis, CA this type of BMPs were installed in a parking lot and a residential property to evaluate the system’s effectiveness on reducing storm runoff and pollutant loading from the parking lot and irrigated landscape. Storm runoff and pollutant loading were measured and monitored during February 2007 thru May 2009 from the parking lot. The BMP reduced surface runoff and nutrients by 88.8% and 95.3%, respectively. In the residential irrigated landscape, the dry-weather runoff was monitored during 2007 irrigation season, the BMP captured almost all dry weather runoff. The performance of these BMPs demonstrated their potential use for reducing runoff and nutrients loading. Control urban runoff from these 23% landscape (i.e., parking lot and irrigated turf grass) could largely alter the runoff and nutrients transport and their dynamic in our water system.

Evaluating Vegetation Type Effects on Land Surface Temperature at the City Scale

NASA Astrophysics Data System (ADS)

Wetherley, E. B.; McFadden, J. P.; Roberts, D. A.

2017-12-01

Understanding the effects of different plant functional types and urban materials on surface temperatures has significant consequences for climate modeling, water management, and human health in cities. To date, doing so at the urban scale has been complicated by small-scale surface heterogeneity and limited data. In this study we examined gradients of land surface temperature (LST) across sub-pixel mixtures of different vegetation types and urban materials across the entire Los Angeles, CA, metropolitan area (4,283 km2). We used AVIRIS airborne hyperspectral imagery (36 m resolution, 224 bands, 0.35 - 2.5 μm) to estimate sub-pixel fractions of impervious, pervious, tree, and turfgrass surfaces, validating them with simulated mixtures constructed from image spectra. We then used simultaneously imaged LST retrievals collected at multiple times of day to examine how temperature changed along gradients of the sub-pixel mixtures. Diurnal in situ LST measurements were used to confirm image values. Sub-pixel fractions were well correlated with simulated validation data for turfgrass (r2 = 0.71), tree (r2 = 0.77), impervious (r2 = 0.77), and pervious (r2 = 0.83) surfaces. The LST of pure pixels showed the effects of both the diurnal cycle and the surface type, with vegetated classes having a smaller diurnal temperature range of 11.6°C whereas non-vegetated classes had a diurnal range of 16.2°C (similar to in situ measurements collected simultaneously with the imagery). Observed LST across fractional gradients of turf/impervious and tree/impervious sub-pixel mixtures decreased linearly with increasing vegetation fraction. The slopes of decreasing LST were significantly different between tree and turf mixtures, with steeper slopes observed for turf (p < 0.05). These results suggest that different physiological characteristics and different access to irrigation water of urban trees and turfgrass results in significantly different LST effects, which can be detected at large scales in fractional mixture analysis.

Synegies Between Visible/Near-Infrared Imaging Spectrometry and the Thermal Infrared in an Urban Environment: An Evaluation of the Hyperspectral Infrared Imager (HYSPIRI) Mission

NASA Technical Reports Server (NTRS)

Roberts, Dar A.; Quattrochi, Dale A.; Hulley, Glynn C.; Hook, Simon J.; Green, Robert O.

2012-01-01

A majority of the human population lives in urban areas and as such, the quality of urban environments is becoming increasingly important to the human population. Furthermore, these areas are major sources of environmental contaminants and sinks of energy and materials. Remote sensing provides an improved understanding of urban areas and their impacts by mapping urban extent, urban composition (vegetation and impervious cover fractions), and urban radiation balance through measures of albedo, emissivity and land surface temperature (LST). Recently, the National Research Council (NRC) completed an assessment of remote sensing needs for the next decade (NRC, 2007), proposing several missions suitable for urban studies, including a visible, near-infrared and shortwave infrared (VSWIR) imaging spectrometer and a multispectral thermal infrared (TIR) instrument called the Hyperspectral Infrared Imagery (HyspIRI). In this talk, we introduce the HyspIRI mission, focusing on potential synergies between VSWIR and TIR data in an urban area. We evaluate potential synergies using an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and MODIS-ASTER (MASTER) image pair acquired over Santa Barbara, United States. AVIRIS data were analyzed at their native spatial resolutions (7.5m VSWIR and 15m TIR), and aggregated 60 m spatial resolution similar to HyspIRI. Surface reflectance was calculated using ACORN and a ground reflectance target to remove atmospheric and sensor artifacts. MASTER data were processed to generate estimates of spectral emissivity and LST using Modtran radiative transfer code and the ASTER Temperature Emissivity Separation algorithm. A spectral library of common urban materials, including urban vegetation, roofs and roads was assembled from combined AVIRIS and field-measured reflectance spectra. LST and emissivity were also retrieved from MASTER and reflectance/emissivity spectra for a subset of urban materials were retrieved from co-located MASTER and AVIRIS pixels. Fractions of Impervious, Soil, Green Vegetation (GV) and Non-photosynthetic Vegetation (NPV), were estimated using Multiple Endmember Spectral Mixture Analysis (MESMA) applied to AVIRIS data at 7.5, 15 and 60 m spatial scales. Surface energy parameters, including albedo, vegetation cover fraction, broadband emissivity and LST were also determined for urban and natural land-cover classes in the region. Fractions were validated using 1m digital photography.

Remote Sensing of the Urban Heat Island Effect Across Biomes in the Continental USA

NASA Technical Reports Server (NTRS)

Imhoff, Marc L.; Zhang, Ping; Wolfe, Robert E.; Bounoua, Lahouari

2010-01-01

Impervious surface area (ISA) from the Landsat TM-based NLCD 2001 dataset and land surface temperature (LST) from MODIS averaged over three annual cycles (2003-2005) are used in a spatial analysis to assess the urban heat island (UHI) skin temperature amplitude and its relationship to development intensity, size, and ecological setting for 38 of the most populous cities in the continental United States. Development intensity zones based on %ISA are defined for each urban area emanating outward from the urban core to the nonurban rural areas nearby and used to stratify sampling for land surface temperatures and NDVI. Sampling is further constrained by biome and elevation to insure objective intercomparisons between zones and between cities in different biomes permitting the definition of hierarchically ordered zones that are consistent across urban areas in different ecological setting and across scales. We find that ecological context significantly influences the amplitude of summer daytime UHI (urban-rural temperature difference) the largest (8 C average) observed for cities built in biomes dominated by temperate broadleaf and mixed forest. For all cities combined, ISA is the primary driver for increase in temperature explaining 70% of the total variance in LST. On a yearly average, urban areas are substantially warmer than the non-urban fringe by 2.9 C, except for urban areas in biomes with arid and semiarid climates. The average amplitude of the UHI is remarkably asymmetric with a 4.3 C temperature difference in summer and only 1.3 C in winter. In desert environments, the LST's response to ISA presents an uncharacteristic "U-shaped" horizontal gradient decreasing from the urban core to the outskirts of the city and then increasing again in the suburban to the rural zones. UHI's calculated for these cities point to a possible heat sink effect. These observational results show that the urban heat island amplitude both increases with city size and is seasonally asymmetric for a large number of cities across most biomes. The implications are that for urban areas developed within forested ecosystems the summertime UHI can be quite high relative to the wintertime UHI suggesting that the residential energy consumption required for summer cooling is likely to increase with urban growth within those biomes.

Evaluating the Impacts of Urbanization on Hydrological Processes and Water Resources by Comparing Two Neighboring Basins

NASA Astrophysics Data System (ADS)

Shao, M.; Zhao, G.; Gao, H.

2017-12-01

Texas, the fastest growing state in the US, has seen significant land cover/land use change due to urbanization over the past decades. With most of the region being arid/semi-arid, water issues are unprecedentedly pressing. Among the 15 major river basins, two adjacent river basins located in south-central Texas—the San Antonio River Basin (SARB) and the Guadalupe River Basin (GRB)—form an ideal testbed for evaluating the impacts of urbanization on both hydrological processes and water resources. These two basins are similar in size and in climate pattern, but differ in terms of urbanization progress. In SARB, where the city of San Antonio is located, the impervious area has increased from 0.6% (1929) to 7.8% (2011). In contrast, there is little land cover change in the GRB. With regard to the underground components, both basins intersect with the Edward Aquifer (more than 15% of basin area in both cases). The Edward Aquifer acts as one of the major municipal water supplies for San Antonio, and as the water source for local agricultural uses (and for the surrounding habitat). This aquifer has the characteristic of being highly sensitive to changes in surface water conditions, like the descending trend of the underground water table due to over exploitation. In this study, a distributed hydrologic model—DHSVM (the Distributed Hydrology Soil Vegetation Model)—is used to compare the hydrologic characteristics (and their impacts on water resources) over the two basins. With a 200m spatial resolution, the model is calibrated and validated during the historical period over both basins. The objectives of the comparisons are two-fold: First, the urbanization effects on peak flows are evaluated for selected extreme rainfall events; Second, the Edward Aquifer recharge rate from surface water under flood and/or drought conditions within the two basins is analyzed. Furthermore, future urbanization scenarios are tested to provide information relevant to decision making.

Evaluation of spatio-temporal variability in Land Surface Temperature: A case study of Zonguldak, Turkey.

PubMed

Sekertekin, Aliihsan; Kutoglu, Senol Hakan; Kaya, Sinasi

2016-01-01

The aim of this study is to analyze spatio-temporal variability in Land Surface Temperature (LST) in and around the city of Zonguldak as a result of the growing urbanization and industrialization during the last decade. Three Landsat 5 data and one Landsat 8 data acquired on different dates were exploited in acquiring LST maps utilizing mono-window algorithm. The outcomes obtained from this study indicate that there exists a significant temperature rise in the region for the time period between 1986 and 2015. Some cross sections were selected in order to examine the relationship between the land use and LST changes in more detail. The mean LST difference between 1986 and 2015 in ERDEMIR iron and steel plant (6.8 °C), forestland (3 °C), city and town centers (4.2 °C), municipal rubbish tip (-3.9 °C), coal dump site (12.2 °C), and power plants' region (7 °C) were presented. In addition, the results indicated that the mean LST difference between forestland and city centers was approximately 5 °C, and the difference between forestland and industrial enterprises was almost 8 °C for all years. Spatio-temporal variability in LST in Zonguldak was examined in that study and due to the increase in LST, policy makers and urban planners should consider LST and urban heat island parameters for sustainable development.

Applications of Skylab data to land use and climatological analysis

NASA Technical Reports Server (NTRS)

Alexander, R. H. (Principal Investigator); Lewis, J. E., Jr.; Lins, H. F., Jr.; Jenner, C. B.; Outcalt, S. I.; Pease, R. W.

1976-01-01

The author has identified the following significant results. Skylab study in Central Atlantic Regional Ecological Test Site encompassed two separate but related tasks: (1) evaluation of photographic sensors S190A and B as sources of land use data for planning and managing land resources in major metropolitan regions, and (2) evaluation of the multispectral scanner S192 used in conjunction with associated data and analytical techniques as a data source on urban climates and the surface energy balance. Photographs from the Skylab S190B earth terrain camera were of greatest interest in the land use analysis task; they were of sufficiently high resolution to identify and map many level 2 and 3 land use categories. After being corrected to allow for atmosphere effects, output from thermal and visible bands of the S192 was employed in constructing computer map plots of albedo and surface temperature.

Spatiotemporal variability of hydrologic soil properties and the implications for overland flow and land management in a peri-urban Mediterranean catchment

NASA Astrophysics Data System (ADS)

Ferreira, C. S. S.; Walsh, R. P. D.; Steenhuis, T. S.; Shakesby, R. A.; Nunes, J. P. N.; Coelho, C. O. A.; Ferreira, A. J. D.

2015-06-01

Planning of semi-urban developments is often hindered by a lack of knowledge on how changes in land-use affect catchment hydrological response. The temporal and spatial patterns of overland flow source areas and their connectivity in the landscape, particularly in a seasonal climate, remain comparatively poorly understood. This study investigates seasonal variations in factors influencing runoff response to rainfall in a peri-urban catchment in Portugal characterized by a mosaic of landscape units and a humid Mediterranean climate. Variations in surface soil moisture, hydrophobicity and infiltration capacity were measured in six different landscape units (defined by land-use on either sandstone or limestone) in nine monitoring campaigns at key times over a one-year period. Spatiotemporal patterns in overland flow mechanisms were found. Infiltration-excess overland flow was generated in rainfalls during the dry summer season in woodland on both sandstone and limestone and on agricultural soils on limestone due probably in large part to soil hydrophobicity. In wet periods, saturation overland flow occurred on urban and agricultural soils located in valley bottoms and on shallow soils upslope. Topography, water table rise and soil depth determined the location and extent of saturated areas. Overland flow generated in upslope source areas potentially can infiltrate in other landscape units downslope where infiltration capacity exceeds rainfall intensity. Hydrophilic urban and agricultural-sandstone soils were characterized by increased infiltration capacity during dry periods, while forest soils provided potential sinks for overland flow when hydrophilic in the winter wet season. Identifying the spatial and temporal variability of overland flow sources and sinks is an important step in understanding and modeling flow connectivity and catchment hydrologic response. Such information is important for land managers in order to improve urban planning to minimize flood risk.

Characterization of streamflow, salinity, and selenium loading and land-use change in Montrose Arroyo, western Colorado, from 1992 to 2013

USGS Publications Warehouse

Richards, Rodney J.; Moore, Jennifer L.

2015-01-01

Land use was characterized for 1992, 2002, and 2009 for site MA3. The common land-use change in the MA3 subwatershed was a conversion from previously irrigated agricultural land to urban land use. The MA3 subwatershed had 124 acres of irrigated land use converted to urban land use and 27.1 acres of unirrigated desert converted to urban land use from 1992 to 2009. Consistent with findings in previous land-use change reports, salinity and dissolved-selenium loading at site MA3 showed significant decreases as irrigated land was converted to urban land use.

Green Infrastructure and Watershed-Scale Hydrology in a Mixed Land Cover System

NASA Astrophysics Data System (ADS)

Hoghooghi, N.; Golden, H. E.; Bledsoe, B. P.

2017-12-01

Urbanization results in replacement of pervious areas (e.g., vegetation, topsoil) with impervious surfaces such as roads, roofs, and parking lots, which cause reductions in interception, evapotranspiration, and infiltration, and increases in surface runoff (overland flow) and pollutant loads and concentrations. Research on the effectiveness of different Green Infrastructure (GI), or Low Impact Development (LID), practices to reduce these negative impacts on stream flow and water quality has been mostly focused at the local scale (e.g., plots, small catchments). However, limited research has considered the broader-scale effects of LID, such as how LID practices influence water quantity, nutrient removal, and aquatic ecosystems at watershed scales, particularly in mixed land cover and land use systems. We use the Visualizing Ecosystem Land Management Assessments (VELMA) model to evaluate the effects of different LID practices on daily and long-term watershed-scale hydrology, including infiltration surface runoff. We focus on Shayler Crossing (SHC) watershed, a mixed land cover (61% urban, 24% agriculture, 15% forest) subwatershed of the East Fork Little Miami River watershed, Ohio, United States, with a drainage area of 0.94 km2. The model was calibrated to daily stream flow at the outlet of SHC watershed from 2009 to 2010 and was applied to evaluate diverse distributions (at 25% to 100% implementation levels) and types (e.g., pervious pavement and rain gardens) of LID across the watershed. Results show reduced surface water runoff and higher rates of infiltration concomitant with increasing LID implementation levels; however, this response varies between different LID practices. The highest magnitude response in streamflow at the watershed outlet is evident when a combination of LID practices is applied. The combined scenarios elucidate that the diverse watershed-scale hydrological responses of LID practices depend primarily on the type and extent of the implemented practices. Our work provides a key advancement toward improving current understanding of the effectiveness and efficiencies of LID approaches in mixed land cover watersheds.

The influence of the interactions between anthropogenic activities and multiple ecological factors on land surface temperatures of urban forests

NASA Astrophysics Data System (ADS)

Ren, Y.

2017-12-01

Context Land surface temperatures (LSTs) spatio-temporal distribution pattern of urban forests are influenced by many ecological factors; the identification of interaction between these factors can improve simulations and predictions of spatial patterns of urban cold islands. This quantitative research requires an integrated method that combines multiple sources data with spatial statistical analysis. Objectives The purpose of this study was to clarify urban forest LST influence interaction between anthropogenic activities and multiple ecological factors using cluster analysis of hot and cold spots and Geogdetector model. We introduced the hypothesis that anthropogenic activity interacts with certain ecological factors, and their combination influences urban forests LST. We also assumed that spatio-temporal distributions of urban forest LST should be similar to those of ecological factors and can be represented quantitatively. Methods We used Jinjiang as a representative city in China as a case study. Population density was employed to represent anthropogenic activity. We built up a multi-source data (forest inventory, digital elevation models (DEM), population, and remote sensing imagery) on a unified urban scale to support urban forest LST influence interaction research. Through a combination of spatial statistical analysis results, multi-source spatial data, and Geogdetector model, the interaction mechanisms of urban forest LST were revealed. Results Although different ecological factors have different influences on forest LST, in two periods with different hot spots and cold spots, the patch area and dominant tree species were the main factors contributing to LST clustering in urban forests. The interaction between anthropogenic activity and multiple ecological factors increased LST in urban forest stands, linearly and nonlinearly. Strong interactions between elevation and dominant species were generally observed and were prevalent in either hot or cold spots areas in different years. Conclusions In conclusion, a combination of spatial statistics and GeogDetector models should be effective for quantitatively evaluating interactive relationships among ecological factors, anthropogenic activity and LST.

Urbanization accelerates long-term salinization and alkalinization of fresh water

NASA Astrophysics Data System (ADS)

Kaushal, S.; Duan, S.; Doody, T.; Haq, S.; Smith, R. M.; Newcomer Johnson, T. A.; Delaney Newcomb, K.; Gorman, J. K.; Bowman, N.; Mayer, P. M.; Wood, K. L.; Belt, K.; Stack, W.

2017-12-01

Human dominated land-use increases transport a major ions in streams due to anthropogenic salts and accelerated weathering. We show long-term trends in calcium, magnesium, sodium, alkalinity, and hardness over 50 years in the Baltimore metropolitan region and elsewhere. We also examine how major ion concentrations have increased significantly with impervious surface cover in watersheds across land use. Base cations show strong relationships with acid anions, which illustrates the coupling of major biogeochemical cycles in urban watersheds over time. Longitudinal patterns in major ions can also show increasing trends from headwaters to coastal waters, which suggests coupled biogeochemical cycles over space. We present new results from manipulative experiments and long-term monitoring across different urban regions regarding patterns and processes of salinization and alkalinization. Overall, our work demonstrates that urbanization dramatically increases major ions, ionic strength, and pH over decades from headwaters to coastal waters, which impacts the integrity of aquatic life, infrastructure, drinking water, and coastal ocean alkalinization.

Evaluating the effects of land use on headwater wetland amphibian assemblages in coastal Alabama

USGS Publications Warehouse

Alix, Diane M.; Anderson, Christopher J.; Grand, James B.; Guyer, Craig

2014-01-01

Anthropogenic land use is known to impact aquatic ecosystems in several ways, including increased frequency and intensity of floods, stream channel incision, sedimentation, and loss of microtopography. Amphibians are susceptible to changes in wetland and surrounding habitats. This study evaluated amphibian assemblages of fifteen headwater slope wetlands in coastal Alabama across a gradient of land uses. Amphibians were surveyed on a seasonal basis and land use was delineated within wetland watersheds and within a 200-m buffer surrounding each wetland. Amphibian presence/absence and land use data were used to develop species occupancy models. Both urban and agricultural land use were shown to influence amphibian occurrence. Species richness ranged from five to ten species across sites; however, five species only occurred in wetlands surrounded by forested lands. Many species were detected more frequently on these wetlands compared to wetlands surrounded by urban or mixed land uses. Occupancy models showed Acris gryllus was negatively associated with the amount of agriculture within a buffer around the wetland. Hyla squirella, Lithobates clamitans, and L. sphenocephalus were positively associated with agricultural land within a watershed. Anaxyrus terrestris and the non-native Eleutherodactylus planirostris were positively associated with the amount of impervious surface area within the wetland buffer.

Spatio-temporal dynamics of sediment sources in a peri-urban Mediterranean catchment

NASA Astrophysics Data System (ADS)

Ferreira, Carla; Walsh, Rory; Blake, William; Kikuchi, Ryunosuke; Ferreira, António

2017-04-01

Sediment fluxes driven by hydrological processes lead to natural soil losses, but human activities, such as urbanization, influence hydrology and promote erosion, altering the landscape and sediment fluxes. In peri-urban areas, comprising a mixture of semi-natural and man-made land-uses, understanding sediment fluxes is still a research challenge. This study investigates spatial and temporal dynamics of fluvial sediments in a rapidly urbanizing catchment. Specific objectives are to understand the main sources of sediments relating to different types of urban land disturbance, and their variability driven by (i) weather, season and land-use changes through time, and (ii) sediment particle size. The study was carried out Ribeira dos Covões, a peri-urban catchment (6.2km2) in central Portugal. The climate is humid Mediterranean, with mean annual temperature and rainfall of 15˚ C and 892 mm, respectively. The geology comprises sandstone (56%), limestone (41%) and alluvial deposits (3%). The catchment has an average slope of 9˚ , but includes steep slopes of up to 46˚ . The land-use is a complex mosaic of woodland (56%), urban (40%) and agricultural (4%) land parcels, resulting from urbanization occurring progressively since 1973. Urbanization since 2010 has mainly comprised the building of a major road, covering 1% of the catchment area, and the ongoing construction of an enterprise park, occupying 5% of the catchment. This study uses a multi-proxy sediment fingerprinting approach, based on X-Ray Fluorescence (XRF) analyses to characterize the elemental geochemistry of sediments collected within the stream network after three storm events in 2012 and 2015. A range of statistical techniques, including hierarchical cluster analysis, was used to identify discriminant sediment properties and similarities between fine bed-sediment samples of tributaries and downstream sites. Quantification of sediment supply from upstream sub-catchments was undertaken using a Bayesian unmixing model. Geochemical signatures of sub-catchment sediment varied significantly with lithology and type of urban influence, but a tendency for limestone sub-catchments to be more urbanized made it difficult to isolate the influence of each factor. Nevertheless, differences in sub-catchment geochemistry between the survey dates indicate significant changes through time in both the relative importance and character of urban impacts. In 2012 the sandstone sub-catchment provided 88%, 92% and 93% of the <63μm, 63μm-125μm and 125μm-2000μm sediment, respectively, with most sediment deriving from the enterprise park site undergoing deforestation and construction. Most of the remaining sediment derived from the construction of the major road in the limestone sub-catchment. In 2015, however, sediment losses within the catchment appear to have been significantly reduced by planned and accidental retention basins below the enterprise park and major road construction sites, respectively. Nevertheless, the landscape disturbance provided by these constructional sites was of much greater importance than sediment mobilization in urban areas with paved roads and other impervious surfaces. The greatest heavy metal concentrations, however, were recorded in sediments deriving from road runoff. Despite the positive impact of retention basins in reducing sediment delivery from human disturbed areas, sediment connectivity could be reduced further by dispersing and filtering upslope runoff from urban surfaces more systematically into woodland sink areas.

Estimating changes in urban land and urban population using refined areal interpolation techniques

NASA Astrophysics Data System (ADS)

Zoraghein, Hamidreza; Leyk, Stefan

2018-05-01

The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead, it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.

Changing Urbania: Estimating Changes in Urban Land and Urban Population Using Refined Areal Interpolation Techniques

NASA Astrophysics Data System (ADS)

Zoraghein, H.; Leyk, S.; Balk, D.

2017-12-01

The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. The U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.

Gross Primary Productivity and Vegetation Light Use Efficiency of a Large Metropolitan Region based on CO2 Flux Measurements and WorldView-2 Satellite Imagery

NASA Astrophysics Data System (ADS)

Miller, D. L.; Roberts, D. A.; Clarke, K. C.; Peters, E. B.; Menzer, O.; Lin, Y.; McFadden, J. P.

2017-12-01

Gross primary productivity (GPP) is commonly estimated with remote sensing techniques over large regions of Earth; however, urban areas are typically excluded due to a lack of light use efficiency (LUE) parameters specific to urban vegetation and challenges stemming from the spatial heterogeneity of urban land cover. In this study, we estimated GPP during the middle of the growing season, both within and among vegetation and land use types, in the Minneapolis-Saint Paul, Minnesota metropolitan region (52.1% vegetation cover). We derived LUE parameters for specific urban vegetation types using estimates of GPP from eddy covariance and tree sap flow-based CO2 flux observations and fraction of absorbed photosynthetically active radiation derived from 2-m resolution WorldView-2 satellite imagery. We produced a pixel-based hierarchical land cover classification of built-up and vegetated urban land cover classes distinguishing deciduous broadleaf trees, evergreen needleleaf trees, turf grass, and golf course grass from impervious and soil surfaces. The overall classification accuracy was 80% (kappa = 0.73). The mapped GPP estimates were within 12% of estimates from independent tall tower eddy covariance measurements. Mean GPP estimates ( ± standard deviation; g C m-2 day-1) for the entire study area from highest to lowest were: golf course grass (11.77 ± 1.20), turf grass (6.05 ± 1.07), evergreen needleleaf trees (5.81 ± 0.52), and deciduous broadleaf trees (2.52 ± 0.25). Turf grass GPP had a larger coefficient of variation (0.18) than the other vegetation classes ( 0.10). Mean land use GPP for the full study area varied as a function of percent vegetation cover. Urban GPP in general, both including and excluding non-vegetated areas, was less than half that of literature estimates for nearby natural forests and grasslands.

Fraser River watershed, Colorado : assessment of available water-quantity and water-quality data through water year 1997

USGS Publications Warehouse

Apodaca, Lori Estelle; Bails, Jeffrey B.

1999-01-01

The water-quantity and water-quality data for the Fraser River watershed through water year 1997 were compiled for ground-water and surface-water sites. In order to assess the water-quality data, the data were related to land use/land cover in the watershed. Data from 81 water-quantity and water-quality sites, which consisted of 9 ground-water sites and 72 surface-water sites, were available for analysis. However, the data were limited and frequently contained only one or two water-quality analyses per site.The Fraser River flows about 28 miles from its headwaters at the Continental Divide to the confluence with the Colorado River. Ground-water resources in the watershed are used for residential and municipal drinking-water supplies. Surface water is available for use, but water diversions in the upper parts of the watershed reduce the flow in the river. Land use/land cover in the watershed is predominantly forested land, but increasing urban development has the potential to affect the quantity and quality of the water resources.Analysis of the limited ground-water data in the watershed indicates that changes in the land use/land cover affect the shallow ground-water quality. Water-quality data from eight shallow monitoring wells in the alluvial aquifer show that iron and manganese concentrations exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level. Radon concentrations from these monitoring wells exceeded the U.S. Environmental Protection Agency proposed maximum contaminant level. The proposed radon contaminant level is currently being revised. The presence of volatile organic compounds at two monitoring wells in the watershed indicates that land use affects the shallow ground water. In addition, bacteria detected in three samples are at concentrations that would be a concern for public health if the water was to be used as a drinking supply. Methylene blue active substances were detected in the ground water at some sites and are a possible indication of contamination from wastewater. Age of the alluvial ground water ranged from 10 to 30 years; therefore, results of land-management practices to improve water quality may not be apparent for many years.Surface-water-quality data for the Fraser River watershed are sparse. The surface-water-quality data show that elevated concentrations of selected constituents generally are related to specific land uses in the watershed. For one sample (about 2 percent; 1 of 53), dissolved manganese concentration exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level. Two samples from two surface-water sites in the watershed exceeded the un-ionized ammonia chronic criterion. Spatial distribution of nutrient species (ammonia, nitrite, nitrate, and total phosphorus) shows that elevated concentrations occur primarily downstream from urban areas. Sites with five or more years of record were analyzed for temporal trends in concentration of nutrient species. Downward trends were identified for ammonia and nitrite for three surface-water sites. For nitrate, no trends were observed at two sites and a downward trend was observed at one site. Total phosphorus showed no trend for the site near the mouth of the Fraser River. Downward trends in the nutrient species may reflect changes in the wastewater-treatment facilities in the watershed. Bacteria sampling completed in the watershed indicates that more bacteria are present in the water near urban settings.The limited ground-water and surface-water data for the Fraser River watershed provide a general assessment of the quantity and quality of these resources. Concentrations of most water-quality constituents generally are less than ground- and surface-water-quality standards, but the presence of bacteria, some volatile organic compounds, methylene blue active substances, and increased nutrients in the water may indicate that land use is affecting the water quality..

The use of NOAA AVHRR data for assessment of the urban heat sland effect

USGS Publications Warehouse

Gallo, K.P.; McNab, A. L.; Karl, Thomas R.; Brown, Jesslyn F.; Hood, J. J.; Tarpley, J.D.

1993-01-01

A vegetation index and a radiative surface temperature were derived from satellite data acquired at approximately 1330 LST for each of 37 cities and for their respective nearby rural regions from 28 June through 8 August 1991. Urban–rural differences for the vegetation index and the surface temperatures were computed and then compared to observed urban–rural differences in minimum air temperatures. The purpose of these comparisons was to evaluate the use of satellite data to assess the influence of the urban environment on observed minimum air temperatures (the urban heat island effect). The temporal consistency of the data, from daily data to weekly, biweekly, and monthly intervals, was also evaluated. The satellite-derived normalized difference (ND) vegetation-index data, sampled over urban and rural regions composed of a variety of land surface environments, were linearly related to the difference in observed urban and rural minimum temperatures. The relationship between the ND index and observed differences in minimum temperature was improved when analyses were restricted by elevation differences between the sample locations and when biweekly or monthly intervals were utilized. The difference in the ND index between urban and rural regions appears to be an indicator of the difference in surface properties (evaporation and heat storage capacity) between the two environments that are responsible for differences in urban and rural minimum temperatures. The urban and rural differences in the ND index explain a greater amount of the variation observed in minimum temperature differences than past analyses that utilized urban population data. The use of satellite data may contribute to a globally consistent method for analysis of urban heat island bias.

Expansion of oil palm and other cash crops causes an increase of the land surface temperature in the Jambi province in Indonesia

NASA Astrophysics Data System (ADS)

Sabajo, Clifton R.; le Maire, Guerric; June, Tania; Meijide, Ana; Roupsard, Olivier; Knohl, Alexander

2017-10-01

Indonesia is currently one of the regions with the highest transformation rate of land surface worldwide related to the expansion of oil palm plantations and other cash crops replacing forests on large scales. Land cover changes, which modify land surface properties, have a direct effect on the land surface temperature (LST), a key driver for many ecological functions. Despite the large historic land transformation in Indonesia toward oil palm and other cash crops and governmental plans for future expansion, this is the first study so far to quantify the impacts of land transformation on the LST in Indonesia. We analyze LST from the thermal band of a Landsat image and produce a high-resolution surface temperature map (30 m) for the lowlands of the Jambi province in Sumatra (Indonesia), a region which suffered large land transformation towards oil palm and other cash crops over the past decades. The comparison of LST, albedo, normalized differenced vegetation index (NDVI) and evapotranspiration (ET) between seven different land cover types (forest, urban areas, clear-cut land, young and mature oil palm plantations, acacia and rubber plantations) shows that forests have lower surface temperatures than the other land cover types, indicating a local warming effect after forest conversion. LST differences were up to 10.1 ± 2.6 °C (mean ± SD) between forest and clear-cut land. The differences in surface temperatures are explained by an evaporative cooling effect, which offsets the albedo warming effect. Our analysis of the LST trend of the past 16 years based on MODIS data shows that the average daytime surface temperature in the Jambi province increased by 1.05 °C, which followed the trend of observed land cover changes and exceeded the effects of climate warming. This study provides evidence that the expansion of oil palm plantations and other cash crops leads to changes in biophysical variables, warming the land surface and thus enhancing the increase of the air temperature because of climate change.

Urban and regional land use analysis: CARETS and Census Cities experiment package. [mapping land use climatology from MSS imagery

NASA Technical Reports Server (NTRS)

Alexander, R. H. (Principal Investigator)

1973-01-01

The author has identified the following significant results. The arrival of the so-called energy crisis makes the portion of this experiment dealing with land use climatology of more immediate significance than before, since in addition to helping to understand the processes of climatic change associated with urbanization, the knowledge obtained may be useful in assigning an energy balance impact factor to proposed changes in land use in and around cities. Thermal maps derived from S-192 data are to be used as a measure of the energy being radiated into space from the mosaic of different surfaces in and around the city. While presenting excellent spatial sampling potential for a metropolitan area tests site, the Skylab data permit a very poor temporal sampling opportunity, owing to the large number of factors beyond the investigator's control that determine when data will be taken over a given test site. The strategy is to augment the thermal maps derived from S-192 with a modeling technique which enables the simulation of a number of components of the surface energy balance, calculated at regular time intervals throughout the day or year. Preliminary tests on the performance of the model are still underway, using airborne MSS data from NASA aircraft flights. Results look extremely promising.

Global assessment of rural-urban interface in Portugal related to land cover changes

NASA Astrophysics Data System (ADS)

Tonini, Marj; Parente, Joana; Pereira, Mário G.

2018-06-01

The rural-urban interface (RUI), known as the area where structures and other human developments meet or intermingle with wildland and rural area, is at present a central focus of wildfire policy and its mapping is crucial for wildfire management. In the Mediterranean Basin, humans cause the vast majority of fires and fire risk is particularly high in the proximity of infrastructure and of rural/wildland areas. RUI's extension changes under the pressure of environmental and anthropogenic factors, such as urban growth, fragmentation of rural areas, deforestation and, more in general, land use/land cover change (LULCC). As with other Mediterranean countries, Portugal has experienced significant LULCC in the last decades in response to migration, rural abandonment, ageing of population and trends associated with the high socioeconomic development. In the present study, we analyzed the LULCC occurring in this country in the 1990-2012 period with the main objective of investigating how these changes affected RUI's evolution. Moreover, we performed a qualitative and quantitative characterization of burnt areas within the RUI in relation to the observed changes. Obtained results disclose important LULCC and reveal their spatial distribution, which is far from uniform within the territory. A significant increase in artificial surfaces was registered near the main metropolitan communities of the northwest, littoral-central and southern regions, whilst the abandonment of agricultural land near the inland urban areas led to an increase in uncultivated semi-natural and forest areas. Within agricultural areas, heterogeneous patches suffered the greatest changes and were the main contributors to the increase in urban areas; moreover, this land cover class, together with forests, was highly affected by wildfires in terms of burnt area. Finally, from this analysis and during the investigated period, it appears that RUI increased in Portugal by more than two-thirds, while the total burnt area decreased by one-third; nevertheless, burnt area within RUI doubled, which emphasizes the significance of RUI monitoring for land and fire managers.

Projecting the land cover change and its environmental impacts in the Cedar River Basin in the Midwestern United States

USGS Publications Warehouse

Wu, Yiping; Liu, Shuguang; Sohl, Terry L.; Young, Claudia

2013-01-01

The physical surface of the Earth is in constant change due to climate forcing and human activities. In the Midwestern United States, urban area, farmland, and dedicated energy crop (e.g., switchgrass) cultivation are predicted to expand in the coming decades, which will lead to changes in hydrological processes. This study is designed to (1) project the land use and land cover (LULC) by mid-century using the FORecasting SCEnarios of future land-use (FORE-SCE) model under the A1B greenhouse gas emission scenario (future condition) and (2) assess its potential impacts on the water cycle and water quality against the 2001 baseline condition in the Cedar River Basin using the physically based soil and water assessment tool (SWAT). We compared the baseline LULC (National Land Cover data 2001) and 2050 projection, indicating substantial expansions of urban area and pastureland (including the cultivation of bioenergy crops) and a decrease in rangeland. We then used the above two LULC maps as the input data to drive the SWAT model, keeping other input data (e.g., climate) unchanged to isolate the LULC change impacts. The modeling results indicate that quick-response surface runoff would increase significantly (about 10.5%) due to the projected urban expansion (i.e., increase in impervious areas), and the baseflow would decrease substantially (about 7.3%) because of the reduced infiltration. Although the net effect may cause an increase in water yield, the increased variability may impede its use for public supply. Additionally, the cultivation of bioenergy crops such as switchgrass in the newly added pasture lands may further reduce the soil water content and lead to an increase in nitrogen loading (about 2.5% increase) due to intensified fertilizer application. These study results will be informative to decision makers for sustainable water resource management when facing LULC change and an increasing demand for biofuel production in this area.

Water-quality observations of the San Antonio segment of the Edwards aquifer, Texas, with an emphasis on processes influencing nutrient and pesticide geochemistry and factors affecting aquifer vulnerability, 2010–16

USGS Publications Warehouse

Opsahl, Stephen P.; Musgrove, MaryLynn; Mahler, Barbara J.; Lambert, Rebecca B.

2018-06-07

As questions regarding the influence of increasing urbanization on water quality in the Edwards aquifer are raised, a better understanding of the sources, fate, and transport of compounds of concern in the aquifer—in particular, nutrients and pesticides—is needed to improve water management decision-making capabilities. The U.S. Geological Survey, in cooperation with the San Antonio Water System, performed a study from 2010 to 2016 to better understand how water quality changes under a range of hydrologic conditions and in contrasting land-cover settings (rural and urban) in the Edwards aquifer. The study design included continuous hydrologic monitoring, continuous water-quality monitoring, and discrete sample collection for a detailed characterization of water quality at a network of sites throughout the aquifer system. The sites were selected to encompass a “source-to-sink” (that is, from aquifer recharge to aquifer discharge) approach. Network sites were selected to characterize rainfall, recharging surface water, and groundwater; groundwater sites included wells in the unconfined part of the aquifer (unconfined wells) and in the confined part of the aquifer (confined wells) and a major discharging spring. Storm-related samples—including rainfall samples, stormwater-runoff (surface-water) samples, and groundwater samples—were collected to characterize the aquifer response to recharge.Elevated nitrate concentrations relative to national background values and the widespread detection of pesticides indicate that the Edwards aquifer is vulnerable to contamination and that vulnerability is affected by factors such as land cover, aquifer hydrogeology, and changes in hydrologic conditions. Greater vulnerability of groundwater in urban areas relative to rural areas was evident from results for urban groundwater sites, which generally had higher nitrate concentrations, elevated δ15N-nitrate values, a greater diversity of pesticides, and higher pesticide concentrations. The continuum of water quality from unconfined rural groundwater sites (least affected by anthropogenic contamination) to unconfined urban groundwater sites (most affected by anthropogenic contamination) demonstrates enhanced vulnerability of urban versus rural land cover. Differences in contaminant occurrences and concentration among unconfined urban wells indicate that the urban parts of the aquifer are not uniformly vulnerable, but rather are affected by spatial differences in the sources of nutrients and pesticides. In urban areas, the shallow, unconfined groundwater sites showed greater temporal variability in both nutrient and pesticide concentrations, as well as a greater degree of contamination, than did deeper, confined groundwater sites. In comparison to that of the shallow, unconfined groundwater sites, the water quality of the deeper, confined groundwater sites was relatively invariant during this multiyear study. Although aquifer hydrogeology is an important factor related to aquifer vulnerability, land cover likely has a greater influence on pesticide contamination of groundwater. Temporal variability in hydrologic conditions for the Edwards aquifer is apparent in data for surface water as a source of groundwater recharge, water-level altitude in wells, spring discharge, and groundwater quality. This temporal variability affects recharge sources, recharge amounts, groundwater traveltimes, flow routing, water-rock interaction processes, dilution, mixing, and, in turn, water quality. Relations of land cover, aquifer hydrogeology, and changing hydrologic conditions to water quality are complex but provide insight into the vulnerability of Edwards aquifer groundwater—a vital drinking-water resource.

Generation of a U.S. national urban land use product

USGS Publications Warehouse

Falcone, James A.; Homer, Collin G.

2012-01-01

Characterization of urban land uses is essential for many applications. However, differentiating among thematically-detailed urban land uses (residential, commercial, industrial, institutional, recreational, etc.) over broad areas is challenging, in part because image-based solutions are not ideal for establishing the contextual basis for identifying economic function and use. At present no current United States national-scale mapping exists for urban land uses similar to the classical Anderson Level II classification. This paper describes a product that maps urban land uses, and is linked to and corresponds with the National Land Cover Database (NLCD) 2006. In this product, NLCD urban pixels, in addition to their current imperviousness intensity classification, are assigned one of nine urban use classes based on information drawn from multiple data sources. These sources include detailed infrastructure information, population characteristics, and historical land use. The result is a method for creating a 30 m national-scale grid providing thematically-detailed urban land use information which complements the NLCD. Initial results for 10 major metropolitan areas are provided as an on-line link. Accuracy assessment of initial products yielded an overall accuracy of 81.6 percent.

MODIS-based spatiotemporal patterns of soil moisture and evapotranspiration interactions in Tampa Bay urban watershed

NASA Astrophysics Data System (ADS)

Chang, Ni-Bin; Xuan, Zhemin; Wimberly, Brent

2011-09-01

Soil moisture and evapotranspiration (ET) is affected by both water and energy balances in the soilvegetation- atmosphere system, it involves many complex processes in the nexus of water and thermal cycles at the surface of the Earth. These impacts may affect the recharge of the upper Floridian aquifer. The advent of urban hydrology and remote sensing technologies opens new and innovative means to undertake eventbased assessment of ecohydrological effects in urban regions. For assessing these landfalls, the multispectral Moderate Resolution Imaging Spectroradiometer (MODIS) remote sensing images can be used for the estimation of such soil moisture change in connection with two other MODIS products - Enhanced Vegetation Index (EVI), Land Surface Temperature (LST). Supervised classification for soil moisture retrieval was performed for Tampa Bay area on the 2 kmx2km grid with MODIS images. Machine learning with genetic programming model for soil moisture estimation shows advances in image processing, feature extraction, and change detection of soil moisture. ET data that were derived by Geostationary Operational Environmental Satellite (GOES) data and hydrologic models can be retrieved from the USGS web site directly. Overall, the derived soil moisture in comparison with ET time series changes on a seasonal basis shows that spatial and temporal variations of soil moisture and ET that are confined within a defined region for each type of surfaces, showing clustered patterns and featuring space scatter plot in association with the land use and cover map. These concomitant soil moisture patterns and ET fluctuations vary among patches, plant species, and, especially, location on the urban gradient. Time series plots of LST in association with ET, soil moisture and EVI reveals unique ecohydrological trends. Such ecohydrological assessment can be applied for supporting the urban landscape management in hurricane-stricken regions.