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Sample records for defining climate zones

  1. Genetic delineation of local provenance defines seed collection zones along a climate gradient

    PubMed Central

    Hufford, Kristina M.; Veneklaas, Erik J.; Lambers, Hans; Krauss, Siegfried L.

    2016-01-01

    Efforts to re-establish native plant species should consider intraspecific variation if we are to restore genetic diversity and evolutionary potential. Data describing spatial genetic structure and the scale of adaptive differentiation are needed for restoration seed sourcing. Genetically defined provenance zones provide species-specific guidelines for the distance within which seed transfer likely maintains levels of genetic diversity and conserves locally adapted traits. While a growing number of studies incorporate genetic marker data in delineation of local provenance, they often fail to distinguish the impacts of neutral and non-neutral variation. We analysed population genetic structure for 134 amplified fragment length polymorphism (AFLP) markers in Stylidium hispidum (Stylidiaceae) along a north–south transect of the species' range with the goal to estimate the distance at which significant genetic differences occur among source and recipient populations in restoration. In addition, we tested AFLP markers for signatures of selection, and examined the relationship of neutral and putatively selected markers with climate variables. Estimates of population genetic structure revealed significant levels of differentiation (ΦPT = 0.23) and suggested a global provenance distance of 45 km for pairwise comparisons of 16 populations. Of the 134 markers, 13 exhibited evidence of diversifying selection (ΦPT = 0.52). Using data for precipitation and thermal gradients, we compared genetic, geographic and environmental distance for subsets of neutral and selected markers. Strong isolation by distance was detected in all cases, but positive correlations with climate variables were present only for markers with signatures of selection. We address findings in light of defining local provenance in ecological restoration. PMID:26755503

  2. Vegetation zones in changing climate

    NASA Astrophysics Data System (ADS)

    Belda, Michal; Holtanova, Eva; Halenka, Tomas; Kalvova, Jaroslava

    2017-04-01

    of individual types, in the continental scale some shifts of boundaries between the selected types can be studied as well providing the information on climate change signal. The shift of the boundary between the boreal zone and continental temperate zone to the north is clearly seen in most simulations as well as eastern move of the boundary of the maritime and continental type of temperate zone. However, there can be quite clear problem with model biases in climate types association. When analysing climate types in Europe and their shifts under climate change using Köppen-Trewartha classification (KTC), for the temperate climate type there are subtypes defined following the continentality patterns, and we can see their generally meridionally located divide across Europe shifted to the east. There is a question whether this is realistic or rather due to the simplistic condition in KTC following the winter minimum temperature, while other continentality indices consider rather the amplitude of temperature during the year. This leads us to connect our analysis of climate change effects using climate classification to the more detailed analysis of continentality patterns development in Europe to provide better insight on the climate regimes and to verify the continentality conditions, their definitions and climate change effects on them. The comparison of several selected continentality indices is shown.

  3. Climate change and dead zones.

    PubMed

    Altieri, Andrew H; Gedan, Keryn B

    2015-04-01

    Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones. © 2014 John Wiley & Sons Ltd.

  4. Hybrid Zones: Windows on Climate Change

    PubMed Central

    Larson, Erica L.; Harrison, Richard G.

    2016-01-01

    Defining the impacts of anthropogenic climate change on biodiversity and species distributions is currently a high priority. Niche models focus primarily on predicted changes in abiotic factors; however, species interactions and adaptive evolution will impact the ability of species to persist in the face of changing climate. Our review focuses on the use of hybrid zones to monitor species' responses to contemporary climate change. Monitoring hybrid zones provides insight into how range boundaries shift in response to climate change by illuminating the combined effects of species interactions and physiological sensitivity. At the same time, the semi-permeable nature of species boundaries allows us to document adaptive introgression of alleles associated with response to climate change. PMID:25982153

  5. Temporal change of climate zones in China in the context of climate warming

    NASA Astrophysics Data System (ADS)

    Zhang, Xianliang; Yan, Xiaodong

    2014-01-01

    In China, ten climate types were classified using the K-means cluster analysis based on monthly temperature and precipitation data from 753 national meteorological stations for the period 1966-2005. However, 11 mountain climate stations, which are located in southeast China, were classified as one type due to their distinct climate characteristic that differentiated them from other stations. This type could not represent the climate characteristic of this region because all climate stations in this type were located at high-elevation mountains. Thus, it was eliminated when defining climate zones based on climate types. Therefore, nine climate zones were defined in China. Moreover, the temporal change of climate zones was detected in 20-year intervals (1966-1985 and 1986-2005). Although 48 stations changed their climate zones between these two periods, the whole pattern of all climate zones remained stable in these two periods. However, the boundaries between some climate zones changed slightly due to inconsistent variation of regional temperature and precipitation. The most obvious change was the eastern movement of the boundary between an arid temperate zone and a sub-humid temperate zone. There was also a northern shift of the boundary between a tropic zone and a southern subtropic zone. All these changes were probably connected with the climate change in recent 40 years.

  6. Defining Steamside Management Zones or Riparian Buffers

    Treesearch

    Thomas M. Williams; Donald J. Lipscomb; Christopher J. Post

    2004-01-01

    Forestry Best Management Practices (BMPs) have been highly successful in protecting water quality throughout the Southeast. Numerous studies have found them to be effective in protecting water quality. Despite being mostly voluntary, compliance is generally about 90 percent across the region. Streamside Management Zones (SMZs) or riparian buffers are specified for...

  7. Climate zones on Pluto and Charon

    NASA Astrophysics Data System (ADS)

    Binzel, Richard P.; Earle, Alissa M.; Buie, Marc W.; Young, Leslie A.; Stern, S. Alan; Olkin, Cathy B.; Ennico, Kimberly; Moore, Jeffrey M.; Grundy, Will; Weaver, Harold A.; Lisse, Carey M.; Lauer, Tod R.; New Horizons Geology; Geophysics Imaging Team

    2017-05-01

    We give an explanatory description of the unusual ;climate zones; on Pluto that arise from its high obliquity (mean 115°) and high amplitude (±12°) of obliquity oscillation over a 2.8 million year period. The zones we describe have astronomically defined boundaries and do not incorporate atmospheric circulation. For such a high mean obliquity, the lines of tropics (greatest latitudes where the Sun can be overhead) cycle closer to each pole than does each arctic circle, which in turn cycle nearly to the equator. As a consequence in an astronomical context, Pluto is more predominantly ;tropical; than ;arctic.; Up to 97% of Pluto's surface area can experience overhead Sun when the obliquity cycle is at its minimum of 103°. At this same obliquity phase (most recently occurring 0.8 Myr ago), 78% of Pluto's surface experienced prolonged intervals without sunlight or ;arctic winter; (and corresponding ;arctic summer;). The intersection of these climate zones implies that a very broad range of Pluto's latitudes (spanning 13-77° in each hemisphere; 75% of the total surface area) are both tropical and arctic. While some possible correlations to these climate zones are suggested by comparison with published maps of Pluto and Charon yielded by the New Horizons mission, in this work we present a non-physical descriptive analysis only. For example, the planet-wide dark equatorial band presented by Stern et al. (2015; Science, 350, 292-299) corresponds to Pluto's permanent ;diurnal zone.; In this zone spanning latitudes within ±13° of the equator, day-night cycles occur each Pluto rotation (6.4 days) such that neither ;arctic winter; nor ;arctic summer; has been experienced in this zone for at least 20 million years. The stability of this and other climate zones may extend over several Gyr. Temperature modeling shows that the continuity of diurnal cycles in this region may be the key factor enabling a long-term stability for the high albedo contrast between Tombaugh Regio

  8. Vegetation zones shift in changing climate

    NASA Astrophysics Data System (ADS)

    Belda, Michal; Halenka, Tomas; Kalvova, Jaroslava; Holtanova, Eva

    2016-04-01

    The analysis of climate patterns can be performed for each climate variable separately or the data can be aggregated using e.g. some kind of climate classification. These classifications usually correspond to vegetation distribution in the sense that each climate type is dominated by one vegetation zone or eco-region. In case of the Köppen-Trewartha classification it is integrated assessment of temperature and precipitation together with their annual cycle as well. This way climate classifications also represent a convenient tool for the assessment and validation of climate models and for the analysis of simulated future climate changes. The Köppen-Trewartha classification is used on full CMIP5 family of more than 40 GCM simulations and CRU dataset for comparison. This evaluation provides insight on the GCM performance and errors for simulations of the 20th century climate. Common regions are identified, such as Australia or Amazonia, where many state-of-the-art models perform inadequately. Furthermore, the analysis of the CMIP5 ensemble for RCP 4.5 and 8.5 is performed to assess the climate change for future. There are significant changes for some types in most models e.g. increase of savanna and decrease of tundra for the future climate. For some types significant shifts in latitude can be seen when studying their geographical location in selected continental areas, e.g. toward higher latitudes for boreal climate. For Europe, EuroCORDEX results for both 0.11 and 0.44 degree resolution are validated using Köppen-Trewartha types in comparison to E-OBS based classification. ERA-Interim driven simulations are compared to both present conditions of CMIP5 models as well as their downscaling by EuroCORDEX RCMs. Finally, the climate change signal assessment is provided using the individual climate types. In addition to the changes assessed similarly as for GCMs analysis in terms of the area of individual types, in the continental scale some shifts of boundaries

  9. A first approach to calculate BIOCLIM variables and climate zones for Antarctica

    NASA Astrophysics Data System (ADS)

    Wagner, Monika; Trutschnig, Wolfgang; Bathke, Arne C.; Ruprecht, Ulrike

    2017-02-01

    For testing the hypothesis that macroclimatological factors determine the occurrence, biodiversity, and species specificity of both symbiotic partners of Antarctic lecideoid lichens, we present a first approach for the computation of the full set of 19 BIOCLIM variables, as available at http://www.worldclim.org/ for all regions of the world with exception of Antarctica. Annual mean temperature (Bio 1) and annual precipitation (Bio 12) were chosen to define climate zones of the Antarctic continent and adjacent islands as required for ecological niche modeling (ENM). The zones are based on data for the years 2009-2015 which was obtained from the Antarctic Mesoscale Prediction System (AMPS) database of the Ohio State University. For both temperature and precipitation, two separate zonings were specified; temperature values were divided into 12 zones (named 1 to 12) and precipitation values into five (named A to E). By combining these two partitions, we defined climate zonings where each geographical point can be uniquely assigned to exactly one zone, which allows an immediate explicit interpretation. The soundness of the newly calculated climate zones was tested by comparison with already published data, which used only three zones defined on climate information from the literature. The newly defined climate zones result in a more precise assignment of species distribution to the single habitats. This study provides the basis for a more detailed continental-wide ENM using a comprehensive dataset of lichen specimens which are located within 21 different climate regions.

  10. Challenges in Defining Seismogenic Zone Using Geodetic and Structural Observations

    NASA Astrophysics Data System (ADS)

    Wang, K.; Hyndman, R. D.

    2004-12-01

    The coseismic fault slip area in recent subduction earthquakes can be determined from seismological, tsumani, and geodetic observations. The coseismic rupture appears to be limited generally by a temperature around 125° C at the updip end and a temperature around 350° C or the intersection of the plate interface with the forearc Moho at the downdip end, with significant along-strike variations. Defining the seismogenic zone from interseismic deformation is much more challenging, because of the fewer available observation methods and the poorly understood earthquake cycle deformation process. It is reasonable to expect the rupture zone to be locked in the interseismic period, but the updip and downdip limits of mechanical locking do not usually have clear simple geodetic signatures. Fault motion outside the locked zone is not simply determined by frictional properties and fault stress. Surface deformation changes through the earthquake cycle due to both transient fault slip and viscoelastic stress relaxation. If an elastic dislocation model is used to explain decade- and century-scale viscoelastic interseismic deformation, a more gradual downdip tapering of locking is required to fit geodetic observations long after the most recent earthquake. Rate- and state-dependent friction and nonlinear mantle rock rheology are both important candidates in explaining transient afterslip of duration of days to a few years downdip of coseismic rupture, although their distinction is obscured by strain localization in nonlinear deformation. Newtonian rheology is arguably applicable a few fault dimensions from the rupture zone and several years after the earthquake. Cascadia and Nankai episodic "silent" slips indicate that the forearc material at 30-40 km depths is able to accumulate and release elastic strain energy. It has been proposed that such slip may be shear deformation of a band of km's thickness above the subducting slab (and that the shear band terminates seismogenic

  11. Drought analysis according to shifting of climate zones to arid climate zone over Asia monsoon region

    NASA Astrophysics Data System (ADS)

    Son, Kyung-Hwan; Bae, Deg-Hyo

    2015-10-01

    When a humid region is affected by arid climate, significant changes in drought characteristics occur due to imbalance of water budget. In this study, change in drought characteristics according to shift of different climates i.e. tropical, warm temperate, cold and polar to Arid Climate (SAC) was analyzed over the Asia monsoon region. Climate zones and the SAC regions were identified by applying the Köppen climate classification on hydro-meteorological data for the period of 1963-2006. The analysis of hydro-meteorological parameters revealed that the annual precipitation and runoff in the SAC regions appeared to decrease about 12.1% and 27.3%, respectively, while annual average temperature increased about 0.5 °C. Standardized runoff index (SRI) was calculated using model-driven runoff data. The trend and change point analyses of SRI were performed to evaluate the changes in drought characteristics (frequency, duration, severity) before and after shifting of the different climates to arid climate. The results revealed strong decreasing trend of SRI and hence intensified drought conditions for the SAC regions. A change point year of drought occurred about 3-5 years earlier than the shifting time of the SAC region. Frequency and duration of droughts in the SAC regions were observed to increase about 9.2 and 1.5 months, respectively, and drought severity index intensified to about -0.15. It can be concluded that analysis of shifting to arid climate zones should be considered together with changes in drought characteristics, because the drought characteristics and changing arid climate zones are closely related to each other.

  12. Downscaling NASA Climatological Data to Produce Detailed Climate Zone Maps

    NASA Technical Reports Server (NTRS)

    Chandler, William S.; Hoell, James M.; Westberg, David J.; Whitlock, Charles H.; Zhang, Taiping; Stackhouse, P. W.

    2011-01-01

    The design of energy efficient sustainable buildings is heavily dependent on accurate long-term and near real-time local weather data. To varying degrees the current meteorological networks over the globe have been used to provide these data albeit often from sites far removed from the desired location. The national need is for access to weather and solar resource data accurate enough to use to develop preliminary building designs within a short proposal time limit, usually within 60 days. The NASA Prediction Of Worldwide Energy Resource (POWER) project was established by NASA to provide industry friendly access to globally distributed solar and meteorological data. As a result, the POWER web site (power.larc.nasa.gov) now provides global information on many renewable energy parameters and several buildings-related items but at a relatively coarse resolution. This paper describes a method of downscaling NASA atmospheric assimilation model results to higher resolution and maps those parameters to produce building climate zone maps using estimates of temperature and precipitation. The distribution of climate zones for North America with an emphasis on the Pacific Northwest for just one year shows very good correspondence to the currently defined distribution. The method has the potential to provide a consistent procedure for deriving climate zone information on a global basis that can be assessed for variability and updated more regularly.

  13. Multiclass Classification of Agro-Ecological Zones for Arabica Coffee: An Improved Understanding of the Impacts of Climate Change.

    PubMed

    Bunn, Christian; Läderach, Peter; Pérez Jimenez, Juan Guillermo; Montagnon, Christophe; Schilling, Timothy

    2015-01-01

    Cultivation of Coffea arabica is highly sensitive to and has been shown to be negatively impacted by progressive climatic changes. Previous research contributed little to support forward-looking adaptation. Agro-ecological zoning is a common tool to identify homologous environments and prioritize research. We demonstrate here a pragmatic approach to describe spatial changes in agro-climatic zones suitable for coffee under current and future climates. We defined agro-ecological zones suitable to produce arabica coffee by clustering geo-referenced coffee occurrence locations based on bio-climatic variables. We used random forest classification of climate data layers to model the spatial distribution of these agro-ecological zones. We used these zones to identify spatially explicit impact scenarios and to choose locations for the long-term evaluation of adaptation measures as climate changes. We found that in zones currently classified as hot and dry, climate change will impact arabica more than those that are better suited to it. Research in these zones should therefore focus on expanding arabica's environmental limits. Zones that currently have climates better suited for arabica will migrate upwards by about 500m in elevation. In these zones the up-slope migration will be gradual, but will likely have negative ecosystem impacts. Additionally, we identified locations that with high probability will not change their climatic characteristics and are suitable to evaluate C. arabica germplasm in the face of climate change. These locations should be used to investigate long term adaptation strategies to production systems.

  14. Multiclass Classification of Agro-Ecological Zones for Arabica Coffee: An Improved Understanding of the Impacts of Climate Change

    PubMed Central

    Bunn, Christian; Läderach, Peter; Pérez Jimenez, Juan Guillermo; Montagnon, Christophe; Schilling, Timothy

    2015-01-01

    Cultivation of Coffea arabica is highly sensitive to and has been shown to be negatively impacted by progressive climatic changes. Previous research contributed little to support forward-looking adaptation. Agro-ecological zoning is a common tool to identify homologous environments and prioritize research. We demonstrate here a pragmatic approach to describe spatial changes in agro-climatic zones suitable for coffee under current and future climates. We defined agro-ecological zones suitable to produce arabica coffee by clustering geo-referenced coffee occurrence locations based on bio-climatic variables. We used random forest classification of climate data layers to model the spatial distribution of these agro-ecological zones. We used these zones to identify spatially explicit impact scenarios and to choose locations for the long-term evaluation of adaptation measures as climate changes. We found that in zones currently classified as hot and dry, climate change will impact arabica more than those that are better suited to it. Research in these zones should therefore focus on expanding arabica's environmental limits. Zones that currently have climates better suited for arabica will migrate upwards by about 500m in elevation. In these zones the up-slope migration will be gradual, but will likely have negative ecosystem impacts. Additionally, we identified locations that with high probability will not change their climatic characteristics and are suitable to evaluate C. arabica germplasm in the face of climate change. These locations should be used to investigate long term adaptation strategies to production systems. PMID:26505637

  15. Climate zone delineation: evaluating approaches for use in natural resource management.

    PubMed

    Tercek, Michael T; Gray, Stephen T; Nicholson, Christopher M

    2012-05-01

    Recent efforts by the United States Department of the Interior (DOI) have the potential to make climate zones the basic geographic units guiding monitoring and resource management programs in the western U.S. We evaluated a new National Park Service approach for delineating climate zones that will likely be a model for other DOI agencies. Using the test case of the Greater Yellowstone Area in Wyoming, Montana and Idaho, we conducted three separate analyses, each based on a different dataset. Cluster analysis of 1971-2000 temperature and precipitation normals grouped weather stations according to similarities in seasonal patterns. Principal Components Analysis (PCAs) of 1895-2008 monthly data grouped stations by similarities in long-term variability. Finally, an analysis of snow data further subdivided the zones defined by the other two analyses. The climate zones produced by the cluster analysis and the PCAs were roughly similar to each other, but the differences were significant. The two sets of zones may be useful for different applications. For example, studies that analyze links between climate patterns and the demography of threatened species should focus on the results of the PCAs. The broad similarity among results produced by the different approaches supported the application of these zones in climate-related monitoring and analysis. However, since choices in data and methodology can affect the details of maps depicting zone boundaries, there are practical limitations to their use.

  16. Zoning of cold stress associated with climatic change in Russia

    SciTech Connect

    Vinogradova, V.V.

    1997-12-31

    The purpose of my work is to learn the connection of geographical zonality with the distribution of stress in Russia. The map {open_quotes}Geographical distribution of climate life condition ranged on the degree of discomfort in Russia{close_quotes}, made in Institute of Geography of Russian Academy of Sciences, reflects the zoning of cold stress in Russia. This zoning was used for the estimation of cold stress in Russia at various screenplays of climate change. The base of zoning was mating of boundaries of nature-climatic zonality with characteristics of cold presented by indices of cold stress (enthalpy, dry cooling, wet cooling, wind chill etc.). The paper covers geographical distribution of factors provoking cold stress: low temperatures, wind speed and air humidity. Zoning of cold stress on the territory of Russia for long standing average conditions and for the periods of cooling and warming of global climate in the XX century was performed.

  17. Defining and Responding to Issues of Canada's Coastal Zones.

    ERIC Educational Resources Information Center

    Diamond, Lawrence

    1984-01-01

    Defines and discusses critical issues for each of Canada's coastal regions (Pacific, Arctic, Atlantic, and Great Lakes) in environmental, technological, social, and political contexts; reviews recent efforts to obtain and use environmental information; and highlights alternative ways of achieving better stewardship. (Author/DH)

  18. Defining and Responding to Issues of Canada's Coastal Zones.

    ERIC Educational Resources Information Center

    Diamond, Lawrence

    1984-01-01

    Defines and discusses critical issues for each of Canada's coastal regions (Pacific, Arctic, Atlantic, and Great Lakes) in environmental, technological, social, and political contexts; reviews recent efforts to obtain and use environmental information; and highlights alternative ways of achieving better stewardship. (Author/DH)

  19. San Andreas tremor cascades define deep fault zone complexity

    USGS Publications Warehouse

    Shelly, David R.

    2015-01-01

    Weak seismic vibrations - tectonic tremor - can be used to delineate some plate boundary faults. Tremor on the deep San Andreas Fault, located at the boundary between the Pacific and North American plates, is thought to be a passive indicator of slow fault slip. San Andreas Fault tremor migrates at up to 30 m s-1, but the processes regulating tremor migration are unclear. Here I use a 12-year catalogue of more than 850,000 low-frequency earthquakes to systematically analyse the high-speed migration of tremor along the San Andreas Fault. I find that tremor migrates most effectively through regions of greatest tremor production and does not propagate through regions with gaps in tremor production. I interpret the rapid tremor migration as a self-regulating cascade of seismic ruptures along the fault, which implies that tremor may be an active, rather than passive participant in the slip propagation. I also identify an isolated group of tremor sources that are offset eastwards beneath the San Andreas Fault, possibly indicative of the interface between the Monterey Microplate, a hypothesized remnant of the subducted Farallon Plate, and the North American Plate. These observations illustrate a possible link between the central San Andreas Fault and tremor-producing subduction zones.

  20. On validation of the rain climatic zone designations for Nigeria

    NASA Astrophysics Data System (ADS)

    Obiyemi, O. O.; Ibiyemi, T. S.; Ojo, J. S.

    2017-07-01

    In this paper, validation of rain climatic zone classifications for Nigeria is presented based on global radio-climatic models by the International Telecommunication Union-Radiocommunication (ITU-R) and Crane. Rain rate estimates deduced from several ground-based measurements and those earlier estimated from the precipitation index on the Tropical Rain Measurement Mission (TRMM) were employed for the validation exercise. Although earlier classifications indicated that Nigeria falls into zones P, Q, N, and K for the ITU-R designations, and zones E and H for Crane's climatic zone designations, the results however confirmed that the rain climatic zones across Nigeria can only be classified into four, namely P, Q, M, and N for the ITU-R designations, while the designations by Crane exhibited only three zones, namely E, G, and H. The ITU-R classification was found to be more suitable for planning microwave and millimeter wave links across Nigeria. The research outcomes are vital in boosting the confidence level of system designers in using the ITU-R designations as presented in the map developed for the rain zone designations for estimating the attenuation induced by rain along satellite and terrestrial microwave links over Nigeria.

  1. On validation of the rain climatic zone designations for Nigeria

    NASA Astrophysics Data System (ADS)

    Obiyemi, O. O.; Ibiyemi, T. S.; Ojo, J. S.

    2016-04-01

    In this paper, validation of rain climatic zone classifications for Nigeria is presented based on global radio-climatic models by the International Telecommunication Union-Radiocommunication (ITU-R) and Crane. Rain rate estimates deduced from several ground-based measurements and those earlier estimated from the precipitation index on the Tropical Rain Measurement Mission (TRMM) were employed for the validation exercise. Although earlier classifications indicated that Nigeria falls into zones P, Q, N, and K for the ITU-R designations, and zones E and H for Crane's climatic zone designations, the results however confirmed that the rain climatic zones across Nigeria can only be classified into four, namely P, Q, M, and N for the ITU-R designations, while the designations by Crane exhibited only three zones, namely E, G, and H. The ITU-R classification was found to be more suitable for planning microwave and millimeter wave links across Nigeria. The research outcomes are vital in boosting the confidence level of system designers in using the ITU-R designations as presented in the map developed for the rain zone designations for estimating the attenuation induced by rain along satellite and terrestrial microwave links over Nigeria.

  2. Control of climate and litter quality on leaf litter decomposition in different climatic zones.

    PubMed

    Zhang, Xinyue; Wang, Wei

    2015-09-01

    Climate and initial litter quality are the major factors influencing decomposition rates on large scales. We established a comprehensive database of terrestrial leaf litter decomposition, including 785 datasets, to examine the relationship between climate and litter quality and evaluate the factors controlling decomposition on a global scale, the arid and semi-arid (AS) zone, the humid middle and humid low (HL) latitude zones. Initial litter nitrogen (N) and phosphorus (P) concentration only increased with mean annual temperature (MAT) in the AS zone and decreased with mean annual precipitation (MAP) in the HL zone. Compared with nutrient content, MAT imposed less effect on initial litter lignin content than MAP. MAT were the most important decomposition driving factors on a global scale as well as in different climatic zones. MAP only significantly affected decomposition constants in AS zone. Although litter quality parameters also showed significant influence on decomposition, their importance was less than the climatic factors. Besides, different litter quality parameters exerted significant influence on decomposition in different climatic zones. Our results emphasized that climate consistently exerted important effects on decomposition constants across different climatic zones.

  3. Defining the Sudden Stratospheric Warming in Climate Models

    NASA Astrophysics Data System (ADS)

    Kim, J.; Son, S. W.; Gerber, E. P.; Park, H. S.

    2016-12-01

    A sudden stratospheric warming (SSW) is defined by the World Meteorological Organization (WMO) as zonal-mean zonal wind reversal at 10 hPa and 60°N, associated with a reversal of the climatological temperature gradient at this elevation. This wind criterion in particular has been applied to reanalysis data and climate model output during the last few decades. In the present study, it is shown that the application of this definition to models can be affected by model mean biases; i.e., more frequent SSW appears to occur in models with a weaker climatological polar vortex. In order to overcome this deficiency, a tendency-based definition, which is not sensitive to the model mean bias, is proposed and applied to the multi-model data sets archived for the Coupled Model Intercomparison Projection phase 5 (CMIP5). In this definition, SSW-like events are defined by sufficiently strong vortex deceleration. This approach removes a linear relationship between the SSW frequency and intensity of climatological polar vortex for both the low-top and high-top CMIP5 models. Instead, the resulting SSW frequency is strongly correlated with wave activity at 100 hPa. The two definitions detect quantitatively different SSW in terms of lower stratospheric wave activity and downward propagation of stratospheric anomalies to the troposphere. However, in both definitions, the high-top models generally exhibit more frequent SSW than the low-top models. Moreover, a hint of more frequent SSW in a warm climate is commonly found.

  4. Influence of soil and climate on root zone storage capacity

    NASA Astrophysics Data System (ADS)

    Euser, Tanja; McMillan, Hilary; Hrachowitz, Markus; Winsemius, Hessel; Savenije, Hubert

    2015-04-01

    The root zone water storage capacity (Sr) of a catchment is an important variable for the hydrological behaviour of a catchment; it strongly influences the storage, transpiration and runoff generation in an area. However, the root zone storage capacity is largely heterogeneous and not measurable. There are different theories about the variables affecting the root zone storage capacity; among the most debated are soil, vegetation and climate. The effect of vegetation and soil is often accounted for by detailed soil and land use maps. To investigate the effect of climate on the root zone storage capacity, an analogue can be made between the root zone storage capacity of a catchment and the human habit to design and construct reservoirs: both storage capacities help to overcome a dry period of a certain length. Humans often use the mass curve technique to determine the required storage needed to design the reservoir capacity. This mass curve technique can also be used to derive the root zone storage capacity created by vegetation in a certain ecosystem and climate (Gao et al., 2014). Only precipitation and discharge or evaporation data are required for this method. This study tests whether Sr values derived by both the mass curve technique and from soil maps are comparable for a range of catchments in New Zealand. Catchments are selected over a gradient of climates and land use. Special focus lies on how Sr values derived for a larger catchment are representative for smaller nested catchments. The spatial differences are examined between values derived from soil data and from climate and flow data. Gao, H., Hrachowitz, M., Schymanski, S.J., Fenicia, F., Sriwongsitanon, N., Savenije, H.H.G, (2014): Climate controls how ecosystems size the root zone storage capacity at catchment scale. DOI: 10.1002/2014GL061668

  5. Fire season climatic zones of mainland Alaska.

    Treesearch

    William M. Trigg

    1971-01-01

    Calculated values of precipitation effectiveness index and temperature efficiency index for 48 weather observation stations on the Alaska mainland are used to delineate areas that have different climatic subclassifications during the wildfire season of April through September. The paper outlines procedures, provides maps showing step- by- step analysis along with the...

  6. Defining fire environment zones in the boreal forests of northeastern China.

    PubMed

    Wu, Zhiwei; He, Hong S; Yang, Jian; Liang, Yu

    2015-06-15

    Fire activity in boreal forests will substantially increase with prolonged growing seasons under a warming climate. This trend poses challenges to managing fires in boreal forest landscapes. A fire environment zone map offers a basis for evaluating these fire-related problems and designing more effective fire management plans to improve the allocation of management resources across a landscape. Toward that goal, we identified three fire environment zones across boreal forest landscapes in northeastern China using analytical methods to identify spatial clustering of the environmental variables of climate, vegetation, topography, and human activity. The three fire environment zones were found to be in strong agreement with the spatial distributions of the historical fire data (occurrence, size, and frequency) for 1966-2005. This paper discusses how the resulting fire environment zone map can be used to guide forest fire management and fire regime prediction. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Sensitivity of Vadose Zone Water Fluxes to Climate Shifts in Arid Settings

    SciTech Connect

    Pfletschinger, H.; Prömmel, K.; Schüth, C.; Herbst, M.; Engelhardt, I.

    2014-01-01

    Vadose zone water fluxes in arid settings are investigated regarding their sensitivity to hydraulic soil parameters and meteorological data. The study is based on the inverse modeling of highly defined soil column experiments and subsequent scenario modeling comparing different climate projections for a defined arid region. In arid regions, groundwater resources are prone to depletion due to excessive water use and little recharge potential. Especially in sand dune areas, groundwater recharge is highly dependent on vadose zone properties and corresponding water fluxes. Nevertheless, vadose zone water fluxes under arid conditions are hard to determine owing to, among other reasons, deep vadose zones with generally low fluxes and only sporadic high infiltration events. In this study, we present an inverse model of infiltration experiments accounting for variable saturated nonisothermal water fluxes to estimate effective hydraulic and thermal parameters of dune sands. A subsequent scenario modeling links the results of the inverse model with projections of a global climate model until 2100. The scenario modeling clearly showed the high dependency of groundwater recharge on precipitation amounts and intensities, whereas temperature increases are only of minor importance for deep infiltration. However, simulated precipitation rates are still affected by high uncertainties in the response to the hydrological input data of the climate model. Thus, higher certainty in the prediction of precipitation pattern is a major future goal for climate modeling to constrain future groundwater management strategies in arid regions.

  8. Influence of soil and climate on root zone storage capacity

    NASA Astrophysics Data System (ADS)

    de Boer-Euser, Tanja; McMillan, Hilary; Hrachowitz, Markus; Winsemius, Hessel; Savenije, Hubert

    2016-04-01

    The catchment representative root zone storage capacity (Sr), i.e. the plant available soil water, is an important parameter of hydrological systems. It does not only influence the runoff from catchments, by controlling the partitioning of water fluxes but it also influences the local climate, by providing the source for transpiration. Sr is difficult to observe at catchment scale, due to heterogeneities in vegetation and soils. Sr estimates are traditionally derived from soil characteristics and estimates of root depths. In contrast, a recently suggested method allows the determination of Sr based on climate data, i.e. precipitation and evaporation, alone (Gao et al., 2014). By doing so, the time-variable size of Sr, is explicitly accounted for, which is not the case for traditional soil based methods. The time-variable size of Sr reflects root growth and thus the vegetation's adaption to medium-term fluctuations in the climate. Thus, we tested and compared Sr estimates from this 'climate based method' with estimates from soil data for 32 catchments in New Zealand. The results show a larger range in climate derived Sr than in soil derived Sr. Using a model experiment, we show that a model using the climate derived Sr is more accurately able to reproduce a set of hydrological regime signatures, in particular for humid catchments. For more arid catchments, the two methods provide similar model results. This implies that, although soil database information has some predictive power for model soil storage capacity, climate has a similar or greater control on Sr, as climate affects the evolving hydrological functioning of the root zone at the time scale of hydrological interest. In addition, Sr represents the plant available water and thus root surface, volume and density, and is therefore a more complete descriptor of vegetation influence on water fluxes than mere root depth. On balance, the results indicate that climate has a higher explanatory power than soils for

  9. [Defining of wheat growth management zones based on remote sensing and geostatistics].

    PubMed

    Huang, Yan; Zhu, Yan; Ma, Meng-Li; Wang, Hang; Cao, Wei-Xing; Tian, Yong-Chao

    2011-02-01

    Taking the winter wheat planting areas in Rugao City and Haian County of Jiangsu Province as test objects, the clustering defining of wheat growth management zones was made, based on the spatial variability analysis and principal component extraction of the normalized difference vegetation index (NDVI) data calculated from the HJ-1A/B CCD images (30 m resolution) at different growth stages of winter wheat, and of the soil nutrient indices (total nitrogen, organic matter, available phosphorus, and available potassium). The results showed that the integration of the NDVI at heading stage with above-mentioned soil nutrient indices produced the best results of wheat growth management zone defining, with the variation coefficients of NDVI and soil nutrient indices in each defined zone ranged in 4.5% -6.1% and 3.3% -87.9%, respectively. However, the variation coefficients were much larger when the wheat growth management zones were defined individually by NDVI or by soil nutrient indices, suggesting that the newly developed defining method could reduce the variability within the defined management zones and improve the crop management precision, and thereby, contribute to the winter wheat growth management and process simulation at regional scale.

  10. Climate-mediated movement of an avian hybrid zone.

    PubMed

    Taylor, Scott A; White, Thomas A; Hochachka, Wesley M; Ferretti, Valentina; Curry, Robert L; Lovette, Irby

    2014-03-17

    The interaction between sibling species that share a zone of contact is a multifaceted relationship affected by climate change [1, 2]. Between sibling species, interactions may occur at whole-organism (direct or indirect competition) or genomic (hybridization and introgression) levels [3-5]. Tracking hybrid zone movements can provide insights about influences of environmental change on species interactions [1]. Here, we explore the extent and mechanism of movement of the contact zone between black-capped chickadees (Poecile atricapillus) and Carolina chickadees (Poecile carolinensis) at whole-organism and genomic levels. We find strong evidence that winter temperatures limit the northern extent of P. carolinensis by demonstrating a current-day association between the range limit of this species and minimum winter temperatures. We further show that this temperature limitation has been consistent over time because we are able to accurately hindcast the previous northern range limit under earlier climate conditions. Using genomic data, we confirm northward movement of this contact zone over the past decade and highlight temporally consistent differential-but limited-geographic introgression of alleles. Our results provide an informative example of the influence of climate change on a contact zone between sibling species.

  11. Influence of soil and climate on root zone storage capacity

    NASA Astrophysics Data System (ADS)

    de Boer-Euser, T.; McMillan, H.; Hrachowitz, M.; Winsemius, H.; Savenije, H.

    2015-12-01

    The catchment representative root zone storage capacity (Sr), i.e. the plant available soil water, is an important parameter of hydrological systems. It does not only influence the runoff from catchments, by controlling the partitioning of water fluxes but it also influences the local climate, by providing the source for transpiration. Sr is difficult to observe at catchment scale, due to heterogeneities in vegetation and soils. Sr estimates are traditionally derived from soil characteristics and estimates of root depths. In contrast, a recently suggested method allows the determination of Sr based on climate data, i.e. precipitation and evaporation, alone (Gao et al., 2014). By doing so, the time-variable size of Sr, is explicitly accounted for, which is not the case for traditional soil based methods. The time-variable size of Sr reflects root growth and thus the vegetation's adaption to medium-term fluctuations in the climate. Thus, we tested and compared Sr estimates from this 'climate based method' with estimates from soil data for 32 catchments in New Zealand. The results show a larger range in climate derived Sr than in soil derived Sr. Using a model experiment, we show that a model using the climate derived Sr is more accurately able to reproduce a set of hydrological regime signatures, in particular for humid catchments. For more arid catchments, the two methods provide similar model results. This implies that, although soil information has some predictive power for Sr, climate has a similar or greater control on Sr, as climate affects the evolving hydrological functioning of the root zone at the time scale of hydrological interest. In addition, Sr represents the plant available water and thus root surface, volume and density, and is therefore a more complete descriptor of vegetation influence on water fluxes than mere root depth. On balance, the results indicate that climate has a higher explanatory power than soils for catchment representative Sr.

  12. Weather, not climate, defines distributions of vagile bird species.

    PubMed

    Reside, April E; Vanderwal, Jeremy J; Kutt, Alex S; Perkins, Genevieve C

    2010-10-22

    Accurate predictions of species distributions are essential for climate change impact assessments. However the standard practice of using long-term climate averages to train species distribution models might mute important temporal patterns of species distribution. The benefit of using temporally explicit weather and distribution data has not been assessed. We hypothesized that short-term weather associated with the time a species was recorded should be superior to long-term climate measures for predicting distributions of mobile species. We tested our hypothesis by generating distribution models for 157 bird species found in Australian tropical savannas (ATS) using modelling algorithm Maxent. The variable weather of the ATS supports a bird assemblage with variable movement patterns and a high incidence of nomadism. We developed "weather" models by relating climatic variables (mean temperature, rainfall, rainfall seasonality and temperature seasonality) from the three month, six month and one year period preceding each bird record over a 58 year period (1950-2008). These weather models were compared against models built using long-term (30 year) averages of the same climatic variables. Weather models consistently achieved higher model scores than climate models, particularly for wide-ranging, nomadic and desert species. Climate models predicted larger range areas for species, whereas weather models quantified fluctuations in habitat suitability across months, seasons and years. Models based on long-term climate averages over-estimate availability of suitable habitat and species' climatic tolerances, masking species potential vulnerability to climate change. Our results demonstrate that dynamic approaches to distribution modelling, such as incorporating organism-appropriate temporal scales, improves understanding of species distributions.

  13. Weather, Not Climate, Defines Distributions of Vagile Bird Species

    PubMed Central

    Reside, April E.; VanDerWal, Jeremy J.; Kutt, Alex S.; Perkins, Genevieve C.

    2010-01-01

    Background Accurate predictions of species distributions are essential for climate change impact assessments. However the standard practice of using long-term climate averages to train species distribution models might mute important temporal patterns of species distribution. The benefit of using temporally explicit weather and distribution data has not been assessed. We hypothesized that short-term weather associated with the time a species was recorded should be superior to long-term climate measures for predicting distributions of mobile species. Methodology We tested our hypothesis by generating distribution models for 157 bird species found in Australian tropical savannas (ATS) using modelling algorithm Maxent. The variable weather of the ATS supports a bird assemblage with variable movement patterns and a high incidence of nomadism. We developed “weather” models by relating climatic variables (mean temperature, rainfall, rainfall seasonality and temperature seasonality) from the three month, six month and one year period preceding each bird record over a 58 year period (1950–2008). These weather models were compared against models built using long-term (30 year) averages of the same climatic variables. Conclusions Weather models consistently achieved higher model scores than climate models, particularly for wide-ranging, nomadic and desert species. Climate models predicted larger range areas for species, whereas weather models quantified fluctuations in habitat suitability across months, seasons and years. Models based on long-term climate averages over-estimate availability of suitable habitat and species' climatic tolerances, masking species potential vulnerability to climate change. Our results demonstrate that dynamic approaches to distribution modelling, such as incorporating organism-appropriate temporal scales, improves understanding of species distributions. PMID:21042575

  14. Investigating the Climatic Transition Zone in Guyana, South America

    NASA Astrophysics Data System (ADS)

    Bovolo, C.; Pereira, R.; Parkin, G.; Kilsby, C. G.; Wagner, T.

    2010-12-01

    The climate of Guyana is influenced by the seasonal oscillation of the rain-bearing Inter-Tropical-Convergence Zone over the northern part of South America, producing two wet seasons on the coast and one wet season inland. The transition zone between the two climate regimes also corresponds to a distinct vegetation transition between intact and highly biodiverse rainforests in northern and central Guyana, and open, savannah type vegetation in the southwest. Coastal Guyana has been shown to be highly susceptible to El Niño Southern Oscillation (ENSO) events, with El-Niño conditions most likely to result in drought; however a brief analysis of available observations suggests that an opposite effect may exist inland. Geographically sparse meteorological records of variable quality (especially inland) have so far precluded detailed climatic studies of the Guianas. It is important therefore, to establish the climate regime of the area and to analyse the influence of ENSO on the region in order to derive baselines against which the impacts of any future landuse change or climate change can be measured. The impacts of climatic variations on the ecosystem services of the area can then also begin to be determined. This study compares the ECMWF ERA40 reanalysis dataset for the period 1957-2002 at a ~125 km2 (1.125 degree) resolution against available areally averaged meteorological observations in the Guyanas to determine if reanalysis data can be used to supplement observations in data-poor areas. Mean differences (biases) and correlations are examined comparing the seasonal cycles and the yearly, monthly and monthly anomaly time series. Results show that maps of average annual reanalysis precipitation for the region compare favourably against observations, although the model underestimates precipitation in some zones of higher elevation. ERA40 also appears slightly positively biased on the coast and negatively biased inland. Correlations between observed and modelled

  15. Visualizing Life Zone Boundary Sensitivities Across Climate Models and Temporal Spans

    SciTech Connect

    Sisneros, Roberto R; Huang, Jian; Ostrouchov, George; Hoffman, Forrest M

    2011-01-01

    Life zones are a convenient and quantifiable method for delineating areas with similar plant and animal communities based on bioclimatic conditions. Such ecoregionalization techniques have proved useful for defining habitats and for studying how these habitats may shift due to environmental change. The ecological impacts of climate change are of particular interest. Here we show that visualizations of the geographic projection of life zones may be applied to the investigation of potential ecological impacts of climate change using the results of global climate model simulations. Using a multi-factor classification scheme, we show how life zones change over time based on quantitative model results into the next century. Using two straightforward metrics, we identify regions of high sensitivity to climate changes from two global climate simulations under two different greenhouse gas emissions scenarios. Finally, we identify how preferred human habitats may shift under these scenarios. We apply visualization methods developed for the purpose of displaying multivariate relationships within data, especially for situations that involve a large number of concurrent relationships. Our method is based on the concept of multivariate classification, and is implemented directly in VisIt, a production quality visualization package.

  16. Influence of soil and climate on root zone storage capacity

    NASA Astrophysics Data System (ADS)

    Boer-Euser, Tanja; McMillan, Hilary K.; Hrachowitz, Markus; Winsemius, Hessel C.; Savenije, Hubert H. G.

    2016-03-01

    Root zone storage capacity (Sr) is an important variable for hydrology and climate studies, as it strongly influences the hydrological functioning of a catchment and, via evaporation, the local climate. Despite its importance, it remains difficult to obtain a well-founded catchment representative estimate. This study tests the hypothesis that vegetation adapts its Sr to create a buffer large enough to sustain the plant during drought conditions of a certain critical strength (with a certain probability of exceedance). Following this method, Sr can be estimated from precipitation and evaporative demand data. The results of this "climate-based method" are compared with traditional estimates from soil data for 32 catchments in New Zealand. The results show that the differences between catchments in climate-derived catchment representative Sr values are larger than for soil-derived Sr values. Using a model experiment, we show that the climate-derived Sr can better reproduce hydrological regime signatures for humid catchments; for more arid catchments, the soil and climate methods perform similarly. This makes the climate-based Sr a valuable addition for increasing hydrological understanding and reducing hydrological model uncertainty.

  17. Defining Canadian Perspectives on Climate Change Science and Solutions

    NASA Astrophysics Data System (ADS)

    Rieger, C.; Byrne, J. M.

    2014-12-01

    Despite the overwhelming scientific evidence of potentially disastrous change in global climate, little is being accomplished in climate mitigation or adaptation in Canada. The energy sector in Canada is still primarily oil and gas, with huge tax breaks to the industry in spite of well known harmful regional and global impacts of fossil fuel pollution. One of the largest concerns for the climate science community is the variable and often complacent attitude many Canadians share on the issue of climate change. The objective herein is twofold: (1) a survey tool will be used to assess the views and opinions of Canadians on climate change science and solutions; (2) develop better communication methods for industry, government and NGOs to share the science and solutions with the public. The study results will inform the Canadian public, policy makers and industry of practical, effective changes needed to address climate change challenges. A survey of Canadians' perspectives is an important step in policy changing research. The climate research and application community must know the most effective ways to communicate the science and solutions with a public that is often resistant to change. The AGU presentation will feature the results of the survey, while continued work into 2015 will be towards advancing communication. This study is both timely and crucial for science communicators in understanding how Canadians view climate change, considering, for example, devastatingly extreme weather being experienced of late and its effect on the economy. The results will assist in recognizing how to encourage Canadians to work towards a more sustainable and resilient energy sector in Canada and abroad.

  18. Defining, Assessing, and Improving Community Junior College Instructional Climate.

    ERIC Educational Resources Information Center

    Romine, Stephen; Newport, Donald L.

    A study was conducted to determine the perceptions of students and faculty members concerning an effective instructional climate in which satisfying and successful teaching and learning occur. A questionnaire was developed for use as a means of gaining such perceptions in terms of 70 possible attributes. Usable responses were received from 2,058…

  19. Analysis of projected climate change in the Carpathian Basin region based on Holdridge life zone system

    NASA Astrophysics Data System (ADS)

    Szelepcsényi, Zoltán; Breuer, Hajnalka; Sümegi, Pál

    2014-05-01

    Nowadays more and more environmental lobbyists believe that climate change must be demonstrated in a new form. The estimated temperature increase can be realized more easily, if the emphasis is on ecological effects of the predicted temperature. For this reason a bioclimatic classification method was used to analyse the projected changes for the Carpathian Basin region. We applied the Holdridge life zone system, which is relatively simple, so our results can be used to inform the population. Holdridge developed a geometric model for climate classification which declares the relationship between classes (life zones) and climate indices (mean annual biotemperature, average total annual precipitation, potential evapotranspiration ratio). The necessary data for this study was derived from regional climate model (RCM) experiments of the ENSEMBLES project using the SRES A1B emission scenario. The temperature and precipitation data series were bias corrected for the selected RCM simulations. The target area of our investigations is the Carpathian Basin region. Life zones maps were created using the selected RCM simulations and their ensemble mean for the periods: 1961-1990 (T1), 2021-2050 (T2), 2061-2090 (T3). The spatial distribution of life zones and their temporal changes were investigated. According to our results the spatial pattern of life zones changes significantly from T1 to T3. It is possible that some types of life zones (e.g. boreal rain forest) will disappear; and some types (e.g. warm temperate thorn steppe) will appear in the target area. We determined those RCM simulations which predicted the maximum and minimum changes of the spatial pattern of life zones. Maps of T1 were compared to maps of T3 using Cohen's Kappa coefficient. Furthermore, relative extents, vertical distribution patterns and mean centres of life zones have been analysed. These parameters were defined for each decade and also for T1, T2 and T3. The temporal changes of the decadal values

  20. Edge-defined contact heater apparatus and method for floating zone crystal growth

    NASA Technical Reports Server (NTRS)

    Kou, Sindo (Inventor)

    1992-01-01

    An apparatus for growing a monocrystalline body (30) from a polycrystalline feed rod (22) includes a heater (20) that is positioned to heat a short section of the polycrystalline rod (22) to create a molten zone (34). The heater (20) is formed to include a shaper (40) that contacts the polycrystalline rod (22) in the molten zone (34) and has a hole (46) to allow flow in the molten zone (34) between the polycrystalline rod (22) side and the monocrystalline body (30) side of the shaper. The shaper (40) has an edge (42) that defines the boundary of the cross-section of the monocrystalline body (30) that is formed as the molten material solidifies.

  1. Climate Variability and Vadose Zone Controls on Damping of Transient Recharge Fluxes

    NASA Astrophysics Data System (ADS)

    Corona, C.; Gurdak, J. J.; Dickinson, J.; Ferré, T. P. A.

    2015-12-01

    We investigate the effects of interannual to multidecadal climate variability on groundwater resources by exploring the physical processes in the vadose zone that partially control transient infiltration and recharge fluxes. The vadose zone connects climate variability modes to groundwater systems by influencing infiltration events. Infiltration events become time-varying water flux through the vadose zone and are controlled by highly nonlinear, complex interactions between mean infiltration flux, infiltration period, soil textures, and depth to water table. We focus on the behavior and damping depth of water flux in the vadose zone. The damping depth is defined as the depth that the flux variation damps to 5% of the land surface variation. When the damping depth is above the water table, recharge may be considered steady; when the damping depth is below the water table, recharge may be considered transient. Previous work shows that the damping depth is sensitive to the frequency of the infiltration pattern and the unsaturated hydraulic properties of the media. We examine controls on the damping depth by modeling transient water fluxes at the land surface using the Gardner-Kozeny soil model for diffuse unsaturated flow in HYDRUS 1-D. Results for homogeneous profiles show that shorter-period oscillations, smaller mean fluxes, and finer-grained soil textures generally produce damping depths closer to land surface. Modeling layered soil textures indicates similar, but more complicated responses in the damping depth. Model results indicate that finer-textured layers in a coarser soil profile generally result in damping depths closer to land surface, while coarser-textured layers in a coarser soil profile result in damping depths deeper in the vadose zone. Findings from this study will enhance understanding of the vadose zone's influence on transient water flux and improve the simulation of recharge processes and climate variability effects in groundwater models.

  2. An Assessment of Actual and Potential Building Climate Zone Change and Variability From the Last 30 Years Through 2100 Using NASA's MERRA and CMIP5 Simulations

    NASA Technical Reports Server (NTRS)

    Stackhouse, Paul W., Jr.; Chandler, William S.; Hoell, James M.; Westberg, David; Zhang, Taiping

    2015-01-01

    Background: In the US, residential and commercial building infrastructure combined consumes about 40% of total energy usage and emits about 39% of total CO2 emission (DOE/EIA "Annual Energy Outlook 2013"). Building codes, as used by local and state enforcement entities are typically tied to the dominant climate within an enforcement jurisdiction classified according to various climate zones. These climate zones are based upon a 30-year average of local surface observations and are developed by DOE and ASHRAE. Establishing the current variability and potential changes to future building climate zones is very important for increasing the energy efficiency of buildings and reducing energy costs and emissions in the future. Objectives: This paper demonstrates the usefulness of using NASA's Modern Era Retrospective-analysis for Research and Applications (MERRA) atmospheric data assimilation to derive the DOE/ASHRAE building climate zone maps and then using MERRA to define the last 30 years of variability in climate zones for the Continental US. An atmospheric assimilation is a global atmospheric model optimized to satellite, atmospheric and surface in situ measurements. Using MERRA as a baseline, we then evaluate the latest Climate Model Inter-comparison Project (CMIP) climate model Version 5 runs to assess potential variability in future climate zones under various assumptions. Methods: We derive DOE/ASHRAE building climate zones using surface and temperature data products from MERRA. We assess these zones using the uncertainties derived by comparison to surface measurements. Using statistical tests, we evaluate variability of the climate zones in time and assess areas in the continental US for statistically significant trends by region. CMIP 5 produced a data base of over two dozen detailed climate model runs under various greenhouse gas forcing assumptions. We evaluate the variation in building climate zones for 3 different decades using an ensemble and quartile

  3. Pacific Northwest residential energy survey. Volume 9. Climate Zone 1 cross-tabulations

    SciTech Connect

    Not Available

    1980-07-01

    Responses for Climate Zone 1 to fifty questions asked during the survey (plus four variables computed from responses to several other questions) are presented. Climate Zone 1, defined according to the sum of heating and cooling degree days, amounts to less than 6000. The fifty questions were cross-tabulated against responses to nine questions which represent key explanatory characteristics of residential energy use. The nine key questions are: means of payment for housing; type of dwelling; year dwelling built; total square-footage of living space; type of fuel for main heating system; combined 1978 income; unit cost of electricity; annual electricity consumption; and annual natural gas consumption. The fifty questions and four computed variables which were cross-tabulated against the above fall into six categories; dwelling characteristics; heating and air-conditioning systems; water heating; appliances; demographic and dwelling characteristics; and insulation. The survey was conducted throughout the states of Washington, Oregon, Idaho, and Montana, with a total of 4030 households sampled; 1873 households were sampled in Climate Zone 1. Information in 54 tables is explained. (MCW)

  4. Pacific Northwest residential energy survey. Volume 10. Climate Zone 2 cross-tabulations

    SciTech Connect

    Not Available

    1980-07-01

    Responses for Climate Zone 2 to fifty questions asked during the survey (plus four variables computed from responses to several other questions) are presented. Climate Zone 2, defined according to the sum of heating and cooling degree days, amounts to 6000 to 6999. The fifty questions were cross-tabulated against responses to nine questions which represent key explanatory characteristics of residential energy use. The nine key questions are: means of payment for housing; type of dwelling; year dwelling built; total square-footage of living space; type of fuel for main heating system; combined 1978 income; unit cost of electricity; annual electricity consumption; and annual natural gas consumption. The fifty questions and four computed variables which were cross-tabulated against the above fall into six categories: dwelling characteristics; heating and air-conditioning systems; water heating; appliances; demographic and dwelling characteristics; and insulation. The survey was conducted throughout the states of Washington, Oregon, Idaho, and Montana, with a total of 4030 households sampled; 685 households were sampled in Climate Zone 2. Informational data are presented in 54 tables. (MCW)

  5. 32 CFR Appendix A to Part 110 - Climatic Zones Used To Determine Rates of Commutation Allowance

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Virginia 42. Wisconsin 43. Wyoming The climate zones listed above are to be used as a guide to determine... commanders may request a zone change by submitting evidence to the Major Command of the appropriate Military...

  6. 32 CFR Appendix A to Part 110 - Climatic Zones Used To Determine Rates of Commutation Allowance

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Virginia 42. Wisconsin 43. Wyoming The climate zones listed above are to be used as a guide to determine... commanders may request a zone change by submitting evidence to the Major Command of the appropriate Military...

  7. 32 CFR Appendix A to Part 110 - Climatic Zones Used To Determine Rates of Commutation Allowance

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Virginia 42. Wisconsin 43. Wyoming The climate zones listed above are to be used as a guide to determine... commanders may request a zone change by submitting evidence to the Major Command of the appropriate Military...

  8. 32 CFR Appendix A to Part 110 - Climatic Zones Used To Determine Rates of Commutation Allowance

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Virginia 42. Wisconsin 43. Wyoming The climate zones listed above are to be used as a guide to determine... commanders may request a zone change by submitting evidence to the Major Command of the appropriate Military...

  9. 32 CFR Appendix A to Part 110 - Climatic Zones Used To Determine Rates of Commutation Allowance

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Virginia 42. Wisconsin 43. Wyoming The climate zones listed above are to be used as a guide to determine... commanders may request a zone change by submitting evidence to the Major Command of the appropriate Military...

  10. Distribution and management of cattle in relation to climatic zones within North America

    SciTech Connect

    Bull, L.S.

    1986-07-01

    This paper reviews the distribution of cattle within the climatic zones of the US and describes the prevalent management systems used in each zone. The complexity of elevation, rainfall, and temperature within each zone requires much closer evaluation. The practicing veterinarian or animal husbandman must evaluate the specific climatic conditions prevailing on the farm or ranch in question and integrate the components of that climate into the management or health practices to be recommended.

  11. The frontal branch of the facial nerve: can we define a safety zone?

    PubMed

    de Bonnecaze, G; Chaput, B; Filleron, T; Al Hawat, A; Vergez, S; Chaynes, P

    2015-07-01

    The temporal branch of the facial nerve, a particularly important branch in facial expression, is commonly exposed to surgical trauma. The frontal branch is the most important branch of the temporal branch in the clinical point of view. However, it does not really define in the international nomenclature. The objective of this study was to clearly identify this branch, to perform a cartography of the crossing areas of this branch; and therefore to define statistically a zone of safety within the fronto-temporal region. We used 12 fresh cadavers to perform 24 facial nerve dissections. After the identification of the facial nerve, the branches of the temporofacial trunk were identified, dissected and followed till their penetration. We measured the relationship of the frontal branch with the zygomatic arch, temporal vessels and lateral border of the orbit. We conducted a statistical study to assess the risk of injury of this branch within the temporal region. We observed an important variability in the distribution of this branch in the temporal region. We defined three zones of decreasing safety at the level of three interest landmarks: at the level of the inferior part of the zygomatic arch, we estimated an elevated risk of nerve injury (>85%) from 22.6 to 26.06 mm in front of the tragus; at the level of the superior part of the zygomatic arch, we estimated an elevated risk of nerve injury (>85%) from 27.46 to 30.43 mm in front of the tragus; at the level of the lateral border of the orbit, we estimated an elevated risk of nerve injury (>85%) from 16.20 to 19.17 mm behind this landmark. There exists no real area of anatomical safety in the temporal region. It seems, however, possible to define areas of relative safety that would be of great help for the surgeon or the morphologist wishing to approach pathologies of this region.

  12. Sensitivity of potential evapotranspiration to changes in climate variables for different Australian climatic zones

    NASA Astrophysics Data System (ADS)

    Guo, Danlu; Westra, Seth; Maier, Holger R.

    2017-04-01

    Assessing the factors that have an impact on potential evapotranspiration (PET) sensitivity to changes in different climate variables is critical to understanding the possible implications of climatic changes on the catchment water balance. Using a global sensitivity analysis, this study assessed the implications of baseline climate conditions on the sensitivity of PET to a large range of plausible changes in temperature (T), relative humidity (RH), solar radiation (Rs) and wind speed (uz). The analysis was conducted at 30 Australian locations representing different climatic zones, using the Penman-Monteith and Priestley-Taylor PET models. Results from both models suggest that the baseline climate can have a substantial impact on overall PET sensitivity. In particular, approximately 2-fold greater changes in PET were observed in cool-climate energy-limited locations compared to other locations in Australia, indicating the potential for elevated water loss as a result of increasing actual evapotranspiration (AET) in these locations. The two PET models consistently indicated temperature to be the most important variable for PET, but showed large differences in the relative importance of the remaining climate variables. In particular for the Penman-Monteith model, wind and relative humidity were the second-most important variables for dry and humid catchments, respectively, whereas for the Priestley-Taylor model solar radiation was the second-most important variable, with the greatest influence in warmer catchments. This information can be useful to inform the selection of suitable PET models to estimate future PET for different climate conditions, providing evidence on both the structural plausibility and input uncertainty for the alternative models.

  13. A study of the impacts of climate change scenarios on the plant hardiness zones of Albania

    USDA-ARS?s Scientific Manuscript database

    Maps of plant hardiness zones are useful tools for determining the extreme limits for the survival of plants. Exploration of projected climate change effects on hardiness zones can help identify areas most affected by climate change. Such studies are important in areas with high risks related to cli...

  14. Defining the worst case scenario for the Makran Subduction Zone: the 1008 AD tsunami

    NASA Astrophysics Data System (ADS)

    Hoffmann, Goesta

    2016-04-01

    correlated to the 1008 AD earthquake and tsunami inundation. The boulder deposits as well as the archaeological remains testify for a maximum tsunami runup of 15m, exceeding by far the inundation as observed in 1945. We define this as the worst case scenario for the Makran Subduction Zone. However, the return period is rather large (>500 years).

  15. The climate of Carpathian Region in the 20th century based on the original and modified Holdridge life zone system

    NASA Astrophysics Data System (ADS)

    Szelepcsényi, Zoltán; Breuer, Hajnalka; Sümegi, Pál

    2014-09-01

    The Holdridge life zone system has already been used a number of times for analysing the effects of climate change on vegetation. But a criticism against the method was formulated that it cannot interpret the ecotones (e.g. forest steppe). Thus, in this paper transitional life zones were also determined in the model. Then, both the original and modified life zone systems were applied for the climatic fields of database CRU TS 1.2. Life zone maps were defined in the Carpathian Region (43.5-50.5° N, 15.5-28° E) for each of five 20-year periods between 1901 and 2000. We estimated correctness of the result maps with another vegetation map using Cohen's Kappa statistic. Finally, temporal changes in horizontal and vertical distribution of life zones were investigated. The coverage of boreal region decreased with 59.46% during the last century, while the warm temperate region became almost two and a half larger (257.36%). The mean centres of those life zones, which were not related to mountains, shifted northward during the investigation period. In case of the most abundant life zone types, the average distribution elevation increased. Using the modified model, the potential distribution of forest steppe could be also identified.

  16. 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.

  17. Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas, Observations and Modelling

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Wave Climate and Wave Mixing in the Marginal Ice Zones of... climate is available over the entire period of existence of the marginal Arctic ice zones. Figure 1. Altimeter missions by Agency (1985-2015...to obtain the wave climate in the Arctic and its trends. Trends are obtained for mean and , as well as for their 90th and 99th percentiles, over

  18. Application of Maxent Multivariate Analysis to Define Reptile Species Distributions and Changes Related to Climate Change

    DTIC Science & Technology

    2016-06-01

    ER D C/ CE RL T R- 16 -6 Base Facilities Environmental Quality Application of Maxent Multivariate Analysis to Define Reptile Species ...Define Reptile Species Distributions and Changes Related to Climate Change Robert C. Lozar and James D. Westervelt Construction Engineering Research...ii Abstract The maximum entropy (Maxent) statistical technique was applied to de- termine the habitat extent of seven reptile species and to

  19. Screening high oleaginous Chlorella strains from different climate zones.

    PubMed

    Xu, Jin; Hu, Hanhua

    2013-09-01

    In outdoor cultivation, screening strains adapted to a wide temperature range or suitable strains for different environmental temperatures is of great importance. In this study, triacylglycerol (TAG) content of 23 oil-producing Chlorella strains from different climate zones were analyzed by thin layer chromatography. Four selected Chlorella strains (NJ-18, NJ-7, NMX35N and NMX139N) with rather high TAG content had higher total lipid content compared with Chlorella vulgaris SAG 211-11b. In particular, NJ-18 displayed the highest TAG productivity among the four high oil-producing Chlorella strains. Accumulation of TAGs in strain NMX35N changed a little from 30 to 40°C, showing a desirable characteristic of accumulating TAGs at high temperatures. Our results demonstrated that NJ-18 and NMX35N had suitable fatty acid profiles and good adaption to low and high temperatures respectively. Therefore, cultivation of the two Chlorella strains together might be a good option for economic biodiesel production during the whole seasons of the year.

  20. Transcriptional programs in transient embryonic zones of the cerebral cortex defined by high-resolution mRNA sequencing

    PubMed Central

    Ayoub, Albert E.; Oh, Sunghee; Xie, Yanhua; Leng, Jing; Cotney, Justin; Dominguez, Martin H.; Noonan, James P.; Rakic, Pasko

    2011-01-01

    Characterizing the genetic programs that specify development and evolution of the cerebral cortex is a central challenge in neuroscience. Stem cells in the transient embryonic ventricular and subventricular zones generate neurons that migrate across the intermediate zone to the overlying cortical plate, where they differentiate and form the neocortex. It is clear that not one but a multitude of molecular pathways are necessary to progress through each cellular milestone, yet the underlying transcriptional programs remain unknown. Here, we apply differential transcriptome analysis on microscopically isolated cell populations, to define five transcriptional programs that represent each transient embryonic zone and the progression between these zones. The five transcriptional programs contain largely uncharacterized genes in addition to transcripts necessary for stem cell maintenance, neurogenesis, migration, and differentiation. Additionally, we found intergenic transcriptionally active regions that possibly encode unique zone-specific transcripts. Finally, we present a high-resolution transcriptome map of transient zones in the embryonic mouse forebrain. PMID:21873192

  1. Progress in Australian dendroclimatology: Identifying growth limiting factors in four climate zones.

    PubMed

    Haines, Heather A; Olley, Jon M; Kemp, Justine; English, Nathan B

    2016-12-01

    Dendroclimatology can be used to better understand past climate in regions such as Australia where instrumental and historical climate records are sparse and rarely extend beyond 100years. Here we review 36 Australian dendroclimatic studies which cover the four major climate zones of Australia; temperate, arid, subtropical and tropical. We show that all of these zones contain tree and shrub species which have the potential to provide high quality records of past climate. Despite this potential only four dendroclimatic reconstructions have been published for Australia, one from each of the climate zones: A 3592year temperature record for the SE-temperate zone, a 350year rainfall record for the Western arid zone, a 140year rainfall record for the northern tropics and a 146year rainfall record for SE-subtropics. We report on the spatial distribution of tree-ring studies, the environmental variables identified as limiting tree growth in each study, and identify the key challenges in using tree-ring records for climate reconstruction in Australia. We show that many Australian species have yet to be tested for dendroclimatological potential, and that the application of newer techniques including isotopic analysis, carbon dating, wood density measurements, and anatomical analysis, combined with traditional ring-width measurements should enable more species in each of the climate zones to be used, and long-term climate records to be developed across the entire continent. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Prevalence of esophageal eosinophilia varies by climate zone in the United States

    PubMed Central

    Hurrell, Jennifer M; Genta, Robert M.; Dellon, Evan S.

    2015-01-01

    Objectives The epidemiology of eosinophilic esophagitis (EoE) is rapidly evolving, and differences in climate could impact the prevalence of EoE. We aimed to examine the association between esophageal eosinophilia and climate zones in the U.S. Methods This was a cross-sectional study of esophageal biopsies from 2008 to 2010 in a large U.S. pathology database. Cases were patients with esophageal eosinophilia; controls had normal esophageal biopsies. A Köppen-Geiger (K-G) climate class was assigned to each patient, and the association between case-control status and the main K-G climate type (tropical, arid, temperate, or cold) was assessed. Results A total of 233,649 patients were included, 71,948 (30.8%) with normal esophageal biopsies and 9,995 (4.3%) with esophageal eosinophilia. Using the temperate zone as the referent and after multivariable analysis, the odds of esophageal eosinophilia were highest in the cold climate zone (OR = 1.39, 95% CI: 1.34-1.47), compared to the tropical zone (OR = 0.87; 95% CI: 0.71-10.8) and the arid zone (OR = 1.27; 95% CI: 1.19-1.36). Increased likelihood of EoE was also associated with increasing odds of being in the cold climate zone. Compared to patients with normal esophageal biopsies, patients with dysphagia, a clinical suspicion of EoE, no reflux or Barrett’s esophagus, esophageal eosinophilia, and eosinophilic microabscesses had the highest adjusted odds of being in a cold climate zone (OR 2.02; 1.78-2.28). Conclusions Esophageal eosinophilia differs significantly between K-G climate zones, with the highest prevalence in the cold and arid zones. Geographic and climate patterns may help identify candidate antigens characteristic to high-prevalence areas to be targeted for future investigation. PMID:22310220

  3. Demand Shifting with Thermal Mass in Large Commercial Buildings in a California Hot Climate Zone

    SciTech Connect

    Xu, Peng; Yin, Rongxin; Brown, Carrie; Kim, DongEun

    2009-06-01

    The potential for using building thermal mass for load shifting and peak energy demand reduction has been demonstrated in a number of simulation, laboratory, and field studies. Previous Lawrence Berkeley National Laboratory research has demonstrated that the approach is very effective in cool and moderately warm climate conditions (California Climate Zones 2-4). However, this method had not been tested in hotter climate zones. This project studied the potential of pre-cooling the building early in the morning and increasing temperature setpoints during peak hours to reduce cooling-related demand in two typical office buildings in hotter California climates ? one in Visalia (CEC Climate Zone 13) and the other in San Bernardino (CEC Climate Zone 10). The conclusion of the work to date is that pre-cooling in hotter climates has similar potential to that seen previously in cool and moderate climates. All other factors being equal, results to date indicate that pre-cooling increases the depth (kW) and duration (kWh) of the possible demand shed of a given building. The effectiveness of night pre-cooling in typical office building under hot weather conditions is very limited. However, night pre-cooling is helpful for office buildings with an undersized HVAC system. Further work is required to duplicate the tests in other typical buildings and in other hot climate zones and prove that pre-cooling is truly effective.

  4. The effects of climate change on heating energy consumption of office buildings in different climate zones in China

    NASA Astrophysics Data System (ADS)

    Meng, Fanchao; Li, Mingcai; Cao, Jingfu; Li, Ji; Xiong, Mingming; Feng, Xiaomei; Ren, Guoyu

    2017-06-01

    Climate plays an important role in heating energy consumption owing to the direct relationship between space heating and changes in meteorological conditions. To quantify the impact, the Transient System Simulation Program software was used to simulate the heating loads of office buildings in Harbin, Tianjin, and Shanghai, representing three major climate zones (i.e., severe cold, cold, and hot summer and cold winter climate zones) in China during 1961-2010. Stepwise multiple linear regression was performed to determine the key climatic parameters influencing heating energy consumption. The results showed that dry bulb temperature (DBT) is the dominant climatic parameter affecting building heating loads in all three climate zones across China during the heating period at daily, monthly, and yearly scales (R 2 ≥ 0.86). With the continuous warming climate in winter over the past 50 years, heating loads decreased by 14.2, 7.2, and 7.1 W/m2 in Harbin, Tianjin, and Shanghai, respectively, indicating that the decreasing rate is more apparent in severe cold climate zone. When the DBT increases by 1 °C, the heating loads decrease by 253.1 W/m2 in Harbin, 177.2 W/m2 in Tianjin, and 126.4 W/m2 in Shanghai. These results suggest that the heating energy consumption can be well predicted by the regression models at different temporal scales in different climate conditions owing to the high determination coefficients. In addition, a greater decrease in heating energy consumption in northern severe cold and cold climate zones may efficiently promote the energy saving in these areas with high energy consumption for heating. Particularly, the likely future increase in temperatures should be considered in improving building energy efficiency.

  5. Defining and Measuring Safety Climate: A Review of the Construction Industry Literature.

    PubMed

    Schwatka, Natalie V; Hecker, Steven; Goldenhar, Linda M

    2016-06-01

    Safety climate measurements can be used to proactively assess an organization's effectiveness in identifying and remediating work-related hazards, thereby reducing or preventing work-related ill health and injury. This review article focuses on construction-specific articles that developed and/or measured safety climate, assessed safety climate's relationship with other safety and health performance indicators, and/or used safety climate measures to evaluate interventions targeting one or more indicators of safety climate. Fifty-six articles met our inclusion criteria, 80% of which were published after 2008. Our findings demonstrate that researchers commonly defined safety climate as perception based, but the object of those perceptions varies widely. Within the wide range of indicators used to measure safety climate, safety policies, procedures, and practices were the most common, followed by general management commitment to safety. The most frequently used indicators should and do reflect that the prevention of work-related ill health and injury depends on both organizational and employee actions. Safety climate scores were commonly compared between groups (e.g. management and workers, different trades), and often correlated with subjective measures of safety behavior rather than measures of ill health or objective safety and health outcomes. Despite the observed limitations of current research, safety climate has been promised as a useful feature of research and practice activities to prevent work-related ill health and injury. Safety climate survey data can reveal gaps between management and employee perceptions, or between espoused and enacted policies, and trigger communication and action to narrow those gaps. The validation of safety climate with safety and health performance data offers the potential for using safety climate measures as a leading indicator of performance. We discuss these findings in relation to the related concept of safety culture and

  6. Integration of climatic indices in an objective probabilistic model for establishing and mapping viticultural climatic zones in a region

    NASA Astrophysics Data System (ADS)

    Moral, Francisco J.; Rebollo, Francisco J.; Paniagua, Luis L.; García, Abelardo; Honorio, Fulgencio

    2016-05-01

    Different climatic indices have been proposed to determine the wine suitability in a region. Some of them are related to the air temperature, but the hydric component of climate should also be considered which, in turn, is influenced by the precipitation during the different stages of the grapevine growing and ripening periods. In this study, we propose using the information obtained from ten climatic indices [heliothermal index (HI), cool night index (CI), dryness index (DI), growing season temperature (GST), the Winkler index (WI), September mean thermal amplitude (MTA), annual precipitation (AP), precipitation during flowering (PDF), precipitation before flowering (PBF), and summer precipitation (SP)] as inputs in an objective and probabilistic model, the Rasch model, with the aim of integrating the individual effects of them, obtaining the climate data that summarize all main climatic indices, which could influence on wine suitability from a climate viewpoint, and utilizing the Rasch measures to generate homogeneous climatic zones. The use of the Rasch model to estimate viticultural climatic suitability constitutes a new application of great practical importance, enabling to rationally determine locations in a region where high viticultural potential exists and establishing a ranking of the climatic indices which exerts an important influence on wine suitability in a region. Furthermore, from the measures of viticultural climatic suitability at some locations, estimates can be computed using a geostatistical algorithm, and these estimates can be utilized to map viticultural climatic zones in a region. To illustrate the process, an application to Extremadura, southwestern Spain, is shown.

  7. Climate change effects on reference crop evapotranspiration across different climatic zones of China during 1956-2015

    NASA Astrophysics Data System (ADS)

    Fan, Junliang; Wu, Lifeng; Zhang, Fucang; Xiang, Youzhen; Zheng, Jing

    2016-11-01

    Global climate change has been an increasing challenge to agricultural ecosystems, which will significantly affect the reference crop evapotranspiration (ET0) and subsequently crop water requirements. In this study, the temporal trends and magnitudes of key climatic variables and the accompanying effects on ET0 during 1956-2015 were evaluated at 200 meteorological stations across the temperate continental zone (TCZ), temperate monsoon zone (TMZ), mountain plateau zone (MPZ), and subtropical monsoon zone (SMZ) of China. Results show that maximum and minimum temperatures have increased significantly over the past 60 years, whilst relative humidity, wind speed and sunshine hour exhibited significant decreasing trends across all climatic zones. The overall decreasing trends in annual ET0 were more pronounced than the increasing trends, whereas more increasing trends were found in spring and winter. Abrupt changes for climatic variables and ET0 series were detected in 1990s in the MPZ, while in 1980s in the other climatic zones mainly due to the aggregated emission of greenhouse gases and air pollution from energy consumption in recent decades. Relative humidity was the most sensitive climatic variable in all climatic zones except for the MPZ where ET0 was most sensitive to sunshine hour. However, ET0 had different responses to changing climatic variables in different regions and climatic conditions. The negative contribution of wind speed to the decrease in ET0 was greater than the other climatic variables in the TCZ and the TMZ, whilst the significant increase in minimum temperature and the decrease in sunshine hour contributed most to increasing ET0 in the MPZ and to decreasing ET0 in the SMZ, respectively. Although ET0 displayed a generally decreasing trend during 1956-2015, there was a significantly increasing trend from 1985 to 2015 across China except for the SMZ, especially in the arid and semi-arid zones of China during dry seasons (spring and winter). This may

  8. Variations of Soil Microbial Community Structures Beneath Broadleaved Forest Trees in Temperate and Subtropical Climate Zones.

    PubMed

    Yang, Sihang; Zhang, Yuguang; Cong, Jing; Wang, Mengmeng; Zhao, Mengxin; Lu, Hui; Xie, Changyi; Yang, Caiyun; Yuan, Tong; Li, Diqiang; Zhou, Jizhong; Gu, Baohua; Yang, Yunfeng

    2017-01-01

    Global warming has shifted climate zones poleward or upward. However, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate). Although plant species richness decreased with latitudes, the microbial taxonomic α-diversity increased with latitudes, concomitant with increases in soil total and available nitrogen and phosphorus contents. Phylogenetic NRI (Net Relatedness Index) values increased from -0.718 in temperate zone (WLM) to 1.042 in subtropical zone (SNJ), showing a shift from over dispersion to clustering likely caused by environmental filtering such as low pH and nutrients. Similarly, taxonomy-based association networks of subtropical forest samples were larger and tighter, suggesting clustering. In contrast, functional α-diversity was similar among three forests, but functional gene networks of the FNM forest significantly (P < 0.050) differed from the others. A significant correlation (R = 0.616, P < 0.001) between taxonomic and functional β-diversity was observed only in the FNM forest, suggesting low functional redundancy at the border of climate zones. Using a strategy of space-for-time substitution, we predict that poleward climate range shift will lead to decreased microbial taxonomic α-diversities in broadleaved forest.

  9. Variations of Soil Microbial Community Structures Beneath Broadleaved Forest Trees in Temperate and Subtropical Climate Zones

    PubMed Central

    Yang, Sihang; Zhang, Yuguang; Cong, Jing; Wang, Mengmeng; Zhao, Mengxin; Lu, Hui; Xie, Changyi; Yang, Caiyun; Yuan, Tong; Li, Diqiang; Zhou, Jizhong; Gu, Baohua; Yang, Yunfeng

    2017-01-01

    Global warming has shifted climate zones poleward or upward. However, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate). Although plant species richness decreased with latitudes, the microbial taxonomic α-diversity increased with latitudes, concomitant with increases in soil total and available nitrogen and phosphorus contents. Phylogenetic NRI (Net Relatedness Index) values increased from -0.718 in temperate zone (WLM) to 1.042 in subtropical zone (SNJ), showing a shift from over dispersion to clustering likely caused by environmental filtering such as low pH and nutrients. Similarly, taxonomy-based association networks of subtropical forest samples were larger and tighter, suggesting clustering. In contrast, functional α-diversity was similar among three forests, but functional gene networks of the FNM forest significantly (P < 0.050) differed from the others. A significant correlation (R = 0.616, P < 0.001) between taxonomic and functional β-diversity was observed only in the FNM forest, suggesting low functional redundancy at the border of climate zones. Using a strategy of space-for-time substitution, we predict that poleward climate range shift will lead to decreased microbial taxonomic α-diversities in broadleaved forest. PMID:28239373

  10. Climatic zoning for the calculation of the thermal demand of buildings in Extremadura (Spain)

    NASA Astrophysics Data System (ADS)

    Moral, Francisco J.; Pulido, Elena; Ruíz, Antonio; López, Fernando

    2017-08-01

    The present work reports on a methodology to assess the climatic severity of a particular geographic region as compared to specific information available in the current regulations. The viability for each of the 387 municipalities in the Autonomous Community of Extremadura (Spain) is analysed, making a distinction between those with reliable climate reports and those for which no such information is available. In the case study, although the weather conditions in Extremadura are quite homogeneous according to the Spanish Technical Building Code (STBC 2015) classification and most areas are associated to zone C4 (soft winters and hot summers), the southern area in the region is associated to zone D1, similar to the north of Spain, where winters and summers are cool, which does not coincide with the actual climate in the south of Extremadura. The general climatic homogeneity in Extremadura was also highlighted with the new procedure, predominating zone C4, but unexpected or unreal climatic zoning was not generated, giving place to a consistent spatial distribution of zones throughout the region. Consequently, the proposed method allows a more accurate climatic zoning of any region in agreement with the Spanish legislation on energy efficiency in buildings, which would enhance the setting of thermal demand rates according to the actual climatic characterisation of the area in which a particular municipality is located.

  11. Climatic zoning for the calculation of the thermal demand of buildings in Extremadura (Spain)

    NASA Astrophysics Data System (ADS)

    Moral, Francisco J.; Pulido, Elena; Ruíz, Antonio; López, Fernando

    2016-05-01

    The present work reports on a methodology to assess the climatic severity of a particular geographic region as compared to specific information available in the current regulations. The viability for each of the 387 municipalities in the Autonomous Community of Extremadura (Spain) is analysed, making a distinction between those with reliable climate reports and those for which no such information is available. In the case study, although the weather conditions in Extremadura are quite homogeneous according to the Spanish Technical Building Code (STBC 2015) classification and most areas are associated to zone C4 (soft winters and hot summers), the southern area in the region is associated to zone D1, similar to the north of Spain, where winters and summers are cool, which does not coincide with the actual climate in the south of Extremadura. The general climatic homogeneity in Extremadura was also highlighted with the new procedure, predominating zone C4, but unexpected or unreal climatic zoning was not generated, giving place to a consistent spatial distribution of zones throughout the region. Consequently, the proposed method allows a more accurate climatic zoning of any region in agreement with the Spanish legislation on energy efficiency in buildings, which would enhance the setting of thermal demand rates according to the actual climatic characterisation of the area in which a particular municipality is located.

  12. Variations of soil microbial community structures beneath broadleaved forest trees in temperate and subtropical climate zones

    DOE PAGES

    Yang, Sihang; Zhang, Yuguang; Cong, Jing; ...

    2017-02-10

    Global warming has shifted climate zones poleward or upward. Furthermore, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate). Although plant species richness decreased with latitudes, the microbial taxonomic α-diversity increased with latitudes, concomitant with increases in soil total and available nitrogen and phosphorus contents. Phylogenetic NRImore » (Net Relatedness Index) values increased from 0.718 in temperate zone (WLM) to 1.042 in subtropical zone (SNJ), showing a shift from over dispersion to clustering likely caused by environmental filtering such as low pH and nutrients. Similarly, taxonomybased association networks of subtropical forest samples were larger and tighter, suggesting clustering. In contrast, functional α-diversity was similar among three forests, but functional gene networks of the FNM forest significantly (P < 0.050) differed from the others. A significant correlation (R = 0.616, P < 0.001) between taxonomic and functional β-diversity was observed only in the FNM forest, suggesting low functional redundancy at the border of climate zones. Using a strategy of space-fortime substitution, we predict that poleward climate range shift will lead to decreased microbial taxonomic α-diversities in broadleaved forest.« less

  13. Dermatophytosis among Schoolchildren in Three Eco-climatic Zones of Mali.

    PubMed

    Coulibaly, Oumar; Kone, Abdoulaye K; Niaré-Doumbo, Safiatou; Goïta, Siaka; Gaudart, Jean; Djimdé, Abdoulaye A; Piarroux, Renaud; Doumbo, Ogobara K; Thera, Mahamadou A; Ranque, Stéphane

    2016-04-01

    Dermatophytosis, and particularly the subtype tinea capitis, is common among African children; however, the risk factors associated with this condition are poorly understood. To describe the epidemiology of dermatophytosis in distinct eco-climatic zones, three cross-sectional surveys were conducted in public primary schools located in the Sahelian, Sudanian and Sudano-Guinean eco-climatic zones in Mali. Among 590 children (average age 9.7 years) the overall clinical prevalence of tinea capitis was 39.3%. Tinea capitis prevalence was 59.5% in the Sudano-Guinean zone, 41.6% in the Sudanian zone and 17% in the Sahelian eco-climatic zone. Microsporum audouinii was isolated primarily from large and/or microsporic lesions. Trichophyton soudanense was primarily isolated from trichophytic lesions. Based on the multivariate analysis, tinea capitis was independently associated with male gender (OR = 2.51, 95%CI [1.74-3.61], P<10(-4)) and residing in the Sudano-Guinean eco-climatic zone (OR = 7.45, 95%CI [4.63-11.99], P<10(-4)). Two anthropophilic dermatophytes species, Trichophyton soudanense and Microsporum audouinii, were the most frequent species associated with tinea capitis among primary schoolchildren in Mali. Tinea capitis risk increased with increasing climate humidity in this relatively homogenous schoolchild population in Mali, which suggests a significant role of climatic factors in the epidemiology of dermatophytosis.

  14. Dermatophytosis among Schoolchildren in Three Eco-climatic Zones of Mali

    PubMed Central

    Coulibaly, Oumar; Kone, Abdoulaye K.; Niaré-Doumbo, Safiatou; Goïta, Siaka; Gaudart, Jean; Djimdé, Abdoulaye A.; Piarroux, Renaud; Doumbo, Ogobara K.; Thera, Mahamadou A.

    2016-01-01

    Background Dermatophytosis, and particularly the subtype tinea capitis, is common among African children; however, the risk factors associated with this condition are poorly understood. To describe the epidemiology of dermatophytosis in distinct eco-climatic zones, three cross-sectional surveys were conducted in public primary schools located in the Sahelian, Sudanian and Sudano-Guinean eco-climatic zones in Mali. Principal Findings Among 590 children (average age 9.7 years) the overall clinical prevalence of tinea capitis was 39.3%. Tinea capitis prevalence was 59.5% in the Sudano-Guinean zone, 41.6% in the Sudanian zone and 17% in the Sahelian eco-climatic zone. Microsporum audouinii was isolated primarily from large and/or microsporic lesions. Trichophyton soudanense was primarily isolated from trichophytic lesions. Based on the multivariate analysis, tinea capitis was independently associated with male gender (OR = 2.51, 95%CI [1.74–3.61], P<10−4) and residing in the Sudano-Guinean eco-climatic zone (OR = 7.45, 95%CI [4.63–11.99], P<10−4). Two anthropophilic dermatophytes species, Trichophyton soudanense and Microsporum audouinii, were the most frequent species associated with tinea capitis among primary schoolchildren in Mali. Conclusions Tinea capitis risk increased with increasing climate humidity in this relatively homogenous schoolchild population in Mali, which suggests a significant role of climatic factors in the epidemiology of dermatophytosis. PMID:27124571

  15. Lumpy skin disease in Ethiopia: seroprevalence study across different agro-climate zones.

    PubMed

    Gari, G; Grosbois, V; Waret-Szkuta, A; Babiuk, S; Jacquiet, P; Roger, F

    2012-08-01

    A cross-sectional study was conducted to estimate the seroprevalence of lumpy skin disease (LSD) in the different agro-climatic zones prevailing in Ethiopia. A total of 2368 serum samples were collected from 42 kebeles located in 15 districts and tested using indirect fluorescent antibody test (IFAT) and virus neutralization test (VNT). The herd and animal true LSD serological prevalence were estimated in each agro-climate zone using a Bayesian model. The intra-cluster correlation coefficient (ICC) was evaluated using a random-effect model. According to the serological prevalence estimations, LSD affected differently the three agro-climatic zones considered. Herd level seroprevalence was higher in the midland agro-climate zone 64% (95% CI: 53-74) as compared to the highland 26% (95% CI: 17-36) and the lowland 50% (95% CI: 40-60) agro-climates. Animal level seroprevalence in infected herds was also higher in the midland agro-climate zone 31% (95% CI: 24-40) than in the highland and lowland zones (24% (95% CI: 18-31) and 23% (95% CI: 18-29), respectively). Higher ICC value in the highland agro-climate zone implies that increased sample sizes should be particularly required for this zone in future studies to estimate LSD prevalence or incidence with a desired precision level. This seroprevalence study also suggests that the prevalence of LSD infection in Ethiopia is higher than what has been previously reported. In the light of these updated estimations, we discuss options to trigger appropriate control measures in the future.

  16. 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.

  17. UNSATURATED ZONE CALCITE 813C EVIDENCE OF SOUTHERN NEVADA CLIMATES DURING THE PAST 9 MILLION YEARS

    SciTech Connect

    JOSEPH F. WHELAN AND RICHARD J. MOSCATI

    1998-01-26

    Yucca Mountain, Nevada, is presently the object of intense study as a potential permanent repository for the Nation's high-level radioactive wastes. The mountain consists of a thick sequence of volcanic tuffs in which the depth to the water table ranges from 500 to 700 meters below the land surface. This thick unsaturated zone (UZ), which would host the projected repository, coupled with the present-day arid to semi-arid environment, is considered a positive argument for the site. Evaluation of the site includes defining the relationship between climate variability, as the input function or driver of site- and regional-scale ground-water flow, and the possible transport and release of radionuclides. Secondary calcite and opal have been deposited in the UZ by meteoric waters that infiltrated through overlying soils and percolated through the tuffs. The oxygen isotopic composition ({delta}{sup 18}O values) of these minerals reflect contemporaneous meteoric waters and the {delta}{sup 13}C values reflect soil organic matter, and hence the resident plant community, at the time of infiltration (Whelan et al., 1994). Recent U/Pb age determinations of opal in these occurrences allows the {delta}{sup 13}C values of associated calcite to be used to reconstruct general climate variations during the past 9 M.y.

  18. Can we define the Impact of Climate Change on Ljubljansko polje Aquifer

    NASA Astrophysics Data System (ADS)

    Bracic Zeleznik, B.; Cencur Curk, B.

    2009-04-01

    and define the "natural" and "anthropological" Climate Change patterns.

  19. Morphological Adaptations for Digging and Climate-Impacted Soil Properties Define Pocket Gopher (Thomomys spp.) Distributions

    PubMed Central

    Marcy, Ariel E.; Fendorf, Scott; Patton, James L.; Hadly, Elizabeth A.

    2013-01-01

    Species ranges are mediated by physiology, environmental factors, and competition with other organisms. The allopatric distribution of five species of northern Californian pocket gophers (Thomomys spp.) is hypothesized to result from competitive exclusion. The five species in this environmentally heterogeneous region separate into two subgenera, Thomomys or Megascapheus, which have divergent digging styles. While all pocket gophers dig with their claws, the tooth-digging adaptations of subgenus Megascapheus allow access to harder soils and climate-protected depths. In a Northern Californian locality, replacement of subgenus Thomomys with subgenus Megascapheus occurred gradually during the Pleistocene-Holocene transition. Concurrent climate change over this transition suggests that environmental factors – in addition to soil – define pocket gopher distributional limits. Here we show 1) that all pocket gophers occupy the subset of less energetically costly soils and 2) that subgenera sort by percent soil clay, bulk density, and shrink-swell capacity (a mineralogical attribute). While clay and bulk density (without major perturbations) stay constant over decades to millennia, low precipitation and high temperatures can cause shrink-swell clays to crack and harden within days. The strong yet underappreciated interaction between soil and moisture on the distribution of vertebrates is rarely considered when projecting species responses to climatic change. Furthermore, increased precipitation alters the weathering processes that create shrink-swell minerals. Two projected outcomes of ongoing climate change—higher temperatures and precipitation—will dramatically impact hardness of soil with shrink-swell minerals. Current climate models do not include factors controlling soil hardness, despite its impact on all organisms that depend on a stable soil structure. PMID:23717675

  20. Weathering of the New Albany Shale, Kentucky, USA: I. Weathering zones defined by mineralogy and major-element composition

    USGS Publications Warehouse

    Tuttle, M.L.W.; Breit, G.N.

    2009-01-01

    Comprehensive understanding of chemical and mineralogical changes induced by weathering is valuable information when considering the supply of nutrients and toxic elements from rocks. Here minerals that release and fix major elements during progressive weathering of a bed of Devonian New Albany Shale in eastern Kentucky are documented. Samples were collected from unweathered core (parent shale) and across an outcrop excavated into a hillside 40 year prior to sampling. Quantitative X-ray diffraction mineralogical data record progressive shale alteration across the outcrop. Mineral compositional changes reflect subtle alteration processes such as incongruent dissolution and cation exchange. Altered primary minerals include K-feldspars, plagioclase, calcite, pyrite, and chlorite. Secondary minerals include jarosite, gypsum, goethite, amorphous Fe(III) oxides and Fe(II)-Al sulfate salt (efflorescence). The mineralogy in weathered shale defines four weathered intervals on the outcrop-Zones A-C and soil. Alteration of the weakly weathered shale (Zone A) is attributed to the 40-a exposure of the shale. In this zone, pyrite oxidization produces acid that dissolves calcite and attacks chlorite, forming gypsum, jarosite, and minor efflorescent salt. The pre-excavation, active weathering front (Zone B) is where complete pyrite oxidation and alteration of feldspar and organic matter result in increased permeability. Acidic weathering solutions seep through the permeable shale and evaporate on the surface forming abundant efflorescent salt, jarosite and minor goethite. Intensely weathered shale (Zone C) is depleted in feldspars, chlorite, gypsum, jarosite and efflorescent salts, but has retained much of its primary quartz, illite and illite-smectite. Goethite and amorphous FE(III) oxides increase due to hydrolysis of jarosite. Enhanced permeability in this zone is due to a 14% loss of the original mass in parent shale. Denudation rates suggest that characteristics of Zone C

  1. Bistability of the climate around the habitable zone: A thermodynamic investigation

    NASA Astrophysics Data System (ADS)

    Boschi, Robert; Lucarini, Valerio; Pascale, Salvatore

    2013-11-01

    The goal of this paper is to explore the potential multistability of the climate for a planet around the habitable zone. We apply our methodology to the Earth system, but our investigation has more general relevance. A thorough investigation of the thermodynamics of the climate system is performed for very diverse conditions of energy input and infrared atmosphere opacity. Using PlaSim, an Earth-like general circulation model, the solar constant S∗ is modulated between 1160 and 1510 W m-2 and the CO2 concentration, [CO2], between 90 and 2880 ppm. It is observed that in such a parameter range the climate is bistable, i.e. there are two coexisting attractors, one characterised by warm, moist climates (W) and one by completely frozen sea surface (Snowball Earth, SB). The tipping points of both the transitions (W → SB and SB →W) are located along straight lines in the (S∗, log[CO2]) space. The dynamical and thermodynamical properties - energy fluxes, Lorenz energy cycle, Carnot efficiency, material entropy production - of the W and SB states are very different: W states are dominated by the hydrological cycle and latent heat is prominent in the material entropy production; the SB states are eminently dry climates where heat transport is realised through sensible heat fluxes and entropy mostly generated by dissipation of kinetic energy. We also show that the Carnot efficiency regularly increases towards each transition between W and SB, with a large discontinuous decrease at the point of each transition. Finally, we propose well-defined empirical functions allowing for expressing the global non-equilibrium thermodynamical properties of the system in terms of either the mean surface temperature or the mean planetary emission temperature. While the specific results presented in this paper depend on some characteristics of the Earth system (e.g. rotation rate, position of the continents), this paves the way for the possibility of proposing efficient

  2. Climate mitigation potential of the San Pedro River riparian zone

    Treesearch

    Dean A. Martens; Jean E. T. McLain

    2005-01-01

    Carbon (C) and nitrogen (N) cycling within an open brush site, a sacaton (Sporobolus wrightii) grass and a mesquite (Prosopis velutina) grove, in the riparian zone was closely linked to the yearly litter N inputs. Yearly mesquite litter fall for 2 yr was remarkably similar and averaged 4.0 g N m-2 and 65 g C m...

  3. Defining and predicting urban-wildland interface zones using a GIS-based model

    Treesearch

    Lawrence R. Gering; Angel V. Chun; Steve Anderson

    2000-01-01

    Resource managers are beginning to experience a deluge of management conflicts as urban population centers expand into formerly wildland settings. Fire suppression, recreational, watershed management, and traditional forest management practices are activities that have become contentious in many locales. A better understanding of the interface zone between these two...

  4. How Much Curriculum Change Is Appropriate? Defining a Zone of Feasible Innovation

    ERIC Educational Resources Information Center

    Rogan, John M.

    2007-01-01

    The article grapples with the question of how much curriculum change is appropriate in a given context and in a given time frame. How can a balance be struck between stagnation, on the one hand, and the promotion of unrealistic innovation on the other? In answer to this dilemma, the concept of a zone of feasible innovation (ZFI) is proposed and…

  5. How Much Curriculum Change Is Appropriate? Defining a Zone of Feasible Innovation

    ERIC Educational Resources Information Center

    Rogan, John M.

    2007-01-01

    The article grapples with the question of how much curriculum change is appropriate in a given context and in a given time frame. How can a balance be struck between stagnation, on the one hand, and the promotion of unrealistic innovation on the other? In answer to this dilemma, the concept of a zone of feasible innovation (ZFI) is proposed and…

  6. Using MERRA, AMIP II, CMIP5 Outputs to Assess Actual and Potential Building Climate Zone Change and Variability From the Last 30 Years Through 2100

    NASA Astrophysics Data System (ADS)

    Stackhouse, P. W.; Westberg, D. J.; Hoell, J. M., Jr.; Chandler, W.; Zhang, T.

    2014-12-01

    In the US, residential and commercial building infrastructure combined consumes about 40% of total energy usage and emits about 39% of total CO2emission (DOE/EIA "Annual Energy Outlook 2013"). Thus, increasing the energy efficiency of buildings is paramount to reducing energy costs and emissions. Building codes, as used by local and state enforcement entities are typically tied to the dominant climate within an enforcement jurisdiction classified according to various climate zones. These climates zones are based upon a 30-year average of local surface observations and are developed by DOE and ASHRAE (formerly known as the American Society of Hearting, Refrigeration and Air-Conditioning Engineers). A significant shortcoming of the methodology used in constructing such maps is the use of surface observations (located mainly near airports) that are unequally distributed and frequently have periods of missing data that need to be filled by various approximation schemes. This paper demonstrates the usefulness of using NASA's Modern Era Retrospective-analysis for Research and Applications (MERRA) atmospheric data assimilation to derive the ASHRAE climate zone maps and then using MERRA to define the last 30 years of variability in climate zones. These results show that there is a statistically significant increase in the area covered by warmer climate zones and some tendency for a reduction of area in colder climate zones that require longer time series to confirm. Using the uncertainties of the basic surface temperature and precipitation parameters from MERRA as determined by comparison to surface measurements, we first compare patterns and variability of ASHRAE climate zones from MERRA relative to present day climate model runs from AMIP simulations to establish baseline sensitivity. Based upon these results, we assess the variability of the ASHRAE climate zones according to CMIP runs through 2100 using an ensemble analysis that classifies model output changes by

  7. Three-Dimensional Topographic Surface Changes in Response to Compartmental Volumization of the Medial Cheek: Defining a Malar Augmentation Zone.

    PubMed

    Stern, Carrie S; Schreiber, Jillian E; Surek, Chris C; Garfein, Evan S; Jelks, Elizabeth B; Jelks, Glenn W; Tepper, Oren M

    2016-05-01

    Given the widespread use of facial fillers and recent identification of distinct facial fat compartments, a better understanding of three-dimensional surface changes in response to volume augmentation is needed. Advances in three-dimensional imaging technology now afford an opportunity to elucidate these morphologic changes for the first time. A cadaver study was undertaken in which volumization of the deep medial cheek compartment was performed at intervals up to 4 cc (n = 4). Three-dimensional photographs were taken after each injection to analyze the topographic surface changes, which the authors define as the "augmentation zone." Perimeter, diameter, and projection were studied. The arcus marginalis of the inferior orbit consistently represented a fixed boundary of the augmentation zone, and additional cadavers underwent similar volumization following surgical release of this portion of the arcus marginalis (n = 4). Repeated three-dimensional computer analysis was performed comparing the augmentation zone with and without arcus marginalis release. Volumization of the deep medial cheek led to unique topographic changes of the malar region defined by distinct boundaries. Interestingly, the cephalic border of the augmentation zone was consistently noted to be at the level of the arcus marginalis in all specimens. When surgical release of the arcus marginalis was performed, the cephalic border of the augmentation zone was no longer restricted. Using advances in three-dimensional photography and computer analysis, the authors demonstrate characteristic surface anatomy changes in response to volume augmentation of facial compartments. This novel concept of the augmentation zone can be applied to volumization of other distinct facial regions. Therapeutic, V.

  8. Climate change and the future of seed zones

    Treesearch

    Francis Kilkenny; Brad St. Clair; Matt. Horning

    2013-01-01

    The use of native plants in wildland restoration is critical to the recovery and health of ecosystems. Information from genecological and reciprocal transplant common garden studies can be used to develop seed transfer guidelines and to predict how plants will respond to future climate change. Tools developed from these data, such as universal response functions and...

  9. Mesoscale Climate Simulations of Exoplanets in the Habitable Zone of M Dwarfs and Planet Habitability

    NASA Astrophysics Data System (ADS)

    Tian, F.

    2016-12-01

    As more and more potentially habitable exoplanets are discovered and the approaching opportunities to characterize them, the habitability of such planets is getting attention in the scientific community. Planetary atmosphere stability and planet climate are 2 key issues regarding planet habitability. In recent years there have been multiple works using 3-D general circulation models (GCM) to study the climate of exoplanets in the habitable zones of M dwarfs. However the spatial resolution of such models is usually rather low. Here we report new simulations on ocean exoplanets in the habitable zones of M dwarfs using a state-of-the-art mesoscale model, focusing on the differences between GCM and mesoscale model in terms of the inner boundary of the liquid water habitable zone. Because rocky exoplanets in the habitable zones of M dwarfs will likely be discovered within 3 years, we will also discuss the implications of mesoscale model on the characterization of such planets.

  10. Sensitivity of WRF model estimates to various PBL parameterizations in different climatic zones over India

    NASA Astrophysics Data System (ADS)

    Gunwani, Preeti; Mohan, Manju

    2017-09-01

    In the present work sensitivity of Weather Research Forecasting (WRF) Model has been carried out using five planetary boundary layer (PBL) schemes - Yonsei University Scheme (YSU), Mellor-Yamada-Janjić scheme (MYJ), Aymmetric Convective Model version 2 (ACM2), Quasi Normal Scale Elimination scheme (QNSE), Mellor-Yamada-Nakanishi-Niino scheme (MYNN) in different climatic zones over India namely Tropical, Temperate and Arid for surface meteorological parameters, upper air variables and planetary boundary layer height during summer and winter season. The model outputs have been compared with observations through standard statistical measures. The aim is to study the relative performance of these schemes, selecting the best option climatic zone-wise and thereby minimizing uncertainty in model predictions. WRF model performance evaluation shows better agreement for temperature and relative humidity compared to wind speed. Overall for India, ACM2, QNSE show good performance for temperature and relative humidity whereas ACM2, MYNN show better performance for wind speed though these may vary for different climatic zones. Geopotential height and wind over 850 hPa is well simulated by ACM2 and MYNN over India. For PBL height ACM2, MYNN and MYJ works best for Chennai, New Delhi and Kolkata respectively during summer period. However, for winter period MYJ works best for Chennai while, QNSE works best for New Delhi and Kolkata. Considering all meteorological parameters together, it is seen that for arid zone ACM2, QNSE and MYJ schemes work reasonably well. For temperate zone, ACM2, QNSE and MYNN schemes show better results. For tropical zone all PBL schemes work closely. Hence, depending on the application, parameter and climate zone, this study provides suitable recommendations for choosing PBL schemes appropriately for each zone and parameter separately for the Indian region.

  11. Agro-climatic zoning of Jatropha curcas as a subside for crop planning and implementation in Brazil.

    PubMed

    Yamada, Eliane S M; Sentelhas, Paulo C

    2014-11-01

    As jatropha (Jatropha curcas L.) is a recent crop in Brazil, the studies for defining its suitability for different regions are not yet available, even considering the promises about this plant as of high potential for marginal zones where poor soils and dry climate occur. Based on that, the present study had as objective to characterize the climatic conditions of jatropha's center of origin in Central America for establishing its climatic requirements and to develop the agro-climatic zoning for this crop for some Brazilian regions where, according to the literature, it would be suitable. For classifying the climatic conditions of the jatropha's center of origin, climate data from 123 weather stations located in Mexico (93) and in Guatemala (30) were used. These data were input for Thornthwaite and Mather's climatological water balance for determining the annual water deficiency (WD) and water surplus (WS) of each location, considering a soil water-holding capacity (SWHC) of 100 mm. Mean annual temperature (T m), WD, and WS data were organized in histograms for defining the limits of suitability for jatropha cultivation. The results showed that the suitable range of T m for jatropha cultivation is between 23 and 27 °C. T m between 15 and 22.9 °C and between 27.1 and 28 °C were classified as marginal by thermal deficiency and excess, respectively. T m below 15 °C and above 28 °C were considered as unsuitable for jatropha cultivation, respectively, by risk of frosts and physiological disturbs. For WD, suitability for rain-fed jatropha cultivation was considered when its value is below 360 mm, while between 361 and 720 mm is considered as marginal and over 720 mm unsuitable. The same order of suitability was also defined for WS, with the following limits: suitable for WS up to 1,200 mm; marginal for WS between 1,201 and 2,400 mm, and unsuitable for WS above 2,400 mm. For the crop zoning, the criteria previously defined were applied to 1,814 climate stations in

  12. Lymph node detection in IASLC-defined zones on PET/CT images

    NASA Astrophysics Data System (ADS)

    Song, Yihua; Udupa, Jayaram K.; Odhner, Dewey; Tong, Yubing; Torigian, Drew A.

    2016-03-01

    Lymph node detection is challenging due to the low contrast between lymph nodes as well as surrounding soft tissues and the variation in nodal size and shape. In this paper, we propose several novel ideas which are combined into a system to operate on positron emission tomography/ computed tomography (PET/CT) images to detect abnormal thoracic nodes. First, our previous Automatic Anatomy Recognition (AAR) approach is modified where lymph node zones predominantly following International Association for the Study of Lung Cancer (IASLC) specifications are modeled as objects arranged in a hierarchy along with key anatomic anchor objects. This fuzzy anatomy model built from diagnostic CT images is then deployed on PET/CT images for automatically recognizing the zones. A novel globular filter (g-filter) to detect blob-like objects over a specified range of sizes is designed to detect the most likely locations and sizes of diseased nodes. Abnormal nodes within each automatically localized zone are subsequently detected via combined use of different items of information at various scales: lymph node zone model poses found at recognition indicating the geographic layout at the global level of node clusters, g-filter response which hones in on and carefully selects node-like globular objects at the node level, and CT and PET gray value but within only the most plausible nodal regions for node presence at the voxel level. The models are built from 25 diagnostic CT scans and refined for an object hierarchy based on a separate set of 20 diagnostic CT scans. Node detection is tested on an additional set of 20 PET/CT scans. Our preliminary results indicate node detection sensitivity and specificity at around 90% and 85%, respectively.

  13. Hydrogen Sulfide Emissions from Sow Farm Lagoons across Climates Zones.

    PubMed

    Grant, Richard H; Boehm, Matthew T; Lawrence, Alfred J; Heber, Albert J

    2013-11-01

    Hydrogen sulfide (HS) emissions were measured periodically over the course of 2 yr at three sow waste lagoons representing humid mesothermal (North Carolina, NC), humid microthermal (Indiana, IN), and semiarid (Oklahoma, OK) climates. Emissions were determined using a backward Lagrangian stochastic model in conjunction with line-sampled HS concentrations and measured turbulence. The median annual sow-specific (area-specific) lagoon emissions at the OK farm were approximately 1.6 g head [hd] d (5880 µg m s), whereas those at the IN and NC sow farms were 0.035 g hd d (130 µg m s), and 0.041 g hd d (260 µg m s), respectively. Hydrogen sulfide emissions generally increased with wind speed. The daily HS emissions from the OK lagoon were greatest during the first half of the year and decreased as the year progressed. Emissions were episodic at the NC and IN lagoons. The generally low emissions at the NC and IN lagoons were probably a result of significant populations of purple sulfur bacteria maintained in the humid mesothermal and humid microthermal climates. Most of the large HS emission events at the NC and IN lagoons appeared to be a result of either precipitation events or liquid pump-out events. The high emissions at the OK lagoon in a semiarid climate were largely a result of high wind speeds enhancing both lagoon and air boundary layer mixing. The climate (air temperature, winds, and precipitation) appeared to influence the HS emissions from lagoons. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. Limited hydrologic response to Pleistocene climate change in deep vadose zones - Yucca Mountain, Nevada

    USGS Publications Warehouse

    Paces, J.B.; Neymark, L.A.; Whelan, J.F.; Wooden, J.L.; Lund, S.P.; Marshall, B.D.

    2010-01-01

    Understanding the movement of water through thick vadose zones, especially on time scales encompassing long-term climate change, is increasingly important as societies utilize semi-arid environments for both water resources and sites viewed as favorable for long-term disposal or storage of hazardous waste. Hydrologic responses to Pleistocene climate change within a deep vadose zone in the eastern Mojave Desert at Yucca Mountain, Nevada, were evaluated by uranium-series dating of finely layered hyalitic opal using secondary ion mass spectrometry. Opal is present within cm-thick secondary hydrogenic mineral crusts coating floors of lithophysal cavities in fractured volcanic rocks at depths of 200 to 300 m below land surface. Uranium concentrations in opal fluctuate systematically between 5 and 550 μg/g. Age-calibrated profiles of uranium concentration correlate with regional climate records over the last 300,000 years and produce time-series spectral peaks that have distinct periodicities of 100- and 41-ka, consistent with planetary orbital parameters. These results indicate that the chemical compositions of percolating solutions varied in response to near-surface, climate-driven processes. However, slow (micrometers per thousand years), relatively uniform growth rates of secondary opal and calcite deposition spanning several glacial–interglacial climate cycles imply that water fluxes in the deep vadose zone remained low and generally buffered from the large fluctuations in available surface moisture during different climates.

  15. Limited hydrologic response to Pleistocene climate change in deep vadose zones — Yucca Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Paces, James B.; Neymark, Leonid A.; Whelan, Joseph F.; Wooden, Joseph L.; Lund, Steven P.; Marshall, Brian D.

    2010-12-01

    Understanding the movement of water through thick vadose zones, especially on time scales encompassing long-term climate change, is increasingly important as societies utilize semi-arid environments for both water resources and sites viewed as favorable for long-term disposal or storage of hazardous waste. Hydrologic responses to Pleistocene climate change within a deep vadose zone in the eastern Mojave Desert at Yucca Mountain, Nevada, were evaluated by uranium-series dating of finely layered hyalitic opal using secondary ion mass spectrometry. Opal is present within cm-thick secondary hydrogenic mineral crusts coating floors of lithophysal cavities in fractured volcanic rocks at depths of 200 to 300 m below land surface. Uranium concentrations in opal fluctuate systematically between 5 and 550 μg/g. Age-calibrated profiles of uranium concentration correlate with regional climate records over the last 300,000 years and produce time-series spectral peaks that have distinct periodicities of 100- and 41-ka, consistent with planetary orbital parameters. These results indicate that the chemical compositions of percolating solutions varied in response to near-surface, climate-driven processes. However, slow (micrometers per thousand years), relatively uniform growth rates of secondary opal and calcite deposition spanning several glacial-interglacial climate cycles imply that water fluxes in the deep vadose zone remained low and generally buffered from the large fluctuations in available surface moisture during different climates.

  16. Species distribution models contribute to determine the effect of climate and interspecific interactions in moving hybrid zones.

    PubMed

    Engler, J O; Rödder, D; Elle, O; Hochkirch, A; Secondi, J

    2013-11-01

    Climate is a major factor delimiting species' distributions. However, biotic interactions may also be prominent in shaping geographical ranges, especially for parapatric species forming hybrid zones. Determining the relative effect of each factor and their interaction of the contact zone location has been difficult due to the lack of broad scale environmental data. Recent developments in species distribution modelling (SDM) now allow disentangling the relative contributions of climate and species' interactions in hybrid zones and their responses to future climate change. We investigated the moving hybrid zone between the breeding ranges of two parapatric passerines in Europe. We conducted SDMs representing the climatic conditions during the breeding season. Our results show a large mismatch between the realized and potential distributions of the two species, suggesting that interspecific interactions, not climate, account for the present location of the contact zone. The SDM scenarios show that the southerly distributed species, Hippolais polyglotta, might lose large parts of its southern distribution under climate change, but a similar gain of novel habitat along the hybrid zone seems unlikely, because interactions with the other species (H. icterina) constrain its range expansion. Thus, whenever biotic interactions limit range expansion, species may become 'trapped' if range loss due to climate change is faster than the movement of the contact zone. An increasing number of moving hybrid zones are being reported, but the proximate causes of movement often remain unclear. In a global context of climate change, we call for more interest in their interactions with climate change.

  17. [The role of ecovirological zoning in prediction of the influence of climatic changes on arbovirus habitats].

    PubMed

    Shchelkanov, M Iu; Gromashevskiĭ, V L; L'vov, D K

    2006-01-01

    The paper contains methodical basis of ecovirological zoning in the analysis of the problem of interrelation between climatic changes and the activity of natural nidi of arboviral infection. The authors offer an original hieroglyphic system of cartographic signs of arboviruses and a map of prevalence of arboviruses in various landscape zones of Noth Eurasia (within the boundaries of the former USSR.) They analyze the three main cartographic approaches to ecovirological zoning of natural territorial complexes, which imply analysis of a ralation to a landscape, conjugated component analysis, and paleographic reconstruction analysis.

  18. [Climatic risk zoning for banana and litchi's chilling injury in South China].

    PubMed

    Li, Na; Huo, Zhi-guo; He, Nan; Xiao, Jing-jing; Wen, Quan-pei

    2010-05-01

    Based on the 1951-2006 climatic observation data from 224 meteorological stations in South China (Guangdong Province, Guangxi Autonomous Region, and Fujian Province) and the historical information about the chilling injury losses of banana and litchi, the accumulated harmful chilling for the processes with minimum daily temperature < or = 5.0 degrees C and more than 3 days was used to indicate the climatic risk of chilling injury during the whole growth season, and an integrated climatic index with the background of climate change was constructed. The maps of geographical distribution of climatic risk probability for each grade chilling injury, and of integrated climatic risk zoning for banana and litchi's chilling injury were drawn, and the spatial variation of climatic risk for banana and litchi's chilling injury was commented. The results indicated that in the study area, climate warming might lead to the decrease of cold resistance of banana and litchi, which could increase the disaster risk of chilling injury. The geographical distribution of climatic risk probability for banana and litchi's chilling injury showed a zonal pattern. According to the integrated climatic risk index, the banana and litchi's chilling injury region was divided into three risk types, i.e., high risk, moderate risk, and low risk, which provided an important basis for the adjustment of agricultural production structure.

  19. Identification of novel cellular clusters define a specialized area in the cerebellar periventricular zone

    PubMed Central

    González-González, María Alejandra; Gómez-González, Gabriela B.; Becerra-González, Marymar; Martínez-Torres, Ataúlfo

    2017-01-01

    The periventricular zone of cerebellum is a germinative niche during the embryonic development, nevertheless its structural organization and functional implications in adult have not been widely studied. Here we disclose the presence of two novel clusters of cells in that area. The first one was named the subventricular cellular cluster (SVCC) and is composed of cells that express glial and neuronal markers. The second was named the ventromedial cord (VMC) and appears as a streak of biciliated cells with microvillosities facing the ventricle, that includes GFAP+ and nestin+ cells organized along the periventricular vasculature. The dorsal limit of the SVCC is associated with myelinated axons of neurons of unknown origin. This paper describes the characteristics and organization of these groups of cells. They can be observed from late embryonic development in the transgenic mouse line GFAP-GFP. The SVCC and VMC expand during early postnatal development but are restricted to the central area of the ventricle in adulthood. We did not find evidence of cell proliferation, cell migration or the presence of fenestrated blood vessels. These findings provide new insights into the knowledge of the cellular composition and structural organization of the periventricular zone of cerebellum. PMID:28106069

  20. Defining a "Zone of Impact": Transport Processes and Patterns for Small-Scale Land Runoff.

    NASA Astrophysics Data System (ADS)

    Largier, J. L.; Basdurak, B.

    2016-12-01

    Nearshore pollution is a well-recognized environmental problem, yet the pattern of this pollution is not well studied and it is little recognized in policy. Whether nutrients, pathogens or toxins, the highest concentrations of pollutants in the nearfield are controlled by transport and mixing, rather than decay of the constituent. Thus, this becomes a challenge to determine patterns of runoff (and tidal outflow) and to account for the dominant processes that control these patterns. Salinity and fecal indicator bacteria data exhibit coherent space-time patterns, indicating that a coherent "zone of impact" can be determined, i.e., a time-varying spatial zone in which the constituent of concern exceeds a reference concentration (level of concern). To explain field observations, modeling of small-scale runoff plumes and wave-driven transport can be used. In contrast to larger river plumes, wind forcing is a critical factor in plume behavior and the resultant pattern of pollution. This preliminary work suggests that coherent spatio-temporal patterns can explain the apparently not-so-well-behaved patterns of pollution that are reported when concentrations are under-sampled. And it throws out a challenge to nearshore oceanographers to better explain transport and mixing patterns for the benefit of reducing coastal pollution and its impacts.

  1. Defining the southwestern end of the Blytheville Arch, northeastern Arkansas: delimiting a seismic source zone in the New Madrid region

    USGS Publications Warehouse

    Crone, A.J.

    1998-01-01

    Vibroseis seismic-reflection profiles around the southwestern end of the Blytheville arch document the southwesternly extent of the arch and refine the length of a fault zone that coincides with the arch. The 74.3 km of newly interpreted profiles and previously described profiles form a network of lines across and around the southern end of the arch. The southwestern terminus of the arch is defined by the absence of significantly upwarped or extensively disrupted reflectors, which are diagnostic traits of the arch where it is well developed. The arch is 134 km long as documented here, which is only slightly longer than the length reported by previous studies. Differing opinions about the magnitude of the 1811-1812 New Madrid earthquakes could be partly explained by substantially longer seismic source zones, but this minor increase in source zone length does not reconcile the large differences in magnitude estimates of the events. If future earthquake ruptures associated with the arch are confined to areas of extensive deformation, then this well documented southwestern termination precludes a rupture substantially longer than ~134 km along the zone of seismicity that coincides with the axis of the Reelfoot rift.

  2. Climate change and temperate zone insects: the tyranny of thermodynamics meets the world of limited resources.

    PubMed

    Adamo, Shelley A; Baker, Jillian L; Lovett, Maggie M E; Wilson, Graham

    2012-12-01

    Climate change will result in warmer temperatures and an increase in the frequency and severity of extreme weather events. Given that higher temperatures increase the reproductive rate of temperate zone insects, insect population growth rates are predicted to increase in the temperate zone in response to climate. This consensus, however, rests on the assumption that food is freely available. However, under conditions of limited food, the reproductive output of the Texan cricket Gryllus texensis (Cade and Otte) was highest at its current normal average temperature and declined with increasing temperature. Moreover, low food availability decreased survival during a simulated heat wave. Therefore, the effects of climate change on this species, and possibly on many others, are likely to hinge on food availability. Extrapolation from our data suggests that G. texensis will show larger yearly fluctuations in population size as climate change continues, and this will also have ecological repercussions. Only those temperate zone insects with a ready supply of food (e.g., agricultural pests) are likely to experience the predicted increase in population growth in response to climate change; food-limited species are likely to experience a population decline.

  3. Defining an Abrasion Index for Lunar Surface Systems as a Function of Dust Interaction Modes and Variable Concentration Zones

    NASA Technical Reports Server (NTRS)

    Kobrick, Ryan L.; Klaus, David M.; Street, Kenneth W., Jr.

    2010-01-01

    Unexpected issues were encountered during the Apollo era of lunar exploration due to detrimental abrasion of materials upon exposure to the fine-grained, irregular shaped dust on the surface of the Moon. For critical design features involving contact with the lunar surface and for astronaut safety concerns, operational concepts and dust tolerance must be considered in the early phases of mission planning. To systematically define material selection criteria, dust interaction can be characterized by two-body or three-body abrasion testing, and subcategorically by physical interactions of compression, rolling, sliding and bending representing specific applications within the system. Two-body abrasion occurs when a single particle or asperity slides across a given surface removing or displacing material. Three-body abrasion occurs when multiple particles interact with a solid surface, or in between two surfaces, allowing the abrasives to freely rotate and interact with the material(s), leading to removal or displacement of mass. Different modes of interaction are described in this paper along with corresponding types of tests that can be utilized to evaluate each configuration. In addition to differential modes of abrasion, variable concentrations of dust in different zones can also be considered for a given system design and operational protocol. These zones include: (1) outside the habitat where extensive dust exposure occurs, (2) in a transitional zone such as an airlock or suitport, and (3) inside the habitat or spacesuit with a low particle count. These zones can be used to help define dust interaction frequencies, and corresponding risks to the systems and/or crew can be addressed by appropriate mitigation strategies. An abrasion index is introduced that includes the level of risk, R, the hardness of the mineralogy, H, the severity of the abrasion mode, S, and the frequency of particle interactions, F.

  4. Climate variability and vadose zone controls on damping of transient recharge

    USGS Publications Warehouse

    Corona, Claudia R.; Gurdak, Jason J.; Dickinson, Jesse; Ferré, T.P.A.; Maurer, Edwin P.

    2017-01-01

    Increasing demand on groundwater resources motivates understanding of the controls on recharge dynamics so model predictions under current and future climate may improve. Here we address questions about the nonlinear behavior of flux variability in the vadose zone that may explain previously reported teleconnections between global-scale climate variability and fluctuations in groundwater levels. We use hundreds of HYDRUS-1D simulations in a sensitivity analysis approach to evaluate the damping depth of transient recharge over a range of periodic boundary conditions and vadose zone geometries and hydraulic parameters that are representative of aquifer systems of the conterminous United States (U.S). Although the models were parameterized based on U.S. aquifers, findings from this study are applicable elsewhere that have mean recharge rates between 3.65 and 730 mm yr–1. We find that mean infiltration flux, period of time varying infiltration, and hydraulic conductivity are statistically significant predictors of damping depth. The resulting framework explains why some periodic infiltration fluxes associated with climate variability dampen with depth in the vadose zone, resulting in steady-state recharge, while other periodic surface fluxes do not dampen with depth, resulting in transient recharge. We find that transient recharge in response to the climate variability patterns could be detected at the depths of water levels in most U.S. aquifers. Our findings indicate that the damping behavior of transient infiltration fluxes is linear across soil layers for a range of texture combinations. The implications are that relatively simple, homogeneous models of the vadose zone may provide reasonable estimates of the damping depth of climate-varying transient recharge in some complex, layered vadose zone profiles.

  5. Quantifying Hydro-biogeochemical Model Sensitivity in Assessment of Climate Change Effect on Hyporheic Zone Processes

    NASA Astrophysics Data System (ADS)

    Song, X.; Chen, X.; Dai, H.; Hammond, G. E.; Song, H. S.; Stegen, J.

    2016-12-01

    The hyporheic zone is an active region for biogeochemical processes such as carbon and nitrogen cycling, where the groundwater and surface water mix and interact with each other with distinct biogeochemical and thermal properties. The biogeochemical dynamics within the hyporheic zone are driven by both river water and groundwater hydraulic dynamics, which are directly affected by climate change scenarios. Besides that, the hydraulic and thermal properties of local sediments and microbial and chemical processes also play important roles in biogeochemical dynamics. Thus for a comprehensive understanding of the biogeochemical processes in the hyporheic zone, a coupled thermo-hydro-biogeochemical model is needed. As multiple uncertainty sources are involved in the integrated model, it is important to identify its key modules/parameters through sensitivity analysis. In this study, we develop a 2D cross-section model in the hyporheic zone at the DOE Hanford site adjacent to Columbia River and use this model to quantify module and parametric sensitivity on assessment of climate change. To achieve this purpose, We 1) develop a facies-based groundwater flow and heat transfer model that incorporates facies geometry and heterogeneity characterized from a field data set, 2) derive multiple reaction networks/pathways from batch experiments with in-situ samples and integrate temperate dependent reactive transport modules to the flow model, 3) assign multiple climate change scenarios to the coupled model by analyzing historical river stage data, 4) apply a variance-based global sensitivity analysis to quantify scenario/module/parameter uncertainty in hierarchy level. The objectives of the research include: 1) identifing the key control factors of the coupled thermo-hydro-biogeochemical model in the assessment of climate change, and 2) quantify the carbon consumption in different climate change scenarios in the hyporheic zone.

  6. Complexity of the deep San Andreas Fault zone defined by cascading tremor

    NASA Astrophysics Data System (ADS)

    Shelly, David R.

    2015-02-01

    Weak seismic vibrations--tectonic tremor--can be used to delineate some plate boundary faults. Tremor on the deep San Andreas Fault, located at the boundary between the Pacific and North American plates, is thought to be a passive indicator of slow fault slip. San Andreas Fault tremor migrates at up to 30 m s-1, but the processes regulating tremor migration are unclear. Here I use a 12-year catalogue of more than 850,000 low-frequency earthquakes to systematically analyse the high-speed migration of tremor along the San Andreas Fault. I find that tremor migrates most effectively through regions of greatest tremor production and does not propagate through regions with gaps in tremor production. I interpret the rapid tremor migration as a self-regulating cascade of seismic ruptures along the fault, which implies that tremor may be an active, rather than passive participant in the slip propagation. I also identify an isolated group of tremor sources that are offset eastwards beneath the San Andreas Fault, possibly indicative of the interface between the Monterey Microplate, a hypothesized remnant of the subducted Farallon Plate, and the North American Plate. These observations illustrate a possible link between the central San Andreas Fault and tremor-producing subduction zones.

  7. Climate change and the northern Russian treeline zone.

    PubMed

    MacDonald, G M; Kremenetski, K V; Beilman, D W

    2008-07-12

    The Russian treeline is a dynamic ecotone typified by steep gradients in summer temperature and regionally variable gradients in albedo and heat flux. The location of the treeline is largely controlled by summer temperatures and growing season length. Temperatures have responded strongly to twentieth-century global warming and will display a magnified response to future warming. Dendroecological studies indicate enhanced conifer recruitment during the twentieth century. However, conifers have not yet recolonized many areas where trees were present during the Medieval Warm period (ca AD 800-1,300) or the Holocene Thermal Maximum (HTM; ca 10,000-3,000 years ago). Reconstruction of tree distributions during the HTM suggests that the future position of the treeline due to global warming may approximate its former Holocene maximum position. An increased dominance of evergreen tree species in the northern Siberian forests may be an important difference between past and future conditions. Based on the slow rates of treeline expansion observed during the twentieth century, the presence of steep climatic gradients associated with the current Arctic coastline and the prevalence of organic soils, it is possible that rates of treeline expansion will be regionally variable and transient forest communities with species abundances different from today's may develop.

  8. Temporo-spatial analyses define epileptogenic and functional zones in a case of Dyke-Davidoff-Masson syndrome.

    PubMed

    Hsin, Y L; Chuang, M F; Shen, T W; Harnod, T

    2011-11-01

    Dyke-Davidoff-Masson syndrome (DDMS) is a rare epilepsy syndrome that is characterized by cerebral hemiatrophy, homolateral skull hyperplasia, hyperpneumatization of the paranasal sinuses, seizures with or without mental retardation, and contralateral hemiparesis. We describe a case of DDMS in a 40-year-old female who had complex partial seizures with occasional secondary generalization since the age of 4 years. Her seizure frequency was 10-20 seizures/month even though she took four antiepileptic drugs. We applied magnetic resonance imaging (MRI), positron emission tomography (PET), functional MRI, and invasive electroencephalography (EEG) to define her epileptogenic and functional zones. Brain MRI showed prominent atrophy in the left frontal dorsal and lateral regions and mild atrophy of the left superior temporal gyrus and left parietal gyri. Interictal PET revealed decreased glucose metabolism in the atrophic regions. Functional MRI demonstrated that the inferior frontal and inferior parieto-occipital regions of the right hemisphere were activated by language testing. Invasive EEG revealed that the left lateral temporal lobe was the sole source of her seizures. Our results imply that the "metabolic border zone" rather than the atrophic region plays an important role in seizure activity, and that reorganization of functional zones occur after cerebral damage early in life. Copyright © 2011 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  9. Importance of unsaturated zone flow for simulating recharge in a humid climate

    USGS Publications Warehouse

    Hunt, R.J.; Prudic, D.E.; Walker, J.F.; Anderson, M.P.

    2008-01-01

    Transient recharge to the water table is often not well understood or quantified. Two approaches for simulating transient recharge in a ground water flow model were investigated using the Trout Lake watershed in north-central Wisconsin: (1) a traditional approach of adding recharge directly to the water table and (2) routing the same volume of water through an unsaturated zone column to the water table. Areas with thin (less than 1 m) unsaturated zones showed little difference in timing of recharge between the two approaches; when water was routed through the unsaturated zone, however, less recharge was delivered to the water table and more discharge occurred to the surface because recharge direction and magnitude changed when the water table rose to the land surface. Areas with a thick (15 to 26 m) unsaturated zone were characterized by multimonth lags between infiltration and recharge, and, in some cases, wetting fronts from precipitation events during the fall overtook and mixed with infiltration from the previous spring snowmelt. Thus, in thicker unsaturated zones, the volume of water infiltrated was properly simulated using the traditional approach, but the timing was different from simulations that included unsaturated zone flow. Routing of rejected recharge and ground water discharge at land surface to surface water features also provided a better simulation of the observed flow regime in a stream at the basin outlet. These results demonstrate that consideration of flow through the unsaturated zone may be important when simulating transient ground water flow in humid climates with shallow water tables.

  10. Variability in apparent soil organic carbon turnover times across climate zones and vegetation classes

    NASA Astrophysics Data System (ADS)

    Khomik, M.; Reichstein, M.; Schrumpf, M.; Beer, C.; Curiel Yuste, J.; Janssens, I.; Luyssaert, S.; Subke, J.; Trumbore, S.; Wutzler, T.; Fluxnet Lathuile: Www. Fluxdata. Org

    2011-12-01

    Our understanding about the climatic controls on the rate of soil organic carbon (SOC) decomposition is still limited and greatly debated, especially the temperature sensitivity of SOC decomposition. Some argue that SOC turnover time (TO) decreases exponentially with increasing temperatures, while others disagree. Based on a number of assumptions, we calculated the ratio between soil CO2 efflux and soil bulk carbon stocks, from which we obtained an estimate of apparent TO for bulk soils across a selection of forested sites around the globe. We used data collected from site-PIs and from recently-available databases of: soil chamber flux measurements (Global soil respiration database: code.google.com/p/srdb/), ecosystem carbon flux measurements (FLUXNET LaThuile dataset: www.fluxdata.org), and global soil carbon stock estimates (Harmonized world soil database: www.iiasa.ac.at/Research/LUC/External-World-soil-database/HTML/). We investigated across-site variability of these apparent TO values in relation to climate (i.e. site's mean annual temperature, MAT, and total annual precipitation, TAP) and vegetation classes (i.e. broadleaf deciduous, needle-leaf deciduous, broadleaf evergreen, and needle-leaf evergreen). We found that, when all data points were considered, TO decreased exponentially with increasing MAT and TAP, in accordance with past studies, although the relationship with TAP was not as strong as with MAT. The overall negative exponential relationship was maintained even when the data was analyzed under the combined effects of MAT and TAP and vegetation class. TO at sites with low annual precipitation and low mean annual temperatures were high (i.e. the rate of decomposition was low). However, we also found that this overall global exponential relationship was largely driven by the difference in TO between sites located in the boreal climate zone and sites located in the other climate zones considered (i.e. tropical, Mediterranean and temperate climate

  11. Defining a safe player run-off zone around rugby union playing areas.

    PubMed

    Fuller, Colin W; Jones, Rhys; Fuller, Andrew D

    2015-10-01

    To identify the circumstances in which international rugby players exit the playing area during match activities and to define a safe run-off distance around the playing area. An observational study using video recordings of 102 matches associated with the Rugby World Cup (2011), Rugby Championship (2013, 2014) and Six Nations Championship (2013, 2014) were used to analyse every event in which one or more players exited the playing area during normal match activities. The circumstances in which a player exited the playing area were categorised using a range of parameters: playing position, location, out-of-play region, match activity, distance travelled over the touchline, contacts made with pitchside fixtures and fittings. Ninety-five per cent of player-excursions took place within 5.2 m of the touchline. Players exiting the playing area were nearly three times more likely to be a back than a forward (p<0.001) and the event was more likely to take place when a team was defending than attacking (p<0.001). Being forced out of play during a contact event (70%) was the major reason for players exiting the playing area. Most players (88%) exiting the playing area only made contact with the perimeter area surface; a small proportion of players contacted touchline flags (6.1%), advertising boards (2.3%) and TV cameras/equipment (1.0%). A minimum hazard-free distance of 5 m around a Rugby pitch is proposed based on the 95% percentile frequency distribution of player-excursion events into the areas contiguous with the playing area. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas, Observations and Modelling

    DTIC Science & Technology

    2013-09-30

    drag coefficient on the directional spreading of ocean waves. J. Geophys. Res., 117, doi:10.1029/2012JC007920, 7p Toffoli, A., L. Loffredo, P . Le Roy...REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4 . TITLE AND SUBTITLE Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas...developed for obtaining trends based on short ( 4 -year) segments of the altimeter records. This technique will be used to investigate wave climate

  13. Database of Low-e Storm Window Energy Performance across U.S. Climate Zones

    SciTech Connect

    Culp, Thomas D.; Cort, Katherine A.

    2014-09-04

    This is an update of a report that describes process, assumptions, and modeling results produced Create a Database of U.S. Climate-Based Analysis for Low-E Storm Windows. The scope of the overall effort is to develop a database of energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by cliamte zone.

  14. Climate-induced change of environmentally defined floristic domains: A conservation based vulnerability framework

    Treesearch

    Debbie Jewitt; Barend F.N. Erasmus; Peter S. Goodman; Timothy G. O' Connor; William W. Hargrove; Damian M. Maddalena; Ed. T.F. Witkowski

    2015-01-01

    Global climate change is having marked influences on species distributions, phenology and ecosystem composition and raises questions as to the effectiveness of current conservation strategies. Conservation planning has only recently begun to adequately account for dynamic threats such as climate change. We propose a method to incorporate climate-dynamic environmental...

  15. Booming during a bust: Asynchronous population responses of arid zone lizards to climatic variables

    NASA Astrophysics Data System (ADS)

    Read, John L.; Kovac, Kelli-Jo; Brook, Barry W.; Fordham, Damien A.

    2012-04-01

    The productivity of arid environments and the reproductive success of vertebrates in these systems, are typically thought to be primarily influenced by rainfall patterns. Data from our 15 year study at an Australian arid zone site reveals asynchronous demographic responses to rainfall and other climatic variables among different lizard species. We show that, in addition to precipitation, key demographic rates (fecundity, recruitment and survival) are correlated strongly with temporal variability in temperature, during and prior to the breeding season, and also to the density of sympatric lizard species. There were nine-fold fluctuations through time in the relative abundance of two similar-sized Ctenotus species, and asynchronous recruitment success and survival among other species, despite the absence of direct anthropogenic affects Understanding the drivers and magnitude of the substantial natural variability in arid-zone lizard assemblages is integral to predicting and interpreting their responses to future land use or climate-change scenarios.

  16. Climate controls how ecosystems size the root zone storage capacity at catchment scale

    NASA Astrophysics Data System (ADS)

    Gao, H.; Hrachowitz, M.; Schymanski, S. J.; Fenicia, F.; Sriwongsitanon, N.; Savenije, H. H. G.

    2014-11-01

    The root zone moisture storage capacity (SR) of terrestrial ecosystems is a buffer providing vegetation continuous access to water and a critical factor controlling land-atmospheric moisture exchange, hydrological response, and biogeochemical processes. However, it is impossible to observe directly at catchment scale. Here, using data from 300 diverse catchments, it was tested that, treating the root zone as a reservoir, the mass curve technique (MCT), an engineering method for reservoir design, can be used to estimate catchment-scale SR from effective rainfall and plant transpiration. Supporting the initial hypothesis, it was found that MCT-derived SR coincided with model-derived estimates. These estimates of parameter SR can be used to constrain hydrological, climate, and land surface models. Further, the study provides evidence that ecosystems dynamically design their root systems to bridge droughts with return periods of 10-40 years, controlled by climate and linked to aridity index, inter-storm duration, seasonality, and runoff ratio.

  17. Differential thermal adaptation of clonal strains of a protist morphospecies originating from different climatic zones.

    PubMed

    Boenigk, Jens; Jost, Steffen; Stoeck, Thorsten; Garstecki, Tobias

    2007-03-01

    Eco-physiological variation and local adaptation are key issues in microbial ecology. Here, we investigated the thermal adaptation of 19 strains of the same Spumella morphospecies (Chrysophyceae, Heterokonta). In order to test for local adaptation and the existence of specific ecotypes we analysed growth rates of these strains, which originated from different climate regions. We applied temperature-adaptation as an eco-physiological marker and analysed growth rates of the different Spumella strains at temperatures between 0 degrees C and 35 degrees C. The temperatures allowing for maximal growth of strains from temperate and warm climatic zones ranged between 19.9 degrees C and 33.4 degrees C. Phylogenetically, most of these 'warm'-adapted strains fall into two different previously defined 18S rDNA Spumella clusters, one of them consisting of mostly soil organisms and the other one being a freshwater cluster. As a rule, the 'warm'-adapted strains of the soil cluster grew slower than the 'warm'-adapted isolates within the freshwater cluster. This difference most probably reflect different strategies, i.e. the formation of cysts at the expense of lower growth rates in soil organisms. In contrast, as expected, all isolates from Antarctica were cold-adapted and grew already around melting point of freshwater. Surprisingly, optimum temperature for these strains was between 11.8 degrees C and 17.7 degrees C and maximum temperature tolerated was between 14.6 degrees C and 23.5 degrees C. Our data indicate that despite the relatively high optimal temperature of most Antarctic strains, they may have a relative advantage below 5-10 degrees C only. Based on the thermal adaptation of the flagellate strains the Antarctic strains were clearly separated from the other investigated strains. This may indicate a limited dispersal of flagellates to and from Antarctica. Even if the latter assumption needs support from more data, we argue that the high levels of eco-physiological and

  18. An index-based method to assess risks of climate-related hazards in coastal zones: The case of Tetouan

    NASA Astrophysics Data System (ADS)

    Satta, Alessio; Snoussi, Maria; Puddu, Manuela; Flayou, Latifa; Hout, Radouane

    2016-06-01

    The regional risk assessment carried out within the ClimVar & ICZM Project identified the coastal zone of Tetouan as a hotspot of the Mediterranean Moroccan coast and so it was chosen for the application of the Multi-Scale Coastal Risk Index for Local Scale (CRI-LS). The local scale approach provides a useful tool for local coastal planning and management by exploring the effects and the extensions of the hazards and combining hazard, vulnerability and exposure variables in order to identify areas where the risk is relatively high. The coast of Tetouan is one of the coastal areas that have been most rapidly and densely urbanized in Morocco and it is characterized by an erosive shoreline. Local authorities are facing the complex task of balancing development and managing coastal risks, especially coastal erosion and flooding, and then be prepared to the unavoidable impacts of climate change. The first phase of the application of the CRI-LS methodology to Tetouan consisted of defining the coastal hazard zone, which results from the overlaying of the erosion hazard zone and the flooding hazard zone. Nineteen variables were chosen to describe the Hazards, Vulnerability and Exposure factors. The scores corresponding to each variable were calculated and the weights assigned through an expert judgement elicitation. The resulting values are hosted in a geographic information system (GIS) platform that enables the individual variables and aggregated risk scores to be color-coded and mapped across the coastal hazard zone. The results indicated that 10% and 27% of investigated littoral fall under respectively very high and high vulnerability because of combination of high erosion rates with high capital land use. The risk map showed that some areas, especially the flood plains of Restinga, Smir and Martil-Alila, with distances over 5 km from the coast, are characterized by high levels of risk due to the low topography of the flood plains and to the high values of exposure

  19. [Thermal compensation of respiration in pulmonate snails (Pulmonata) of Arion and Deroceras genera living in polar and temperate climatic zone].

    PubMed

    Zotin, A A; Ozerniuk, N D

    2002-01-01

    Comparison of respiration rate in pulmonate snails living in various climatic zones demonstrated higher constant a in representatives of Arion genus (A. subfucus and A. fasciatus) from Polar Area (Murmansk Region) as compared to inhabitants of temperate latitudes (Moscow Region). The snails of Deroceras genus (D. reticulatum) from these two climatic zones were indistinguishable by relative standard metabolism. Different effects of climatic thermal conditions on respiration rates in representatives of these two snail genera can be due to their specific biology. Representatives of Deroceras genus are short-cycle synanthropic species, while the snails of Arion genus are long-cycle species living mostly in the forest zone.

  20. Climate change impact on groundwater levels in the Guarani Aquifer outcrop zone

    NASA Astrophysics Data System (ADS)

    Melo, D. D.; Wendland, E.

    2013-12-01

    The unsustainable use of groundwater in many countries might cause water availability restrictions in the future. Such issue is likely to worsen due to predicted climate changes for the incoming decades. As numerous studies suggest, aquifers recharge rates will be affected as a result of climate change. The Guarani Aquifer System (GAS) is one of the most important transboundary aquifer in the world, providing drinkable water for millions of people in four South American countries (Brazil, Argentina, Uruguay and Paraguay). Considering the GAS relevance and how its recharge rates might be altered by climatic conditions anomalies, the objective of this work is to assess possible climate changes impacts on groundwater levels in this aquifer outcrop zone. Global Climate Models' (GCM) outputs were used as inputs in a transient flux groundwater model created using the software SPA (Simulation of Process in Aquifers), enabling groundwater table fluctuation to be evaluated under distinct climatic scenarios. Six monitoring wells, located in a representative basin (Ribeirão da Onça basin) inside a GAS outcrop zone (ROB), provided water table measurements between 2004 and 2011 to calibrate the groundwater model. Using observed climatic data, a water budget method was applied to estimate recharge in different types of land uses. Statistically downscaled future climate scenarios were used as inputs for that same recharge model, which provided data for running SPA under those scenarios. The results show that most of the GCMs used here predict temperature arises over 275,15 K and major monthly rainfall mean changes to take place in the dry season. During wet seasons, those means might experience around 50% decrease. The transient model results indicate that water table variations, derived from around 70% of the climate scenarios, would vary below those measured between 2004 and 2011. Among the thirteen GCMs considered in this work, only four of them predicted more extreme

  1. Temporal Variation of NDVI and the Drivers of Climate Variables in the Arctic Tundra Transition Zone

    NASA Astrophysics Data System (ADS)

    Lee, J.; Ryu, Y.; Lee, Y. K.

    2016-12-01

    The Arctic is a sensitive region to temperature, which is drastically increasing with climate change. Vegetation in transition zones of the sub-arctic tundra biome are most sensitive to the warming climate, as temperature in the Arctic ecosystem is one of important limiting factors of vegetation growth and decomposition. Previous research in the transition zone show that there is a difference of sensible heat flux (21 Wm-2), Leaf Area Index increase from 0.58 - 2.76 and canopy height from 0.1 - 6.1m across dwarf and tall shrubs to forest, however, we lack understanding of NDVI trend of this zone. To better understand the vegetation in transition zones of the arctic ecosystem, we analyze the long-term trend of NDVI (AVHRR 3g GIMMs data), temperature and precipitation (Climate Research Unit data) trend from 1982 - 2010 in Council, Alaska that is a region where arctic tundra is transitioning to boreal forest. We also analyze how the climatic factors, temperature or precipitation, affect NDVI. Annual precipitation had the highest interannual variability compared to temperature and NDVI. There was an overall decreasing trend of annual maximum NDVI (y = -0.0019x+4.7). During 1982 to 2003, NDVI and temperature had a similar pattern, but when temperature suddenly jumped to 13.2°C in 2004, NDVI and precipitation declined. This study highlights that temperature increase does not always lead to greening, but after a certain threshold they may cause damage to sub-arctic tundra vegetation.

  2. Climate, soil, and vegetation controls on the temporal variability of vadose zone transport

    NASA Astrophysics Data System (ADS)

    Harman, C. J.; Rao, P. S. C.; Basu, N. B.; McGrath, G. S.; Kumar, P.; Sivapalan, M.

    2011-10-01

    Temporal patterns of solute transport and transformation through the vadose zone are driven by the stochastic variability of water fluxes. This is determined by the hydrologic filtering of precipitation variability into infiltration, storage, drainage, and evapotranspiration. In this work we develop a framework for examining the role of the hydrologic filtering and, in particular, the effect of evapotranspiration in determining the travel time and delivery of sorbing, reacting solutes transported through the vadose zone by stochastic rainfall events. We describe a 1-D vertical model in which solute pulses are tracked as point loads transported to depth by a series of discrete infiltration events. Numerical solutions of this model compare well to the Richards equation-based HYDRUS model for some typical cases. We then utilize existing theory of the stochastic dynamics of soil water to derive analytical and semianalytical expressions for the probability density functions (pdf's) of solute travel time and delivery. The moments of these pdf's directly relate the mean and variance of expected travel times to the water balance and show how evapotranspiration tends to reduce (and make more uncertain) the mass of a degrading solute delivered to the base of the vadose zone. The framework suggests a classification of different modes hydrologic filtering depending on hydroclimatic and landscape controls. Results suggest that variability in travel times decreases with soil depth in wet climates but increases with soil depth in dry climates. In dry climates, rare large storms can be an important mechanism for leaching to groundwater.

  3. A 'regionalized' approach based on climate zones for improved Interpolation of global precipitation δ18O

    NASA Astrophysics Data System (ADS)

    Terzer, S.; Araguas, L.; Aggarwal, P. K.

    2012-12-01

    Spatial interpolation of point-based precipitation isotope measurements is a common task required to generate 'isoscapes' which are used for various applications in hydrology, climatology, ecology and forensics. While various prediction methods have been explored (employing interpolation and/or multiple regression), one of their basic objectives is to identify a globally suitable parameterization. On the other hand, regional models have been developed to improve interpolation on a limited spatial extent. We have developed a new approach based on climate zones to 'regionalize' regression parameters, building a global prediction model based on a set of regionally adjusted multiple regression/interpolation procedures. A climate zone boundary fuzzification technique was used to smooth out climate zone transitions. Evaluation of the new model in comparison with a globally fitted one shows that the regionalized model has a lower model uncertainty at similar confidence intervals. The resulting global interpolation thus provides an improved and reliable map of precipitation isotopes with significant differences in predicted values in most parts of the world.

  4. [Changes of climate and fire dynamic in China vegetation zone during 1961-2010].

    PubMed

    Tian, Xiao-Rui; Zhao, Feng-Jun; Shu, Li-Fu; Miao, Qing-Lin; Wang, Ming-Yu

    2014-11-01

    Climate, vegetation and human activities have influences on regional fire regimes. To understand the fire regimes for ecological zones on national scale is the base for carrying on the forest fire management. Daily observed temperature and precipitation data in 1961-2010 were interpolated into grids for China mainland with spatial resolution of 0.250 x 0.250, which was used to analyze their changes in fire season for eight ecological zones. Mann-Kendall test method was used for trend analysis of climate and fire dynamics. The results indicated that the average temperature for the areas with forests showed a significant linear upward trend in 1961-2010, but the precipitation didn't have the tendency. The average temperature in fire season for all the ecological zones increased significantly in the study period, and the most increment occurred in temperate semi-arid/arid steppe regions. There was no significant change in precipitation in fire season for most regions. Forest fire numbers for the mainland showed obvious fluctuations, but the affected forest areas decreased significantly. The curves of fire numbers and affected forest areas showed a bimodal shape for all ecological zones, except those showed a significant increase in the coniferous forest region in the temperate arid areas.

  5. What's the meaning of local? Using molecular markers to define seed transfer zones for ecological restoration in Norway.

    PubMed

    Jørgensen, Marte Holten; Elameen, Abdelhameed; Hofman, Nadine; Klemsdal, Sonja; Malaval, Sandra; Fjellheim, Siri

    2016-06-01

    According to the Norwegian Diversity Act, practitioners of restoration in Norway are instructed to use seed mixtures of local provenance. However, there are no guidelines for how local seed should be selected. In this study, we use genetic variation in a set of alpine species (Agrostis mertensii, Avenella flexuosa, Carex bigelowii, Festuca ovina, Poa alpina and Scorzoneroides autumnalis) to define seed transfer zones to reduce confusion about the definition of 'local seeds'. The species selected for the study are common in all parts of Norway and suitable for commercial seed production. The sampling covered the entire alpine region (7-20 populations per species, 3-15 individuals per population). We characterised genetic diversity using amplified fragment length polymorphisms. We identified different spatial genetic diversity structures in the species, most likely related to differences in reproductive strategies, phylogeographic factors and geographic distribution. Based on results from all species, we suggest four general seed transfer zones for alpine Norway. This is likely more conservative than needed for all species, given that no species show more than two genetic groups. Even so, the approach is practical as four seed mixtures will serve the need for restoration of vegetation in alpine regions in Norway.

  6. Groundwater-surface water interactions in the hyporheic zone under climate change scenarios.

    PubMed

    Zhou, Shangbo; Yuan, Xingzhong; Peng, Shuchan; Yue, Junsheng; Wang, Xiaofeng; Liu, Hong; Williams, D Dudley

    2014-12-01

    Slight changes in climate, such as the rise of temperature or alterations of precipitation and evaporation, will dramatically influence nearly all freshwater and climate-related hydrological behavior on a global scale. The hyporheic zone (HZ), where groundwater (GW) and surface waters (SW) interact, is characterized by permeable sediments, low flow velocities, and gradients of physical, chemical, and biological characteristics along the exchange flows. Hyporheic metabolism, that is biogeochemical reactions within the HZ as well as various processes that exchange substances and energy with adjoining systems, is correlated with hyporheic organisms, habitats, and the organic matter (OM) supplied from GW and SW, which will inevitably be influenced by climate-related variations. The characteristics of the HZ in acting as a transition zone and in filtering and purifying exchanged water will be lost, resulting in a weakening of the self-purification capacity of natural water bodies. Thus, as human disturbances intensify in the future, GW and SW pollution will become a greater challenge for mankind than ever before. Biogeochemical processes in the HZ may favor the release of carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) under climate change scenarios. Future water resource management should consider the integrity of aquatic systems as a whole, including the HZ, rather than independently focusing on SW and GW.

  7. Energy Savings of Low-E Storm Windows and Panels across US Climate Zones

    SciTech Connect

    Culp, Thomas D.; Cort, Katherine A.

    2015-10-01

    This report builds off of previous modeling work related to low-e storm windows used to create a "Database of U.S. Climate-Based Analysis for Low-E Storm Windows." This work updates similar studies using new fuel costs and examining the separate contributions of reduced air leakage and reduced coefficients of overall heat transfer and solar heat gain. In this report we examine the energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates, excluding the impact from infiltration reductions, which tend to vary using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by climate zone.

  8. A guideline for sizing Photovoltaic panels across different climatic zones in Burkina Faso

    NASA Astrophysics Data System (ADS)

    Waongo, M.; Koalaga, Z.; Zougmore, F.

    2012-02-01

    In many developing countries a long time series of solar radiation measurements are not often available. This is due to the cost, maintenance and calibration requirements of measuring devices. Consequently, the use of solar energy by Photovoltaic (PV) conversion copes with the choice and the optimization of the PV system. This work concerned the analysis of climate parameters strongly influencing the Photovoltaic (PV) systems energy production and the simulation of an ideal system based on a single PV module. Estimation and analysis of time series of climate parameters covered a set of six weather stations with respect to the three climatic zones in Burkina Faso (BF), over 38 years. The analysis showed that the solar irradiation in BF lies between 3 kWh/m2/day and 7.5 kWh/m2/day. The highest values of the solar irradiation are measured in the Northern part of the country while lowest values are measured in the Southern part. Daily mean temperature for all weather stations was greater than the Standard Test Condition (STC) temperature (25°C) over a long period of the year. Information on solar irradiation and temperature is fundamental for PV systems sizing process. For PV performance evaluation, a simulation is carried out using an ideal system composed of a single PV module from TENESOL Company. This simulation is performed for three classes of climatic conditions "Mean situation", "Adverse situation", and "Beneficial situation", and evaluated for six sitesacross BF. The results revealed intra-annual and spatial variability of Maximum Power (MP). Across BF, MP varied between 60 W/day and 190 W/day in Sahelian zone, between 65 W/day and 185 W/day in soudano-sahelian zone, and between 67 W/day and 208 W/day in Soudanian zone. MP intra-annual variability is higher during the period July-August, mainly for "Beneficial situation". The negative effect of temperature on PV energy production is specially amplified in Sahelian zone due to its highest temperatures. This

  9. Effects of Atlantic warm pool variability over climate of South America tropical transition zone

    NASA Astrophysics Data System (ADS)

    Ricaurte Villota, Constanza; Romero-Rodríguez, Deisy; Andrés Ordoñez-Zuñiga, Silvio; Murcia-Riaño, Magnolia; Coca-Domínguez, Oswaldo

    2016-04-01

    Colombia is located in the northwestern corner of South America in a climatically complex region due to the influence processes modulators of climate both the Pacific and Atlantic region, becoming in a transition zone between phenomena of northern and southern hemisphere. Variations in the climatic conditions of this region, especially rainfall, have been attributed to the influence of the El Nino Southern Oscillation (ENSO), but little is known about the interaction within Atlantic Ocean and specifically Caribbean Sea with the environmental conditions of this region. In this work We studied the influence of the Atlantic Warm Pool (AWP) on the Colombian Caribbean (CC) climate using data of Sea Surface Temperature (SST) between 1900 - 2014 from ERSST V4, compared with in situ data SIMAC (National System for Coral Reef Monitoring in Colombia - INVEMAR), rainfall between 1953-2013 of meteorological stations located at main airports in the Colombian Caribbean zone, administered by IDEAM, and winds data between 2003 - 2014 from WindSat sensor. The parameters analyzed showed spatial differences throughout the study area. SST anomalies, representing the variability of the AWP, showed to be associated with Multidecadal Atlantic Oscillation (AMO) and with the index of sea surface temperature of the North-tropical Atlantic (NTA), the variations was on 3 to 5 years on the ENSO scale and of approximately 11 years possibly related to solar cycles. Rainfall anomalies in the central and northern CC respond to changes in SST, while in the south zone these are not fully engage and show a high relationship with the ENSO. Finally, the winds also respond to changes in SST and showed a signal approximately 90 days possibly related to the Madden-Julian Oscillation, whose intensity depends on the CC region being analyzed. The results confirm that region is a transition zone in which operate several forcing, the variability of climate conditions is difficult to attribute only one, as ENSO

  10. Human-water interactions in Myanmar's Dry Zone under climate change

    NASA Astrophysics Data System (ADS)

    Taft, Linda; Evers, Mariele

    2016-04-01

    Understanding human-water interactions is particularly essential in countries where the economy and the people's well-being and income strongly depend on the availability and quality of sufficient water resources. Such a strong dependency on water is existent in Myanmar's Dry Zone located in the central Ayeyarwady River basin. In this area, rainfall is associated with high heterogeneity across space and time. Precipitation amounts in the Dry Zone (500-1000 mm annually) are generally less compared to other regions in Myanmar (up to 4000-6000 mm). Following the Global Climate Risk Index, Myanmar is one of the countries which were most affected by extreme weather events between 1994 and 2013. Severe drought periods e.g in the years 1997-1998, 2010 and 2014 led to crop failures and water shortage in the Dry Zone, where more than 14 mio people predominantly practice agriculture. Due to the high variability of rainfalls, farming is only possible with irrigation, mainly conducted by canal systems from the rivers and groundwater withdrawal. Myanmar is recently facing big challenges which result from comprehensive political and economic reforms since 2011. These may also include increasing water use by new industrial zones and urbanization. However, not only policy and economy modify the need for water. Variability of river runoff and changes in seasonality are expected as a result of climate change. The overarching goal of the study is to understand and increase the knowledge on human-water-climate interactions and to elaborate possible future scenarios for Myanmar's Dry Zone. It is not well studied yet how current and future climate change and increasing human impact will influence the country's abundant water resources including groundwater. Therefore, the first step of this study is to identify the major drivers within the central Ayeyarwady River basin. We are in the process of collecting and analyzing data sets and information including hydrologic and eco

  11. Analysis of climatic conditions and preliminary assessment of alternative cooling strategies for houses in California transition climate zones

    SciTech Connect

    Huang, Y.J.; Zhang, H.

    1995-07-01

    This is a preliminary scoping study done as part of the {open_quotes}Alternatives to Compressive Cooling in California Transition Climates{close_quotes} project, which has the goal of demonstrating that houses in the transitional areas between the coast and the Central Valley of California do not require air-conditioning if they are properly designed and operated. The first part of this report analyzes the climate conditions within the transitional areas, with emphasis on design rather than seasonal conditions. Transitional climates are found to be milder but more variable than those further inland. The design temperatures under the most stringent design criteria, e.g. 0.1 % annual, are similar to those in the Valley, but significantly lower under more relaxed design criteria, e.g., 2% annual frequency. Transition climates also have large day-night temperature swings, indicating significant potential for night cooling, and wet-bulb depressions in excess of 25 F, indicating good potential for evaporative cooling. The second part of the report is a preliminary assessment using DOE-2 computer simulations of the effectiveness of alternative cooling and control strategies in improving indoor comfort conditions in two conventional Title-24 houses modeled in various transition climate locations. The cooling measures studied include increased insulation, light colors, low-emissivity glazing, window overhangs, and exposed floor slab. The control strategies studied include natural and mechanical ventilation, and direct and two-stage evaporative cooling. The results indicate the cooling strategies all have limited effectiveness, and need to be combined to produce significant improvements in indoor comfort. Natural and forced ventilation provide similar improvements in indoor conditions, but during peak cooling periods, these will still be above the comfort zone. Two-stage evaporative coolers can maintain indoor comfort at all hours, but not so direct evaporative coolers.

  12. Changes of the transitional climate zone in East Asia: past and future

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Chen, Wen; Huang, Gang; Zeng, Gang

    2017-08-01

    The transitional climate zone (TCZ) between humid and arid regions in East Asia is characterized by sharp climate and biome gradients, interaction between the East Asian summer monsoon and the mid-latitude westerly winds and mixed agriculture-pasture activities. Consequently, it is highly vulnerable to natural disturbances and particularly human-driven global change. This study aims to illuminate the spatial and temporal variation of TCZ across both the retrospective and the prospective periods. In the historical period, both the front and rear edges of TCZ exhibit wide year-to-year excursions and have experienced coastward migration with increasing aridity throughout TCZ. Furthermore, precipitation fluctuation mainly contributes to interannual variability of TCZ whereas potential evaporation behavior dominates the long-term trends of TCZ. Models are capable of largely reproducing the shape and orientation of TCZ, although northwestward bias is apparent. In global warming scenario period, there will be continuing southeastward displacement for the front edge but the opposite northwestward movement is projected for the rear one, as a consequence of significant drying trends in the humid zone together with regime shifts towards humid conditions in the arid zone. Despite expanded TCZ sector, however, the available water resources inside it suffer little magnitude changes without preferential tendency towards either drier or wetter conditions, implying neither deleterious nor beneficial effects on the TCZ environment. Moreover, interannual variability of TCZ is expected to become stronger, resulting in more frequent occurrences of extreme swings. Finally, it is noted that uncertainty arising from climate models dominates in the TCZ than dispersed emission scenarios, in contrast to the situation in humid and arid zones.

  13. Changes of the transitional climate zone in East Asia: past and future

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Chen, Wen; Huang, Gang; Zeng, Gang

    2016-10-01

    The transitional climate zone (TCZ) between humid and arid regions in East Asia is characterized by sharp climate and biome gradients, interaction between the East Asian summer monsoon and the mid-latitude westerly winds and mixed agriculture-pasture activities. Consequently, it is highly vulnerable to natural disturbances and particularly human-driven global change. This study aims to illuminate the spatial and temporal variation of TCZ across both the retrospective and the prospective periods. In the historical period, both the front and rear edges of TCZ exhibit wide year-to-year excursions and have experienced coastward migration with increasing aridity throughout TCZ. Furthermore, precipitation fluctuation mainly contributes to interannual variability of TCZ whereas potential evaporation behavior dominates the long-term trends of TCZ. Models are capable of largely reproducing the shape and orientation of TCZ, although northwestward bias is apparent. In global warming scenario period, there will be continuing southeastward displacement for the front edge but the opposite northwestward movement is projected for the rear one, as a consequence of significant drying trends in the humid zone together with regime shifts towards humid conditions in the arid zone. Despite expanded TCZ sector, however, the available water resources inside it suffer little magnitude changes without preferential tendency towards either drier or wetter conditions, implying neither deleterious nor beneficial effects on the TCZ environment. Moreover, interannual variability of TCZ is expected to become stronger, resulting in more frequent occurrences of extreme swings. Finally, it is noted that uncertainty arising from climate models dominates in the TCZ than dispersed emission scenarios, in contrast to the situation in humid and arid zones.

  14. Variations in the kinematics of deformation along the Zagros inclined transpression zone, Iran: Implications for defining a curved inclined transpression zone

    NASA Astrophysics Data System (ADS)

    Sarkarinejad, Khalil; Partabian, Abdolreza; Faghih, Ali

    2013-03-01

    The combination of inclined collision and plate boundary shape can control the nature of deformation and the sense of shear along a transpression zone. The present study investigated the effects of a boundary zone with curvilinear shape along a transpression zone on the kinematics of deformation. The kinematics of the Zagros transpression zone varies with the orientation of the zone boundary. Detailed structural and microstructural studies showed sinistral sense of shear on the southeastern part of the Zagros inclined transpression zone (Fars Arc), but dextral sense of shear on the northwestern part of the zone. It is inferred that the both senses of shear were developed coevally under a bulk general shear, regional-scale deformation along a curved inclined transpression miming the shape of the Fras Arc of the Zagros and the reentrant of the Bandar Abbas Syntaxis. The Zagros transpression zone formed by inclined continental collision between the Afro-Arabian continent and Iranian microcontinent.

  15. Suitability Analysis and Projected Climate Change Impact on Banana and Coffee Production Zones in Nepal.

    PubMed

    Ranjitkar, Sailesh; Sujakhu, Nani M; Merz, Juerg; Kindt, Roeland; Xu, Jianchu; Matin, Mir A; Ali, Mostafa; Zomer, Robert J

    The Government of Nepal has identified opportunities in agricultural commercialization, responding to a growing internal demand and expansion of export markets to reduce the immense trade deficit. Several cash crops, including coffee and bananas, have been identified in the recently approved Agriculture Development Strategy. Both of these crops have encouraged smallholder farmers to convert their subsistence farming practices to more commercial cultivation. Identification of suitable agro-ecological zones and understanding climate-related issues are important for improved production and livelihoods of smallholder farmers. Here, the suitability of coffee and banana crops is analyzed for different agro-ecological zones represented by Global Environmental Stratification (GEnS). Future shifts in these suitability zones are also predicted. Plantation sites in Nepal were geo-referenced and used as input in species distribution modelling. The multi-model ensemble model suggests that climate change will reduce the suitable growing area for coffee by about 72% across the selected emission scenarios from now to 2050. Impacts are low for banana growing, with a reduction in suitability by about 16% by 2050. Bananas show a lot of potential for playing an important role in Nepal as a sustainable crop in the context of climate change, as this study indicates that the amount of area suited to banana growing will grow by 40% by 2050. Based on our analysis we recommend possible new locations for coffee plantations and one method for mitigating climate change-related problems on existing plantations. These findings are expected to support planning and policy dialogue for mitigation and support better informed and scientifically based decision-making relating to these two crops.

  16. Suitability Analysis and Projected Climate Change Impact on Banana and Coffee Production Zones in Nepal

    PubMed Central

    Sujakhu, Nani M.; Merz, Juerg; Kindt, Roeland; Xu, Jianchu; Matin, Mir A.; Ali, Mostafa; Zomer, Robert J.

    2016-01-01

    The Government of Nepal has identified opportunities in agricultural commercialization, responding to a growing internal demand and expansion of export markets to reduce the immense trade deficit. Several cash crops, including coffee and bananas, have been identified in the recently approved Agriculture Development Strategy. Both of these crops have encouraged smallholder farmers to convert their subsistence farming practices to more commercial cultivation. Identification of suitable agro-ecological zones and understanding climate-related issues are important for improved production and livelihoods of smallholder farmers. Here, the suitability of coffee and banana crops is analyzed for different agro-ecological zones represented by Global Environmental Stratification (GEnS). Future shifts in these suitability zones are also predicted. Plantation sites in Nepal were geo-referenced and used as input in species distribution modelling. The multi-model ensemble model suggests that climate change will reduce the suitable growing area for coffee by about 72% across the selected emission scenarios from now to 2050. Impacts are low for banana growing, with a reduction in suitability by about 16% by 2050. Bananas show a lot of potential for playing an important role in Nepal as a sustainable crop in the context of climate change, as this study indicates that the amount of area suited to banana growing will grow by 40% by 2050. Based on our analysis we recommend possible new locations for coffee plantations and one method for mitigating climate change-related problems on existing plantations. These findings are expected to support planning and policy dialogue for mitigation and support better informed and scientifically based decision-making relating to these two crops. PMID:27689354

  17. Regional Climate Zone Modeling of a Commercial Absorption Heat Pump Hot Water Heater Part 1: Southern and South Central Climate Zones

    SciTech Connect

    Geoghegan, Patrick J; Shen, Bo; Keinath, Christopher M.; Garrabrant, Michael A.

    2016-01-01

    Commercial hot water heating accounts for approximately 0.78 Quads of primary energy use with 0.44 Quads of this amount from natural gas fired heaters. An ammonia-water based commercial absorption system, if fully deployed, could achieve a high level of savings, much higher than would be possible by conversion to the high efficiency nonheat-pump gas fired alternatives. In comparison with air source electric heat pumps, the absorption system is able to maintain higher coefficients of performance in colder climates. The ammonia-water system also has the advantage of zero Ozone Depletion Potential and low Global Warming Potential. A thermodynamic model of a single effect ammonia-water absorption system for commercial space and water heating was developed, and its performance was investigated for a range of ambient and return water temperatures. This allowed for the development of a performance map which was then used in a building energy modeling software. Modeling of two commercial water heating systems was performed; one using an absorption heat pump and another using a condensing gas storage system. The energy and financial savings were investigated for a range of locations and climate zones in the southern and south central United States. A follow up paper will analyze northern and north/central regions. Results showed that the system using an absorption heat pump offers significant savings.

  18. The world is not flat: defining relevant thermal landscapes in the context of climate change.

    PubMed

    Sears, Michael W; Raskin, Evan; Angilletta, Michael J

    2011-11-01

    Although climates are rapidly changing on a global scale, these changes cannot easily be extrapolated to the local scales experienced by organisms. In fact, such generalizations might be quite problematic. For instance, models used to predict shifts in the ranges of species during climate change rarely incorporate data resolved to <1 km(2), although most organisms integrate climatic drivers at much smaller scales. Empirical studies alone suggest that the operative temperatures of many organisms vary by as much as 10-20 °C on a local scale, depending on vegetation, geology, and topography. Furthermore, this variation in abiotic factors ignores thermoregulatory behaviors that many animals use to balance heat loads. Through a set of simulations, we demonstrate how variability in elevational topography can attenuate the effects of warming climates. These simulations suggest that changing climates do not always impact organisms negatively. Importantly, these simulations involve well-known relationships in biophysical ecology that show how no two organisms experience the same climate in the same way. We suggest that, when coupled with thermoregulatory behavior, variation in topographic features can mask the acute effect of climate change in many cases. © The Author 2011. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

  19. Hazards and climatic impact of subduction-zone volcanism: A Global And Historical Perspective

    NASA Astrophysics Data System (ADS)

    Tilling, Robert I.

    Subduction-zone volcanoes account for more than 80 percent of the documented eruptions in recorded history, even though volcanism—deep and, hence, unobserved—along the global oceanic ridge systems overwhelmingly dominates in eruptive output. Because subduction-zone eruptions can be highly explosive, they pose some of the greatest natural hazards to society if the eruptions occur in densely populated regions. Of the six worst volcanic disasters since A.D. 1600, five have occurred at subduction-zone volcanoes: Unzen, Japan (1792); Tambora, Indonesia (1815); Krakatau, Indonesia (1883); Mont Pelée, Martinique (1902); and Nevado del Ruiz, Colombia (1985). Sulfuric acid droplets in stratospheric volcanic clouds produced by voluminous explosive eruptions can influence global climate. The 1815 Tambora eruption caused in 1816 a decrease of several Celsius degrees in average summer temperature in Europe and the eastern United States and Canada, resulting in the well-known "Year Without Summer." Similarly, the eruptions of El Chichon (Mexico) in 1982 and of Mount Pinatubo (Philippines) in 1991 lowered average temperatures for the northern hemisphere by as much as 0.2 to 0.5 °C, respectively. However, eruption-induced climatic effects of historical eruptions appear to be short-lived, lasting at most for only a few years.

  20. Toward daily climate scenarios for Canadian Arctic coastal zones with more realistic temperature-precipitation interdependence

    NASA Astrophysics Data System (ADS)

    Gennaretti, Fabio; Sangelantoni, Lorenzo; Grenier, Patrick

    2015-12-01

    The interdependence between climatic variables should be taken into account when developing climate scenarios. For example, temperature-precipitation interdependence in the Arctic is strong and impacts on other physical characteristics, such as the extent and duration of snow cover. However, this interdependence is often misrepresented in climate simulations. Here we use two two-dimensional (2-D) methods for statistically adjusting climate model simulations to develop plausible local daily temperature (Tmean) and precipitation (Pr) scenarios. The first 2-D method is based on empirical quantile mapping (2Dqm) and the second on parametric copula models (2Dcopula). Both methods are improved here by forcing the preservation of the modeled long-term warming trend and by using moving windows to obtain an adjustment specific to each day of the year. These methods were applied to a representative ensemble of 13 global climate model simulations at 26 Canadian Arctic coastal sites and tested using an innovative cross-validation approach. Intervariable dependence was evaluated using correlation coefficients and empirical copula density plots. Results show that these 2-D methods, especially 2Dqm, adjust individual distributions of climatic time series as adequately as one common one-dimensional method (1Dqm) does. Furthermore, although 2Dqm outperforms the other methods in reproducing the observed temperature-precipitation interdependence over the calibration period, both 2Dqm and 2Dcopula perform similarly over the validation periods. For cases where temperature-precipitation interdependence is important (e.g., characterizing extreme events and the extent and duration of snow cover), both 2-D methods are good options for producing plausible local climate scenarios in Canadian Arctic coastal zones.

  1. Climatic and Hydrological Changes of Past 100 Years in Asian Arid Zone

    NASA Astrophysics Data System (ADS)

    Feng, Zhaodong; Salnikov, Vitaliy; Xu, Changchun

    2014-05-01

    The Asian Arid Zone (AAZ) is here defined to include the following regions: northwestern China, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. Generally speaking, the AAZ has experienced a temperature rising during the past 100 years that was significantly faster than the global average (0.14 ºC per decade). Specifically, the rate was 0.39 ºC per decade in northwestern China (1950-2010), 0.26 ºC per decade in Kazakhstan (1936-2005), 0.22 ºC per decade in Mongolia (1940-2010), 0.29 ºC per decade in Uzbekistan (1950-2005), 0.18 ºC per decade in Turkmenistan (1961-1995). It should be noted that the mountainous parts of AAZ seems to have experienced a slower rate of temperature rising. For example, the rate was 0.10 ºC per decade in Tajikistan (1940-2005) and was 0.08 ºC per decade in Kyrgyzstan (1890-2005). Precipitation has a slight increasing trend in northwestern China, but it has fluctuated along a near-constant line in the rest of the AAZ. Hydrological data from high-elevation basin show that the runoff has been increasing primarily as a result of rising temperature that caused increases in ice melting. A natural decreasing trend of surface runoff in low-elevation basins is undeniable and the decreasing trend is attributable to intensified evaporation under warming conditions. It is true that the total amount of runoff in the Tianshan Mountains and the associated basins has been increased primarily as a result of temperature rising-resulted increases in ice melting. But, approaching to the turning point of glacier-melting supplies to runoff will pose a great threat to socio-economic sustainability and to ecological security. The turning point refers to the transition from increasing runoff to decreasing runoff within ice melting supplied watersheds under a warming climate.

  2. Genetic differentiation of strongyloides stercoralis from two different climate zones revealed by 18S ribosomal DNA sequence comparison.

    PubMed

    Pakdee, Wallop; Thaenkham, Urusa; Dekumyoy, Paron; Sa-Nguankiat, Surapol; Maipanich, Wanna; Pubampen, Somchit

    2012-11-01

    Over 70 countries in tropical and subtropical zones are endemic areas for Strongyloides stercoralis, with a higher prevalence of the parasite often occurring in tropical regions compared to subtropical ones. In order to explore genetic variations of S. stercoralis form different climate zones, 18S ribosomal DNA of parasite specimens obtained from Thailand were sequenced and compared with those from Japan. The maximum likelihood indicates that S. stercoralis populations from these two different climate zones have genetically diverged. The genetic relationship between S. stercoralis populations is not related to the host species, but rather to moisture and temperature. These factors may directly drive genetic differentiation among isolated populations of S. stercoralis.

  3. Sensitivity of agro-environmental zones in Spain to global climatic change

    NASA Astrophysics Data System (ADS)

    Vanwalleghem, T.; Guzmán, G.; Vanderlinden, K.; Laguna, A.; Giraldez, J. V.

    2014-12-01

    Soil has a key role in the regulation of carbon, water and nutrient cycles. Traditionally, agricultural soil management was oriented towards optimizing productivity. Nowadays, mitigation of climate change effects and maintaining long-term soil quality are evenly important. Developing policy guidelines for best management practices need to be site-specific, given the large spatial variability of environmental conditions within the EU. Therefore, it is necessary to classify the different farming zones that are susceptible to soil degradation. Especially in Mediterranean areas, this variability and its susceptibility to degradation is higher than in other areas of the EU. The objective of this study is therefore to delineate current agro-environmental zones in Spain and to determine the effect of global climate change on this classification in the future. The final objective is to assist policy makers in scenario analysis with respect to soil conservation. Our classification scheme is based on soil, topography and climate (seasonal temperature and rainfall) variables. We calculated slope and elevation based on a SRTM-derived DEM, soil texture was extracted from the European Soil Database and seasonal mean, minimum and maximum precipitation and temperature data were gridded from publically available weather station data (Aemet). Global change scenarios are average downscaled ensemble predictions for the emission scenarios A2 and B2. The k-means method was used for classification of the 10 km x 10 km gridded variables. Using the before-mentioned input variables, the optimal number of agro-environmental zones we obtained is 8. The classification corresponds well with the observed distribution of farming typologies in Spain. The advantage of this method is that it is a simple, objective method which uses only readily available, public data. As such, its extrapolation to other countries of the EU is straightforward. Finally, it presents a tool for policy makers to assess

  4. Epidemiology of ixodid ticks in cattle population of various agro-climatic zones of Punjab, India.

    PubMed

    Singh, Nirbhay Kumar; Rath, Shitanshu Shekhar

    2013-12-01

    To determine the epidemiology of ixodid ticks in bovines of different agro-climatic zones of Punjab state, India. A total of 4 459 cattle of all age groups and sex were examined from eighteen districts of five major agro-climatic zones of Punjab state, India. The overall prevalence of ixodid ticks, Rhipicephalus microplus (R. microplus), Hyalomma anatolicum anatolicum (H. a. anatolicum) and mixed infestation were 58.06%, 50.16%, 11.34% and 3.45%, respectively. Among the various agro-climatic zones highest prevalence rate of R. microplus and H. a. anatolicum were recorded in submountain undulating region (79.36%) and western region (20.40%), respectively indicating that R. microplus prefers a hot and humid environment whereas, arid and semi arid conditions suit better for H. a. anatolicum. The overall prevalence of ixodid ticks was highest in monsoon season (83.74%), followed by summer (69.01%) and least in winters (31.64%) and a significant variation (P<0.01) was also observed; whereas, maximum prevalence of R. microplus and H. a. anatolicum were recorded in monsoon (72.42%) and summers (18.06%), respectively. Among the various age groups maximum tick infestation was recorded in calves <6 months of age (72.59%), followed by 6 months -1 year age group (61.74%) and least in >1year age group (55.02%) and the difference was statistically significant (P<0.01). Also a significantly higher (P<0.01) infestation rates of ixodid ticks was observed in males. The findings of the current study would provide a basis for evolving effective control strategy for the management of ticks in bovines of the region. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  5. Resonant slow fault slip in subduction zones forced by climatic load stress.

    PubMed

    Lowry, Anthony R

    2006-08-17

    Global Positioning System (GPS) measurements at subduction plate boundaries often record fault movements similar to earthquakes but much slower, occurring over timescales of approximately 1 week to approximately 1 year. These 'slow slip events' have been observed in Japan, Cascadia, Mexico, Alaska and New Zealand. The phenomenon is poorly understood, but several observations hint at the processes underlying slow slip. Although slip itself is silent, seismic instruments often record coincident low-amplitude tremor in a narrow (1-5 cycles per second) frequency range. Also, modelling of GPS data and estimates of tremor location indicate that slip focuses near the transition from unstable ('stick-slip') to stable friction at the deep limit of the earthquake-producing seismogenic zone. Perhaps most intriguingly, slow slip is periodic at several locations, with recurrence varying from 6 to 18 months depending on which subduction zone (or even segment) is examined. Here I show that such periodic slow fault slip may be a resonant response to climate-driven stress perturbations. Fault slip resonance helps to explain why slip events are periodic, why periods differ from place to place, and why slip focuses near the base of the seismogenic zone. Resonant slip should initiate within the rupture zone of future great earthquakes, suggesting that slow slip may illuminate fault properties that control earthquake slip.

  6. Climate change and groundwater ecohydrology: Simulating subsurface flow and discharge zones in Covey Hill, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Levison, J.; Larocque, M.; Ouellet, M.; van Waterschoot, L.

    2013-12-01

    Nearly 2 billion people use groundwater and in Canada it is the potable water supply for about 30% of the population. Groundwater is also used in industrial and agricultural applications, and contributes to important hydrological habitats for various species. Limited research has been conducted to determine the potential impacts of climate change on groundwater. Local studies are crucial to better understand how, for example, increased duration and frequency of storms or drought periods may affect groundwater dependent ecosystems in order to anticipate and mitigate the impacts. Thus, the aim of this research is to explore the effects of climate change on a groundwater-surface water interacting system that supports a fragile ecosystem. This research is used to inform ecological conservation measures. The research site is the 17500 ha Covey Hill Natural Laboratory, which is located on the Quebec, Canada and New York State, USA border in the Chateauguay River watershed. At various locations within the Natural Laboratory there is continuous monitoring of groundwater levels and river flows. Covey Hill is an important recharge zone for the regional aquifer and provides habitat for endangered salamanders in discharge zones. Two hydrogeological models were constructed to represent flow at the site. First, a three-dimensional, finite difference model was developed using MODFLOW software to simulate overall groundwater flow at the research site. Second, a smaller-scale, discrete fracture, transient, three-dimensional, finite difference, integrated model was developed using HydroGeoSphere software to represent in better detail flow from bedrock springs that occur at mid-slope and provide the habitat for endangered salamanders. The models were used to: 1) observe groundwater flow under current climate conditions; 2) quantify water dynamics in response to climate change using 10 scenarios from the Canadian Regional Climate Model (for 1971-2000 and 2041-2070 time periods); and 3

  7. Hydrological Responses to Climate Change and to LUCC in Asian Arid Zone

    NASA Astrophysics Data System (ADS)

    Feng, Zhaodong

    2013-04-01

    The arid Asian zone is one of the most sensitive areas to the global climate change. For instance, the temperature has been rising at a rate of 0.39K/10yrs in the arid northwestern China during the past an half of century, being 2.78 times of the global average. In the arid Asian zone, water resource is a key factor restricting the socio-economic development and threatening the ecological security. Under the global warming conditions, water resource systems of the arid Asian zone are most likely becoming increasingly vulnerable, especially under the projected increasing population and expanding economy in arid Asian zone. Hydrological data from glacier-supplied rivers in the Tian Shan Mountains for example show that the runoff has been increasing primarily as a result of rising temperature that caused increases in ice melting. But, the decreasing trend of surface runoff in low-elevation basins is undeniable and the decreasing trend is attributable to the increasingly intensified human activities. Specifically, increasingly intensified water consumption for irrigation and the associated massive constructions of water conservancy projects were responsible for the decreasing trend of runoff. And, the decreasing trend has been severely jeopardizing the ecological security in the lower reaches of the arid river basins. In arid northwestern China, about 85% of the water resources are formed in high elevations and the glacier-melting contribution to runoff has been doubled since 1980's. Approaching to the turning point of glacier-melting supplies to runoff will pose a great threat to socio-economic sustainability and to ecological security. The turning point refers to the transition from increasing runoff to decreasing runoff within glacier-melting supplied watersheds under warming climate.

  8. The role of climate in the dynamics of a hybrid zone in Appalachian salamanders

    USGS Publications Warehouse

    Walls, Susan

    2009-01-01

    I examined the potential influence of climate change on the dynamics of a previously studied hybrid zone between a pair of terrestrial salamanders at the Coweeta Hydrologic Laboratory, U.S. Forest Service, in the Nantahala Mountains of North Carolina, USA. A 16-year study led by Nelson G. Hairston, Sr. revealed that Plethodon teyahalee and Plethodon shermani hybridized at intermediate elevations, forming a cline between 'pure' parental P. teyahalee at lower elevations and 'pure' parental P. shermani at higher elevations. From 1974 to 1990 the proportion of salamanders at the higher elevation scored as 'pure' P. shermani declined significantly, indicating that the hybrid zone was spreading upward. To date there have been no rigorous tests of hypotheses for the movement of this hybrid zone. Using temperature and precipitation data from Coweeta, I re-analyzed Hairston's data to examine whether the observed elevational shift was correlated with variation in either air temperature or precipitation from the same time period. For temperature, my analysis tracked the results of the original study: the proportion of 'pure' P. shermani at the higher elevation declined significantly with increasing mean annual temperature, whereas the proportion of 'pure' P. teyahalee at lower elevations did not. There was no discernable relationship between proportions of 'pure' individuals of either species with variation in precipitation. From 1974 to 1990, low-elevation air temperatures at the Coweeta Laboratory ranged from annual means of 11.8 to 14.2 °C, compared with a 55-year average (1936-1990) of 12.6 °C. My re-analyses indicate that the upward spread of the hybrid zone is correlated with increasing air temperatures, but not precipitation, and provide an empirical test of a hypothesis for one factor that may have influenced this movement. My results aid in understanding the potential impact that climate change may have on the ecology and evolution of terrestrial salamanders in

  9. The role of climate in the dynamics of a hybrid zone in Appalachian salamanders

    USGS Publications Warehouse

    Walls, S.C.

    2009-01-01

    I examined the potential influence of climate change on the dynamics of a previously studied hybrid zone between a pair of terrestrial salamanders at the Coweeta Hydrologic Laboratory, U.S. Forest Service, in the Nantahala Mountains of North Carolina, USA. A 16-year study led by Nelson G. Hairston, Sr. revealed that Plethodon teyahalee and Plethodon shermani hybridized at intermediate elevations, forming a cline between 'pure' parental P. teyahalee at lower elevations and 'pure' parental P. shermani at higher elevations. From 1974 to 1990 the proportion of salamanders at the higher elevation scored as 'pure' P. shermani declined significantly, indicating that the hybrid zone was spreading upward. To date there have been no rigorous tests of hypotheses for the movement of this hybrid zone. Using temperature and precipitation data from Coweeta, I re-analyzed Hairston's data to examine whether the observed elevational shift was correlated with variation in either air temperature or precipitation from the same time period. For temperature, my analysis tracked the results of the original study: the proportion of 'pure' P. shermani at the higher elevation declined significantly with increasing mean annual temperature, whereas the proportion of 'pure' P. teyahalee at lower elevations did not. There was no discernable relationship between proportions of 'pure' individuals of either species with variation in precipitation. From 1974 to 1990, low-elevation air temperatures at the Coweeta Laboratory ranged from annual means of 11.8 to 14.2??C, compared with a 55-year average (1936-1990) of 12.6??C. My re-analyses indicate that the upward spread of the hybrid zone is correlated with increasing air temperatures, but not precipitation, and provide an empirical test of a hypothesis for one factor that may have influenced this movement. My results aid in understanding the potential impact that climate change may have on the ecology and evolution of terrestrial salamanders in

  10. [Microbial biom different soils and soil and climatic zones Poltava region].

    PubMed

    2014-01-01

    Researches of microbiological diversity of soil on natural grassland and farmland in conditions of soil- climatic zones of Poltava oblast were conducted. General microbiological activities of soil (intensity of linen decomposition, %), numerosity of the main ecological-trophic groups of soil microorganisms, numerosity of fungi were detected. Coefficients of mineralization-mobilization, pedotroficity, oligotrophicity were calculated in accordance with correlation of the main ecological-trophic groups of soil microorganisms. Results of soil microbiological monitoring are analyzed and generalized. Was determined that soil of natural ecosystem (natural grassland and virgin land) has highest intensity of decomposition of organic matter and was the most provided of nutrient in comparison with farmland.

  11. [Microbial biom of different soils and soil-climatic zones of Poltava region].

    PubMed

    Patyka, V P; Taranenko, S V; Taranenko, A O; Kalinichenko, A V

    2014-01-01

    Researches of microbiological diversity of soil on natural grassland and farmland in conditions of soil- climatic zones of Poltava oblast were conducted. General microbiological activities of soil (intensity of linen decomposition, %), numerosity of the main ecological-trophic groups of soil microorganisms, numerosity of fungi were detected. Coefficients of mineralization-mobilization, pedotroficity, oligotrophicity were calculated in accordance with correlation of the main ecological-trophic groups of soil microorganisms. Results of soil microbiological monitoring are analyzed and generalized. Was determined that soil of natural ecosystem (natural grassland and virgin land) has highest intensity of decomposition of organic matter and was the most provided of nutrient in comparison with farmland.

  12. Role of the seasonal cycle in coupling climate and carbon cycling in the subantarctic zone

    NASA Astrophysics Data System (ADS)

    Monteiro, Pedro M. S.; Boyd, Philip; Bellerby, Richard

    2011-07-01

    Workshop on the Seasonal Cycle of the Carbon-Climate System in the Southern Ocean; Cape Town, South Africa, 23-25 August 2010; There is increasing evidence in the Southern Ocean that mesoscales and seasonal scales play an important role in the coupling of ocean carbon cycling and climate. The seasonal cycle is one of the strongest modes of variability in different components of the carbon cycle in the Southern Ocean. It is also the mode that couples climate forcing to ecosystem responses such as productivity and ultimately biogeochemical signals including carbon export. However, not only are these scales of coupling poorly understood, but also there appear to be important regional differences in the way they couple climate to carbon. With this as an overarching theme, a workshop in South Africa brought together scientists working in the Southern Ocean, the waters south of Australia, New Zealand, and South Africa. The importance of the Subantarctic Zone (SAZ) as a carbon sink made it an ideal system on which to focus the workshop.

  13. Shifts in Köppen-Geiger climate zones over southern Africa in relation to key global temperature goals

    NASA Astrophysics Data System (ADS)

    Engelbrecht, Christien J.; Engelbrecht, Francois A.

    2016-01-01

    Potential changes in Köppen-Geiger climate zones over southern Africa (Africa south of 22 °S) under future climate change are investigated using an ensemble of high-resolution projections of a regional climate model. The projections are performed under the A2 scenario of the Special Report on Emission Scenarios (SRES), and changes are presented for those times in the future when the increase in global average surface temperature reaches thresholds of 1, 2, and 3 °C, relative to the present-day baseline climatology. Widespread shifts in climate regimes are projected, of which the southern and eastern expansion of the hot desert and hot steppe zones is the most prominent. From occupying 33.1 and 19.4 % of southern Africa under present-day climate, these regions are projected to occupy between 47.3 and 59.7 % (hot desert zone) and 24.9 and 29.9 % (hot steppe zone) of the region in a future world where the global temperature has increased by 3 °C. The cold desert and cold steppe zones are projected to decrease correspondingly. The temperate regions of eastern South Africa, the Cape south coast, and winter rainfall region of the southwestern Cape are also projected to contract. An expansion of the hot steppe zone into the cold steppe and temperate zones may favor the intrusion of trees (and therefore the savanna biome) into the most pristine grasslands of southern Africa. However, the correlative climate-vegetation approach of using projected changes in Köppen-Geiger zones to infer future vegetation patterns is of limited value in the savanna complex of southern Africa, where complex feedbacks occur between carbon dioxide (CO2) concentrations, trees, C4 grasses, fire, and climate. The present-day temperate Cape Fynbos regime may come under increasing pressure as the encompassing temperate zone is invaded mainly from the east by the hot steppe climate regime under climate change, with the incidence of Fynbos fires also becoming more likely in a generally warmer and

  14. Local Climate Zones Classification to Urban Planning in the Mega City of São Paulo - SP, Brazil

    NASA Astrophysics Data System (ADS)

    Gonçalves Santos, Rafael; Saraiva Lopes, António Manuel; Prata-Shimomura, Alessandra

    2017-04-01

    Local Climate Zones Classification to Urban Planning in the Mega city of São Paulo - SP, Brazil Tropical megacities have presented a strong trend in growing urban. Urban management in megacities has as one of the biggest challenges is the lack of integration of urban climate and urban planning to promote ecologically smart cities. Local Climatic Zones (LCZs) are considered as important and recognized tool for urban climate management. Classes are local in scale, climatic in nature, and zonal in representation. They can be understood as regions of uniform surface cover, structure, material and human activity that have to a unique climate response. As an initial tool to promote urban climate planning, LCZs represent a simple composition of different land coverages (buildings, vegetation, soils, rock, roads and water). LCZs are divided in 17 classes, they are based on surface cover (built fraction, soil moisture, albedo), surface structure (sky view factor, roughness height) and cultural activity (anthropogenic heat flux). The aim of this study is the application of the LCZs classification system in the megacity of São Paulo, Brazil. Located at a latitude of 23° 21' and longitude 46° 44' near to the Tropic of Capricorn, presenting humid subtropical climate (Cfa) with diversified topographies. The megacity of São Paulo currently concentrates 11.890.000 inhabitants is characterized by large urban conglomerates with impermeable surfaces and high verticalization, having as result high urban heat island intensity. The result indicates predominance in urban zones of Compact low-rise, Compact Mid-rise, Compact High-rise and Open Low-rise. Non-urban regions are mainly covered by dense vegetation and water. The LCZs classification system promotes significant advantages for climate sensitive urban planning in the megacity of São Paulo. They offers new perspectives to the management of temperature and urban ventilation and allows the formulation of urban planning

  15. Northwest U.S. agriculture in a changing climate: collaboratively defined research and extension priorities

    Treesearch

    Georgine G. Yorgey; Sonia A. Hall; Elizabeth R. Allen; Elizabeth M. Whitefield; Nichole M. Embertson; Vincent P. Jones; Brooke R. Saari; Kirti Rajagopalan; Gabrielle E. Roesch-McNally; Beatrice Van Horne; John T. Abatzoglou; Harold P. Collins; Laurie L. Houston; Timothy W. Ewing; Chad E. Kruger

    2017-01-01

    In order for agricultural systems to successfully mitigate and adapt to climate change there is a need to coordinate and prioritize next steps for research and extension. This includes focusing on “win-win” management practices that simultaneously provide short-term benefits to farmers and improve the sustainability and resiliency of agricultural systems with respect...

  16. Climate variability and environmental stress in the Sudan-Sahel zone of West Africa.

    PubMed

    Mertz, Ole; D'haen, Sarah; Maiga, Abdou; Moussa, Ibrahim Bouzou; Barbier, Bruno; Diouf, Awa; Diallo, Drissa; Da, Evariste Dapola; Dabi, Daniel

    2012-06-01

    Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic changes and their perceptions were compared across north-south and west-east rainfall gradients. More than 80% of all households found that rainfall had decreased, especially in the wettest areas. Increases in wind speeds and temperature were perceived by an overall 60-80% of households. Contrary to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources, vegetation, and fauna, but more so in the 500-900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region, especially in the 500-900 mm zones and the western part of SSWA.

  17. Plasmodium vivax malaria: a re-emerging threat for temperate climate zones?

    PubMed

    Petersen, Eskild; Severini, Carlo; Picot, Stephane

    2013-01-01

    Plasmodium vivax was endemic in temperate areas in historic times up to the middle of last century. Temperate climate P. vivax has a long incubation time of up to 8-10 months, which partly explain how it can be endemic in temperate areas with a could winter. P. vivax disappeared from Europe within the last 40-60 years, and this change was not related to climatic changes. The surge of P. vivax in Northern Europe after the second world war was related to displacement of refugees and large movement of military personnel exposed to malaria. Lately P. vivax has been seen along the demilitarized zone in South Korea replication a high endemicity in North Korea. The potential of transmission of P. vivax still exist in temperate zones, but reintroduction in a larger scale of P. vivax to areas without present transmission require large population movements of P. vivax infected people. The highest threat at present is refugees from P. vivax endemic North Korea entering China and South Korea in large numbers.

  18. Regional climate change scenarios applied to viticultural zoning in Mendoza, Argentina

    NASA Astrophysics Data System (ADS)

    Cabré, María Fernanda; Quénol, Hervé; Nuñez, Mario

    2016-09-01

    regions. It has been concluded that regional climate change simulations are an adequate methodology, and indeed, the MM5 regional model is an appropriate tool to be applied in viticultural zoning in Mendoza, Argentina.

  19. Regional climate change scenarios applied to viticultural zoning in Mendoza, Argentina.

    PubMed

    Cabré, María Fernanda; Quénol, Hervé; Nuñez, Mario

    2016-09-01

    regions. It has been concluded that regional climate change simulations are an adequate methodology, and indeed, the MM5 regional model is an appropriate tool to be applied in viticultural zoning in Mendoza, Argentina.

  20. Defining metrics of the Quasi-Biennial Oscillation in global climate models

    NASA Astrophysics Data System (ADS)

    Schenzinger, Verena; Osprey, Scott; Gray, Lesley; Butchart, Neal

    2017-06-01

    As the dominant mode of variability in the tropical stratosphere, the Quasi-Biennial Oscillation (QBO) has been subject to extensive research. Though there is a well-developed theory of this phenomenon being forced by wave-mean flow interaction, simulating the QBO adequately in global climate models still remains difficult. This paper presents a set of metrics to characterize the morphology of the QBO using a number of different reanalysis datasets and the FU Berlin radiosonde observation dataset. The same metrics are then calculated from Coupled Model Intercomparison Project 5 and Chemistry-Climate Model Validation Activity 2 simulations which included a representation of QBO-like behaviour to evaluate which aspects of the QBO are well captured by the models and which ones remain a challenge for future model development.

  1. Chitinolytic and pectinolytic community of soils and terrestrial ecosystems of different climatic zones

    NASA Astrophysics Data System (ADS)

    Lukacheva, Evgeniya; Manucharova, Natalia

    2014-05-01

    Structural and functional features of the complex microbial degradation of biopolymers one of the most important direction in microbial ecology. But there is no a lot of data concerns degradation in vertical structure of terrestrial ecosystems. Microbial complexes of natural areas were analyzed only as humus horizons (A1) of the soil profile. Only small part of microbial community could be studied with this approach. The breakdown of chitin and pectin was studied. The aim was to provide a characterization of microorganisms involved in chitin and pectin degradation in the soils and terrestrial ecosystems in different climatic zones: steppe zone, deciduous forests and taiga. Samples of leaves, soils and litter were studied and compared. Quantity of eukaryote and procaryote organisms increased in samples with chitin and pectin comparing with control samples. Increasing of eukaryote in samples with pectin was more then in samples with chitin. Also should be noted the significant increasing of actinomycet's quantity in the samples with chitin in comparison with samples with pectin. Further prokaryote community was investigated by method FISH (fluorescence in situ hybridization). FISH is a cytogenetic technique developed that is used to detect and localize the presence or absence of specific DNA sequences on chromosomes. Quantity of Actinomycets and Firmicures was the largest among identified cells with metabolic activity in both types of the samples. Should be noted significant increasing of the quantity of Acidobateria and Bacteroidetes in pectinolytic community and Alphaproteobacteria in chitinolytic community soils. The difference between climatic zones was studied and the mathematical model was created. The mathematic model could be use in different aims, such as prognosis of microbial community composition and their classification.

  2. Environmental Survival of Mycobacterium avium subsp. paratuberculosis in Different Climatic Zones of Eastern Australia

    PubMed Central

    Begg, Douglas J.; Dhand, Navneet K.; Watt, Bruce; Whittington, Richard J.

    2014-01-01

    The duration of survival of both the S and C strains of Mycobacterium avium subsp. paratuberculosis in feces was quantified in contrasting climatic zones of New South Wales, Australia, and detailed environmental temperature data were collected. Known concentrations of S and C strains in feces placed on soil in polystyrene boxes were exposed to the environment with or without the provision of shade (70%) at Bathurst, Armidale, Condobolin, and Broken Hill, and subsamples taken every 2 weeks were cultured for the presence of M. avium subsp. paratuberculosis. The duration of survival ranged from a minimum of 1 week to a maximum of 16 weeks, and the provision of 70% shade was the most important factor in extending the survival time. The hazard of death for exposed compared to shaded samples was 20 and 9 times higher for the S and C strains, respectively. Site did not affect the survival of the C strain, but for the S strain, the hazard of death was 2.3 times higher at the two arid zone sites (Broken Hill and Condobolin) than at the two temperate zone sites (Bathurst and Armidale). Temperature measurements revealed maximum temperatures exceeding 60°C and large daily temperature ranges at the soil surface, particularly in exposed boxes. PMID:24463974

  3. Environmental survival of Mycobacterium avium subsp. paratuberculosis in different climatic zones of eastern Australia.

    PubMed

    Eppleston, Jeffrey; Begg, Douglas J; Dhand, Navneet K; Watt, Bruce; Whittington, Richard J

    2014-04-01

    The duration of survival of both the S and C strains of Mycobacterium avium subsp. paratuberculosis in feces was quantified in contrasting climatic zones of New South Wales, Australia, and detailed environmental temperature data were collected. Known concentrations of S and C strains in feces placed on soil in polystyrene boxes were exposed to the environment with or without the provision of shade (70%) at Bathurst, Armidale, Condobolin, and Broken Hill, and subsamples taken every 2 weeks were cultured for the presence of M. avium subsp. paratuberculosis. The duration of survival ranged from a minimum of 1 week to a maximum of 16 weeks, and the provision of 70% shade was the most important factor in extending the survival time. The hazard of death for exposed compared to shaded samples was 20 and 9 times higher for the S and C strains, respectively. Site did not affect the survival of the C strain, but for the S strain, the hazard of death was 2.3 times higher at the two arid zone sites (Broken Hill and Condobolin) than at the two temperate zone sites (Bathurst and Armidale). Temperature measurements revealed maximum temperatures exceeding 60°C and large daily temperature ranges at the soil surface, particularly in exposed boxes.

  4. Analysis of Radiant Cooling System Configurations Integrated with Cooling Tower for Different Indian Climatic Zones

    SciTech Connect

    Mathur, Jyotirmay; Bhandari, Mahabir S; Jain, Robin; Srivastava, Prateek

    2016-01-01

    Radiant cooling system has proven to be a low energy consumption system for building cooling needs. This study describes the use of cooling tower in radiant cooling system to improve the overall system efficiency. A comprehensive simulation feasibility study of the application of cooling tower in radiant cooling system was performed for the fifteen cities in different climatic zones of India. It was found that in summer, the wet bulb temperature (WBT) of the different climatic zones except warm-humid is suitable for the integration of cooling tower with radiant cooling system. In these climates, cooling tower can provide on average 24 C to 27 C water In order to achieve the energy saving potential, three different configurations of radiant cooling system have been compared in terms of energy consumption. The different configurations of the radiant cooling system integrated with cooling tower are: (1) provide chilled water to the floor, wall and ceiling mounted tubular installation. (2) provide chilled water to the wall and ceiling mounted tabular installation. In this arrangement a separate chiller has also been used to provide chilled water at 16 C to the floor mounted tubular installation. (3) provide chilled water to the wall mounted tabular installation and a separate chiller is used to provide chilled water at 16 C to the floor and ceiling mounted tabular installation. A dedicated outdoor air system is also coupled for dehumidification and ventilation in all three configurations. A conventional all-air system was simulated as a baseline to compare these configurations for assessing the energy saving potential.

  5. Attributing the effects of climate on phenology change suggests high sensitivity in coastal zones

    NASA Astrophysics Data System (ADS)

    Seyednasrollah, B.; Clark, J. S.

    2015-12-01

    The impact of climate change on spring phenology depends on many variables that cannot be separated using current models. Phenology can influence carbon sequestration, plant nutrition, forest health, and species distributions. Leaf phenology is sensitive to changes of environmental factors, including climate, species composition, latitude, and solar radiation. The many variables and their interactions frustrate efforts to attribute variation to climate change. We developed a Bayesian framework to quantify the influence of environment on the speed of forest green-up. This study presents a state-space hierarchical model to infer and predict change in forest greenness over time using satellite observations and ground measurements. The framework accommodates both observation and process errors and it allows for main effects of variables and their interactions. We used daily spaceborne remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) to quantify temporal variability in the enhanced vegetation index (EVI) along a habitat gradient in the Southeastern United States. The ground measurements of meteorological parameters are obtained from study sites located in the Appalachian Mountains, the Piedmont and the Atlantic Coastal Plain between years 2000 and 2015. Results suggest that warming accelerates spring green-up in the Coastal Plain to a greater degree than in the Piedmont and Appalachian. In other words, regardless of variation in the timing of spring onset, the rate of greenness in non-coastal zones decreases with increasing temperature and hence with time over the spring transitional period. However, in coastal zones, as air temperature increases, leaf expansion becomes faster. This may indicate relative vulnerability to warming in non-coastal regions where moisture could be a limiting factor, whereas high temperatures in regions close to the coast enhance forest physiological activities. Model predictions agree with the remotely

  6. A systems approach to understanding subarctic critical zone changes in a warming climate (Invited)

    NASA Astrophysics Data System (ADS)

    Rich, V. I.; McCalley, C. K.; Woodcroft, B. J.; Kim, E.; Hodgkins, S. B.; Tfaily, M. M.; Wehr, R. A.; Logan, T.; Jones, R.; Mondav, R.; Hurst, G.; Verberkmoes, N.; Li, C.; Frolking, S. E.; Crill, P. M.; Chanton, J.; Saleska, S. R.; Tyson, G. W.

    2013-12-01

    Climate change is dramatically altering the subarctic and Arctic Critical Zone. Permafrost, which currently holds approximately one third of global soil carbon in a relatively unavailable form, is predicted to be virtually eliminated by the end of the century. One endpoint for permafrost habitat thaw is wetlands, which are a major source of the microbially-produced greenhouse gas methane. This creates a potentially large positive feedback to climate change. Our team is using a systems approach spanning diverse geochemical (high-resolution greenhouse gas isofluxes and soil/peat geochemistry) and molecular (16S rRNA gene amplicon, metagenomic and metaproteomic sequencing) measurements to track parallel changes in carbon cycling and in situ microbiology across a natural permafrost thaw gradient. Thaw at this site results in a three-stage habitat shift from ericaceous shrubs, to peat moss, to sedges, concomitant with a substantial increase in methane emissions. Isotopically, emitted methane shifts along the thaw gradient away from hydrogenotrophic methane production, in parallel with the appearance of acetoclastic methanogens in the microbial community. Community data have also revealed the presence of a novel, highly-active methanogen from the euryarchaeal lineage Rice Cluster-II, dubbed Candidatus Methanoflorens stordalenmirensis. Its ';species' is present in numerous other global wetland datasets, has the genomic capacity (inferred from its population genome) for hydrogenotrophic methanogenesis, and was the highest environmental correlate of emitted methane's isotopic signature. In situ community global protein expression profiles (i.e. metaproteomes) revealed that it strongly expresses its hydrogentrophic methanogensis genes, and that methanogenesis is a dominant signal in the overall community proteome. As we generate a portrait of how thaw impacts this major subarctic critical zone habitat, we are working with ecosystem process modelers to integrate new

  7. Defining global syndromes of fire and the relationship of these to biomes, climate and human activity

    NASA Astrophysics Data System (ADS)

    Lehmann, C.; Archibald, S.; Gomez-Dans, J.; Bradstock, R.

    2012-12-01

    Fire is a ubiquitous component of the Earth system that remains poorly understood. To date, global scale understanding of fire is limited largely to the annual extent of burning as detected by satellites. This is problematic because fire is multi-dimensional, and focus on individual metrics belies both the complexity and importance of fire within the Earth system. In an applied sense, the lack of a unified understanding of fire impedes estimation of GHG emissions or prediction of future fire regimes as a consequence of changing patterns of climate and land use. To address this we identified five key characteristics of fire regimes: size, frequency, intensity, season and extent. We combined new global datasets with existing datasets to examine cross-correlations among characteristics. We demonstrate that only certain combinations of fire characteristics are possible and this likely reflects fundamental energetic constraints derived from interactions between under-lying fuel types, climate and rates of re-growth post-fire. For example, very intense fires can only occur infrequently because a system requires a lengthy period to develop sufficient fuel to burn. Further, very cool fires only occur infrequently because fuels are not available to burn. Following, we applied a clustering algorithm to these data to determine whether we could identify syndromes of fire regimes. Pyromes, as global syndromes of fire are conceptually analogous to biomes (global syndromes of vegetation) where the extent of each pyrome is determined solely as a product of the fire characteristics themselves. A point of difference to biomes being that no one has previously attempted to quantify the global range of fire syndromes. We identified five pyromes, four of which we believe represent distinctions between crown, litter and grass-fuelled fires. The relationship of pyromes to biomes and climate are not deterministic as different biomes and climates may be represented within a single pyrome

  8. Defining climate modeling user needs: which data are actually required to support impact analysis and adaptation policy development?

    NASA Astrophysics Data System (ADS)

    Swart, R. J.; Pagé, C.

    2010-12-01

    Until recently, the policy applications of Earth System Models in general and climate models in particular were focusing mainly on the potential future changes in the global and regional climate and attribution of observed changes to anthropogenic activities. Is climate change real? And if so, why do we have to worry about it? Following the broad acceptance of the reality of the risks by the majority of governments, particularly after the publication of IPCC’s 4th Assessment Report and the increasing number of observations of changes in ecological and socio-economic systems that are consistent with the observed climatic changes, governments, companies and other societal groups have started to evaluate their own vulnerability in more detail and to develop adaptation and mitigation strategies. After an early focus on the most vulnerable developing countries, recently, an increasing number of industrialized countries have embarked on the design of adaptation and mitigation plans, or on studies to evaluate the level of climate resilience of their development plans and projects. Which climate data are actually required to effectively support these activities? This paper reports on the efforts of the IS-ENES project, the infrastructure project of the European Network for Earth System Modeling, to address this question. How do we define user needs and can the existing gap between the climate modeling and impact research communities be bridged in support of the ENES long-term strategy? In contrast from the climate modeling community, which has a relatively long history of collaboration facilitated by a relatively uniform subject matter, commonly agreed definitions of key terminology and some level of harmonization of methods, the climate change impacts research community is very diverse and fragmented, using a wide variety of data sources, methods and tools. An additional complicating factor is that researchers working on adaptation usually closely collaborate with non

  9. How Soil Water Storage Moderates Climate Change's Effects on Transpiration Across the Critical Zone Observatories

    NASA Astrophysics Data System (ADS)

    Heckman, C.; Tague, N.

    2016-12-01

    While the atmospheric water demand is predicted to increase under a warmer climate, actual evapotranspiration (AET) will be moderated by the supply of water available to vegetation. A key question is how will plant accessible water storage capacity (PAWSC) effect the partitioning of precipitation between AET and runoff. Our results indicate that whether and by how much AET increases or decreases with moderate warming is significantly based upon interactions between PAWSC and characteristics of precipitation such as the amount, frequency, and skew as well the partitioning between rain and snow. In snow dominated climates, if PAWSC cannot make up for the loss of storage as snowpack then AET may decrease despite warming temperatures. Even in rain dominated climates, PAWSC could significantly limit the increase in AET associated with higher atmospheric demand. Changes in AET will have significant impacts for forests vulnerability to drought, insect out breaks, and fire as well as for the amount of runoff that flows downstream for our use and management. Due to the highly heterogeneous nature of PAWSC and the difficulty of measuring it across large scales, we use a well-tested hydrologic model to estimate the impacts from a range of PAWSC on the partitioning of precipitation between runoff and AET. We completed this analysis for the range of precipitation and vegetation characteristics found across the 9 Critical Zone Observatories of the United States.

  10. Water-Vegetation Interaction in Mediterranean Climate Zones Under Global Warming

    NASA Astrophysics Data System (ADS)

    Krakauer, N. Y.; Fung, I. F.

    2006-12-01

    Water shortage controls biotic production over much of the land surface. Global warming will exacerbate water limitation in arid and semiarid areas, but high CO2 concentrations should increase plant water use efficiency; the net impact on vegetation productivity and water availability is uncertain. We analyzed the response of vegetation to historic and future (SRES A2) fossil CO2 emissions in the Climate System Model (CSM1.4) run with coupled ocean, atmosphere and land-surface components, focusing on areas with a Mediterranean climate (defined by the occurrence of precipitation mostly during the cool season, with consequent summer drought). By the 2090s, Mediterranean regions were modeled to have warmed by almost 1 {°}C more than the land surface average. Precipitation increased modestly, while NPP rose by more than the world average possibly because of warmer conditions in the spring growing season, but mean water vapor pressure deficits increased and water use efficiency fell slightly despite the favorable impact of high CO2. More work is needed to understand the contribution of vegetation responses to regional climate change, and to test the process mechanisms assumed in climate models.

  11. Prevalence of Toxocara spp., Toxascaris leonina and ancylostomidae in public parks and beaches in different climate zones of Costa Rica.

    PubMed

    Paquet-Durand, Isabelle; Hernández, J; Dolz, G; Zuñiga, J J Romero; Schnieder, T; Epe, C

    2007-10-01

    This epidemiological study was conducted in different regions of Costa Rica to determine the prevalence of the developmental stages of potential zoonotic intestinal helminths of dogs and cats in public places. Samples were collected within three main climate zones including rural and urban areas during both the rainy and the dry season. Faecal and environmental samples were taken from 69 parks and beaches. Of the faecal samples 3% contained Toxascaris spp. eggs, 7% Toxocara spp. eggs and 55% contained ancylostomidae eggs. Of the soil samples, 2% contained ancylostomidae eggs and 0.8% contained ascarid eggs. Significant differences in the presence of parasites were found in faecal samples of dry, moist and wet climate zones and between the dry and rainy seasons. Significant differences in the presence of eggs and larvae were also found in the grass samples in the dry, the moist and the wet climate zones and between the different seasons. No significant differences were found between rural and urban areas.

  12. [Correlation analysis between meteorological factors, biomass, and active components of Salvia miltiorrhiza in different climatic zones].

    PubMed

    Zhang, Chen-lu; Liang, Zong-suo; Guo, Hong-bo; Liu, Jing-ling; Liu, Yan; Liu, Feng-hua; Wei, Lang-zhu

    2015-02-01

    In this study, the growth and accumulation of active components of Salvia miltiorrhiza in twenty two experimental sites which crossing through three typical climate zones. The S. miltiorrhiza seedlings with the same genotype were planted in each site in spring, which were cultivated in fields with uniform management during their growing seasons till to harvest. The diterpene ketones (dihydrotanshinone, cryptotanshinone, tanshinone I and tanshinone II(A)) in S. miltiorrhiza root samples were determined by using high-performance liquid chromatography (HPLC) method. The biomass of root (root length, number of root branches, root width and dry weight) was also measured. The results showed that tanshinone II(A) in all samples of each site were higher than the standards required by China Pharmacopoeia. It has been found there is a relationship between root shape and climate change. The correlation analysis between active components and meteorological factors showed that the accumulation of tanshinones were effected by such meteorological factors as average relative humidity from April to October > average vapor pressure from April to October > average temperature difference day and night from April to October > annual average temperature and so on. The correlation analysis between root biomass and meteorological factors exhibited that root shape and accumulation of dry matter were affected by those factors, such as average annual aboveground (0-20 cm) temperature from April to October > annual average temperature > average vapor pressure from April to October > annual active accumulated temperature > annual average temperature > average vapor pressure from April to October. The accumulation of tanshinones and biomass was increased with the decrease of latitude. At the same time, the dry matter and diameter of root decreased if altitude rises. In addition, S. miltiorrhiza required sunlight is not sophisticated, when compared with humid and temperature. To sum up, S

  13. Comparative transcriptome analysis of ginger variety Suprabha from two different agro-climatic zones of Odisha.

    PubMed

    Gaur, Mahendra; Das, Aradhana; Sahoo, Rajesh Kumar; Mohanty, Sujata; Joshi, Raj Kumar; Subudhi, Enketeswara

    2016-09-01

    Ginger (Zingiber officinale Rosc.), a well-known member of family Zingiberaceae, is bestowed with number of medicinal properties which is because of the secondary metabolites, essential oil and oleoresin, it contains in its rhizome. The drug yielding potential is known to depend on agro-climatic conditions prevailing at the place cultivation. Present study deals with comparative transcriptome analysis of two sample of elite ginger variety Suprabha collected from two different agro-climatic zones of Odisha. Transcriptome assembly for both the samples was done using next generation sequencing methodology. The raw data of size 10.8 and 11.8 GB obtained from analysis of two rhizomes S1Z4 and S2Z5 collected from Bhubaneswar and Koraput and are available in NCBI accession number SAMN03761169 and SAMN03761176 respectively. We identified 60,452 and 54,748 transcripts using trinity tool respectively from ginger rhizome of S1Z4 and S2Z5. The transcript length varied from 300 bp to 15,213 bp and 8988 bp and N50 value of 1415 bp and 1334 bp respectively for S1Z4 and S2Z5. To the best of our knowledge, this is the first comparative transcriptome analysis of elite ginger cultivars Suprabha from two different agro-climatic conditions of Odisha, India which will help to understand the effect of agro-climatic conditions on differential expression of secondary metabolites.

  14. Comparing Mid-Century Climate Change Projections at Convective Resolving Scales (2-km) for Life Zones Within Puerto Rico

    NASA Astrophysics Data System (ADS)

    Bowden, J.; Wootten, A.; Terando, A. J.; Boyles, R.; Misra, V.; Bhardwaj, A.

    2016-12-01

    Puerto Rico is home to over 3.5 million people and numerous endemic plant and animal species that may be at risk as a result of anthropogenic climate change. This study downscales three CMIP5 Global Circulation Models (GCMs) to a 2-km horizontal resolution using different regional climate models (RCMs) to resolve the island's climate. Here we compare projected climate change from a single GCM, CCSM4, from two RCMs centered on the mid-century, 2041-2060, for a high greenhouse gas emission scenario, RCP8.5. We will discuss similarities and differences in ecologically relevant climate variables, which were selected based on dialogue with experts who have knowledge about potential biological impacts of climate change for current life zones within Puerto Rico. Notable differences appear between the RCMs and include regions with critical ecosystems, such as the El Yunque National Forest in northeast Puerto Rico. This study helps to highlight RCMs structural uncertainty at convective resolving scales.

  15. Influence of hydro-climatic conditions, soil type, and application matrix on potential vadose zone export of PPCPs

    NASA Astrophysics Data System (ADS)

    Gall, H. E.; Rao, P.; O'Connor, G.

    2013-12-01

    The land-application of biosolids and animal manure to agricultural fields has the potential to negatively impact the quality of nearby surface and subsurface water due to the presence of emerging contaminants in these residuals. We investigated the extent to which the vadose zone acts as a hydrologic and biogeochemical filter of two emerging contaminants, Triclosan (TCS) and estrone (E1) using a coupled source zone and vadose zone modeling approach. Monte Carlo simulations were run for a year following residual applications to explore the following research questions: (1) how does the application matrix (e.g., de-watered solids, liquid lagoon effluent, etc.) affect PPCP mass fluxes?; (2) how do hydro-climatic conditions and soil type affect PPCP mass fluxes?; (3) what role does the presence of macropore pathways play in PPCP export from the vadose zone; and (4) does the long-term, repeated application of residuals affect the ability of the vadose zone to act as an effective biogeochemical filter? The simulations were conducted for a sub-tropical climate with sand (e.g., Florida) and a humid climate with a silty clay loam (e.g., Midwestern United States). Simulation results suggest that the potential mobility of emerging contaminants increases linearly with increasing fraction applied to the mobile phase of the source zone (i.e., higher PPCP mass fraction in the dissolved phase during application). Following a single application, the total amount of PPCP mass exported from the source zone over the course of a year can be as high as 70% in a sub-tropical climate with sand soil. However, these types of soils do not have macropore flow pathways and the annual PPCP mass exported from the vadose zone is less than 1% of the mass applied. The higher organic carbon content in a silty clay loam reduces the amount of PPCP mass released from the source zone to less than 5% of the mass applied. In the presence of macropore pathways, the silty clay loam's vadose zone acts as a

  16. Climate change, agroclimatic resources and agroclimatic zoning of agriculture in Bulgaria

    NASA Astrophysics Data System (ADS)

    Kazandjiev, V.; Moteva, M.; Georgieva, V.

    2009-09-01

    The important factors for the agrarian output in Bulgaria are only thermal and water probability. From the two factors the component related to soil moisture is more limited. As well water and temperatures probabilities in the agrarian output are estimated trough sums of temperatures and rainfalls or by derivatives indicators (most frequently named as coefficients or indices). The heat conditions and the heat resources are specified by the continuousness of the vegetative period. Duration of vegetative season is limited for each type of plant, between the spring and autumn steady pass of air temperature across the biological minimum. For the agricultural crops in Bulgaria the three biological minimums: in 5°C are taken for wheat and barley, oat, pea, lentil and sunflower; 10°C for corn, haricot, and soybean and in 15°C for the cotton, vegetables and other spring cultures). The cold and warm period duration are mutually related characteristics. The first period define number of days with the snow fall and days with the snow cover, that are in the basis in the formation of soil moisture reserves after the spring snow melt. Definition of the regions with temperature stress conditions during vegetative season is one of the most important parameters of agroclimatic conditions. The values indicating for the limitations are one or more periods from at least 10 consecutive days with maximal air temperature over 35 °С. More from the agricultures, character for the moderate continental climatic zone are developed normally under temperatures 25-28°С. Temperatures over 28°C are ballast slowing the growth and destroying plants due to the heat tension. The component, limiting in greatest degree growth, development and formation of yields from the agricultural crops are the conditions of moisturizing, present trough atmospheric and soil moisture. The most apparent indicator is the year sum of the rains or their sum by the periods with the average daily temperatures of

  17. Harnessing the agricultural critical zone for climate change mitigation through enhanced rock weathering with croplands

    NASA Astrophysics Data System (ADS)

    Beerling, D. J.; Taylor, L.; Banwart, S. A.; Kantzas, E. P.; Kelland, M.; Leake, J.; Lomas, M.; Mueller, C.; Hodson, M.; Ridgwell, A.; Quegan, S.

    2016-12-01

    In an agricultural context, enhanced rock weathering resulting from the application of crushed silicates to soils is driven by climate and photosynthate energy exported by crops below ground to roots and their associated mycorrhizal partners. Detailed mechanisms involved are increasingly well resolved for natural soils but not for agriculturally managed soils supplemented with crushed silicates. Assessment of the potential of the approach is made first with controlled environment studies using the mycorrhizal C4 crop sorghum grown in agricultural soil with and without the addition of crushed basalt. We then extend these findings with simulations capturing regional-to-global rates of enhanced basalt weathering by root system-microbial processes for the major crop functional types. Resulting global carbon cycle simulations indicate significant capacity for sequestering anthropogenic CO2 emissions through manipulating the agricultural critical zone in this way with multiple co-benefits, including remediating acidic soils, fertilization of crop production and crop protection from herbivores and biotrophs.

  18. Vulnerability of boreal zone for increased nitrogen loading due to climate change

    NASA Astrophysics Data System (ADS)

    Rankinen, Katri; Holmberg, Maria

    2016-04-01

    The observed rapid warming of the boreal zone that has been observed in Finland (0.14 °C by decade) is expected to continue (http://www.ipcc.ch/report/ar5/wg1/). Also precipitation is assumed to increase in future. These changes may increase nitrogen (N) loading from terrestrial environments to water bodies by accelerating soil organic matter decay and by increasing runoff. Nitrogen is limiting nutrient in the Baltic Sea but also in some lakes, so increased loading may increase eutrophication. Further, high nitrate levels in drinking water may cause methaemoglobin anemia for humans, and nitrate is also connected to increased risk of diabetes and cancer. Thus EU has set upper limits to nitrate concentration in drinking water. MONIMET (LIFE12 ENV/FI/000409) is a project about Climate Change Indicators and Vulnerability of Boreal Zone. We simulated N loading from two boreal catchments to the receiving waters by the dynamic, catchment scale model INCA in different climate change and land use change scenarios. We calculated land use specific N loading values for these two well monitored catchments that belong to the LTER (The Long Term Ecological Research) monitoring network. We upscaled the results to the larger river basin, combining them with the information on drinking water supply to assess the vulnerability. Specific emphasis was paid on nitrate concentrations in soil water and groundwater. In general, land use change has higher influence on N loading than increase in precipitation and temperature alone. Peak runoff will sift from snow melting peak in April to late autumn and winter. Growing season will become longer allowing more efficient vegetation uptake of nutrients. Small groundwater aquifers and private wells in the middle of agricultural fields will be in the risk of increased N concentrations, if agricultural N loading increases due to changes in agricultural patterns and land use change.

  19. Influence of neighbourhood information on 'Local Climate Zone' mapping in heterogeneous cities

    NASA Astrophysics Data System (ADS)

    Verdonck, Marie-Leen; Okujeni, Akpona; van der Linden, Sebastian; Demuzere, Matthias; De Wulf, Robert; Van Coillie, Frieke

    2017-10-01

    Local climate zone (LCZ) mapping is an emerging field in urban climate research. LCZs potentially provide an objective framework to assess urban form and function worldwide. The scheme is currently being used to globally map LCZs as a part of the World Urban Database and Access Portal Tools (WUDAPT) initiative. So far, most of the LCZ maps lack proper quantitative assessment, challenging the generic character of the WUDAPT workflow. Using the standard method introduced by the WUDAPT community difficulties arose concerning the built zones due to high levels of heterogeneity. To overcome this problem a contextual classifier is adopted in the mapping process. This paper quantitatively assesses the influence of neighbourhood information on the LCZ mapping result of three cities in Belgium: Antwerp, Brussels and Ghent. Overall accuracies for the maps were respectively 85.7 ± 0.5, 79.6 ± 0.9, 90.2 ± 0.4%. The approach presented here results in overall accuracies of 93.6 ± 0.2, 92.6 ± 0.3 and 95.6 ± 0.3% for Antwerp, Brussels and Ghent. The results thus indicate a positive influence of neighbourhood information for all study areas with an increase in overall accuracies of 7.9, 13.0 and 5.4%. This paper reaches two main conclusions. Firstly, evidence was introduced on the relevance of a quantitative accuracy assessment in LCZ mapping, showing that the accuracies reported in previous papers are not easily achieved. Secondly, the method presented in this paper proves to be highly effective in Belgian cities, and given its open character shows promise for application in other heterogeneous cities worldwide.

  20. Factors influencing smallholder farmers' behavioural intention towards adaptation to climate change in transitional climatic zones: A case study of Hwedza District in Zimbabwe.

    PubMed

    Zamasiya, Byron; Nyikahadzoi, Kefasi; Mukamuri, Billy Billiard

    2017-08-01

    This paper examines factors influencing behavioural change among smallholder farmers towards adaptation to climate change in transitional climatic zones of Africa, specifically, Hwedza District in Zimbabwe. Data for this study were collected from 400 randomly-selected smallholder farmers, using a structured questionnaire, focus group discussions and key informant interviews. The study used an ordered logit model to examine the factors that influence smallholder farmers' behavioural intention towards adaptation to climate change. Results from the study show that the gender of the household head, access to extension services on crop and livestock production, access to climate information, membership to social groups and experiencing a drought have a positive influence on farmers' attitude towards adaptation to climate change and variability. The study concluded that although the majority of smallholder farmers perceive that the climate is changing, they continue to habour negative attitudes towards prescribed climate change adaptation techniques. This study recommends more education on climate change, as well as adaptation strategies for both agricultural extension workers and farmers. This can be complemented by disseminating timely climate information through extension officers and farmers' groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Recovery of coastal ecosystems after large tsunamis in various climatic zones - review of cases from tropical, temperate and polar zones (Invited)

    NASA Astrophysics Data System (ADS)

    Szczucinski, W.

    2013-12-01

    Large tsunamis cause significant changes in coastal ecosystems. They include modifications in shoreline position, sediment erosion and deposition, new initial soil formation, salination of soils and waters, removal of vegetation, as well as direct impact on humans and infrastructure. The processes and rate of coastal zone recovery from large tsunamis has been little studied but during the last decade a noteworthy progress has been made. This study focus on comparison of recovery processes in various climatic zones, namely in monsoonal-tropical, temperate and polar zone. It is based on own observation and monitoring in areas affected by 2004 Indian Ocean Tsunami in Thailand, 2011 Tohoku-oki tsunami in Japan and 2000 Paatuut landslide-generated tsunami in Vaigat Strait (west Greenland), as well as on review of published studies from those areas. The particular focus is on physical and biological recoveries of beaches, recovery of coastal vegetation, new soil formation in eroded areas and those covered by tsunami deposits, marine salt removal from soils, surface- and groundwater, as well as landscape adjustment after the tsunamis. The beach zone - typically the most tsunami-eroded zone, has been recovered already within weeks to months and has been observed to be in the pre-tsunami equilibrium stage within one year in all the climate zones, except for sediment-starved environments. The existing data on beach ecosystems point also to relatively fast recovery of meio- and macrofauna (within weeks to several months). The recovery of coastal vegetation depends on the rate of salt removal from soils or on the rate of soil formation in case of its erosion or burial by tsunami deposits. The salt removal have been observed to depend mainly on precipitation and effective water drainage. In tropical climate with seasonal rainfall of more 3000 mm the salt removal was fast, however, in temperate climate with lower precipitation and flat topography the salinities still exceeded

  2. Evaluation of outdoor human thermal sensation of local climate zones based on long-term database

    NASA Astrophysics Data System (ADS)

    Unger, János; Skarbit, Nóra; Gál, Tamás

    2017-09-01

    This study gives a comprehensive picture on the diurnal and seasonal general outdoor human thermal sensation levels in different urban quarters based on long-term (almost 3 years) data series from urban and rural areas of Szeged, Hungary. It is supplemented with a case study dealing with an extreme heat wave period which is more and more frequent in the last decades in the study area. The intra-urban comparison is based on a thermal aspect classification of the surface, namely, the local climate zone (LCZ) system, on an urban meteorological station network and on the utilization of the physiologically equivalent temperature (PET) comfort index with categories calibrated to the local population. The selected stations represent sunlit areas well inside the LCZ areas. The results show that the seasonal and annual average magnitudes of the thermal load exerted by LCZs in the afternoon and evening follow their LCZ numbers. It is perfectly in line with the LCZ concept originally concentrating only on air temperature (T air) differences between the zones. Our results justified the subdivision of urban areas into LCZs and give significant support to the application possibilities of the LCZ concept as a broader term covering different thermal phenomena.

  3. European Regional Climate Zone Modeling of a Commercial Absorption Heat Pump Hot Water Heater

    SciTech Connect

    Sharma, Vishaldeep; Shen, Bo; Keinath, Chris; Garrabrant, Michael A.; Geoghegan, Patrick J

    2017-01-01

    High efficiency gas-burning hot water heating takes advantage of a condensing heat exchanger to deliver improved combustion efficiency over a standard non-condensing configuration. The water heating is always lower than the gas heating value. In contrast, Gas Absorption Heat Pump (GAHP) hot water heating combines the efficiency of gas burning with the performance increase from a heat pump to offer significant gas energy savings. An ammonia-water system also has the advantage of zero Ozone Depletion Potential and low Global Warming Potential. In comparison with air source electric heat pumps, the absorption system can maintain higher coefficients of performance in colder climates. In this work, a GAHP commercial water heating system was compared to a condensing gas storage system for a range of locations and climate zones across Europe. The thermodynamic performance map of a single effect ammonia-water absorption system was used in a building energy modeling software that could also incorporate the changing ambient air temperature and water mains temperature for a specific location, as well as a full-service restaurant water draw pattern.

  4. Climate-Induced Larch Growth Response Within the Central Siberian Permafrost Zone

    NASA Technical Reports Server (NTRS)

    Kharuk, Viacheslav I.; Ranson, Kenneth J.; Im, Sergei T.; Petrov, Il'ya A.

    2015-01-01

    Aim: estimation of larch (Larix gmelinii) growth response to current climate changes. Location: permafrost area within the northern part of Central Siberia (approximately 65.8 deg N, 98.5 deg E). Method: analysis of dendrochronological data, climate variables, drought index SPEI, GPP (gross primary production) and EVI vegetation index (both Aqua/MODIS satellite derived), and soil water content anomalies (GRACE satellite measurements of equivalent water thickness anomalies, EWTA). Results: larch tree ring width (TRW) correlated with previous year August precipitation (r = 0.63), snow accumulation (r = 0.61), soil water anomalies (r = 0.79), early summer temperatures and water vapor pressure (r = 0.73 and r = 0.69, respectively), May and June drought index (r = 0.68-0.82). There are significant positive trends of TRW since late 1980s and GPP since the year 2000. Mean TRW increased by about 50%, which is similar to post-Little Ice Age warming. TRW correlated with GPP and EVI of larch stands (r = 0.68-0.69). Main conclusions: within the permafrost zone of central Siberia larch TRW growth is limited by early summer temperatures, available water from snowmelt, water accumulated within soil in the previous year, and permafrost thaw water. Water stress is one of the limiting factors of larch growth. Larch TRW growth and GPP increased during recent decades.

  5. Climatic and landscape controls on water transit times and silicate mineral weathering in the critical zone

    NASA Astrophysics Data System (ADS)

    Zapata-Rios, Xavier; McIntosh, Jennifer; Rademacher, Laura; Troch, Peter A.; Brooks, Paul D.; Rasmussen, Craig; Chorover, Jon

    2015-08-01

    The critical zone (CZ) can be conceptualized as an open system reactor that is continually transforming energy and water fluxes into an internal structural organization and dissipative products. In this study, we test a controlling factor on water transit times (WTT) and mineral weathering called Effective Energy and Mass Transfer (EEMT). We hypothesize that EEMT, quantified based on local climatic variables, can effectively predict WTT within—and mineral weathering products from—the CZ. This study tests whether EEMT or static landscape characteristics are good predictors of WTT, aqueous phase solutes, and silicate weathering products. Our study site is located around Redondo Peak, a rhyolitic volcanic resurgent dome, in northern New Mexico. At Redondo Peak, springs drain slopes along an energy gradient created by differences in terrain aspect. This investigation uses major solute concentrations, the calculated mineral mass undergoing dissolution, and the age tracer tritium and relates them quantitatively to EEMT and landscape characteristics. We found significant correlations between EEMT, WTT, and mineral weathering products. Significant correlations were observed between dissolved weathering products (Na+ and DIC), 3H concentrations, and maximum EEMT. In contrast, landscape characteristics such as contributing area of spring, slope gradient, elevation, and flow path length were not as effective predictive variables of WTT, solute concentrations, and mineral weathering products. These results highlight the interrelationship between landscape, hydrological, and biogeochemical processes and suggest that basic climatic data embodied in EEMT can be used to scale hydrological and hydrochemical responses in other sites.

  6. NDVI dynamics of the taiga zone in connection with modern climate changes

    NASA Astrophysics Data System (ADS)

    Bobkov, A.; Panidi, E.; Torlopova, N.; Tsepelev, V.

    2015-04-01

    This research is dedicated to the investigation of the relations between the XXI century climate changes and Normalized Difference Vegetation Index (NDVI) variability of the taiga zone. For this purposes was used the observations of vegetation variability on the test area located nearby Syktyvkar city (Komi Republic, Russia), 16-day averages of NDVI data derived from TERRA/MODIS space imagery (spatial resolution is about 250 meters), and the air temperature and precipitation observations from Syktyvkar meteorological station. The research results confirmed the statistically significant positive correlation between NDVI and air temperature for all vegetation types of the test area, for both spring and autumn seasons. The weakest correlation was found for coniferous forest, namely, pine forest on poor soils, and the strongest correlation was found for meadows and bogs. Additionally the map of NDVI trends of the test area shows that the sectors of greatest positive trend located on the territories with non-forest cover, and as a result, the positive trend of air temperature is indicated most brightly on vegetation of non-forest lands. Thereby these lands can serve as climate changes indicator in the investigated region. The study was partially supported by Russian Foundation for Basic Research (RFBR), research project No. 14-05-00858 a.

  7. Climate-Induced Larch Growth Response Within the Central Siberian Permafrost Zone

    NASA Technical Reports Server (NTRS)

    Kharuk, Viacheslav I.; Ranson, Kenneth J.; Im, Sergei T.; Petrov, Il'ya A.

    2015-01-01

    Aim: estimation of larch (Larix gmelinii) growth response to current climate changes. Location: permafrost area within the northern part of Central Siberia (approximately 65.8 deg N, 98.5 deg E). Method: analysis of dendrochronological data, climate variables, drought index SPEI, GPP (gross primary production) and EVI vegetation index (both Aqua/MODIS satellite derived), and soil water content anomalies (GRACE satellite measurements of equivalent water thickness anomalies, EWTA). Results: larch tree ring width (TRW) correlated with previous year August precipitation (r = 0.63), snow accumulation (r = 0.61), soil water anomalies (r = 0.79), early summer temperatures and water vapor pressure (r = 0.73 and r = 0.69, respectively), May and June drought index (r = 0.68-0.82). There are significant positive trends of TRW since late 1980s and GPP since the year 2000. Mean TRW increased by about 50%, which is similar to post-Little Ice Age warming. TRW correlated with GPP and EVI of larch stands (r = 0.68-0.69). Main conclusions: within the permafrost zone of central Siberia larch TRW growth is limited by early summer temperatures, available water from snowmelt, water accumulated within soil in the previous year, and permafrost thaw water. Water stress is one of the limiting factors of larch growth. Larch TRW growth and GPP increased during recent decades.

  8. Climate-Induced Landsliding within the Larch Dominant Permafrost Zone of Central Siberia

    NASA Technical Reports Server (NTRS)

    Kharuk, Viacheslav I.; Shushpanov, Alexandr S.; Im, Sergei T.; Ranson, Kenneth J.

    2016-01-01

    Climate impact on landslide occurrence and spatial patterns were analyzed within the larch-dominant communities associated with continuous permafrost areas of central Siberia. We used high resolution satellite imagery (i.e. QuickBird, WorldView) to identify landslide scars over an area of 62 000 km2. Landslide occurrence was analyzed with respect to climate variables (air temperature, precipitation, drought index SPEI), and Gravity Recovery and Climate Experiment satellite derived equivalent of water thickness anomalies (EWTA). Landslides were found only on southward facing slopes, and the occurrence of landslides increased exponentially with increasing slope steepness. Lengths of landslides correlated positively with slope steepness. The observed upper elevation limit of landslides tended to coincide with the tree line. Observations revealed landslides occurrence was also found to be strongly correlated with August precipitation (r = 0.81) and drought index (r = 0.7), with June-July-August soil water anomalies (i.e., EWTA, r = 0.68-0.7), and number of thawing days (i.e., a number of days with t (max) > 0 deg C; r = 0.67). A significant increase in the variance of soil water anomalies was observed, indicating that occurrence of landslides may increase even with a stable mean precipitation level. The key-findings of this study are (1) landslides occurrence increased within the permafrost zone of central Siberia in the beginning of the 21st century; (2) the main cause of increased landslides occurrence are extremes in precipitation and soil water anomalies; and (3) landslides occurrence are strongly dependent on relief features such as southward facing steep slopes.

  9. Climate-induced landsliding within the larch dominant permafrost zone of central Siberia

    NASA Astrophysics Data System (ADS)

    Kharuk, Viacheslav I.; Shushpanov, Alexandr S.; Im, Sergei T.; Ranson, Kenneth J.

    2016-04-01

    Climate impact on landslide occurrence and spatial patterns were analyzed within the larch-dominant communities associated with continuous permafrost areas of central Siberia. We used high resolution satellite imagery (i.e. QuickBird, WorldView) to identify landslide scars over an area of 62 000 km2. Landslide occurrence was analyzed with respect to climate variables (air temperature, precipitation, drought index SPEI), and Gravity Recovery and Climate Experiment satellite derived equivalent of water thickness anomalies (EWTA). Landslides were found only on southward facing slopes, and the occurrence of landslides increased exponentially with increasing slope steepness. Lengths of landslides correlated positively with slope steepness. The observed upper elevation limit of landslides tended to coincide with the tree line. Observations revealed landslides occurrence was also found to be strongly correlated with August precipitation (r = 0.81) and drought index (r = 0.7), with June-July-August soil water anomalies (i.e., EWTA, r = 0.68-0.7), and number of thawing days (i.e., a number of days with t max > 0 °C r = 0.67). A significant increase in the variance of soil water anomalies was observed, indicating that occurrence of landslides may increase even with a stable mean precipitation level. The key-findings of this study are (1) landslides occurrence increased within the permafrost zone of central Siberia in the beginning of the 21st century; (2) the main cause of increased landslides occurrence are extremes in precipitation and soil water anomalies; and (3) landslides occurrence are strongly dependent on relief features such as southward facing steep slopes.

  10. Assessment of projected climate change in the Carpathian Region using the Holdridge life zone system

    NASA Astrophysics Data System (ADS)

    Szelepcsényi, Zoltán; Breuer, Hajnalka; Kis, Anna; Pongrácz, Rita; Sümegi, Pál

    2016-11-01

    In this paper, expected changes in the spatial and altitudinal distribution patterns of Holdridge life zone (HLZ) types are analysed to assess the possible ecological impacts of future climate change for the Carpathian Region, by using 11 bias-corrected regional climate model simulations of temperature and precipitation. The distribution patterns of HLZ types are characterized by the relative extent, the mean centre and the altitudinal range. According to the applied projections, the following conclusions can be drawn: (a) the altitudinal ranges are likely to expand in the future, (b) the lower and upper altitudinal limits as well as the altitudinal midpoints may move to higher altitudes, (c) a northward shift is expected for most HLZ types and (d) the magnitudes of these shifts can even be multiples of those observed in the last century. Related to the northward shifts, the HLZ types warm temperate thorn steppe and subtropical dry forest can also appear in the southern segment of the target area. However, a large uncertainty in the estimated changes of precipitation patterns was indicated by the following: (a) the expected change in the coverage of the HLZ type cool temperate steppe is extremely uncertain because there is no consensus among the projections even in terms of the sign of the change (high inter-model variability) and (b) a significant trend in the westward/eastward shift is simulated just for some HLZ types (high temporal variability). Finally, it is important to emphasize that the uncertainty of our results is further enhanced by the fact that some important aspects (e.g. seasonality of climate variables, direct CO2 effect, etc.) cannot be considered in the estimating process.

  11. Land-Use Change Impact on Soil Sustainability in a Climate and Vegetation Transition Zone

    SciTech Connect

    Reitsma, Kurt D.; Dunn, Barry H.; Mishra, U.; Clay, Sharon A.; DeSutter, Thomas; Clay, David E.

    2015-09-11

    A growing world population and climate change are expected to influence future agricultural productivity and land use. This study determined the impact of land-use change on soil sustainability and discussed the factors contributing to these changes. South Dakota was selected as a model system because corn (Zea mays L.) grain prices tripled between 2006 and 2012 and it is located in a climate and grassland/cropland transition zone. High resolution imagery was used to visually determine land uses (cropland, grassland, nonagricultural, habitat, and water) at 14,400 points in 2006 and 2012. At each point, land-use change and the USDA land capability class (LCC) were determined. Over the 6-yr study period, 6.87% of the grasslands (730,000 ha) were converted to cropland, with 93% occurring on lands generally considered suitable for crop production (LCC ≤ IV) if appropriate practices are followed. Converted grasslands, however, had higher LCC values than existing croplands and lower LCC values than remaining grasslands. In addition, 4.2% of the croplands (250,000 ha) were converted to grasslands, and statewide, 20,000 ha of croplands were converted to grasslands in areas limited by excess water (LCC V). The conversion of grasslands could not be linked to one specific factor and may be related to: (i) a desire to increase financial returns, (ii) changes in the land ownership structure, (iii) technology improvements, (iv) governmental policies, (v) climate change, and (vi) an aging workforce. Here, research and outreach programs that balance the goods and services of different land uses are needed to maintain sustainable agroecosystems.

  12. Land-Use Change Impact on Soil Sustainability in a Climate and Vegetation Transition Zone

    DOE PAGES

    Reitsma, Kurt D.; Dunn, Barry H.; Mishra, U.; ...

    2015-09-11

    A growing world population and climate change are expected to influence future agricultural productivity and land use. This study determined the impact of land-use change on soil sustainability and discussed the factors contributing to these changes. South Dakota was selected as a model system because corn (Zea mays L.) grain prices tripled between 2006 and 2012 and it is located in a climate and grassland/cropland transition zone. High resolution imagery was used to visually determine land uses (cropland, grassland, nonagricultural, habitat, and water) at 14,400 points in 2006 and 2012. At each point, land-use change and the USDA land capabilitymore » class (LCC) were determined. Over the 6-yr study period, 6.87% of the grasslands (730,000 ha) were converted to cropland, with 93% occurring on lands generally considered suitable for crop production (LCC ≤ IV) if appropriate practices are followed. Converted grasslands, however, had higher LCC values than existing croplands and lower LCC values than remaining grasslands. In addition, 4.2% of the croplands (250,000 ha) were converted to grasslands, and statewide, 20,000 ha of croplands were converted to grasslands in areas limited by excess water (LCC V). The conversion of grasslands could not be linked to one specific factor and may be related to: (i) a desire to increase financial returns, (ii) changes in the land ownership structure, (iii) technology improvements, (iv) governmental policies, (v) climate change, and (vi) an aging workforce. Here, research and outreach programs that balance the goods and services of different land uses are needed to maintain sustainable agroecosystems.« less

  13. 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.

  14. Impacts of Climate Anomalies on the Vegetation Patterns in the Arid and Semi-Arid Zones of Uzbekistan

    NASA Astrophysics Data System (ADS)

    Dildora, Aralova; Toderich, Kristina; Dilshod, Gafurov

    2016-08-01

    Steadily rising temperature anomalies in last decades are causing changes in vegetation patterns for sensitive to climate change in arid and semi-arid dryland ecosystems. After desiccation of the Aral Sea, Uzbekistan has been left with the challenge to develop drought and heat stress monitoring system and tools (e.g., to monitor vegetation status and/crop pattern dynamics) with using remote sensing technologies in broad scale. This study examines several climate parameters, NDVI and drought indexes within geostatistical method to predict further vegetation status in arid and semi-arid zones of landscapes. This approaches aimed to extract and utilize certain variable environmental data (temperature and precipitation) for assessment and inter-linkages of vegetation cover dynamics, specifically related to predict degraded and recovered zones or desertification process in the drylands due to scarcity of water resources and high risks of climate anomalies in fragile ecosystem of Uzbekistan.

  15. Variability of the climatic oceanic frontal zones and its connection with the large-scale atmospheric forcing

    NASA Astrophysics Data System (ADS)

    Kazmin, Alexander S.

    2017-05-01

    Global satellite sea surface temperature (SST) measurements and NCEP/NCAR reanalysis wind data for the period of 1982-2009 have been used to study the seasonal and interannual variability of the main climatic oceanic frontal zones (OFZ; subpolar, subtropical and equatorial) associated with the large-scale atmospheric forcing. The seasonal variability of the OFZ is manifested in variations of their intensity (magnitude of the meridional gradient of SST) and latitudinal position of the cores (defined as areas of maximum SST gradient). The maximum intensity of the subpolar OFZ is observed in summer of the corresponding hemisphere, while subtropical OFZ are intensified synchronously in both hemispheres during boreal winter. Subtropical OFZ cores in both hemispheres shift synchronously to the south/north during the winter/summer of the Northern hemisphere, which is caused by the seasonal meridional migration of the areas of the maximum convergence of Ekman transport. All subpolar and subtropical OFZ reveal a pronounced quasi-decadal (7-10 years) variability, manifested in the variations of their intensity and latitudinal position of the zones' cores. Strengthening of the SST gradient is accompanied by a displacement of the zones' cores to the north in both hemispheres for subpolar OFZ, while subtropical OFZ cores migrate to the poles in this situation. Positive correlations between the maximum magnitude of the meridional gradient of zonally averaged SST and meridional shear of zonal wind (which is an estimate of the Ekman convergence intensity) were found for all subpolar and subtropical OFZ. Variability of the latitudinal position of subpolar OFZ cores is associated with the Ekman advection variability due to zonal wind variations (strengthening of zonal wind results in a shift of subpolar OFZ cores to the south/north in the Northern/Southern hemispheres). A period of the variability of the North Pacific equatorial OFZ is 4-5 years and is determined by the variability

  16. Vadose zone controls on damping of climate-induced transient recharge fluxes in U.S. agroecosystems

    NASA Astrophysics Data System (ADS)

    Gurdak, Jason

    2017-04-01

    Understanding the physical processes in the vadose zone that link climate variability with transient recharge fluxes has particular relevance for the sustainability of groundwater-supported irrigated agriculture and other groundwater-dependent ecosystems. Natural climate variability on interannual to multidecadal timescales has well-documented influence on precipitation, evapotranspiration, soil moisture, infiltration flux, and can augment or diminish human stresses on water resources. Here the behavior and damping depth of climate-induced transient water flux in the vadose zone is explored. The damping depth is the depth in the vadose zone that the flux variation damps to 5% of the land surface variation. Steady-state recharge occurs when the damping depth is above the water table, and transient recharge occurs when the damping depth is below the water table. Findings are presented from major agroecosystems of the United States (U.S.), including the High Plains, Central Valley, California Coastal Basin, and Mississippi Embayment aquifer systems. Singular spectrum analysis (SSA) is used to identify quasi-periodic signals in precipitation and groundwater time series that are coincident with the Arctic Oscillation (AO) (6-12 mo cycle), Pacific/North American oscillation (PNA) (<1-4 yr cycle), El Niño/Southern Oscillation (ENSO) (2-7 yr cycle), North Atlantic Oscillation (NAO) (3-6 yr cycle), Pacific Decadal Oscillation (PDO) (15-30 yr cycle), and Atlantic Multidecadal Oscillation (AMO) (50-70 yr cycle). SSA results indicate that nearly all of the quasi-periodic signals in the precipitation and groundwater levels have a statistically significant lag correlation (95% confidence interval) with the AO, PNA, ENSO, NAO, PDO, and AMO indices. Results from HYDRUS-1D simulations indicate that transient water flux through the vadose zone are controlled by highly nonlinear interactions between mean infiltration flux and infiltration period related to the modes of climate

  17. Condensation Risk of Mechanically Attached Roof Systems in Cold Climate Zones

    SciTech Connect

    Pallin, Simon B

    2013-01-01

    A white roof, cool roof, is constructed to decrease thermal loads from solar radiation, therefore saving energy by decreasing the cooling demands. Unfortunately, cool roofs with mechanically attached membrane, have shown to have a higher risk of intermediate condensation in the materials below the membrane in certain climates (Ennis & Kehrer, 2011) and in comparisons with similar construction with a darker exterior surface (Bludau, Zirkelbach, & Kuenzel, 2009). As a consequence, questions have been raised regarding the sustainability and reliability of using cool roof membranes in Northern U.S. climate zones. A white roof surface reflects more of the incident solar radiation in comparisons with a dark surface, which makes a distinguished difference on the surface temperature of the roof. However, flat roofs with either a light or dark surface and if facing a clear sky, are constantly losing energy to the sky due to the exchange of infrared radiation. This phenomenon exists both during the night and the day. During the day, if the sun shines on the roof surface, the exchange of infrared radiation typically becomes insignificant. During nights and in cold climates, the temperature difference between the roof surface and the sky can deviate up to 20 C (Hagentoft, 2001) which could result in a very cold surface temperature compared to the ambient temperature. Further, a colder surface temperature of the roof increases the energy loss and the risk of condensation in the building materials below the membrane. In conclusion, both light and dark coated roof membranes are cooled by the infrared radiation exchange during the night, though a darker membrane is more heated by the solar radiation during the day, thus decreasing the risk of condensation. The phenomenon of night time cooling from the sky and the lack of solar gains during the day is not likely the exclusive problem concerning the risk of condensation in cool roofs with mechanically attached membranes. Roof

  18. Natural climate variability modulates the expansion of oxygen minimum zone in the tropical Pacific

    NASA Astrophysics Data System (ADS)

    Ito, T.; Deutsch, C. A.

    2012-12-01

    Decrease in oceanic oxygen is predicted from ocean heat uptake and increased stratification in the warming climate. The extent of oxygen minimum zone (OMZ) in the eastern tropical Pacific is particularly sensitive to the ocean deoxygenation due to its nonlinear response to the regional oxygen inventory. Ocean time series observations show strong signature of decadal fluctuation superimposed over the long-term decreasing trend. Here, we use a combination of idealized and complex models to illustrate the physical and biogeochemical mechanisms behind the recent expansion of the tropical Pacific OMZ. Oxygen variability for the late 20th century is simulated using a three-dimensional ocean biogeochemistry model, reproducing the expansion of tropical Pacific OMZ since 1980s. Decreasing solubility and increasing apparent oxygen utilization together drive the long-term declining trend. However, these two components tend to compensate one another on interannual timescales due to their co-variation with El Nino Southern Oscillation (ENSO). Upper ocean heat content, biological oxygen utilization and upwelling of thermocline water are significantly influenced by the ENSO cycle and associated circulation changes. Furthermore, regional budget analysis reveals the important role of physical oxygen supply via equatorial zonal jets. A simple autoregressive model is constructed to illustrate the importance of decadal thermocline ventilation, integrating anomalies in physical supply and biological consumption, generating the multi-decadal variability of OMZ. Our results indicate that natural climate variability can significantly modulate the long-term ocean deoxygenation on decadal timescales through many, often competing, processes which are then reddened due to the finite memory of thermocline waters.

  19. Conservation Priorities for Prunus africana Defined with the Aid of Spatial Analysis of Genetic Data and Climatic Variables

    PubMed Central

    Vinceti, Barbara; Loo, Judy; Gaisberger, Hannes; van Zonneveld, Maarten J.; Schueler, Silvio; Konrad, Heino; Kadu, Caroline A. C.; Geburek, Thomas

    2013-01-01

    Conservation priorities for Prunus africana, a tree species found across Afromontane regions, which is of great commercial interest internationally and of local value for rural communities, were defined with the aid of spatial analyses applied to a set of georeferenced molecular marker data (chloroplast and nuclear microsatellites) from 32 populations in 9 African countries. Two approaches for the selection of priority populations for conservation were used, differing in the way they optimize representation of intra-specific diversity of P. africana across a minimum number of populations. The first method (S1) was aimed at maximizing genetic diversity of the conservation units and their distinctiveness with regard to climatic conditions, the second method (S2) at optimizing representativeness of the genetic diversity found throughout the species’ range. Populations in East African countries (especially Kenya and Tanzania) were found to be of great conservation value, as suggested by previous findings. These populations are complemented by those in Madagascar and Cameroon. The combination of the two methods for prioritization led to the identification of a set of 6 priority populations. The potential distribution of P. africana was then modeled based on a dataset of 1,500 georeferenced observations. This enabled an assessment of whether the priority populations identified are exposed to threats from agricultural expansion and climate change, and whether they are located within the boundaries of protected areas. The range of the species has been affected by past climate change and the modeled distribution of P. africana indicates that the species is likely to be negatively affected in future, with an expected decrease in distribution by 2050. Based on these insights, further research at the regional and national scale is recommended, in order to strengthen P. africana conservation efforts. PMID:23544118

  20. Adaptation and exogenous selection in a Picea glauca × Picea engelmannii hybrid zone: implications for forest management under climate change.

    PubMed

    De La Torre, Amanda R; Wang, Tongli; Jaquish, Barry; Aitken, Sally N

    2014-01-01

    The nature of selection responsible for the maintenance of the economically and ecologically important Picea glauca × Picea engelmannii hybrid zone was investigated. Genomic, phenotypic and climatic data were used to test assumptions of hybrid zone maintenance and to model future scenarios under climate change. Genome-wide estimates of admixture based on a panel of 86 candidate gene single nucleotide polymorphisms were combined with long-term quantitative data on growth and survival (over 20 yr), as well as one-time assessments of bud burst and bud set phenology, and cold hardiness traits. A total of 15,498 individuals were phenotyped for growth and survival. Our results suggest that the P. glauca × P. engelmannii hybrid zone is maintained by local adaptation to growing season length and snowpack (exogenous selection). Hybrids appeared to be fitter than pure species in intermediate environments, which fits expectations of the bounded hybrid superiority model of hybrid zone maintenance. Adaptive introgression from parental species has probably contributed to increased hybrid fitness in intermediate habitats. While P. engelmannii ancestry is higher than P. glauca ancestry in hybrid populations, on average, selective breeding in managed hybrid populations is shifting genomic composition towards P. glauca, potentially pre-adapting managed populations to warmer climates.

  1. Adaptation and exogenous selection in a Picea glauca × Picea engelmannii hybrid zone: implications for forest management under climate change

    PubMed Central

    De La Torre, Amanda R; Wang, Tongli; Jaquish, Barry; Aitken, Sally N

    2014-01-01

    The nature of selection responsible for the maintenance of the economically and ecologically important Picea glauca × Picea engelmannii hybrid zone was investigated. Genomic, phenotypic and climatic data were used to test assumptions of hybrid zone maintenance and to model future scenarios under climate change. Genome-wide estimates of admixture based on a panel of 86 candidate gene single nucleotide polymorphisms were combined with long-term quantitative data on growth and survival (over 20 yr), as well as one-time assessments of bud burst and bud set phenology, and cold hardiness traits. A total of 15 498 individuals were phenotyped for growth and survival. Our results suggest that the P. glauca × P. engelmannii hybrid zone is maintained by local adaptation to growing season length and snowpack (exogenous selection). Hybrids appeared to be fitter than pure species in intermediate environments, which fits expectations of the bounded hybrid superiority model of hybrid zone maintenance. Adaptive introgression from parental species has probably contributed to increased hybrid fitness in intermediate habitats. While P. engelmannii ancestry is higher than P. glauca ancestry in hybrid populations, on average, selective breeding in managed hybrid populations is shifting genomic composition towards P. glauca, potentially pre-adapting managed populations to warmer climates. PMID:24200028

  2. Analyzing the Implications of Climate Data on Plant Hardiness Zones for Green Infrastructure Planning: Case Study of Knoxville, Tennessee and Surrounding Region

    SciTech Connect

    Sylvester, Linda M.; Omitaomu, Olufemi A.; Parish, Esther S.

    2016-07-01

    Downscaled climate data for Knoxville, Tennessee and the surrounding region were used to investigate future changing Plant Hardiness Zones due to climate change. The methodology used is the same as the US Department of Agriculture (USDA), well-known for their creation of the standard Plant Hardiness Zone map used by gardeners and planners. USDA data were calculated from observed daily data for 1976–2005. The modeled climate data for the past is daily data from 1980-2005 and the future data is projected for 2025–2050. The average of all the modeled annual extreme minimums for each time period of interest was calculated. Each 1 km raster cell was placed into zone categories based on temperature, using the same criteria and categories of the USDA. The individual models vary between suggesting little change to the Plant Hardiness Zones to suggesting Knoxville moves into the next two Hardiness Zones. But overall, the models suggest moving into the next warmer Zone. USDA currently has the Knoxville area categorized as Zone 7a. None of the Zones calculated from the climate data models placed Knoxville in Zone 7a for the similar time period. The models placed Knoxville in a cooler Hardiness Zone and projected the area to increase to Zone 7. The modeled temperature data appears to be slightly cooler than the actual temperature data and this may explain the zone discrepancy. However, overall Knoxville is projected to increase to the next warmer Zone. As the modeled data has Knoxville, overall, moving from Zone 6 to Zone 7, it can be inferred that Knoxville, Tennessee may increase from their current Zone 7 to Zone 8.

  3. Evolution of Diurnal Asymmetry of Surface Temperature over Different Climatic Zones

    NASA Astrophysics Data System (ADS)

    Rajendran, V.; C T, D.; Chakravorty, A.; AghaKouchak, A.

    2016-12-01

    that the DTR changes are influenced by both, local and global factors working in tandem, since a warmed up ocean produces contradictory DTR trends in different climatic zones. It can be inferred from this study that the impact of a global change in a region will depend on the regional climate.

  4. Urban Heat Island Variation across a Dramatic Coastal to Desert Climate Zone: An Application to Los Angeles, CA Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Tayyebi, A.; Jenerette, D.

    2015-12-01

    Urbanization is occurring at an unprecedented rate across the globe. The resulting urban heat island (UHI), which is a well-known phenomenon in urban areas due to the increasing number and density of buildings, leads to higher temperature in urban areas than surrounding sub-urban or rural areas. Understanding the effects of landscape pattern on UHI is crucial for improving the sustainability of cities and reducing heat vulnerability. Although a variety of studies have quantified UHI, there are a lack of studies to 1) understand UHI variation at the micro-scale (e.g., neighborhood effect) for large urban areas and 2) identify variation in the sensitivity of the UHI to environmental drivers across a megacity with a pronounced climate zone (i.e. coastal to desert climates) using advanced analytical tools. In this study, we identified the interacting relationship among various environmental and socio-economic factors to better identify UHI over the Los Angeles, CA metropolitan area. We used structural equation modeling (SEM) to quantify the interacting relationships among land surface temperature (LST), land cover (NDVI), distance to ocean, elevation, and socio-economic status (neighborhood income). LST-NDVI slopes were negative across the climate zones and became progressively stronger with increasing distance from the coast. Results also showed that slopes between NDVI and neighborhood income were positive throughout the climate zone with a maximum in the relationship occurring near 25km from the coast. Because of these income-NDVI and NDVI-LST relationships we also found that slopes between LST and neighborhood income were negative throughout the climate zones and peaked at about 30km from the coast. These findings suggest assessments of urban heat vulnerability need to consider not only variation in the indicators but also variation in how the indicators influence vulnerability.

  5. Zones of Hemorrhage: Defining Vascular Injury in Military Patients with Complex Pelvic Fractures a Consensus Panel Review

    DTIC Science & Technology

    2013-03-01

    minutes until intravascular embolization or definitive surgical ligation could be performed.12 RESULTS The STReC pelvis database yielded 104 subjects with...extremity 12 54.55 10.43 Zone III 69 60 Aorta 20 28.99 17.39 Atrium/ventricle 8 11.59 6.96 Pulmonary 4 5.80 3.48 Renal 2 2.90 1.74 Vena cava 6 8.70 5.22...mortality rate. Significant predictors of mortality in unstable fractures include large-vessel injury, anatomic brain injury, cardio- pulmonary injury

  6. Climate change impacts on rural poverty in low-elevation coastal zones

    NASA Astrophysics Data System (ADS)

    Barbier, Edward B.

    2015-11-01

    This paper identifies the low-elevation coastal zone (LECZ) populations and developing regions most vulnerable to sea-level rise and other coastal hazards, such as storm surges, coastal erosion and salt-water intrusion. The focus is on the rural poor in the LECZ, as their economic livelihoods are especially endangered both directly by coastal hazards and indirectly through the impacts of climate change on key coastal and near-shore ecosystems. Using geo-spatially referenced malnutrition and infant mortality data for 2000 as a proxy for poverty, this study finds that just 15 developing countries contain over 90% of the world's LECZ rural poor. Low-income countries as a group have the highest incidence of poverty, which declines somewhat for lower middle-income countries, and then is much lower for upper middle-income economies. South Asia, East Asia and the Pacific and Sub-Saharan Africa account for most of the world's LECZ rural poor, and have a high incidence of poverty among their rural LECZ populations. Although fostering growth, especially in coastal areas, may reduce rural poverty in the LECZ, additional policy actions will be required to protect vulnerable communities from disasters, to conserve and restore key coastal and near-shore ecosystems, and to promote key infrastructure investments and coastal community response capability.

  7. Assessment of wind and wave climate in the Shenzhen coastal zone of the South China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Xinping; Wang, Kaimin; Zhang, Zenghai; Zeng, Yindong; O'Driscoll, Kieran

    2017-04-01

    Wind and wave climate in the Shenzhen coastal zone adjacent to Hong Kong in the south China Sea have been studied by means of observational data from six buoys. These are the first available measurements of wind and wave parameters from buoys for the period 2014-2016 covering the area of the study, including Dapeng Bay and Daya Bay, and the area between them, as well as Shenzhen Bay. Water depths at buoy locations are very shallow, ranging from 3 to 22 m. Results show that annual mean wind speed in the region varied between 3.1 and 4.1 m/s, leading to mean wind power values of between 37 and 94 Wm-2. Significant wave heights and wave powers at the buoy locations were very small over the period 2014-2016, with annual mean values ranging between 0.1 and 0.6 m, and 0.03 and 1.25 Wm-1, respectively. Monthly and seasonal variability of wave heights and wave powers differ between buoys, as do wind and wave directions, which do not match with typical monsoon characteristics in the South China Sea.

  8. Building America Case Study: Rehabilitation of USDA Multifamily Homes, Georgia (Climate Zones 2-4)

    SciTech Connect

    2016-04-01

    Rea Ventures Group, LLC, (Rea Ventures) partnered with Southface Energy Institute (Southface) on the rehabilitation of 418 low-income rental multifamily apartments located at 14 different properties in Georgia (Climate Zones 2-4). These 22-year old, individually-metered units were arranged in rowhouse or townhouse style units. Rehabilitation plans were developed using a process prescribed by the US Department of Agriculture (USDA) Rural Development program, who partially funded the building upgrades. The USDA is responsible for building, upgrading, and subsidizing housing in rural areas nationwide. In 2012, over $100 million was allocated in grants and loans. Due to the unique financing mechanism as well as long-term ownership requirements, property owners are especially motivated to invest in upgrades that will increase durability and tenant retention. These buildings represent a large stock of rural affordable housing that have the potential for significant energy and cost savings for property owners and tenants. Southface analyzed the energy upgrade potential of one stereotypical property in the Rea Ventures portfolio. This study will provide insight into the most cost-effective, implementable energy efficiency and durability upgrades for this age multifamily housing, having an enormous impact not only on the portfolio of Rea Ventures but on the vast USDA and larger Federal portfolio. Additionally, Southface will identify gaps in the current capital needs assessment process, examine available audit and simulation tools and protocols, and evaluate additional auditor training or certification needs.

  9. Climate change impacts on rural poverty in low-elevation coastal zones

    NASA Astrophysics Data System (ADS)

    Barbier, Edward B.

    2015-11-01

    This paper identifies the low-elevation coastal zone (LECZ) populations and developing regions most vulnerable to sea-level rise and other coastal hazards, such as storm surges, coastal erosion and salt-water intrusion. The focus is on the rural poor in the LECZ, as their economic livelihoods are especially endangered both directly by coastal hazards and indirectly through the impacts of climate change on key coastal and near-shore ecosystems. Using geo-spatially referenced malnutrition and infant mortality data for 2000 as a proxy for poverty, this study finds that just 15 developing countries contain over 90% of the world's LECZ rural poor. Low-income countries as a group have the highest incidence of poverty, which declines somewhat for lower middle-income countries, and then is much lower for upper middle-income economies. South Asia, East Asia and the Pacific and Sub-Saharan Africa account for most of the world's LECZ rural poor, and have a high incidence of poverty among their rural LECZ populations. Although fostering growth, especially in coastal areas, may reduce rural poverty in the LECZ, additional policy actions will be required to protect vulnerable communities from disasters, to conserve and restore key coastal and near-shore ecosystems, and to promote key infrastructure investments and coastal community response capability.

  10. Integration and Typologies of Vulnerability to Climate Change: A Case Study from Australian Wheat Sheep Zones

    PubMed Central

    Huai, Jianjun

    2016-01-01

    Although the integrated indicator methods have become popular for assessing vulnerability to climate change, their proliferation has introduced a confusing array of scales and indicators that cause a science-policy gap. I argue for a clear adaptation pathway in an “integrative typology” of regional vulnerability that matches appropriate scales, optimal measurements and adaptive strategies in a six-dimensional and multi-level analysis framework of integration and typology inspired by the “5W1H” questions: “Who is concerned about how to adapt to the vulnerability of what to what in some place (where) at some time (when)?” Using the case of the vulnerability of wheat, barley and oats to drought in Australian wheat sheep zones during 1978–1999, I answer the “5W1H” questions through establishing the “six typologies” framework. I then optimize the measurement of vulnerability through contrasting twelve kinds of vulnerability scores with the divergence of crops yields from their regional mean. Through identifying the socioeconomic constraints, I propose seven generic types of crop-drought vulnerability and local adaptive strategy. Our results illustrate that the process of assessing vulnerability and selecting adaptations can be enhanced using a combination of integration, optimization and typology, which emphasize dynamic transitions and transformations between integration and typology. PMID:27670975

  11. Integration and Typologies of Vulnerability to Climate Change: A Case Study from Australian Wheat Sheep Zones.

    PubMed

    Huai, Jianjun

    2016-09-27

    Although the integrated indicator methods have become popular for assessing vulnerability to climate change, their proliferation has introduced a confusing array of scales and indicators that cause a science-policy gap. I argue for a clear adaptation pathway in an "integrative typology" of regional vulnerability that matches appropriate scales, optimal measurements and adaptive strategies in a six-dimensional and multi-level analysis framework of integration and typology inspired by the "5W1H" questions: "Who is concerned about how to adapt to the vulnerability of what to what in some place (where) at some time (when)?" Using the case of the vulnerability of wheat, barley and oats to drought in Australian wheat sheep zones during 1978-1999, I answer the "5W1H" questions through establishing the "six typologies" framework. I then optimize the measurement of vulnerability through contrasting twelve kinds of vulnerability scores with the divergence of crops yields from their regional mean. Through identifying the socioeconomic constraints, I propose seven generic types of crop-drought vulnerability and local adaptive strategy. Our results illustrate that the process of assessing vulnerability and selecting adaptations can be enhanced using a combination of integration, optimization and typology, which emphasize dynamic transitions and transformations between integration and typology.

  12. Integration and Typologies of Vulnerability to Climate Change: A Case Study from Australian Wheat Sheep Zones

    NASA Astrophysics Data System (ADS)

    Huai, Jianjun

    2016-09-01

    Although the integrated indicator methods have become popular for assessing vulnerability to climate change, their proliferation has introduced a confusing array of scales and indicators that cause a science-policy gap. I argue for a clear adaptation pathway in an “integrative typology” of regional vulnerability that matches appropriate scales, optimal measurements and adaptive strategies in a six-dimensional and multi-level analysis framework of integration and typology inspired by the “5W1H” questions: “Who is concerned about how to adapt to the vulnerability of what to what in some place (where) at some time (when)?” Using the case of the vulnerability of wheat, barley and oats to drought in Australian wheat sheep zones during 1978–1999, I answer the “5W1H” questions through establishing the “six typologies” framework. I then optimize the measurement of vulnerability through contrasting twelve kinds of vulnerability scores with the divergence of crops yields from their regional mean. Through identifying the socioeconomic constraints, I propose seven generic types of crop-drought vulnerability and local adaptive strategy. Our results illustrate that the process of assessing vulnerability and selecting adaptations can be enhanced using a combination of integration, optimization and typology, which emphasize dynamic transitions and transformations between integration and typology.

  13. On the use of mean groundwater age, life expectancy and capture probability for defining aquifer vulnerability and time-of-travel zones for source water protection.

    PubMed

    Molson, J W; Frind, E O

    2012-01-01

    Protection and sustainability of water supply wells requires the assessment of vulnerability to contamination and the delineation of well capture zones. Capture zones, or more generally, time-of-travel zones corresponding to specific contaminant travel times, are most commonly delineated using advective particle tracking. More recently, the capture probability approach has been used in which a probability of capture of P=1 is assigned to the well and the growth of a probability-of-capture plume is tracked backward in time using an advective-dispersive transport model. This approach accounts for uncertainty due to local-scale heterogeneities through the use of macrodispersion. In this paper, we develop an alternative approach to capture zone delineation by applying the concept of mean life expectancy E (time remaining before being captured by the well), and we show how life expectancy E is related to capture probability P. Either approach can be used to delineate time-of-travel zones corresponding to specific travel times, as well as the ultimate capture zone. The related concept of mean groundwater age A (time since recharge) can also be applied in the context of defining the vulnerability of a pumped aquifer. In the same way as capture probability, mean life expectancy and groundwater age account for local-scale uncertainty or unresolved heterogeneities through macrodispersion, which standard particle tracking neglects. The approach is tested on 2D and 3D idealized systems, as well as on several watershed-scale well fields within the Regional Municipality of Waterloo, Ontario, Canada. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Red Shell: Defining a High-Risk Zone of Normal Tissue Damage in Stereotactic Body Radiation Therapy

    SciTech Connect

    Yang, Jun; Fowler, Jack F.; Lamond, John P.; Lanciano, Rachelle; Feng Jing; Brady, Luther W.

    2010-07-01

    Purpose: To define a volume of tissue just outside of the clinical target volume (CTV) or planning target volume (PTV) in stereotactic body radiation therapy (SBRT) that receives doses appreciably above the tolerance level and in which other critical tissue structures must be avoided. Methods and Materials: We define the tissue between the borders of the CTV and PTV as the Inner Red Shell. The tissue surrounding the PTV that receives higher than the local tissue tolerance is defined as the Outer Red Shell. Contributing factors to the volume of the Red Shell include the prescription dose, dose gradient and PTV size, together with the type of tissue and its tolerance are discussed. An illustrative example and two clinical cases are reported. Results: The volume of Red Shell increases with higher prescription dose, slower dose fall-off, larger PTV volume, and higher tissue radiosensitivity. Avoidance of proximal critical serial organs may alter the volume and shape of the Red Shell after repeated, detailed treatment planning. Conclusion: Rather than defining tolerance and toxicity as simply a dose level received by the tissues, the volume of tissue receiving risk levels above tolerance can be quantified as the 'cost' of SBRT. This concept may be adopted in other techniques offering ablative and high-dose gradients. Further consideration should be given to collecting clinical data for refining the choice of constraint doses, especially in parts of the brain, lung, liver, and kidney.

  15. Changes in the world rivers' discharge projected from an updated high resolution dataset of current and future climate zones

    NASA Astrophysics Data System (ADS)

    Santini, Monia; di Paola, Arianna

    2015-12-01

    In this paper, an updated global map of the current climate zoning and of its projections, according to the Köppen-Geiger classification, is first provided. The map at high horizontal resolution (0.5° × 0.5°), representative of the current (i.e. 1961-2005) conditions, is based on the Climate Research Unit dataset holding gridded series of historical observed temperature and precipitation, while projected conditions rely on the simulated series, for the same variables, by the General Circulation Model CMCC-CM. Modeled variables were corrected for their bias and then projections of climate zoning were generated for the medium term (2006-2050) and long term (2056-2100) future periods, under RCP 4.5 and RCP 8.5 emission scenarios. Results show that Equatorial and Arid climates will spread at the expenses of Snow and Polar climates, with the Warm Temperate experiencing more moderate increase. Maps of climate zones are valuable for a wide range of studies on climate change and its impacts, especially those regarding the water cycle that is strongly regulated by the combined conditions of precipitation and temperature. As example of large scale hydrological applications, in this work we tested and implemented a spatial statistical procedure, the geographically weighted regression among climate zones' surface and mean annual discharge (MAD) at hydrographic basin level, to quantify likely changes in MAD for the main world rivers monitored through the Global Runoff Data Center database. The selected river basins are representative of more than half of both global superficial freshwater resources and world's land area. Globally, a decrease in MAD is projected both in the medium term and long term, while spatial differences highlight how some areas require efforts to avoid consequences of amplified water scarcity, while other areas call for strategies to take the opportunity from the expected increase in water availability. Also the fluctuations of trends between the

  16. A restricted period for formation of outer subventricular zone defined by Cdh1 and Trnp1 levels.

    PubMed

    Martínez-Martínez, Maria Ángeles; De Juan Romero, Camino; Fernández, Virginia; Cárdenas, Adrián; Götz, Magdalena; Borrell, Víctor

    2016-06-06

    The outer subventricular zone (OSVZ) is a germinal layer playing key roles in the development of the neocortex, with particular relevance in gyrencephalic species such as human and ferret, where it contains abundant basal radial glia cells (bRGCs) that promote cortical expansion. Here we identify a brief period in ferret embryonic development when apical RGCs generate a burst of bRGCs that become founders of the OSVZ. After this period, bRGCs in the OSVZ proliferate and self-renew exclusively locally, thereby forming a self-sustained lineage independent from the other germinal layers. The time window for the brief period of OSVZ bRGC production is delineated by the coincident downregulation of Cdh1 and Trnp1, and their upregulation reduces bRGC production and prevents OSVZ seeding. This mechanism in cortical development may have key relevance in brain evolution and disease.

  17. A restricted period for formation of outer subventricular zone defined by Cdh1 and Trnp1 levels

    PubMed Central

    Martínez-Martínez, Maria Ángeles; De Juan Romero, Camino; Fernández, Virginia; Cárdenas, Adrián; Götz, Magdalena; Borrell, Víctor

    2016-01-01

    The outer subventricular zone (OSVZ) is a germinal layer playing key roles in the development of the neocortex, with particular relevance in gyrencephalic species such as human and ferret, where it contains abundant basal radial glia cells (bRGCs) that promote cortical expansion. Here we identify a brief period in ferret embryonic development when apical RGCs generate a burst of bRGCs that become founders of the OSVZ. After this period, bRGCs in the OSVZ proliferate and self-renew exclusively locally, thereby forming a self-sustained lineage independent from the other germinal layers. The time window for the brief period of OSVZ bRGC production is delineated by the coincident downregulation of Cdh1 and Trnp1, and their upregulation reduces bRGC production and prevents OSVZ seeding. This mechanism in cortical development may have key relevance in brain evolution and disease. PMID:27264089

  18. Characterization of flow and transport processes within the unsaturated zone of Yucca Mountain, Nevada, under current and future climates.

    PubMed

    Wu, Yu-Shu; Pan, Lehua; Zhang, W; Bodvarsson, G S

    2002-02-01

    This paper presents a large-scale modeling study characterizing fluid flow and tracer transport in the unsaturated zone of Yucca Mountain, Nevada, a potential repository site for storing high-level radioactive waste. The study has been conducted using a three-dimensional numerical model, which incorporates a wide variety of field data and takes into account the coupled processes of flow and transport in the highly heterogeneous, unsaturated fractured porous rock. The modeling approach is based on a dual-continuum formulation of coupled multiphase fluid and tracer transport through fractured porous rock. Various scenarios of current and future climate conditions and their effects on the unsaturated zone are evaluated to aid in the assessment of the proposed repository's system performance using different conceptual models. These models are calibrated against field-measured data. Model-predicted flow and transport processes under current and future climates are discussed.

  19. Evaluation of ERA-Interim for tropospheric delay and water vapour estimation in different climate zones using ground-based GNSS observations

    NASA Astrophysics Data System (ADS)

    Ahmed, Furqan; Hunegnaw, Addisu; Teferle, Norman; Bingley, Richard

    2017-04-01

    Tropospheric delay and integrated water vapour (IWV) derived from climate reanalysis models, such as that of the European Centre for Medium-range Weather Forecasts (ECMWF) namely the ECMWF ReAnalysis-Interim (ERA-Interim), are widely used in many geodetic and atmospheric applications. Therefore, it is of interest to assess the quality of these reanalysis products using available observations. Observations from Global Navigation Satellite Systems (GNSS) are, as of now, available for a period of over 2 decades and their global availability make it possible to validate the zenith total delay (ZTD) and IWV obtained from climate reanalysis models in different geographical and climatic regions. In this study, a 5-year long homogeneously reprocessed GNSS data set based on double differenced positioning strategy and containing over 400 globally distributed ground-based GNSS stations has been used as a reference to validate the ZTD estimates obtained from the ERA-Interim climate reanalysis model in 25 different climate zones. It has been studied how the difference between the ERA-Interim ZTD and the GNSS-derived ZTD varies with respect to the different climate zones as well as the topographic variations in a particular climate zone. Periodicity in the ZTD residuals in different climate zones has been analyzed. Furthermore, the variation of the ZTD differences with respect to latitude has been presented. Finally, for one GNSS station in each of the 25 climate zones, IWV derived from ERA-Interim has been compared to the IWV derived using GNSS observations.

  20. Northward expansion and rainfall seasonality amplification of the mediterranean climate zones projected in 21st century scenario

    NASA Astrophysics Data System (ADS)

    Alessandri, Andrea; Cherchi, Annalisa; De Felice, Matteo; Mariotti, Annarita; Pan, Yutong; Zeng, Ning

    2013-04-01

    The Mediterranean climate is a major climate type of the Köppen classification that is characterized by hot, dry summers and cool, wet winters and located between about 30° and 45° latitude on the western sides of the continents (Koppen, 1900; Lionello 2012). By applying the latest development of the Koppen-Geiger classification scheme, we assessed the projected change of Mediterranean climate areas in the 21st century under the RCP4.5 stabilization scenario. The capability of the CMIP5 models in reproducing realistic Mediterranean climate regions is firstly assessed globally for the historical period (1980-2005). The projected multi-model change in the 21st century with respect to the historical period is then evaluated with particular focus on the Euro-Mediterranean region. In the northern hemisphere over both the Euro-Mediterranean and the Western-US regions, the Mediterranean climate zones expand considerably during the 21st century. In particular, over Europe, the expansion is accompanied by a northward shift of the Mediterranean climate in countries like UK, France, even Scandinavia, while its southern margins being replaced by the arid climate types. This behavior characterizes some part of southern Italy, southern Greece and Middle East, where the annual mean precipitation decreases below the threshold that characterizes arid climates. In the Euro-Mediterranean sector, the poleward expansion of the Mediterranean-type climate zone is related to the amplification of the rainfall seasonal cycle. In fact, the difference between winter and summer precipitation increases to fulfill the Mediterranean climate seasonality in more regions towards the north. By applying a vertically-integrated moisture budget analysis we show that the amplification of rainfall seasonality is primarily related to the "direct moisture effect" (i.e. the increase of moisture transport by assuming no change in atmospheric circulation), thus consistent with a "poor-get-poorer" mechanism

  1. Using borehole geophysics and cross-borehole flow testing to define hydraulic connections between fracture zones in bedrock aquifers

    USGS Publications Warehouse

    Paillet, Frederick L.

    1993-01-01

    Nearly a decade of intensive geophysical logging at fractured rock hydrology research sites indicates that geophysical logs can be used to identify and characterize fractures intersecting boreholes. However, borehole-to-borehole flow tests indicate that only a few of the apparently open fractures found to intersect boreholes conduct flow under test conditions. This paper presents a systematic approach to fracture characterization designed to define the distribution of fractures along boreholes, relate the measured fracture distribution to structure and lithology of the rock mass, and define the nature of fracture flow paths across borehole arrays. Conventional electrical resistivity, gamma, and caliper logs are used to define lithology and large-scale structure. Borehole wall image logs obtained with the borehole televiewer are used to give the depth, orientation, and relative size of fractures in situ. High-resolution flowmeter measurements are used to identify fractures conducting flow in the rock mass adjacent to the boreholes. Changes in the flow field over time are used to characterize the hydraulic properties of fracture intersections between boreholes. Application of this approach to an array of 13 boreholes at the Mirror Lake, New Hamsphire site demonstrates that the transient flow analysis can be used to distinguish between fractures communicating with each other between observation boreholes, and those that are hydraulically isolated from each other in the surrounding rock mass. The Mirror Lake results also demonstrate that the method is sensitive to the effects of boreholes on the hydraulic properties of the fractured-rock aquifer. Experiments conducted before and after the drilling of additional boreholes in the array and before and after installation of packers in existing boreholes demonstrate that the presence of new boreholes or the inflation of packers in existing boreholes has a large effect on the measured hydraulic properties of the rock mass

  2. Towards Consistent Mapping of Urban Structures - Global Human Settlement Layer and Local Climate Zones

    NASA Astrophysics Data System (ADS)

    Bechtel, B.; Pesaresi, M.; See, L.; Mills, G.; Ching, J.; Alexander, P. J.; Feddema, J. J.; Florczyk, A. J.; Stewart, I.

    2016-06-01

    Although more than half of the Earth's population live in urban areas, we know remarkably little about most cities and what we do know is incomplete (lack of coverage) and inconsistent (varying definitions and scale). While there have been considerable advances in the derivation of a global urban mask using satellite information, the complexity of urban structures, the heterogeneity of materials, and the multiplicity of spectral properties have impeded the derivation of universal urban structural types (UST). Further, the variety of UST typologies severely limits the comparability of such studies and although a common and generic description of urban structures is an essential requirement for the universal mapping of urban structures, such a standard scheme is still lacking. More recently, there have been two developments in urban mapping that have the potential for providing a standard approach: the Local Climate Zone (LCZ) scheme (used by the World Urban Database and Access Portal Tools project) and the Global Human Settlement Layer (GHSL) methodology by JRC. In this paper the LCZ scheme and the GHSL LABEL product were compared for selected cities. The comparison between both datasets revealed a good agreement at city and coarse scale, while the contingency at pixel scale was limited due to the mismatch in grid resolution and typology. At a 1 km scale, built-up as well as open and compact classes showed very good agreement in terms of correlation coefficient and mean absolute distance, spatial pattern, and radial distribution as a function of distance from town, which indicates that a decomposition relevant for modelling applications could be derived from both. On the other hand, specific problems were found for both datasets, which are discussed along with their general advantages and disadvantages as a standard for UST classification in urban remote sensing.

  3. Evaluation of the thermal behaviour of different 'local climate zones' in Belgium

    NASA Astrophysics Data System (ADS)

    Verdonck, Marie-Leen; Demuzere, Matthias; Hooyberghs, Hans; Van Coillie, Frieke

    2016-04-01

    Urban areas are one of the most important human habitats; already 50% of the world's population is living there and this percentage is expected to rise to 70% by 2050. Global warming and the increasing world population will only put more pressure on the living conditions in these habitats. From a thermal comfort point of view it is clear that there is a need for sustainable urban planning that integrates the thermal behaviour of these new developments. To develop sustainable urban planning it is key to know what the influence of a new development will be on the thermal behaviour of the city. Classifying the city according to the local climate zone (LCZ) scheme can provide insights in the thermal behaviour of a city. The WUDAPT LCZ classification framework makes it possible to do so in a spatially explicit manner. This study presents an evaluation of the thermal behaviour of LCZ in three different Belgian cities (Brussels, Antwerp, Ghent) based on modelled air and surface temperature. First LCZ maps were delineated for the three cities. The maps were built based on Landsat and high resolution LiDAR images conform to the WUDAPT LCZ classification framework. Meter- resolution LiDAR images provide useful information on building height and were used to improve the LCZ maps. An accuracy assessment stage was added to confirm the validity of the maps. Secondly, the LCZ maps were used as input data for the URBCLIM model to model air and surface temperature. With the modelling results we characterized the thermal behaviour of every LCZ. In a next step the results for the different cities are compared and the generic character of the WUDAPT LCZ classification framework is evaluated. The main incentive for this study is to investigate whether LCZ maps can be used to foresee the influence of future urban growth scenario's on the thermal comfort in cities in Belgium.

  4. Disaggregating Tropical Disease Prevalence by Climatic and Vegetative Zones within Tropical West Africa

    PubMed Central

    Beckley, Carl S.; Shaban, Salisu; Palmer, Guy H.; Hudak, Andrew T.; Noh, Susan M.; Futse, James E.

    2016-01-01

    Tropical infectious disease prevalence is dependent on many socio-cultural determinants. However, rainfall and temperature frequently underlie overall prevalence, particularly for vector-borne diseases. As a result these diseases have increased prevalence in tropical as compared to temperate regions. Specific to tropical Africa, the tendency to incorrectly infer that tropical diseases are uniformly prevalent has been partially overcome with solid epidemiologic data. This finer resolution data is important in multiple contexts, including understanding risk, predictive value in disease diagnosis, and population immunity. We hypothesized that within the context of a tropical climate, vector-borne pathogen prevalence would significantly differ according to zonal differences in rainfall, temperature, relative humidity and vegetation condition. We then determined if these environmental data were predictive of pathogen prevalence. First we determined the prevalence of three major pathogens of cattle, Anaplasma marginale, Babesia bigemina and Theileria spp, in the three vegetation zones where cattle are predominantly raised in Ghana: Guinea savannah, semi-deciduous forest, and coastal savannah. The prevalence of A. marginale was 63%, 26% for Theileria spp and 2% for B. bigemina. A. marginale and Theileria spp. were significantly more prevalent in the coastal savannah as compared to either the Guinea savanna or the semi-deciduous forest, supporting acceptance of the first hypothesis. To test the predictive power of environmental variables, the data over a three year period were considered in best subsets multiple linear regression models predicting prevalence of each pathogen. Corrected Akaike Information Criteria (AICc) were assigned to the alternative models to compare their utility. Competitive models for each response were averaged using AICc weights. Rainfall was most predictive of pathogen prevalence, and EVI also contributed to A. marginale and B. bigemina prevalence

  5. Disaggregating Tropical Disease Prevalence by Climatic and Vegetative Zones within Tropical West Africa.

    PubMed

    Beckley, Carl S; Shaban, Salisu; Palmer, Guy H; Hudak, Andrew T; Noh, Susan M; Futse, James E

    2016-01-01

    Tropical infectious disease prevalence is dependent on many socio-cultural determinants. However, rainfall and temperature frequently underlie overall prevalence, particularly for vector-borne diseases. As a result these diseases have increased prevalence in tropical as compared to temperate regions. Specific to tropical Africa, the tendency to incorrectly infer that tropical diseases are uniformly prevalent has been partially overcome with solid epidemiologic data. This finer resolution data is important in multiple contexts, including understanding risk, predictive value in disease diagnosis, and population immunity. We hypothesized that within the context of a tropical climate, vector-borne pathogen prevalence would significantly differ according to zonal differences in rainfall, temperature, relative humidity and vegetation condition. We then determined if these environmental data were predictive of pathogen prevalence. First we determined the prevalence of three major pathogens of cattle, Anaplasma marginale, Babesia bigemina and Theileria spp, in the three vegetation zones where cattle are predominantly raised in Ghana: Guinea savannah, semi-deciduous forest, and coastal savannah. The prevalence of A. marginale was 63%, 26% for Theileria spp and 2% for B. bigemina. A. marginale and Theileria spp. were significantly more prevalent in the coastal savannah as compared to either the Guinea savanna or the semi-deciduous forest, supporting acceptance of the first hypothesis. To test the predictive power of environmental variables, the data over a three year period were considered in best subsets multiple linear regression models predicting prevalence of each pathogen. Corrected Akaike Information Criteria (AICc) were assigned to the alternative models to compare their utility. Competitive models for each response were averaged using AICc weights. Rainfall was most predictive of pathogen prevalence, and EVI also contributed to A. marginale and B. bigemina prevalence

  6. Prediction of Root Zone Soil Moisture using Remote Sensing Products and In-Situ Observation under Climate Change Scenario

    NASA Astrophysics Data System (ADS)

    Singh, G.; Panda, R. K.; Mohanty, B.

    2015-12-01

    Prediction of root zone soil moisture status at field level is vital for developing efficient agricultural water management schemes. In this study, root zone soil moisture was estimated across the Rana watershed in Eastern India, by assimilation of near-surface soil moisture estimate from SMOS satellite into a physically-based Soil-Water-Atmosphere-Plant (SWAP) model. An ensemble Kalman filter (EnKF) technique coupled with SWAP model was used for assimilating the satellite soil moisture observation at different spatial scales. The universal triangle concept and artificial intelligence techniques were applied to disaggregate the SMOS satellite monitored near-surface soil moisture at a 40 km resolution to finer scale (1 km resolution), using higher spatial resolution of MODIS derived vegetation indices (NDVI) and land surface temperature (Ts). The disaggregated surface soil moisture were compared to ground-based measurements in diverse landscape using portable impedance probe and gravimetric samples. Simulated root zone soil moisture were compared with continuous soil moisture profile measurements at three monitoring stations. In addition, the impact of projected climate change on root zone soil moisture were also evaluated. The climate change projections of rainfall were analyzed for the Rana watershed from statistically downscaled Global Circulation Models (GCMs). The long-term root zone soil moisture dynamics were estimated by including a rainfall generator of likely scenarios. The predicted long term root zone soil moisture status at finer scale can help in developing efficient agricultural water management schemes to increase crop production, which lead to enhance the water use efficiency.

  7. The Importance of Simulating Unsaturated Zone Flow in the Humid Climate of the Trout Lake Basin, Northern Wisconsin

    NASA Astrophysics Data System (ADS)

    Hunt, R. J.; Prudic, D. E.; Walker, J. F.; Anderson, M. P.

    2006-12-01

    standard RCH approach, but the timing was less representative of field conditions. In addition, accounting for unsaturated zone flow provided a more representative simulation of the watershed-scale groundwater system, both in a better fit to transient head data as well as stream flows and lake stages. These results demonstrate that even transient flow models in humid climates with relatively shallow water tables may benefit from a more realistic representation of unsaturated zone flow. Niswonger, R.G., D.E. Prudic, and R.S. Regan, 2006, Documentation of the Unsaturated-Zone Flow (UZF1) Package for Modeling Unsaturated Flow Between the Land Surface and the Water Table with MODFLOW- 2005. Techniques and Methods 6-A19, Chapter 19 of Section A, Ground Water, of Book 6, Modeling Techniques, 62 p.

  8. Residue dynamics of fenamidone and mancozeb on gherkin under two agro climatic zones in the state of Karnataka, India.

    PubMed

    Mohapatra, Soudamini; Deepa, M

    2012-04-01

    Residue dynamics of fenamidone and mancozeb on gherkin was evaluated at two different agro climatic zones i.e. at Bangalore (Zone-1) and Dharwad (Zone-2) in the state of Karnataka, India. Two treatments of the combination formulation (fenamidone 10% + mancozeb 50%) were given at the standard dose 150 + 750 g a.i. ha(-1) and double dose 300 + 1,500 g a.i. ha(-1). Initial residue deposits of fenamidone were 0.467 and 0.474 mg kg(-1) at Zone-1 and 2, respectively from standard dose treatment. From double dose treatment they were 0.964 and 0.856 mg kg(-1), respectively. Fenamidone residues persisted for 15 and 10 days and dissipated with the half-life of 4 and 3 days at Zone-1 and 2, respectively. Mancozeb residue deposits on gherkin were 0.383 and 0.428 mg kg(-1) from standard dose and 0.727 and 0.626 mg kg(-1) from double dose treatment at Zone-1 and 2, respectively. Mancozeb residues dissipated with the half-life of 2 and 1 day, respectively. Residues of both fenamidone and mancozeb dissipated faster at Zone-2 compared to Zone-1. The limit of quantification of fenamidone and mancozeb were 0.02 and 0.1 mg kg(-1), respectively in both gherkin and soil. Residues of fenamidone and mancozeb in soil collected on the 20th day from the 2 locations were found to be below quantifiable limit of both fungicides.

  9. Rapid turnover of dissolved DMS and DMSP by defined bacterioplankton communities in the stratified euphotic zone of the North Sea

    NASA Astrophysics Data System (ADS)

    Zubkov, Mikhail V.; Fuchs, Bernhard M.; Archer, Stephen D.; Kiene, Ronald P.; Amann, Rudolf; Burkill, Peter H.

    Bacterioplankton-driven turnover of the algal osmolyte, dimethylsulphoniopropionate (DMSP), and its degradation product, dimethylsulphide (DMS) the major natural source of atmospheric sulphur, were studied during a Lagrangian SF 6-tracer experiment in the North Sea (60°N, 3°E). The water mass sampled within the euphotic zone was characterised by a surface mixed layer (from 0 m to 13-30 m) and a subsurface layer (from 13-30 m to 45-58 m) separated by a 2°C thermocline spanning 2 m. The fluxes of dissolved DMSP (DMSPd) and DMS were determined using radioactive tracer techniques. Rates of the simultaneous incorporation of 14C-leucine and 3H-thymidine were measured to estimate bacterioplankton production. Flow cytometry was employed to discriminate subpopulations and to determine the numbers and biomass of bacterioplankton by staining for nucleic acids and proteins. Bacterioplankton subpopulations were separated by flow cytometric sorting and their composition determined using 16S ribosomal gene cloning/sequencing and fluorescence in situ hybridisation with designed group-specific oligonucleotide probes. A subpopulation, dominated by bacteria related to Roseobacter-( α-proteobacteria), constituted 26-33% of total bacterioplankton numbers and 45-48% of biomass in both surface and subsurface layers. The other abundant prokaryotes were a group within the SAR86 cluster of γ-proteobacteria and bacteria from the Cytophaga-Flavobacterium—cluster. Bacterial consumption of DMSPd was greater in the subsurface layer (41 nM d -1) than in the surface layer (20 nM d -1). Bacterioplankton tightly controlled the DMSPd pool, particularly in the subsurface layer, with a turnover time of 2 h, whereas the turnover time of DMSPd in the surface layer was 10 h. Consumed DMSP satisfied the majority of sulphur demands of bacterioplankton, even though bacterioplankton assimilated only about 2.5% and 6.0% of consumed DMSPd sulphur in the surface and subsurface layers, respectively

  10. Diverse effects of crop distribution and climate change on crop production in the agro-pastoral transitional zone of China

    NASA Astrophysics Data System (ADS)

    Qiao, Jianmin; Yu, Deyong; Wang, Qianfeng; Liu, Yupeng

    2017-07-01

    Both crop distribution and climate change are important drivers for crop production and can affect food security, which is an important requirement for sustainable development. However, their effects on crop production are confounded and warrant detailed investigation. As a key area for food production that is sensitive to climate change, the agro-pastoral transitional zone (APTZ) plays a significant role in regional food security. To investigate the respective effects of crop distribution and climate change on crop production, the well-established GIS-based Environmental Policy Integrated Climate (EPIC) model was adopted with different scenario designs in this study. From 1980 to 2010, the crop distribution for wheat, maize, and rice witnessed a dramatic change due to agricultural policy adjustments and ecological engineering-related construction in the APTZ. At the same time, notable climate change was observed. The simulation results indicated that the climate change had a positive impact on the crop production of wheat, maize, and rice, while the crop distribution change led to an increase in the production of maize and rice, but a decrease in the wheat production. Comparatively, crop distribution change had a larger impact on wheat (-1.71 × 106 t) and maize (8.53 × 106 t) production, whereas climate change exerted a greater effect on rice production (0.58 × 106 t), during the period from 1980 to 2010 in the APTZ. This study is helpful to understand the mechanism of the effects of crop distribution and climate change on crop production, and aid policy makers in reducing the threat of future food insecurity.

  11. Is it necessary to define the ictal onset zone with EEG prior to performing resective epilepsy surgery?

    PubMed

    Miller, John W; Cole, Andrew J

    2011-02-01

    When evaluating candidates for neurosurgical treatment for medically intractable epilepsy, is it always necessary to define the region of seizure onset with EEG? A simple answer to this question is not possible. There are specific situations where surgery is commonly performed without clear EEG ictal localization, and other situations where electrical localization is mandatory. However, opinions differ in many other situations. What are the core issues for determining when EEG localization is necessary? Neuroimaging is imperfect. It does not always accurately identify the site of seizure origination, because seizures do not always arise from visible structural lesions. EEG localization is also imperfect, as well as expensive and time consuming. Sometimes the site of origin is not identified, or a region of spread is misidentified as site of origin. False localization and lateralization can occur. Finally, epilepsy surgery is imperfect. It can produce life-changing results, but it carries risk, and surgical failure is not rare. The limitations of these methods, and the high stakes of epilepsy surgery imply that we should be very cautious to omit EEG studies. The desire to improve access to epilepsy surgery, and to minimize the expense and risk from inpatient EEG studies, must be weighed against the possibility of an ineffective resection. To improve outcomes, improvements in both neuroimaging and EEG techniques are needed.

  12. The climate of the coast and fog zone in the Tarapacá Region, Atacama Desert, Chile

    NASA Astrophysics Data System (ADS)

    Cereceda, P.; Larrain, H.; Osses, P.; Farías, M.; Egaña, I.

    2008-03-01

    In the Atacama Desert, the narrow littoral plain and the adjacent mountain range have a unique climate. This area is locally called the "coastal desert with abundant cloudiness", and extends from the coastline up to an elevation of 1000 m. The climate is designated as being BWn according to Köppen's Climate Classification as adapted for Chile. In the original classification the acronym (Bn) is used for foggy environments. Toward the east a "normal desert" climate (BW) is found. This is known as one of the most extreme deserts of the world. In the BWn areas there are meteorological differences between low and high elevation zones. The climate of the coastal plains and the mountains is described in this paper in order to show that there is an area where the climate differs from those classified as BWn and BW in the Chilean Climate Classification. This area is located between 650 and 1200 m a.s.l. and contains several fog oases or lomas vegetation, rich in biodiversity and endemism. The weather is warmer near sea level, with an annual average temperature of 18 °C. At high elevation sites like Alto Patache, the temperature decreases at a rate of 0.7 °C for every 100-m increase in altitude. The average annual minimum temperature often approaches 1 °C in winter, while the mean annual temperature range is significant (8.3 °C in Los Cóndores). The mean monthly relative humidity in Alto Patache is over 80%, except during the summer months. During autumn, winter and spring high elevation fog is present in the study area at altitudes ranging from 650 m up to 1060 m, giving annual water yields of 0.8 to 7 L m - 2 day - 1 . If vegetation is used as an indicator, the foggy zone lies between 650 m a.s.l. and 1200 m a.s.l. About 70% of the mountain range experiences the foggy climate, as opposed to the coastal plains that are characterized by a cloudy climate.

  13. Evaluation of factors affecting soil carbon sequestration services of stormwater wet retention ponds in varying climate zones.

    PubMed

    Merriman, L S; Moore, T L C; Wang, J W; Osmond, D L; Al-Rubaei, A M; Smolek, A P; Blecken, G T; Viklander, M; Hunt, W F

    2017-04-01

    The carbon sequestration services of stormwater wet retention ponds were investigated in four different climates: U.S., Northern Sweden, Southern Sweden, and Singapore, representing a range of annual mean temperatures, growing season lengths and rainfall depths: geographic factors that were not statistically compared, but have great effect on carbon (C) accumulation. A chronosequence was used to estimate C accumulations rates; C accumulation and decomposition rates were not directly measured. C accumulated significantly over time in vegetated shallow water areas (0-30cm) in the USA (78.4gCm(-2)yr(-1)), in vegetated temporary inundation zones in Sweden (75.8gCm(-2)yr(-1)), and in all ponds in Singapore (135gCm(-2)yr(-1)). Vegetative production appeared to exert a stronger influence on relative C accumulation rates than decomposition. Comparing among the four climatic zones, the effects of increasing rainfall and growing season lengths (vegetative production) outweighed the effects of higher temperature on decomposition rates. Littoral vegetation was a significant source to the soil C pool relative to C sources draining from watersheds. Establishment of vegetation in the shallow water zones of retention ponds is vital to providing a C source to the soil. Thus, the width of littoral shelves containing this vegetation along the perimeter may be increased if C sequestration is a design goal. This assessment establishes that stormwater wet retention ponds can sequester C across different climate zones with generally annual rainfall and lengths of growing season being important general factors for C accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Climate

    NASA Astrophysics Data System (ADS)

    Lunine, J.; Murdin, P.

    2000-11-01

    Earth's climate may be defined as the global physical condition, averaged over some period of time (typically decades or longer), of the EARTH'S ATMOSPHERE, OCEAN and ice sheets. It is the presence of a relatively dense atmosphere—third among the solid bodies of the solar system—that makes Earth habitable. Without the blanketing of infrared energy radiated from Earth's surface and lower atmospher...

  15. Climate variability, precipitation trends, and impacts on surface processes in humid to arid climate transition zones of the NW Argentine Andes (24° S, 65° W)

    NASA Astrophysics Data System (ADS)

    Castino, Fabiana; Bookhagen, Bodo; Strecker, Manfred

    2015-04-01

    In the Andes of NW Argentina the distribution and amount of rainfall and associated surface processes are intimately correlated with pronounced topographic gradients and relief contrasts that intercept easterly moisture-bearing winds related to the South American Monsoon System. These conditions have led to a pronounced elevation-dependent distribution of rainfall, which involves areally limited transition zones between the humid eastern flanks of the orogen (eastern foreland and eastern flanks of the E Cordillera) and the arid orogen interior (Puna Plateau). At interannual scales rainfall patterns in this area can be modulated by different atmospheric disturbances, such as the South Atlantic Convergent Zone and the El Niño Southern Oscillation, resulting in drought or flooding events. During the last two decades, field observations document fluvial aggradation in many intermontane valleys along the eastern flanks of the orogen. This may be related to changing overall climatic conditions, impacting hillslope erosion processes at high elevation, but contemporaneously overwhelming the fluvial system and reducing transport capacity, leading to transient sediment storage. We analyzed rainfall trends in the humid to arid climatic transition zone in the NW Argentine Andes over different time periods to characterize the spatiotemporal variability of rainfall patterns during the last five decades. We relied on both daily ground station (40 stations, 1956-2012) and three-hourly remote sensing rainfall data (3B42 V7 TRMM data, 1998-2014). Seasonal total anomalies analysis shows a complex rainfall pattern, reflected both in station data and remote sensing observations with clear positive (negative) statistically significant trends in the northern Puna Plateau and in the northern part of the foreland basin (southern part of the eastern foreland basin) of up to +20mm/yr (-20mm/yr). Quantile regression of three-hourly and daily data furthermore shows that, on average

  16. Global Climate Change and Its Potential Impact on Disease Transmission by Salinity-Tolerant Mosquito Vectors in Coastal Zones

    PubMed Central

    Ramasamy, Ranjan; Surendran, Sinnathamby Noble

    2012-01-01

    Global climate change can potentially increase the transmission of mosquito vector-borne diseases such as malaria, lymphatic filariasis, and dengue in many parts of the world. These predictions are based on the effects of changing temperature, rainfall, and humidity on mosquito breeding and survival, the more rapid development of ingested pathogens in mosquitoes and the more frequent blood feeds at moderately higher ambient temperatures. An expansion of saline and brackish water bodies (water with <0.5 ppt or parts per thousand, 0.5–30 ppt and >30 ppt salt are termed fresh, brackish, and saline respectively) will also take place as a result of global warming causing a rise in sea levels in coastal zones. Its possible impact on the transmission of mosquito-borne diseases has, however, not been adequately appreciated. The relevant impacts of global climate change on the transmission of mosquito-borne diseases in coastal zones are discussed with reference to the Ross–McDonald equation and modeling studies. Evidence is presented to show that an expansion of brackish water bodies in coastal zones can increase the densities of salinity-tolerant mosquitoes like Anopheles sundaicus and Culex sitiens, and lead to the adaptation of fresh water mosquito vectors like Anopheles culicifacies, Anopheles stephensi, Aedes aegypti, and Aedes albopictus to salinity. Rising sea levels may therefore act synergistically with global climate change to increase the transmission of mosquito-borne diseases in coastal zones. Greater attention therefore needs to be devoted to monitoring disease incidence and preimaginal development of vector mosquitoes in artificial and natural coastal brackish/saline habitats. It is important that national and international health agencies are aware of the increased risk of mosquito-borne diseases in coastal zones and develop preventive and mitigating strategies. Application of appropriate counter measures can greatly reduce the potential for

  17. Global climate change and its potential impact on disease transmission by salinity-tolerant mosquito vectors in coastal zones.

    PubMed

    Ramasamy, Ranjan; Surendran, Sinnathamby Noble

    2012-01-01

    Global climate change can potentially increase the transmission of mosquito vector-borne diseases such as malaria, lymphatic filariasis, and dengue in many parts of the world. These predictions are based on the effects of changing temperature, rainfall, and humidity on mosquito breeding and survival, the more rapid development of ingested pathogens in mosquitoes and the more frequent blood feeds at moderately higher ambient temperatures. An expansion of saline and brackish water bodies (water with <0.5 ppt or parts per thousand, 0.5-30 ppt and >30 ppt salt are termed fresh, brackish, and saline respectively) will also take place as a result of global warming causing a rise in sea levels in coastal zones. Its possible impact on the transmission of mosquito-borne diseases has, however, not been adequately appreciated. The relevant impacts of global climate change on the transmission of mosquito-borne diseases in coastal zones are discussed with reference to the Ross-McDonald equation and modeling studies. Evidence is presented to show that an expansion of brackish water bodies in coastal zones can increase the densities of salinity-tolerant mosquitoes like Anopheles sundaicus and Culex sitiens, and lead to the adaptation of fresh water mosquito vectors like Anopheles culicifacies, Anopheles stephensi, Aedes aegypti, and Aedes albopictus to salinity. Rising sea levels may therefore act synergistically with global climate change to increase the transmission of mosquito-borne diseases in coastal zones. Greater attention therefore needs to be devoted to monitoring disease incidence and preimaginal development of vector mosquitoes in artificial and natural coastal brackish/saline habitats. It is important that national and international health agencies are aware of the increased risk of mosquito-borne diseases in coastal zones and develop preventive and mitigating strategies. Application of appropriate counter measures can greatly reduce the potential for increased

  18. Air Flow Path Dynamics In The Vadose Zone Under Various Land Surface Climate Boundary Conditions

    NASA Astrophysics Data System (ADS)

    Illangasekare, T. H.; Sakaki, T.; Schulte, P. E.; Cihan, A.; Christ, J.

    2010-12-01

    Vapor intrusion (VI) refers to the transport of volatile chemical vapors from subsurface sources to surface and subsurface structures through the vadose zone. Because of the difference in pressure between the inside of the building and the subsurface soil pores, vapor can enter the building through cracks in the foundation, slab and walls and utility openings. The processes that govern the vapor transport in the heterogeneous subsurface “outside the home” are complex, and the sampling to assess potential pathways is subjected to spatial and temporal variability. Spatial variability is a result of a number of factors that include changing soil and soil moisture conditions. Temporal variability is a result of transient heat, wind, ambient pressure and a water flux boundary conditions at the land-atmospheric interface. Fluctuating water table conditions controlled by recharge, pumping, and stream-aquifer interactions will also contribute to the transient vapor flux generation at the sources. When the soil moisture changes as a result of precipitation events and other soil surface boundary conditions, the soil moisture content changes and hence the air permeability. Therefore, the primary pathways for the vapor are preferential channels that change with the transient soil moisture distribution. Both field and laboratory studies have shown that heterogeneity has a significant influence on soil moisture conditions in unsaturated soils. Uncertainties in vapor transport predictions have been attributed to heterogeneity and spatial variability in hydraulic properties. In this study, our goal was to determine the role of soil moisture variability on vapor transport and intrusion as affected by the climate driven boundary conditions on the land surface. A series of experiments were performed to generate a comprehensive data set to understand and evaluate how the spatial and temporal variability of soil moisture affected by the mass and heat flux boundary conditions on the

  19. New Definitions for the Inner Edge of the Habitable Zone Around M-Dwarf Stars from 3D Climate Models.

    NASA Astrophysics Data System (ADS)

    Wolf, E. T.; Haqq-Misra, J. D.; Kopparapu, R.

    2016-12-01

    M-dwarf systems provide several compelling motivations for study. M-dwarf stars are the most numerous, evolve slowly on the main sequence, and are the most amenable targets for detecting and characterizing extrasolar planets. Furthermore, planets within the habitable zone of M-dwarf stars will be tidally locked. This feature imposes a profound control on planetary climate. The planetary rotation rate, incident stellar flux, and spectral energy distribution become inextricably linked by the orbital configuration of the system. Atmospheric dynamics, convection, clouds, and shortwave absorption by water vapor all are fundamentally affected. Here, we use the Community Earth System Model (CESM) from the National Center for Atmospheric Research, with important improvements to the radiative transfer and numerical stability, to determine the inner edge of the habitable zone for Earth-like planets orbiting M-dwarf stars. We study systems with host star effective temperatures between 2600 K and 4500 K, and over a wide range of incident stellar fluxes. We discern between both runaway and moist greenhouse limits to the inner edge of the habitable zone. We will also discuss the relevant climatic feedback mechanisms at play.

  20. Emission of methyl chloride from a fern growing in subtropical, temperate, and cool-temperate climate zones

    NASA Astrophysics Data System (ADS)

    Yokouchi, Yoko; Takenaka, Akio; Miyazaki, Yuzo; Kawamura, Kimitaka; Hiura, Tsutom

    2015-06-01

    Tropical and subtropical forests are believed to be the largest source of methyl chloride (CH3Cl), which is a natural stratospheric ozone destroyer. However, very little is known about what controls the rate of emission from these forests or why biogenic CH3Cl emission is concentrated in the tropics and subtropics. In this study, we investigated the seasonal and spatial variations of the rate of CH3Cl emission from the fern Osmunda japonica, which has a broad distribution covering the subtropical, temperate, and subboreal climate zones. The average rates of CH3Cl emission from the fern were similar (~1-4 µg g(dw)-1 h-1) among three areas, and there was no significant seasonal change in the temperate zone, although the rate was highly variable among individual plants. These findings suggest that meteorological climate such as temperature and solar radiation is not a major environmental factor controlling biogenic CH3Cl emission of individual plants, but species with high CH3Cl emission activity are more abundant in tropical and subtropical zones. We also found that developmental stage might be an important factor controlling biogenic CH3Cl emission rates. These results have implications for predicting future global CH3Cl emission budgets and for understanding of the plant-atmosphere interaction.

  1. Patterns of Genetic and Morphometric Diversity in Baobab (Adansonia digitata) Populations Across Different Climatic Zones of Benin (West Africa)

    PubMed Central

    ASSOGBADJO, A. E.; KYNDT, T.; SINSIN, B.; GHEYSEN, G.; VAN DAMME, P.

    2006-01-01

    • Background and Aims Baobab (Adansonia digitata) is a multi-purpose tree used daily by rural African communities. The present study aimed at investigating the level of morphometric and genetic variation and spatial genetic structure within and between threatened baobab populations from the three climatic zones of Benin. • Methods A total of 137 individuals from six populations were analysed using morphometric data as well as molecular marker data generated using the AFLP technique. • Key Results Five primer pairs resulted in a total of 217 scored bands with 78·34 % of them being polymorphic. A two-level AMOVA of 137 individuals from six baobab populations revealed 82·37 % of the total variation within populations and 17·63 % among populations (P < 0·001)· Analysis of population structure with allele-frequency based F-statistics revealed a global FST of 0·127 ± 0·072 (P < 0·001). The mean gene diversity within populations (HS) and the average gene diversity between populations (DST) were estimated at 0·309 ± 0·000 and 0·045 ± 0·072, respectively. Baobabs in the Sudanian and Sudan-Guinean zones of Benin were short and produced the highest yields of pulp, seeds and kernels, in contrast to the ones in the Guinean zone, which were tall and produced only a small number of fruits with a low pulp, seed and kernel productivity. A statistically significant correlation with the observed patterns of genetic diversity was observed for three morphological characteristics: height of the trees, number of branches and thickness of the capsules. • Conclusions The results indicate some degree of physical isolation of the populations collected in the different climatic zones and suggest a substantial amount of genetic structuring between the analysed populations of baobab. Sampling options of the natural populations are suggested for in or ex situ conservation. PMID:16520343

  2. Spatial Variability of Climate Signatures Recorded in an Array of Shallow Firn Cores from the Western Greenland Percolation Zone

    NASA Astrophysics Data System (ADS)

    Thundercloud, Z. R.; Osterberg, E. C.; Ferris, D. G.; Graeter, K.; Lewis, G.; Hawley, R. L.; Marshall, H. P.

    2016-12-01

    Greenland ice cores provide seasonally to annually resolved proxy records of past temperature, accumulation and atmospheric circulation. Most Greenland ice cores have been collected from the dry snow zone at elevations greater than 2500 m to produce records of North Atlantic paleoclimate over the last full glacial cycle. Ice cores collected from more costal regions, however, provide the opportunity to develop regional-scale records of climate conditions along ice sheet margins where recent temperature and precipitation changes have been larger than those in the ice sheet interior. These cores are more readily comparable to lake sediment and landscape (i.e. moraine) records from the ice sheet margin, and are potentially more sensitive to sea-ice variability due to the proximity to the coast. Here we present major ion and stable isotope records from an array of firn cores (40-55 year records) collected in the western Greenland percolation zone, and assess the spatial variability of ice core statistical relationships with the North Atlantic Oscillation (NAO) and Baffin Bay sea ice extent. Seven cores were collected from elevations of 2100-2500 m along a 400-km segment of the ice sheet from Dye-2 to Milcent as part of the Greenland Traverse for Accumulation and Climate Studies (GreenTrACS) project from May-June 2016. They were sampled by a continuous melter system at Dartmouth College, and analyzed using Dionex ion chromatographs and a Picarro L2130-i laser ring-down spectrometer. We focus on the signature of the NAO and Baffin Bay sea ice extent in the sea-salt, dust, deuterium excess (d-excess), and methanesulfonic acid (MSA) firn core records, and assess the special variability of these climate-ice core relationships across the study area. Climate reanalysis data indicate that NAO-ice core correlations should be stronger at lower elevation in the percolation zone than high in the dry snow zone. Our results will provide valuable insight into the sensitivity of

  3. Evaluating the patterns of spatiotemporal trends of root zone soil moisture in major climate regions in East Asia

    NASA Astrophysics Data System (ADS)

    Zohaib, Muhammad; Kim, Hyunglok; Choi, Minha

    2017-08-01

    Root zone soil moisture (RZSM) is a crucial variable in land-atmosphere interactions. Evaluating the spatiotemporal trends and variability patterns of RZSM are essential for discerning the anthropogenic and climate change effects on the regional and global hydrological cycles. In this study, the trends of RZSM, computed by the exponential filter from the European Space Agency's Climate Change Initiative soil moisture, were evaluated in major climate regions of East Asia from 1982 to 2014. Moreover, the trends of RZSM were compared to the trends of precipitation (P), skin temperature (Tskin), and actual evapotranspiration (AET) to investigate how they influence the RZSM trends in each climate region. Drying trends were predominant in arid and continental regions, whereas wetting trends were found in the tropical and temperate regions. The increasing trends of Tskin and AET cause drying in arid and continental regions, whereas in tropical regions, these cause wetting trends, which might be due to convective P. In temperate regions, despite decreasing P and increasing Tskin, the RZSM trend was increasing, attributed to the intensive irrigation activities in these regions. This is probably the first time to analyze the long-term trends of RZSM in different climate regions. Hence, the results of this study will improve our understanding of the regional and global hydrological cycles. Despite certain limitations, the results of this study may be useful for improving and developing climate models and predicting long-term vast scale natural disasters such as drought, dust outbreaks, floods, and heat waves.

  4. Halotolerant, alkaliphilic urease-producing bacteria from different climate zones and their application for biocementation of sand.

    PubMed

    Stabnikov, Viktor; Chu, Jian; Jian, Chu; Ivanov, Volodymyr; Li, Yishan

    2013-08-01

    Microbially induced calcium carbonate precipitation (MICP) is a phenomenon based on urease activity of halotolerant and alkaliphilic microorganisms that can be used for the soil bioclogging and biocementation in geotechnical engineering. However, enrichment cultures produced from indigenous soil bacteria cannot be used for large-scale MICP because their urease activity decreased with the rate about 5 % per one generation. To ensure stability of urease activity in biocement, halotolerant and alkaliphilic strains of urease-producing bacteria for soil biocementation were isolated from either sandy soil or high salinity water in different climate zones. The strain Bacillus sp. VUK5, isolated from soil in Ukraine (continental climate), was phylogenetically close in identity (99 % of 16S rRNA gene sequence) to the strain of Bacillus sp. VS1 isolated from beach sand in Singapore (tropical rainforest climate), as well as to the strains of Bacillus sp. isolated by other researchers in Ghent, Belgium (maritime temperate climate) and Yogyakarta, Indonesia (tropical rainforest climate). Both strains Bacillus sp. VS1 and VUK5 had maximum specific growth rate of 0.09/h and maximum urease activities of 6.2 and 8.8 mM of hydrolysed urea/min, respectively. The halotolerant and alkaliphilic strain of urease-producing bacteria isolated from water of the saline lake Dead Sea in Jordan was presented by Gram-positive cocci close to the species Staphylococcus succinus. However, the strains of this species could be hemolytic and toxigenic, therefore only representatives of alkaliphilic Bacillus sp. were used for the biocementation studies. Unconfined compressive strengths for dry biocemented sand samples after six batch treatments with strains VS1and VUK5 were 765 and 845 kPa, respectively. The content of precipitated calcium and the strength of dry biocemented sand at permeability equals to 1 % of initial value were 12.4 g Ca/kg of dry sand and 454 kPa, respectively, in case of

  5. Absolute humidity and the human nose: A reanalysis of climate zones and their influence on nasal form and function.

    PubMed

    Maddux, Scott D; Yokley, Todd R; Svoma, Bohumil M; Franciscus, Robert G

    2016-10-01

    Investigations into the selective role of climate on human nasal variation commonly divide climates into four broad adaptive zones (hot-dry, hot-wet, cold-dry, and cold-wet) based on temperature and relative humidity. Yet, absolute humidity-not relative humidity-is physiologically more important during respiration. Here, we investigate the global distribution of absolute humidity to better clarify ecogeographic demands on nasal physiology. We use monthly observations from the Climatic Research Unit Timeseries 3 (CRU TS3) database to construct global maps of average annual temperature, relative humidity and absolute humidity. Further, using data collected by Thomson and Buxton (1923) for over 15,000 globally-distributed individuals, we calculate the actual amount of heat and water that must be transferred to inspired air in different climatic regimes to maintain homeostasis, and investigate the influence of these factors on the nasal index. Our results show that absolute humidity, like temperature, generally decreases with latitude. Furthermore, our results demonstrate that environments typically characterized as "cold-wet" actually exhibit low absolute humidities, with values virtually identical to cold-dry environments and significantly lower than hot-wet and even hot-dry environments. Our results also indicate that strong associations between the nasal index and absolute humidity are, potentially erroneously, predicated on individuals from hot-dry environments possessing intermediate (mesorrhine) nasal indices. We suggest that differentially allocating populations to cold-dry or cold-wet climates is unlikely to reflect different selective pressures on respiratory physiology and nasal morphology-it is cold-dry, and to a lesser degree hot-dry environments, that stress respiratory function. Our study also supports assertions that demands for inspiratory modification are reduced in hot-wet environments, and that expiratory heat elimination for thermoregulation is a

  6. Backyard of the rich north: the climate change-related vicious circle of the Arctic zone.

    PubMed

    Varis, Olli

    2006-06-01

    The Arctic zone is full of controversies, unknowns, contrasts, and challenges. The following example is enlightening. Saudi Arabia is a country that has been considered to have almost unlimited possibilities because of its enormous oil earnings. The country has US$60 thousand million purchasing power parity oil income each year for its mere 22 million inhabitants. Astonishingly, the Arctic zone's income from oil, gas, and minerals is at least as large as that of Saudi Arabia, modestly estimated, but the Arctic has less than 4 million people. Most money, however, flows away from the tundra, yet social and environmental problems remain there. A part of the side effect of consuming these resources-largely fossil fuels-returns to the Arctic in the form of greenhouse warming and all its consequences. The Arctic zone now warms at approximately double the rate of the world average.

  7. Spatial Change in the Geometry and Kinematics of the Trinity River, TX, USA, Defining the Morphodynamics of the Fluvial Coastal Zone

    NASA Astrophysics Data System (ADS)

    Mohrig, D. C.; Smith, V. B.; Mason, J.

    2015-12-01

    Changes to the geomorphology of meandering rivers as they approach the coast are now recognized as being connected to a transition from quasi-normal flow upstream to a zone of gradually varying flow near the shoreline. In spite of this recognition, there remains a great deal to learn regarding the morphodynamics of coastal rivers. Here we present data from repeat bathymetric and topographic surveys, aerial photo analyses, and bed-material sampling that are aimed at defining the morphodynamics of the coastal Trinity River. Initial change in the geomorphology of the river channel is coincident with the average elevation of the river bottom dropping below mean sea level. Over the next 50 river km downstream of this point, the vegetated channel width systematically decreases by 44 percent and channel depth systematically increases 1.95 times. The net result is a 66 percent reduction in the width-to-depth ratio, which is not evenly distributed in the downstream direction. All of the change occurs in the first 28 river km, with the channel maintaining a statistically constant value of 17 for the next 22 river km. The size of point bars also begins to systemically decrease at the point where the river bottom drops below sea level. Over the next 50 river km the surface area of these bars decreases by an order of magnitude. This substantial reduction is not only a function of the decrease in channel width, but also a decrease in point-bar length. At about 23 km downstream the bars undergo a change in their cross-sectional shape. Upstream they occupy roughly 80 percent of the channel, while downstream they occupy only 70 percent of the channel width. This coincides with the point where lateral migration rates for channel bends drop by roughly 75 percent. We show how these changes in channel geometry and kinematics are connected to time and space changes in hydrology and sediment transport in the backwater zone.

  8. Zoning vulnerability of climate change in variation of amount and trend of precipitation - Case Study: Great Khorasan province

    NASA Astrophysics Data System (ADS)

    Modiri, Ehsan; Modiri, Sadegh

    2015-04-01

    meteorological perspective risk. Finally, after determining the degree of threats, meteorological vulnerability zoning map was produced by kriging interpolation method and utilizing geographic information systems (GIS). It showed most studied areas were in complete level of investigation. Keywords: Vulnerability, Climate threats, GIS, Zoning, Precipitation, Crisis management.

  9. Finding Queer Allies: The Impact of Ally Training and Safe Zone Stickers on Campus Climate

    ERIC Educational Resources Information Center

    Ballard, Stephanie L.; Bartle, Eli; Masequesmay, Gina

    2008-01-01

    To counter heterosexism, homophobia, and gender binarism in higher education, "safe zone" or "ally" programs are efforts by American universities to create a welcoming environment for lesbian, gay, bisexual, transgender, queer or questioning (LGBTQ) members of the campus community. This study describes perceptions of campus…

  10. The Impact of an LGBT Safe Zone Project on Campus Climate.

    ERIC Educational Resources Information Center

    Evans, Nancy J.

    2002-01-01

    A critical ethnographic evaluation was conducted to assess the impact of a Lesbian, Gay, Bisexual, and Transgender (LGBT) Safe Zone project. Results of the study suggest that the project has had a positive impact on the visibility of LGBT people and issues on campus, and has increased support for LGBT people. (Contains 17 references.) (Author)

  11. Shallow aquifer response to climate change scenarios in a small catchment in the Guarani Aquifer outcrop zone.

    PubMed

    Melo, Davi C D; Wendland, Edson

    2017-05-01

    Water availability restrictions are already a reality in several countries. This issue is likely to worsen due to climate change, predicted for the upcoming decades. This study aims to estimate the impacts of climate change on groundwater system in the Guarani Aquifer outcrop zone. Global Climate Models (GCM) outputs were used as inputs to a water balance model, which produced recharge estimates for the groundwater model. Recharge was estimated across different land use types considering a control period from 2004 to 2014, and a future period from 2081 to 2099. Major changes in monthly rainfall means are expected to take place in dry seasons. Most of the analysed scenarios predict increase of more than 2 ºC in monthly mean temperatures. Comparing the control and future runs, our results showed a mean recharge change among scenarios that ranged from ~-80 to ~+60%, depending on the land use type. As a result of such decrease in recharge rates, the response given by the groundwater model indicates a lowering of the water table under most scenarios.

  12. The Arab Vernacular Architecture and its Adaptation to Mediterranean Climatic Zones

    NASA Astrophysics Data System (ADS)

    Paz, Shlomit; Hamza, Efat

    2014-05-01

    Throughout history people have employed building strategies adapted to local climatic conditions in an attempt to achieve thermal comfort in their homes. In the Mediterranean climate, a mixed strategy developed - utilizing positive parameters (e.g. natural lighting), while at the same time addressing negative variables (e.g. high temperatures during summer). This study analyzes the adaptation of construction strategies of traditional Arab houses to Mediterranean climatic conditions. It is based on the assumption that the climate of the eastern Mediterranean led to development of unique architectural patterns. The way in which the inhabitants chose to build their homes was modest but creative in the context of climate awareness, with simple ideas. These were often instinctive responses to climate challenges. Nine traditional Arab houses, built from the mid-19th century to the beginning of the 20th century, were analyzed in three different regions in Israel: the "Meshulash" - an area in the center of the country, and the Lower and Upper Galilees (in the north). In each region three houses were examined. It is important to note that only a few houses from these periods still remain, particularly in light of new construction in many of the villages' core areas. Qualitative research methodologies included documentation of all the elements of these traditional houses which were assumed to be a result of climatic factors, such as - house position (direction), thickness of walls, thermal mass, ceiling height, location of windows, natural ventilation, exterior wall colors and shading strategies. Additionally, air temperatures and relative humidity were measured at selected dates throughout all seasons both inside and immediately outside the houses during morning, noon, evening and night-time hours. The documentation of the architectural elements and strategies demonstrate that climatic considerations were an integral part of the planning and construction process of these

  13. Climatic Zones, Soil Moisture Seasonality and Biomass Burning and Their Influence On Ozone Precursor Concentrations Over West Africa as Retrieved from Satellites

    NASA Astrophysics Data System (ADS)

    Onojeghuo, A. R.; Balzter, H.; Monks, P. S.

    2015-12-01

    West Africa is a region with six different climatic zones including a rich savannah affected by biomass burning annually, the Niger delta oil producing region with major gas flaring sites and a long coastline. Research on atmospheric pollution using remotely sensed data over West Africa has mostly been conducted at regional scale or for individual countries, with little emphasis on the dynamics of climatic zones and the diversity of land cover types. This study analyses annual seasonal dynamics of emissions of two ozone precursors stratified by climatic zone: nitrogen dioxide (NO2) from OMI and carbon monoxide (CO) from TES. The different sources of these pollutants and their seasonality are explicitly considered. Results indicate that the highest annual wet season NO2 column concentrations were in the semi-arid zone (1.33 x 1015 molecules cm-2) after prolonged periods of low soil moisture while the highest dry season were observed in the wet sub-humid zone (2.62 x 1015 molecules cm-2) where the savannah fires occur annually. The highest annual CO concentrations (> 3.1 x 1018 molecules cm-2) were from the Niger Delta, located in the humid zone. There were indications of atmospheric transport of CO from the southern hemisphere in the west season. Climate change induced soil moisture variability was most prominent in the dry sub-humid and semi-arid climatic zones (±0.015m3m-3) . The causal effects of soil moisture variability on NO2 emissions and their seasonal cycles were tested using the Granger causality test. Causal effects of inter-zonal exchanges/transport of NO2 and CO emissions respectively were inferred using Directed Acyclic Graphs. The results indicate that NO2, CO and their seasonal ratios are strongly affected by changes in soil moisture.

  14. Using crowdsourced data from citizen weather stations to analyse air temperature in 'local climate zones' in Berlin, Germany

    NASA Astrophysics Data System (ADS)

    Fenner, Daniel; Meier, Fred; Bechtel, Benjamin; Otto, Marco; Scherer, Dieter

    2017-04-01

    Provision of observational data with high spatial coverage over extended time periods still remains as one of the biggest challenges in urban climate research. Classical meteorological networks are seldomly designed to monitor atmospheric conditions in a broad variety of urban environments, though the heterogeneity of urban structures leads to distinct thermal characteristics on local scales, i.e., hundreds of metres to several kilometres. One approach to overcome the aforementioned challenges of observation networks is to use data from weather stations that are maintained by citizens. The private company 'netatmo' (www.netatmo.com) produces and distributes such citizen weather stations (CWS) around the world. The stations automatically send their data to the netatmo server, and the user decides if data are publicly shared. Shared data can freely be retrieved via an application programming interface. We collected air temperature (T) data for the year 2015 for the city of Berlin, Germany, and surroundings with more than 1500 'netatmo' CWS in the study area. The entire data set was thoroughly quality checked, and filter techniques, involving data from a reference network, were developed to address different types of errors associated with CWS data. Additionally, the accuracy of 'netatmo' CWS was checked in a climate chamber and in a long-term field experiment. Since the terms 'urban' and 'rural' are ambiguous in urban climate studies, Stewart and Oke (2012) developed the 'local climate zone' (LCZ) concept to enhance understanding and interpretation of air temperature differences in urban regions. LCZ classification for the study region was conducted using the 'WUDAPT' approach by Bechtel et al. (2015). The quality-checked CWS data were used to analyse T characteristics of LCZ classes in Berlin and surroundings. Specifically, we analysed how LCZ classes are represented by CWS in 2015, how T varies within each LCZ class ('intra-LCZ variability'), and if significant

  15. Impacts of Severe Weather, Climate Zone, and Energy Factors on Base Realignment and Closure (BRAC)

    DTIC Science & Technology

    2015-03-26

    necessary for weapon modernization and improved readiness. Cost savings through BRAC can help the Air Force achieve reduced spending and realign itself to...throughout the process. To Colonel Jonathan Webb and Mr. Tim Brennan of SAF/IEI – thank you for your help and insight into the BRAC process and all...weather data requests and providing sound reasoning into the anomalies I discovered in some of the climate and weather records. Thank you to all my GEM

  16. Late Quaternary Climate and Vegetation of the Sudanian Zone of Northeast Nigeria

    NASA Astrophysics Data System (ADS)

    Salzmann, Ulrich; Hoelzmann, Philipp; Morczinek, Irena

    2002-07-01

    The Lake Tilla crater lake in northeastern Nigeria (10°23'N, 12°08'E) provides a ca. 17,000 14C yr multiproxy record of the environmental history of a Sudanian savanna in West Africa. Evaluation of pollen, diatoms, and sedimentary geochemistry from cores suggests that dry climatic conditions prevailed throughout the late Pleistocene. Before the onset of the Holocene, the slow rise in lake levels was interrupted by a distinct dry event between ca. 10,900 and 10,500 14C yr B.P., which may coincide with the Younger Dryas episode. The onset of the Holocene is marked by an abrupt increase in lake levels and a subsequent spread of Guinean and Sudanian tree taxa into the open grass savanna that predominated throughout the Late Pleistocene. The dominance of the mountain olive Olea hochstetteri suggests cool climatic conditions prior to ca. 8600 14C yr B.P. The early to mid-Holocene humid period culminated between ca. 8500 and 7000 14C yr B.P. with the establishment of a dense Guinean savanna during high lake levels. Frequent fires were important in promoting the open character of the vegetation. The palynological and palaeolimnological data demonstrate that the humid period terminated after ca. 7000 14C yr B.P. in a gradual decline of the precipitation/evaporation ratio and was not interrupted by abrupt climatic events. The aridification trend intensified after ca. 3800 14C yr B.P. and continued until the present.

  17. Fresh water blue green algae from three agro-climatic zones of Uttar Pradesh, India: distribution pattern with seasonal variation.

    PubMed

    Dwivedi, S; Misra, P K; Rai, U N; Tripathi, R D; Suseela, M R; Sinha, S; Baghel, V S; Pal, Amit; Dwivedi, C P

    2005-01-01

    The paper deals with 45 species of 21 genera of fresh water blue green algae (BGA) from three different agro-climatic zones of Uttar Pradesh. Samples were collected from different habitats varying in physico-chemical properties. Out of 45 species, 13 species belonged to order Chroococcales, 31 to order Nostocales, while only 1 species belonged to order Stigonimatales i.e. Fischerella mucicola. The physico-chemical parameters like pH, temperature, dissolved oxygen, electrical conductivity, nitrate, nitrite and rainfall play an important role in the periodicity of BGA. A positive correlation was found between dissolved oxygen (DO) of different ponds and species diversity, except in the case of western region of Uttar Pradesh (Farukhabad and Mahoba districts) where a positive correlation was found in electrical conductivity and total dissolved solids.

  18. Distributions of Fecal Markers in Wastewater from Different Climatic Zones for Human Fecal Pollution Tracking in Australian Surface Waters.

    PubMed

    Ahmed, W; Sidhu, J P S; Smith, K; Beale, D J; Gyawali, P; Toze, S

    2015-12-18

    Recreational and potable water supplies polluted with human wastewater can pose a direct health risk to humans. Therefore, sensitive detection of human fecal pollution in environmental waters is very important to water quality authorities around the globe. Microbial source tracking (MST) utilizes human fecal markers (HFMs) to detect human wastewater pollution in environmental waters. The concentrations of these markers in raw wastewater are considered important because it is likely that a marker whose concentration is high in wastewater will be more frequently detected in polluted waters. In this study, quantitative PCR (qPCR) assays were used to determine the concentrations of fecal indicator bacteria (FIB) Escherichia coli and Enterococcus spp., HFMs Bacteroides HF183, human adenoviruses (HAdVs), and polyomaviruses (HPyVs) in raw municipal wastewater influent from various climatic zones in Australia. E. coli mean concentrations in pooled human wastewater data sets (from various climatic zones) were the highest (3.2 × 10(6) gene copies per ml), followed by those of HF183 (8.0 × 10(5) gene copies per ml) and Enterococcus spp. (3.6 × 10(5) gene copies per ml). HAdV and HPyV concentrations were 2 to 3 orders of magnitude lower than those of FIB and HF183. Strong positive and negative correlations were observed between the FIB and HFM concentrations within and across wastewater treatment plants (WWTPs). To identify the most sensitive marker of human fecal pollution, environmental water samples were seeded with raw human wastewater. The results from the seeding experiments indicated that Bacteroides HF183 was more sensitive for detecting human fecal pollution than HAdVs and HPyVs. Since the HF183 marker can occasionally be present in nontarget animal fecal samples, it is recommended that HF183 along with a viral marker (HAdVs or HPyVs) be used for tracking human fecal pollution in Australian environmental waters.

  19. Current genetic differentiation of Coffea canephora Pierre ex A. Froehn in the Guineo-Congolian African zone: cumulative impact of ancient climatic changes and recent human activities

    PubMed Central

    Gomez, Céline; Dussert, Stéphane; Hamon, Perla; Hamon, Serge; Kochko, Alexandre de; Poncet, Valérie

    2009-01-01

    Background Among Coffea species, C. canephora has the widest natural distribution area in tropical African forests. It represents a good model for analyzing the geographical distribution of diversity in relation to locations proposed as part of the "refuge theory". In this study, we used both microsatellite (simple sequence repeat, SSR) and restriction fragment length polymorphism (RFLP) markers to investigate the genetic variation pattern of C. canephora in the Guineo-Congolean distribution zone. Results Both markers were first compared in terms of their informativeness and efficiency in a study of genetic diversity and relationships among wild C. canephora genotypes. As expected, SSR markers were found to have a higher genetic distance detection capacity than RFLP. Nevertheless, similarity matrices showed significant correlations when Mantel's test was carried out (r = 0.66, p < 0.0001). Finally, both markers were equally effective for group discrimination and phylogenetic studies, but SSR markers tended to outperform RFLP markers in discriminating the source of an individual among diversity groups and in putative hybrid detection. Five well defined genetic groups, one in the Upper Guinean forests, the four others in the Lower Guinean forests, were identified, corresponding to geographical patterning in the individuals. Conclusion Our data suggested that the Dahomey Gap, a biogeographical barrier, played a role in wild C. canephora differentiation. Climatic variations during the Pleistocene and/or Holocene probably caused the subgroup differentiation in the Congolese zone through the presence of a mosaic of putative refugia. Recent hybridization between C. canephora diversity groups, both for spontaneous individuals and cultivars, was further characterised according to their geographic dissemination or breeding history as a consequence of human activities. PMID:19607674

  20. Influence of climate variability on water partitioning and effective energy and mass transfer in a semi-arid critical zone

    NASA Astrophysics Data System (ADS)

    Zapata-Rios, Xavier; Brooks, Paul D.; Troch, Peter A.; McIntosh, Jennifer; Rasmussen, Craig

    2016-03-01

    The critical zone (CZ) is the heterogeneous, near-surface layer of the planet that regulates life-sustaining resources. Previous research has demonstrated that a quantification of the influxes of effective energy and mass transfer (EEMT) to the CZ can predict its structure and function. In this study, we quantify how climate variability in the last 3 decades (1984-2012) has affected water availability and the temporal trends in EEMT. This study takes place in the 1200 km2 upper Jemez River basin in northern New Mexico. The analysis of climate, water availability, and EEMT was based on records from two high-elevation SNOTEL stations, PRISM data, catchment-scale discharge, and satellite-derived net primary productivity (MODIS). Results from this study indicated a decreasing trend in water availability, a reduction in forest productivity (4 g C m-2 per 10 mm of reduction in precipitation), and decreasing EEMT (1.2-1.3 MJ m2 decade-1). Although we do not know the timescales of CZ change, these results suggest an upward migration of CZ/ecosystem structure on the order of 100 m decade-1, and that decadal-scale differences in EEMT are similar to the differences between convergent/hydrologically subsidized and planar/divergent landscapes, which have been shown to be very different in vegetation and CZ structure.

  1. Climatic drivers for multidecadal shifts in solute transport and methane production zones within a large peat basin

    NASA Astrophysics Data System (ADS)

    Glaser, Paul H.; Siegel, Donald I.; Chanton, Jeffrey P.; Reeve, Andrew S.; Rosenberry, Donald O.; Corbett, J. Elizabeth; Dasgupta, Soumitri; Levy, Zeno

    2016-11-01

    Northern peatlands are an important source for greenhouse gases, but their capacity to produce methane remains uncertain under changing climatic conditions. We therefore analyzed a 43 year time series of the pore-water chemistry to determine if long-term shifts in precipitation altered the vertical transport of solutes within a large peat basin in northern Minnesota. These data suggest that rates of methane production can be finely tuned to multidecadal shifts in precipitation that drive the vertical penetration of labile carbon substrates within the Glacial Lake Agassiz Peatlands. Tritium and cation profiles demonstrate that only the upper meter of these peat deposits was flushed by downwardly moving recharge from 1965 to 1983 during a Transitional Dry-to-Moist Period. However, a shift to a moister climate after 1984 drove surface waters much deeper, largely flushing the pore waters of all bogs and fens to depths of 2 m. Labile carbon compounds were transported downward from the rhizosphere to the basal peat at this time producing a substantial enrichment of methane in Δ14C with respect to the solid-phase peat from 1991 to 2008. These data indicate that labile carbon substrates can fuel deep production zones of methanogenesis that more than doubled in thickness across this large peat basin after 1984. Moreover, the entire peat profile apparently has the capacity to produce methane from labile carbon substrates depending on climate-driven modes of solute transport. Future changes in precipitation may therefore play a central role in determining the source strength of peatlands in the global methane cycle.

  2. Climatic drivers for multidecadal shifts in solute transport and methane production zones within a large peat basin

    USGS Publications Warehouse

    Glaser, Paul H.; Siegel, Donald I.; Chanton, Jeffrey P.; Reeve, Andrew S.; Rosenberry, Donald O.; Corbett, J. Elizabeth; Dasgupta, Soumitri; Levy, Zeno

    2016-01-01

    Northern peatlands are an important source for greenhouse gases, but their capacity to produce methane remains uncertain under changing climatic conditions. We therefore analyzed a 43 year time series of the pore-water chemistry to determine if long-term shifts in precipitation altered the vertical transport of solutes within a large peat basin in northern Minnesota. These data suggest that rates of methane production can be finely tuned to multidecadal shifts in precipitation that drive the vertical penetration of labile carbon substrates within the Glacial Lake Agassiz Peatlands. Tritium and cation profiles demonstrate that only the upper meter of these peat deposits was flushed by downwardly moving recharge from 1965 to 1983 during a Transitional Dry-to-Moist Period. However, a shift to a moister climate after 1984 drove surface waters much deeper, largely flushing the pore waters of all bogs and fens to depths of 2 m. Labile carbon compounds were transported downward from the rhizosphere to the basal peat at this time producing a substantial enrichment of methane in Δ14C with respect to the solid-phase peat from 1991 to 2008. These data indicate that labile carbon substrates can fuel deep production zones of methanogenesis that more than doubled in thickness across this large peat basin after 1984. Moreover, the entire peat profile apparently has the capacity to produce methane from labile carbon substrates depending on climate-driven modes of solute transport. Future changes in precipitation may therefore play a central role in determining the source strength of peatlands in the global methane cycle.

  3. Reaction of the accumulation zone portions of glaciers to climatic change

    SciTech Connect

    Whillans, I.M.

    1981-05-20

    The response of the accumulation regions of glaciers to changes in accumulation rate and in surface temperature is calculated by considering perturbations to the ice flow. The analysis is limited to glaciers in whch flow is dominated by internal shear and not by bottom sliding and for which flowliners are geographically paralled. In general, glaciers begin to alter thickness immediately after a change in accumulation rate, but the effect of a change in surface temperature is delayed by the time for this temperature change to penetrate to depth in the glacier. A warming leads to glacial thinning. The amount and timing of the response is very different for different glaciers. Characteristic times are on the order of tens of years for mountain glaciers and ten of thousands of years for the east antarctic ice sheet. As an example, the theory is applied to the ice sheet near Byrd Station, Antarctica. For hypothetical changes in surface accumulation rate and temperature, rates and amounts of thickness change are calculated, and it is found that the measured thinning is probably too fast to have been caused by climatic variation alone. The effects of hypothetical climatic variations on the depth-age and depth-temperature relationships through the ice sheet are also calculated. It is hoped that the theory will prove valuable in the interpreation of future drill hole results.

  4. Editorial - Climate change impacts on rural poverty in low-elevation coastal zones, Edward B. Barbier

    NASA Astrophysics Data System (ADS)

    Elliott, Michael; Wolanski, Eric

    2015-11-01

    In the Invited Feature Article in this issue of Estuarine, Coastal and Shelf Science, we are extremely grateful to Edward Barbier for performing the major task of increasing our awareness of the hazards and risks faced by all communities on low lying coasts but especially the poor, rural communities (Barbier, 2015). Against a background of climate-induced change, we now have a good and increasing evidence of the way the natural estuarine, coastal and marine system will respond (Elliott et al, 2015). However, more importantly Barbier (2015) highlights the way in which poor, rural coastal communities will be affected and will need to respond or will need help from the developed world to respond. It is axiomatic that while those communities are having less impact than more developed countries on the causes of climate change they are more affected and so have to respond to its consequences, what have been called exogenic unmanaged pressures. Hence they need to rely on mechanisms, techniques, technologies and approaches to help them cope with such change (see also Wolanski and Elliott 2015).

  5. Meningococcal meningitis and carriage in western Zaire: a hypoendemic zone related to climate?

    PubMed Central

    Cheesbrough, J. S.; Morse, A. P.; Green, S. D.

    1995-01-01

    An analysis of bacteria recovered from cerebrospinal fluid over a 16-year period at a rural hospital in western Zaire showed that Neisseria meningitidis accounted for only five (2.2%) isolates. A survey of naso-pharyngeal colonisation with N. meningitidis in 378 healthy children was undertaken to distinguish whether this low frequency was due to lack of carriage or, by inference, lack of the co-factors necessary to permit invasive disease. N. meningitidis was recovered from only three (0.78%) of the children. All isolates were non-typable strains of low pathogenicity. A review of studies examining the aetiology of bacterial meningitis and the geographical location of epidemics of meningococcal meningitis in and around Zaire reveals a 'hypoendemic zone', the limits of which correlate well with the area in which mean absolute humidity remains above 10 g m-3 of air throughout the year. Continuous high absolute humidity appears to reduce the transmission of meningococci. PMID:7867746

  6. Phylogeography of the Coastal Mosquito Aedes togoi across Climatic Zones: Testing an Anthropogenic Dispersal Hypothesis

    PubMed Central

    Sota, Teiji; Belton, Peter; Tseng, Michelle; Yong, Hoi Sen; Mogi, Motoyoshi

    2015-01-01

    The coastal mosquito Aedes togoi occurs more or less continuously from subarctic to subtropic zones along the coasts of the Japanese islands and the East Asian mainland. It occurs also in tropical Southeast Asia and the North American Pacific coast, and the populations there are thought to have been introduced from Japan by ship. To test this hypothesis, the genetic divergence among geographic populations of A. togoi was studied using one mitochondrial and three nuclear gene sequences. We detected 71 mitochondrial haplotypes forming four lineages, with high nucleotide diversity around temperate Japan and declining towards peripheral ranges. The major lineage (L1) comprised 57 haplotypes from temperate and subarctic zones in Japan and Southeast Asia including southern China and Taiwan. Two other lineages were found from subtropical islands (L3) and a subarctic area (L4) of Japan. The Canadian population showed one unique haplotype (L2) diverged from the other lineages. In the combined nuclear gene tree, individuals with mitochondrial L4 haplotypes diverged from those with the other mitochondrial haplotypes L1—L3; although individuals with L1—L3 haplotypes showed shallow divergences in the nuclear gene sequences, individuals from Southeast Asia and Canada each formed a monophyletic group. Overall, the genetic composition of the Southeast Asian populations was closely related to that of temperate Japanese populations, suggesting recent gene flow between these regions. The Canadian population might have originated from anthropogenic introduction from somewhere in Asia, but the possibility that it could have spread across the Beringian land bridge cannot be ruled out. PMID:26107619

  7. Exposure of trees to drought-induced die-off is defined by a common climatic threshold across different vegetation types.

    PubMed

    Mitchell, Patrick J; O'Grady, Anthony P; Hayes, Keith R; Pinkard, Elizabeth A

    2014-04-01

    Increases in drought and temperature stress in forest and woodland ecosystems are thought to be responsible for the rise in episodic mortality events observed globally. However, key climatic drivers common to mortality events and the impacts of future extreme droughts on tree survival have not been evaluated. Here, we characterize climatic drivers associated with documented tree die-off events across Australia using standardized climatic indices to represent the key dimensions of drought stress for a range of vegetation types. We identify a common probabilistic threshold associated with an increased risk of die-off across all the sites that we examined. We show that observed die-off events occur when water deficits and maximum temperatures are high and exist outside 98% of the observed range in drought intensity; this threshold was evident at all sites regardless of vegetation type and climate. The observed die-off events also coincided with at least one heat wave (three consecutive days above the 90th percentile for maximum temperature), emphasizing a pivotal role of heat stress in amplifying tree die-off and mortality processes. The joint drought intensity and maximum temperature distributions were modeled for each site to describe the co-occurrence of both hot and dry conditions and evaluate future shifts in climatic thresholds associated with the die-off events. Under a relatively dry and moderate warming scenario, the frequency of droughts capable of inducing significant tree die-off across Australia could increase from 1 in 24 years to 1 in 15 years by 2050, accompanied by a doubling in the occurrence of associated heat waves. By defining commonalities in drought conditions capable of inducing tree die-off, we show a strong interactive effect of water and high temperature stress and provide a consistent approach for assessing changes in the exposure of ecosystems to extreme drought events.

  8. Exposure of trees to drought-induced die-off is defined by a common climatic threshold across different vegetation types

    PubMed Central

    Mitchell, Patrick J; O'Grady, Anthony P; Hayes, Keith R; Pinkard, Elizabeth A

    2014-01-01

    Increases in drought and temperature stress in forest and woodland ecosystems are thought to be responsible for the rise in episodic mortality events observed globally. However, key climatic drivers common to mortality events and the impacts of future extreme droughts on tree survival have not been evaluated. Here, we characterize climatic drivers associated with documented tree die-off events across Australia using standardized climatic indices to represent the key dimensions of drought stress for a range of vegetation types. We identify a common probabilistic threshold associated with an increased risk of die-off across all the sites that we examined. We show that observed die-off events occur when water deficits and maximum temperatures are high and exist outside 98% of the observed range in drought intensity; this threshold was evident at all sites regardless of vegetation type and climate. The observed die-off events also coincided with at least one heat wave (three consecutive days above the 90th percentile for maximum temperature), emphasizing a pivotal role of heat stress in amplifying tree die-off and mortality processes. The joint drought intensity and maximum temperature distributions were modeled for each site to describe the co-occurrence of both hot and dry conditions and evaluate future shifts in climatic thresholds associated with the die-off events. Under a relatively dry and moderate warming scenario, the frequency of droughts capable of inducing significant tree die-off across Australia could increase from 1 in 24 years to 1 in 15 years by 2050, accompanied by a doubling in the occurrence of associated heat waves. By defining commonalities in drought conditions capable of inducing tree die-off, we show a strong interactive effect of water and high temperature stress and provide a consistent approach for assessing changes in the exposure of ecosystems to extreme drought events. PMID:24772285

  9. Balanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes

    USGS Publications Warehouse

    Rosencranz, Jordan A.; Ganju, Neil K.; Ambrose, Richard F.; Brosnahan, Sandra M.; Dickhudt, Patrick J.; Guntenspergen, Glenn R.; MacDonald, Glen M.; Takekawa, John Y.; Thorne, Karen M.

    2016-01-01

    Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are potentially important for marsh stability. We calculated tidal creek sediment fluxes within a highly modified, sediment-starved, 1.5-km2 salt marsh (Seal Beach) and a less modified 1-km2marsh (Mugu) with fluvial sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12,000 and 8800 kg in a western and eastern channel. Western channel storm imports offset 8700 kg exported during 2 months of dry weather, while eastern channel storm imports augmented 9200 kg imported during dry weather. During the storm at Mugu, suspended sediment concentrations on the marsh plain increased by a factor of four; accretion was 1–2 mm near creek levees. An exceptionally high tide sequence yielded 4.4 g/s mean sediment flux, importing 1700 kg: 20 % of Mugu’s dry weather fluxes. Overall, low sediment fluxes were observed, suggesting that these salt marshes are geomorphically stable during dry weather conditions. Results suggest storms and high lunar tides may play large roles, importing sediment and maintaining dry weather sediment flux balances for southern California salt marshes. However, under future climate change and sea level rise scenarios, results suggest that balanced sediment fluxes lead to marsh elevational instability based on estimated mineral sediment deficits.

  10. Climatically-Active Gases in the Eastern Boundary Upwelling and Oxygen Minimum Zone (OMZ) Systems

    NASA Astrophysics Data System (ADS)

    Garbe, C.; Garçon, V.; Butz, A.; Yahia, H.; Sudre, J.; Illig, S.; Dewitte, B.; Paulmier, A.; Dadou, I.

    2012-04-01

    The EBUS (Eastern Boundary Upwelling Systems) and OMZs (Oxygen Minimum Zone) contribute very significantly to the gas exchange between the ocean and the atmosphere, notably with respect to the greenhouse gases (hereafter GHG). From in-situ ocean measurements, the uncertainty of the net global ocean-atmosphere CO2 fluxes is between 20 and 30%, and could be much higher in the EBUS-OMZ. Off Peru, very few in-situ data are available presently, which justifies alternative approaches for assessing these fluxes. GHG air-sea fluxes determination can be inferred from inverse modeling applied to Vertical Column Densities (VCDs) from GOSAT, using state of the art modeling, at low spatial resolution. For accurately linking sources of GHGs to EBUS and OMZs, the resolution of the source regions needs to be increased. This task develops on new non-linear and multiscale processing methods for complex signals to infer a higher spatial resolution mapping of the fluxes and the associated sinks and sources between the atmosphere and the ocean. The use of coupled satellite data (e.g. SST and/or Ocean colour) that carry turbulence information associated to ocean dynamics is taken into account at unprecedented detail level to incorporate turbulence effects in the evaluation of the air-sea fluxes. We will present a framework as described above for determining sources and sinks of GHG from satellite remote sensing with the Peru OMZ as a test bed.

  11. Development Of Regional Climate Mitigation Baseline For A DominantAgro-Ecological Zone Of Karnataka, India

    SciTech Connect

    Sudha, P.; Shubhashree, D.; Khan, H.; Hedge, G.T.; Murthy, I.K.; Shreedhara, V.; Ravindranath, N.H.

    2007-06-01

    Setting a baseline for carbon stock changes in forest andland use sector mitigation projects is an essential step for assessingadditionality of the project. There are two approaches for settingbaselines namely, project-specific and regional baseline. This paperpresents the methodology adopted for estimating the land available formitigation, for developing a regional baseline, transaction cost involvedand a comparison of project-specific and regional baseline. The studyshowed that it is possible to estimate the potential land and itssuitability for afforestation and reforestation mitigation projects,using existing maps and data, in the dry zone of Karnataka, southernIndia. The study adopted a three-step approach for developing a regionalbaseline, namely: i) identification of likely baseline options for landuse, ii) estimation of baseline rates of land-use change, and iii)quantification of baseline carbon profile over time. The analysis showedthat carbon stock estimates made for wastelands and fallow lands forproject-specific as well as the regional baseline are comparable. Theratio of wasteland Carbon stocks of a project to regional baseline is1.02, and that of fallow lands in the project to regional baseline is0.97. The cost of conducting field studies for determination of regionalbaseline is about a quarter of the cost of developing a project-specificbaseline on a per hectare basis. The study has shown the reliability,feasibility and cost-effectiveness of adopting regional baseline forforestry sectormitigation projects.

  12. Climate Sensitivity Functions and Ecosystem Dynamics Across a Grassland to Shrubland Transition Zone

    NASA Astrophysics Data System (ADS)

    Collins, S. L.; Rudgers, J.; Muldavin, E.; Moore, D. I.

    2016-12-01

    A strong relationship between aboveground net primary production (NPP) and mean annual precipitation (MAP) has been documented along spatial gradients in grasslands worldwide, impling that MAP controls NPP spatially. Yet, the relationship between annual precipitation (PPT) and NPP within a site over time is generally weak. Thus, factors in addition to PPT must regulate the temporal dynamics of NPP. In many regions, climate models predict higher mean annual temperature (MAT) and precipitation variability in the future. Higher MAT may interact non-linearly with changes in PPT amount and variability to alter the temporal dynamics of NPP. Indices such as the Standardized Precipitation Evaporation Index (SPEI) explicitly integrate MAT and PPT. We used non-linear mixed effects models on 17 years of data from desert grassland and shrubland communities in central New Mexico (Sevilleta) to model the non-linear responses of NPP to temperature and precipitation variability, and how these responses might drive grassland dynamics and shrub encroachment. Our study system spans ecotones from blue grama to black grama grassland, and black grama grassland to creosote shrubland. Since 1989, SPEI has declined (r=0.38) at Sevilleta while variance in SPEI has increased (r=0.50). Over time, black grama has increased in abundance relative to blue grama, and creosote has encroached into black grama grassland, trends consistent with higher aridity. We found significant non-linear and opposing responses of blue and black grama grassland to interannual variability in PPT and MAT. NPP of black grama grassland benefits from increased variance under low SPEI (p=0.019) whereas blue grama NPP declined under increased variance at low SPEI (p=0.0001). That is, NPP of black grama grassland benefited from increased variability during warmer years and did poorly under high variance in cooler years. The opposite was true for blue grama. Creosote shrubland responded linearly to variability and changes

  13. Persistence and dissipation kinetics of deltamethrin on chili in different agro-climatic zones of India.

    PubMed

    Pandher, Suneet; Sahoo, S K; Battu, R S; Singh, Balwinder; Saiyad, M S; Patel, A R; Shah, P G; Reddy, C Narendra; Reddy, D Jagdishwar; Reddy, K Narasimha; Rao, Ch Sreenivasa; Banerjee, Tirthankar; Banerjee, Devottam; Hudait, Ramkumar; Banerjee, Hemanta; Tripathy, Vandana; Sharma, K K

    2012-05-01

    Multi-location supervised field trials were conducted at four different agro climatic locations in India to evaluate the dissipation pattern of deltamethrin on chili. Deltamethrin 10 EC was applied on chili @17.5 and 35 g a.i. ha(-1), samples of green chili were drawn at different time intervals and that of red chili and soil at harvest time and quantified by gas liquid chromatography equipped with electron capture detector. The identity of residues were confirmed by Gas Chromatograph-Mass Spectrophotometer in selective ion monitoring mode in mass range 181, 253 m/z. Limit of quantification of the method was found to be 0.01 mg kg(-1). Half-life of deltamethrin at application rate of 17.5 g a.i. ha(-1) varied from 0.36 to 1.99 days and at double the application rate was found to range from 0.38 to 2.06 days. Residues of deltamethrin were found below its determination limit of 0.01 mg kg(-1) in red chili and soil. On the basis of the data generated, Deltamethrin 10 EC has been registered for use on chili in India and its Maximum Residue Limit has been fixed as 0.05 μg/g.

  14. Characteristics and source apportionment of organic matter in PM(2.5) from cities in different climatic zones of China

    NASA Astrophysics Data System (ADS)

    Feng, Jialiang

    For the first time, the dependency of the characteristics of organic matter in PM2.5 on geographical and climatic zones in three metropolitan cities of China was studied. Seasonal samples were collected at suburban and urban sites in Beijing, Shanghai and Guangzhou in 2002 and 2003. To further support the above study, seasonal samples were also collected at Changdao Island, a remote island, in Bohai Sea/Yellow Sea. Concentrations of organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), and solvent-extractable organic compounds (SEOC) were analyzed. The characteristics of the n-alkanes, polycyclic aromatic hydrocarbons, n-fatty acids, n-alkanols and molecular markers such as triterpanes were determined and used for source identification. Source apportionment was complemented by Chemical Mass Balance (CMB) modeling using the measured organic species as tracers. The impact of wind speed and wind direction on air quality was studied by back trajectory calculations and analysis. In general, traffic emissions were the largest contributors of OC followed by coal burning, kitchen emissions, vegetative detritus and biomass burning. However, in the space-heating season in Northern China, coal burning was the most important contributor of OC in the suburban areas of Beijing and at Changdao. Beijing had the highest concentration of organic aerosol followed by Guangzhou and Shanghai, while seasonal variation was in reverse order. Dispersion conditions determined by local topographies and meteorology were responsible for this trend. Contrary to common understanding, pollutant concentrations at the suburban sites were higher than the urban sites in all three cities. The main reason was the rapid urbanization of the suburban areas in the immediate vicinity of urban centers since China opened up for economic development, in addition, large numbers of manufacturing plants were relocated from the cities to the countryside in an attempt to clean up the urban

  15. [Response of cotton seeding date to climate warming in Northern Slope Economic Zone of Tianshan Mountain, China].

    PubMed

    Zhi, Juan; Zhang, Shan-qing; Xu, Wen-xiu; Tian, Yan-jun; Zhang, Na; Su, Li-li

    2015-07-01

    Based on the meteorological date acquired from 11 meteorological stations in Northern Slope Economic Zone of Tianshan Mountain during 1971-2010 and by using the methods of linear regression, t-test technique and IDW interpolation, this paper analyzed the spatial distribution of each ten-day average temperature from late March to late April and beginning date of ≥ 12 °C to understand the effect of climate change on the cotton seeding date. Results showed that each ten-day average temperature from late March to late April increased by 0. 8, 0. 5, 0. 1 and 0. 5 °C . (10 a)-1, but the beginning date of ≥12 °C advanced by 0.5 d . (10 a)-1 during 1971-2010. All meteorological elements in this research ascended abruptly in the 1990s. The abrupt climate change made each ten-day average temperature increasing by 2.5, 1.9, 1.1 and 1.5 °C, to 7.2, 10.0, 13.2 and 15.6 °C, respectively from late March to late April. The high values of each ten-day average temperature from late March to late April expanded the scope of main cotton producing areas in Northern Slope Economic Zone of Tianshan Mountain, such as Wusu, Sawan and Manasi, and the low values were observed in Urmuqi. The spatial distribution of the beginning day of ≥12 °C was significant different in different regions. During this study period, the early beginning dates of ≥ 12 °C expanded the scope of Jinghe and Manasi as cotton producing areas, and the late beginning dates of ≥ 12 °C narrowed to areas around Urumqi. With the advance of the beginning day of ≥ 12 °C, the seeding date of cotton could start from 22nd to 28th April in most of the counties, and mulch cover could bring forward the suitable sowing date to 15th through 21st April.

  16. Climate, Demography, and Zoogeography Predict Introgression Thresholds in Salmonid Hybrid Zones in Rocky Mountain Streams.

    PubMed

    Young, Michael K; Isaak, Daniel J; McKelvey, Kevin S; Wilcox, Taylor M; Bingham, Daniel M; Pilgrim, Kristine L; Carim, Kellie J; Campbell, Matthew R; Corsi, Matthew P; Horan, Dona L; Nagel, David E; Schwartz, Michael K

    2016-01-01

    Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78-0.86; classification success, 72-82%; 10-fold cross validation, 70-82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer habitats and to recent sources of rainbow trout propagules, presence within the historical range of rainbow trout, and locations further east. Assuming that water temperatures will continue to rise in response to climate change and that levels of introgression outside the historical range of rainbow trout will equilibrate with those inside that range, we applied six scenarios across a 55,234-km stream network that forecast 9.5-74.7% declines in the amount of habitat occupied by westslope cutthroat trout populations of conservation value, but not the wholesale loss of such populations. We conclude that introgression between these taxa is predictably related to environmental conditions, many of which can be manipulated to foster largely genetically intact populations of westslope cutthroat trout and help managers prioritize conservation activities.

  17. Balanced Sediment Fluxes in Southern California's Mediterranean-climate Zone Salt Marshes

    NASA Astrophysics Data System (ADS)

    Rosencranz, J. A.; Dickhudt, P.; Ganju, N. K.; Thorne, K.; Takekawa, J.; Ambrose, R. F.; Guntenspergen, G. R.; Brosnahan, S.; MacDonald, G. M.

    2015-12-01

    Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many southern California, USA salt marshes import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are also potentially important for marsh stability. We calculated tidal creek sediment fluxes within a sediment starved 1.5 km2 salt marsh (Seal Beach) and a less modified 1 km2 marsh (Mugu) with a watershed sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12000 and 8800 kg in a western channel. This offset 8700 kg export during two months of dry weather, while landward net fluxes in the eastern channel accounted for 33% of the import. During the storm, suspended sediment concentrations on the marsh plain increased by a factor of four; accretion was 1-2 mm near creek levees. An exceptionally high tide sequence at Mugu yielded 4.4 g/s mean sediment flux, importing 1700 kg, accounting for 20% of dry weather fluxes. Overall, low sediment fluxes were observed, suggesting that these salt marshes are currently geomorphically stable. Our results suggest that storms and exceptionally high lunar tides may play large roles, importing sediment and maintaining dry weather sediment flux balances for southern California salt marshes. However, under future climate change and sea-level rise scenarios, results suggest that balanced sediment fluxes may lead to marsh elevational instability, based on estimated mineral sediment deficits.

  18. Climate, Demography, and Zoogeography Predict Introgression Thresholds in Salmonid Hybrid Zones in Rocky Mountain Streams

    PubMed Central

    Young, Michael K.; Isaak, Daniel J.; McKelvey, Kevin S.; Wilcox, Taylor M.; Pilgrim, Kristine L.; Carim, Kellie J.; Campbell, Matthew R.; Corsi, Matthew P.; Horan, Dona L.; Nagel, David E.; Schwartz, Michael K.

    2016-01-01

    Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78–0.86; classification success, 72–82%; 10-fold cross validation, 70–82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer habitats and to recent sources of rainbow trout propagules, presence within the historical range of rainbow trout, and locations further east. Assuming that water temperatures will continue to rise in response to climate change and that levels of introgression outside the historical range of rainbow trout will equilibrate with those inside that range, we applied six scenarios across a 55,234-km stream network that forecast 9.5–74.7% declines in the amount of habitat occupied by westslope cutthroat trout populations of conservation value, but not the wholesale loss of such populations. We conclude that introgression between these taxa is predictably related to environmental conditions, many of which can be manipulated to foster largely genetically intact populations of westslope cutthroat trout and help managers prioritize conservation activities. PMID:27828980

  19. Modeled Interactive Effects of Precipitation, temperature, and [CO2] on Ecosystem Carbon and Water Dynamics in Different Climatic Zones

    SciTech Connect

    Luo, Yiqi; Gerten, Dieter; Le Maire, Guerric; Parton, William; Weng, Ensheng; Zhou, Xuhuui; Keough, Cindy; Beier, Claus; Ciais, Philippe; Cramer, Wolfgang; Dukes, Jeff; Emmett, Bridget; Hanson, Paul J; Knapp, Alan; Linder, Sune; Nepstad, Daniel; Rustad, Lindsey

    2008-01-01

    Interactive effects of multiple global change factors on ecosystem processes are complex. It is relatively expensive to explore those interactions in manipulative experiments. We conducted a modeling analysis to identify potentially important interactions and to stimulate hypothesis formulation for experimental research. Four models were used to quantify interactive effects of climate warming (T), altered precipitation amounts [doubled (DP) and halved (HP)] and seasonality (SP, moving precipitation in July and August to January and February to create summer drought), and elevated [CO2] (C) on net primary production (NPP), heterotrophic respiration (Rh), net ecosystem production (NEP), transpiration, and runoff.We examined those responses in seven ecosystems, including forests, grasslands, and heathlands in different climate zones. The modeling analysis showed that none of the threeway interactions among T, C, and altered precipitation was substantial for either carbon or water processes, nor consistent among the seven ecosystems. However, two-way interactive effects on NPP, Rh, and NEP were generally positive (i.e. amplification of one factor s effect by the other factor) between T and C or between T and DP. A negative interaction (i.e. depression of one factor s effect by the other factor) occurred for simulated NPP between T and HP. The interactive effects on runoff were positive between T and HP. Four pairs of two-way interactive effects on plant transpiration were positive and two pairs negative. In addition, wet sites generally had smaller relative changes in NPP, Rh, runoff, and transpiration but larger absolute changes in NEP than dry sites in response to the treatments. The modeling results suggest new hypotheses to be tested in multifactor global change experiments. Likewise, more experimental evidence is needed for the further improvement of ecosystem models in order to adequately simulate complex interactive processes.

  20. Plants Assemble Species Specific Bacterial Communities from Common Core Taxa in Three Arcto-Alpine Climate Zones

    PubMed Central

    Kumar, Manoj; Brader, Günter; Sessitsch, Angela; Mäki, Anita; van Elsas, Jan D.; Nissinen, Riitta

    2017-01-01

    Evidence for the pivotal role of plant-associated bacteria to plant health and productivity has accumulated rapidly in the last years. However, key questions related to what drives plant bacteriomes remain unanswered, among which is the impact of climate zones on plant-associated microbiota. This is particularly true for wild plants in arcto-alpine biomes. Here, we hypothesized that the bacterial communities associated with pioneer plants in these regions have major roles in plant health support, and this is reflected in the formation of climate and host plant specific endophytic communities. We thus compared the bacteriomes associated with the native perennial plants Oxyria digyna and Saxifraga oppositifolia in three arcto-alpine regions (alpine, low Arctic and high Arctic) with those in the corresponding bulk soils. As expected, the bulk soil bacterial communities in the three regions were significantly different. The relative abundances of Proteobacteria decreased progressively from the alpine to the high-arctic soils, whereas those of Actinobacteria increased. The candidate division AD3 and Acidobacteria abounded in the low Arctic soils. Furthermore, plant species and geographic region were the major determinants of the structures of the endophere communities. The plants in the alpine region had higher relative abundances of Proteobacteria, while plants from the low- and high-arctic regions were dominated by Firmicutes. A highly-conserved shared set of ubiquitous bacterial taxa (core bacteriome) was found to occur in the two plant species. Burkholderiales, Actinomycetales and Rhizobiales were the main taxa in this core, and they were also the main contributors to the differences in the endosphere bacterial community structures across compartments as well as regions. We postulate that the composition of this core is driven by selection by the two plants. PMID:28174556

  1. Permafrost and organic layer interactions over a climate gradient in a discontinuous permafrost zone

    SciTech Connect

    Johnson, Kristopher D; Harden, Jennifer; McGuire, A. David; Clark, Mark; Yuan, Fengming; Finley, Andrew

    2013-01-01

    Permafrost is tightly coupled to the organic layer, an interaction that mediates permafrost degradation in response to regional warming. We analyzed changes in permafrost occurrence (PF) and organic layer thickness (OLT) in more than 3000 soil pedons across a mean annual temperature (MAT) gradient. Cause and effect relationships between PF, OLT, and other topographic factors were investigated using structural equation modeling in a multi-group analysis. Groups were defined by slope, soil texture type, and shallow v. deep organic layers. Permafrost probability sharply increased by 0.32 for every 10-cm OLT increase in shallow OLT soils (OLTs) due to an insulation effect, but PF decreased in deep OLT soils (OLTd) by 0.06 for every 10-cm increase. As temperature warmed, sandy soils varied little in PF or OLT, but PF in loamy and sandy soils decreased substantially. The change in OLT was more heterogeneous across soil types in some there was no change while in others OLTs soils thinned and/or OLTd soils thickened as temperature warmed. Furthermore, the rate of thickening with warming for OLTd soils was on average almost 4 times greater than the rate of thinning for OLTs soils across all soil types. If soils follow a trajectory of warming that mimics the spatial gradients found today, then heterogeneities of permafrost degradation and organic layer thinning and thickening should be considered in the regional carbon balance.

  2. Generalized models for estimation of diffuse solar radiation based on clearness index and sunshine duration in India: Applicability under different climatic zones

    NASA Astrophysics Data System (ADS)

    Jamil, Basharat; Siddiqui, Abid T.

    2017-05-01

    Generalized models for assessment of monthly average diffuse solar radiation over India were established using long-term solar radiation data available for 15 years (1986-2000) obtained from Indian Meteorological Department (IMD), Pune. Regression analysis was employed to correlate the diffuse fraction (K̅d) with clearness index (K̅t) and relative sunshine period (S̅/S̅o) together. Seven new models (with two input variables i.e. global solar radiation and relative sunshine period) were developed using data of the measurement sites. Well-established models from literature were also compared with the proposed models. Statistical tests used to evaluate the accuracy of models were mean bias error, root mean square error, mean percentage error, coefficient of determination, t-statistics and normalized median absolute deviation. Global performance indicator (GPI) was used to rank the models. Further, the empirical models were applied on the five representative locations under diverse climatic zones (i.e. Hot & Dry, Warm & Humid, Temperate, Cold and Composite climates) prescribed by the Energy Conservation Building Code (ECBC) for India. Proposed models were also compared within each climatic zone and best model was recommended. Developed models were found to have good performance on collective data as well as under each climatic zone individually.

  3. Examining the Role of Local Climate Zones in Urban Heat Island Assessment Using Remotely-Sensed Data

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

    More than half of the world population resides in urban areas where the urban heat island (UHI) effect enhances heat-related hazards. To mitigate the impacts of rising temperatures, it is necessary to develop tools to help public administrators formulate strategies to reduce heat exposure, increase access to cooling, and modify building design. We used Google Earth Engine's Landsat archive to classify local climate zones (LCZ) that consist of ten urban and seven non-urban classifications of land cover. To examine the influence of urban morphology on the surface energy balance (SEB) in high-density, medium-density, and low-density urban regions over one annual cycle, we used Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) and normalized difference vegetation index (NDVI) products. We used the triangle method to examine variability in energy balance partitioning in relation to urban density. As urban density decreases, the variation of evapotranspiration increases. These results indicate 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.

  4. The lag effects and vulnerabilities of temperature effects on cardiovascular disease mortality in a subtropical climate zone in China.

    PubMed

    Huang, Jixia; Wang, Jinfeng; Yu, Weiwei

    2014-04-11

    This research quantifies the lag effects and vulnerabilities of temperature effects on cardiovascular disease in Changsha--a subtropical climate zone of China. A Poisson regression model within a distributed lag nonlinear models framework was used to examine the lag effects of cold- and heat-related CVD mortality. The lag effect for heat-related CVD mortality was just 0-3 days. In contrast, we observed a statistically significant association with 10-25 lag days for cold-related CVD mortality. Low temperatures with 0-2 lag days increased the mortality risk for those ≥65 years and females. For all ages, the cumulative effects of cold-related CVD mortality was 6.6% (95% CI: 5.2%-8.2%) for 30 lag days while that of heat-related CVD mortality was 4.9% (95% CI: 2.0%-7.9%) for 3 lag days. We found that in Changsha city, the lag effect of hot temperatures is short while the lag effect of cold temperatures is long. Females and older people were more sensitive to extreme hot and cold temperatures than males and younger people.

  5. Meteorologic factors and temporal variations of cardiac mortality in an urban setting in a desert climatic zone.

    PubMed

    Cech, I; Smolensky, M; Lane, R; Halevy, B; Samueloff, S

    1977-05-01

    The aim of this investigation was to study, by use of the unbiased and rigorous techniques of lagged cross-covariance and spectral analyses, the associations between daily cardiac mortality and weather conditions in Beersheba, an urban center situated in a hot and dry climatic zone. The results of the analyses point to the existence of seasonal differences in mortality, with a peak in winter. Of greater interest is the statistical documentation of temporal associations between short-term increases in daily mortality and certain weather situations corresponding to the transitional periods of turbulent atmosphere with below normal air temperatures, strong gusty winds and a drop in relative humidity, i.e., conditions accompanying the intrusion of a winter cold wave. The crests in short-term mortality occurred most often within a week of the intrusion of the cold air masses. No consistent cross association was found between high summer temperatures and mortality. The results of this investigation are discussed in the light of those previously reported for Tel Aviv (a coastal city) and Jerusalem (a city situated at a high altitude).

  6. Permafrost and organic layer interactions over a climate gradient in a discontinuous permafrost zone

    USGS Publications Warehouse

    Johnson, Kristofer D.; Harden, Jennifer W.; McGuire, A. David; Clark, Mark; Yuan, Fengming; Finley, Andrew O.

    2013-01-01

    Permafrost is tightly coupled to the organic soil layer, an interaction that mediates permafrost degradation in response to regional warming. We analyzed changes in permafrost occurrence and organic layer thickness (OLT) using more than 3000 soil pedons across a mean annual temperature (MAT) gradient. Cause and effect relationships between permafrost probability (PF), OLT, and other topographic factors were investigated using structural equation modeling in a multi-group analysis. Groups were defined by slope, soil texture type, and shallow (<28 cm) versus deep organic (≥28 cm) layers. The probability of observing permafrost sharply increased by 0.32 for every 10-cm OLT increase in shallow OLT soils (OLTs) due to an insulation effect, but PF decreased in deep OLT soils (OLTd) by 0.06 for every 10-cm increase. Across the MAT gradient, PF in sandy soils varied little, but PF in loamy and silty soils decreased substantially from cooler to warmer temperatures. The change in OLT was more heterogeneous across soil texture types—in some there was no change while in others OLTs soils thinned and/or OLTd soils thickened at warmer locations. Furthermore, when soil organic carbon was estimated using a relationship with thickness, the average increase in carbon in OLTd soils was almost four times greater compared to the average decrease in carbon in OLTs soils across all soil types. If soils follow a trajectory of warming that mimics the spatial gradients found today, then heterogeneities of permafrost degradation and organic layer thinning and thickening should be considered in the regional carbon balance.

  7. Dynamic Asia: Coupling of climate, tectonics, rivers, and people defines risk and opportunity for the world's largest human populations

    NASA Astrophysics Data System (ADS)

    Goodbred, S. L., Jr.; Steckler, M. S.; Gilligan, J. M.; Ackerly, B.; Ayers, J. C.; Wilson, C.; Small, C.; Seeber, L.

    2014-12-01

    Coupling between the Himalayan-Tibetan uplift and intense Asian monsoon yields tremendous regional runoff and sediment supply. This vigorous mass-transfer system sustains 7 of the world's 10 largest riverine sediment loads, which in turn have constructed vast, fertile fluvial-deltaic lowlands. These environments across south and east Asia host about 1/3 of all people on Earth. Such large and dense populations have flourished amidst the region's generally abundant water supplies, fisheries, and agricultural production. Yet the same environmental attributes that are so rich in resources also define a uniquely dynamic region, where rates of change are rapid and punctuated by frequent, intense events. Indeed, 8 of the world's 10 deadliest natural disasters have occurred in this region, involving a combination of earthquakes, tropical cyclones, river floods, and tsunamis. Other stresses that regularly impact the region include periods of monsoon collapse and drought, widespread arsenic contamination of groundwater, relative sea-level rise and coastal inundation, and groundwater salinization. Thus the communities of this region persistently face the challenge of balancing the carrying capacity of a resource-rich environment with its associated hazards and challenges. One important concept that has become increasingly more apparent is the connection within watersheds that transmits local effects both upstream and downstream within the system. Here we emphasize two additional points that we believe are essential in developing plausible strategies for sustaining health, resilience, and stability of the region. First, problems related to the natural environment are closely coupled with human activities and our concurrent responses to environmental change. Thus resulting issues are complex and multifaceted in ways that require natural scientists to better engage with researchers in the humanities and social sciences. Second, despite similar risks affecting many millions of

  8. Longleaf pine site zones

    Treesearch

    Phillip J. Craul; John S. Kush; William D. Boyer

    2005-01-01

    The authors delineate six major climatic areas of the longleaf pine (Pinus palustris Mill.) region. They subdivide these areas into 21 site zones, each of which is deemed homogenous with respect to climate, physiography, and soils. The site zones are mapped and their climate, physiography, and soils described. The authors recommend that plantings of...

  9. Climates

    Treesearch

    John R. Jones; Norbert V. DeByle

    1985-01-01

    The broad range of aspen in North America is evidence of its equally broad tolerance of wide variations in climate (Fowells 1965). Given open space for establishment and not too severe competition from other plants, aspen can survive from timberline on the tundra's edge to very warm temperate climates, and from the wet maritime climates of the coasts to very...

  10. Initial generation of sand across climate zones of the Mojave, Sierra Nevada, and Klamath Batholiths in California, U.S.A.

    NASA Astrophysics Data System (ADS)

    Hessler, Angela M.; Lowe, Donald R.

    2017-03-01

    The generation of modern, plutoniclastic sediment across California varies with climate, resulting in significant mineralogical and geochemical differences between parent rock, weathering profile material, and low-order stream sand. With average precipitation of 15 cm/yr in the arid zones and 120 cm/yr in the temperate zones, feldspar is relatively decreased in stream sand (compared to parent rock) by < 2% and 20%, respectively. Potassium feldspar is more resistant to weathering than plagioclase but is less stable than quartz in temperate climates. Hornblende and biotite are more easily weathered in temperate than arid climates, although their occurrence in medium-grained stream sands is affected by hydraulic sorting and comminution during transport. Temperate-climate sands have lower concentrations of CaO and Na2O compared to K2O and Al2O3, reflective of the expected faster loss of plagioclase than potassium feldspar during weathering. With the exception of biotite, the mineralogy of medium-grained stream sand reflects that of medium-grained weathering profile material in both climates, confirming the findings from constant-climate case studies that the composition of proximal sand is largely achieved within weathering profiles and during initial erosion. We encourage continued attention to climate as a control on sand composition in provenance and paleoclimate studies, where a moderate precipitation shift is capable of producing a significant loss of feldspar. The differential response of common minerals to chemical weathering should be considered for studies and modeling related to bedrock erodibility, sediment supply, and landscape evolution.

  11. Seasonal prevalence of gastrointestinal helminths in sheep and goats of middle agro-climatic zone of Jammu province.

    PubMed

    Khajuria, J K; Katoch, R; Yadav, Anish; Godara, R; Gupta, S K; Singh, Ajitpal

    2013-04-01

    A total of 1920 faecal samples of sheep (960) and goats (960) of stationary flocks of the middle agro-climatic zone of Jammu province were examined, out of which 67.24 % animals were positive for helminthic infections. The different nematodes observed were strongyles (50.1 %), trichurids (12.1 %) and Strongyloides spp. (4.2 %). Trematode ova recorded were of amphistomes (8.3 %), Fasciola spp. (8.2 %) and Dicrocoelium spp. (5.4 %). No significant difference was observed between the infection level in sheep (68.54 %) and goats (65.94 %) which could be attributed to mixed grazing and sharing of pastures/sheds. Significantly (p < 0.05) higher infection was observed in monsoon as compared to winter. Strongyles were predominant during all the seasons, but significantly (p < 0.05) higher infection was observed in monsoon as compared to winter. Coproculture studies revealed that Haemonchus contortus (61.18 %) predominated during all the seasons, followed by Trichostrongylus spp. (13.67 %), Ostertagia spp. (12.17 %), Strongyloides spp. (4.14 %), Oesophagostomum spp. (3.84 %) and Bunostomum spp. (3.83 %). Eggs per gram of faeces (EPG) were the highest (sheep 1883.33 ± 117.6 and goats 1800 ± 110.21) during monsoon and the lowest during winter (sheep 640 ± 41.29 and goats 556.67 ± 33.01). Two peaks of EPG (the first in May and the second in August) were recorded during the 1 year study period. Infection was significantly (p < 0.05) higher in young (73.22 %) as compared to adults (61.25 %). Females showed a higher infection (73.33 %) as compared to males (61.14 %). The effect of prevailing agro-climatic conditions on the prevalence of gastrointestinal helminths has been discussed.

  12. Thermal comfort in naturally ventilated and air-conditioned buildings in humid subtropical climate zone in China.

    PubMed

    Yang, Wei; Zhang, Guoqiang

    2008-05-01

    A thermal comfort field study has been carried out in five cities in the humid subtropical climate zone in China. The survey was performed in naturally ventilated and air-conditioned buildings during the summer season in 2006. There were 229 occupants from 111 buildings who participated in this study and 229 questionnaire responses were collected. Thermal acceptability assessment reveals that the indoor environment in naturally ventilated buildings could not meet the 80% acceptability criteria prescribed by ASHRAE Standard 55, and people tended to feel more comfortable in air-conditioned buildings with the air-conditioned occupants voting with higher acceptability (89%) than the naturally ventilated occupants (58%). The neutral temperatures in naturally ventilated and air-conditioned buildings were 28.3 degrees C and 27.7 degrees C, respectively. The range of accepted temperature in naturally ventilated buildings (25.0-31.6 degrees C) was wider than that in air-conditioned buildings (25.1-30.3 degrees C), which suggests that occupants in naturally ventilated buildings seemed to be more tolerant of higher temperatures. Preferred temperatures were 27.9 degrees C and 27.3 degrees C in naturally ventilated and air-conditioned buildings, respectively, both of which were 0.4 degrees C cooler than neutral temperatures. This result suggests that people of hot climates may use words like "slightly cool" to describe their preferred thermal state. The relationship between draught sensation and indoor air velocity at different temperature ranges indicates that indoor air velocity had a significant influence over the occupants' comfort sensation, and air velocities required by occupants increased with the increasing of operative temperatures. Thus, an effective way of natural ventilation which can create the preferred higher air movement is called for. Finally, the indoor set-point temperature of 26 degrees C or even higher in air-conditioned buildings was confirmed as making

  13. Thermal comfort in naturally ventilated and air-conditioned buildings in humid subtropical climate zone in China

    NASA Astrophysics Data System (ADS)

    Yang, Wei; Zhang, Guoqiang

    2008-05-01

    A thermal comfort field study has been carried out in five cities in the humid subtropical climate zone in China. The survey was performed in naturally ventilated and air-conditioned buildings during the summer season in 2006. There were 229 occupants from 111 buildings who participated in this study and 229 questionnaire responses were collected. Thermal acceptability assessment reveals that the indoor environment in naturally ventilated buildings could not meet the 80% acceptability criteria prescribed by ASHRAE Standard 55, and people tended to feel more comfortable in air-conditioned buildings with the air-conditioned occupants voting with higher acceptability (89%) than the naturally ventilated occupants (58%). The neutral temperatures in naturally ventilated and air-conditioned buildings were 28.3°C and 27.7°C, respectively. The range of accepted temperature in naturally ventilated buildings (25.0˜31.6°C) was wider than that in air-conditioned buildings (25.1˜30.3°C), which suggests that occupants in naturally ventilated buildings seemed to be more tolerant of higher temperatures. Preferred temperatures were 27.9°C and 27.3°C in naturally ventilated and air-conditioned buildings, respectively, both of which were 0.4°C cooler than neutral temperatures. This result suggests that people of hot climates may use words like “slightly cool” to describe their preferred thermal state. The relationship between draught sensation and indoor air velocity at different temperature ranges indicates that indoor air velocity had a significant influence over the occupants’ comfort sensation, and air velocities required by occupants increased with the increasing of operative temperatures. Thus, an effective way of natural ventilation which can create the preferred higher air movement is called for. Finally, the indoor set-point temperature of 26°C or even higher in air-conditioned buildings was confirmed as making people comfortable, which supports the regulation

  14. Determining the Inner Edge of the Habitable Zone Around M and late K-Stars Using 3-D Climate Models

    NASA Astrophysics Data System (ADS)

    Kopparapu, Ravi; Wolf, Eric T.; Haqq-Misra, Jacob; Jun, Yang; Kasting, James; Mahadevan, Suvrath; Terrien, Ryan

    2015-12-01

    We present preliminary results for the inner edge of the habitable zone (HZ) around M and late K-stars, calculated from state of the art 3-D global climate models, the NCAR Community Atmosphere Model and Flexible Modeling System (FMS) developed by the Geophysical Fluid Dynamics. Both 1-D and 3-D models show that, for a water-rich planet, as the surface temperature increases due to increased stellar radiation, water vapor becomes a significant fraction of the atmosphere. M- and late K-stars have their peak flux in the near-infrared, where water is a strong absorber. Our models have been updated with a new radiation scheme and with H2O absorption coefficients derived from the most recent line-by-line databases (HITRAN2012 and HITEMP2010). These updates will most likely result in moving the inner edge of the HZ around M and late-K stars further away from the star than previous estimates. The initial targets for survey missions such as K2 and the Transiting Exoplanet Survey Satellite (TESS) will likely be planets near the inner edge of the HZ due to the increased signal-to-noise ratio that results from their proximity to their host star. The James Webb Space Telescope (JWST) may be capable of probing the atmospheric composition of terrestrial planets around a nearby M-dwarf. Thus, determining the most accurate inner edge of the HZ around M-dwarf stars is crucial for selecting target candidates for atmospheric characterization and to identify potential biomarkers.

  15. Impacts of recent climate change on dry-land crop water consumption in the northern agro-pastoral transitional zone of China

    NASA Astrophysics Data System (ADS)

    Zhao, Lingyu; Liu, Yaling; Pan, Zhihua; An, Pingli; Pan, Xuebiao; Zhao, Peiyi

    2013-08-01

    Climate change has substantially impacted crop growth and development in the northern agro-pastoral transitional zone. Examination of the response of crop water consumption to climate change may provide a guide for adapting local agricultural production and ecological construction to new realities. The water consumption of three local crops (wheat, naked oats, and potatoes) is examined for Wuchuan County in the northern agro-pastoral transitional zone of China using meteorological data from 1960 to 2007 and soil moisture data from 1983 to 2007. The relationships between climate change and the crop water consumption are discussed. The results show that Wuchuan experienced both a warming trend and a reduction of precipitation between 1960 and 2007. The annual mean surface air temperature increased at a rate of 0.04°C yr-1 and the annual precipitation decreased at a rate of 0.7 mm yr-1. Both trends are particularly pronounced between 1983 and 2007, with an increase in annual mean temperature of 0.09°C yr-1 and a decrease in annual mean precipitation of 2.1 mm yr-1. Crop water consumption decreased between 1983 and 2007 for wheat (1.65 mm yr-1), naked oats (2.04 mm yr-1), and potatoes (3.85 mm yr-1). Potatoes and naked oats consume more water than wheat. Climate change has significantly impacted crop water consumption. Water consumption and rainfall during the growing season are positively correlated, while water consumption and active accumulated temperature are negatively correlated. Compared to precipitation, accumulated temperature has little impact on crop water consumption. Recent climate change has been detrimental for crop production in Wuchuan County. Adaptation to climate change should include efforts to breed drought-resistant crops and to develop drought-resistant cultivation techniques.

  16. Effects of land use/land cover and climate changes on surface runoff in a semi-humid and semi-arid transition zone in northwest China

    NASA Astrophysics Data System (ADS)

    Yin, Jing; He, Fan; Jiu Xiong, Yu; Qiu, Guo Yu

    2017-01-01

    Water resources, which are considerably affected by land use/land cover (LULC) and climate changes, are a key limiting factor in highly vulnerable ecosystems in arid and semi-arid regions. The impacts of LULC and climate changes on water resources must be assessed in these areas. However, conflicting results regarding the effects of LULC and climate changes on runoff have been reported in relatively large basins, such as the Jinghe River basin (JRB), which is a typical catchment (> 45 000 km2) located in a semi-humid and arid transition zone on the central Loess Plateau, northwest China. In this study, we focused on quantifying both the combined and isolated impacts of LULC and climate changes on surface runoff. We hypothesized that under climatic warming and drying conditions, LULC changes, which are primarily caused by intensive human activities such as the Grain for Green Program, will considerably alter runoff in the JRB. The Soil and Water Assessment Tool (SWAT) was adopted to perform simulations. The simulated results indicated that although runoff increased very little between the 1970s and the 2000s due to the combined effects of LULC and climate changes, LULC and climate changes affected surface runoff differently in each decade, e.g., runoff increased with increased precipitation between the 1970s and the 1980s (precipitation contributed to 88 % of the runoff increase). Thereafter, runoff decreased and was increasingly influenced by LULC changes, which contributed to 44 % of the runoff changes between the 1980s and 1990s and 71 % of the runoff changes between the 1990s and 2000s. Our findings revealed that large-scale LULC under the Grain for Green Program has had an important effect on the hydrological cycle since the late 1990s. Additionally, the conflicting findings regarding the effects of LULC and climate changes on runoff in relatively large basins are likely caused by uncertainties in hydrological simulations.

  17. Defining excellence.

    PubMed

    Mehl, B

    1993-05-01

    Excellence in the pharmacy profession, particularly pharmacy management, is defined. Several factors have a significant effect on the ability to reach a given level of excellence. The first is the economic and political climate in which pharmacists practice. Stricter controls, reduced resources, and the velocity of change all necessitate nurturing of values and a work ethic to maintain excellence. Excellence must be measured by the services provided with regard to the resources available; thus, the ability to achieve excellence is a true test of leadership and innovation. Excellence is also time dependent, and today's innovation becomes tomorrow's standard. Programs that raise the level of patient care, not those that aggrandize the profession, are the most important. In addition, basic services must be practiced at a level of excellence. Quality assessment is a way to improve care and bring medical treatment to a higher plane of excellence. For such assessment to be effective and not punitive, the philosophy of the program must be known, and the goal must be clear. Excellence in practice is dependent on factors such as political and social norms, standards of practice, available resources; perceptions, time, the motivation to progress to a higher level, and the continuous innovation required to reshape the profession to meet the needs of society.

  18. Late Quaternary slip rate gradient defined using high-resolution topography and 10Be dating of offset landforms on the southern San Jacinto Fault zone, California

    NASA Astrophysics Data System (ADS)

    Blisniuk, Kimberly; Rockwell, Thomas; Owen, Lewis A.; Oskin, Michael; Lippincott, Caitlin; Caffee, Marc W.; Dortch, Jason

    2010-08-01

    Recent studies suggest the San Jacinto fault zone may be the dominant structure accommodating PA-NA relative plate motion. However, because the late Quaternary slip history of the southern San Andreas fault system is insufficiently understood, it is difficult to evaluate the partitioning of deformation across the plate boundary and its evolution. Landforms displaced by the Clark fault of the southern San Jacinto fault zone were mapped using high-resolution airborne laser-swath topography and selected offset landforms were dated using cosmogenic 10Be. Beheaded channels at Rockhouse Canyon, displaced by 500 ± 70 m and 220 ± 70 m, have been dated to 47 ± 8 ka and 28 ± 9 ka, respectively. Farther south, near the southern Santa Rosa Mountains, an alluvial deposit displaced by 51 ± 9 m has been dated to 35 ± 7 ka. From these sites, the slip rate of the Clark fault is determined to diminish southward from 8.9 ± 2.0 to 1.5 ± 0.4 mm/yr. This implies a slip-rate decrease along the Clark fault from Anza southeastward to its surface termination near the Salton Trough, where slip is transferred to the Coyote Creek fault, and additional deformation is compensated by folding and thrusting in the basin. These data suggest that since ˜30 to 50 ka, the slip rate along the southern San Jacinto fault zone has been lower than, or equivalent to, the rate along the southernmost San Andreas fault. Accordingly, either the slip rate of the San Jacinto fault has substantially decreased since fault initiation, or fault slip began earlier than previously suggested.

  19. Clinal variation in a brown lemur (Eulemur spp.) hybrid zone: combining morphological, genetic and climatic data to examine stability.

    PubMed

    Delmore, K E; Brenneman, R A; Lei, R; Bailey, C A; Brelsford, A; Louis, E E; Johnson, S E

    2013-08-01

    Studies of hybrid zones can inform our understanding of reproductive isolation and speciation. Two species of brown lemur (Eulemur rufifrons and E. cinereiceps) form an apparently stable hybrid zone in the Andringitra region of southeastern Madagascar. The aim of this study was to identify factors that contribute to this stability. We sampled animals at 11 sites along a 90-km transect through the hybrid zone and examined variation in 26 microsatellites, the D-loop region of mitochondrial DNA, six pelage and nine morphological traits; we also included samples collected in more distant allopatric sites. Clines in these traits were noncoincident, and there was no increase in either inbreeding coefficients or linkage disequilibrium at the centre of the zone. These results could suggest that the hybrid zone is maintained by weak selection against hybrids, conforming to either the tension zone or geographical selection-gradient model. However, a closer examination of clines in pelage and microsatellites indicates that these clines are not sigmoid or stepped in shape but instead plateau at their centre. Sites within the hybrid zone also occur in a distinct habitat, characterized by greater seasonality in precipitation and lower seasonality in temperature. Together, these findings suggest that the hybrid zone may follow the bounded superiority model, with exogenous selection favouring hybrids within the transitional zone. These findings are noteworthy, as examples supporting the bounded superiority model are rare and may indicate a process of ecologically driven speciation without geographical isolation.

  20. How do climatic and management factors affect agricultural ecosystem services? A case study in the agro-pastoral transitional zone of northern China.

    PubMed

    Qiao, Jianmin; Yu, Deyong; Wu, Jianguo

    2017-09-13

    Agricultural ecosystem management needs to ensure food production and minimize soil erosion and nitrogen (N) leaching under climate change and increasingly intensive human activity. Thus, the mechanisms through which climatic and management factors affect crop production, soil erosion, and N leaching must be understood in order to ensure food security and sustainable agricultural development. In this study, we adopted the GIS-based Environmental Policy Integrated Climate (EPIC) model to simulate crop production, soil erosion, and N leaching, and used a partial least squares regression model to evaluate the contributions of climate variables (solar radiation, precipitation, wind speed, relative humidity, and maximum and minimum temperature) and management factors (irrigation, fertilization, and crop cultivation area) on agricultural ecosystem services (AES) in the agro-pastoral transitional zone (APTZ) of northern China. The results indicated that crop production and N leaching markedly increased, whereas soil erosion declined from 1980 to 2010 in the APTZ. Management factors had larger effects on the AES than climate change. Among the climatic variables, daily minimum temperature was the most important contributor to the variations in ecosystem services of wheat, maize, and rice. Spatial changes in the cultivated area most affected crop production, soil erosion, and N leaching for majority of the cultivated areas of the three crops, except for the wheat-cultivated area, where the dominant factor for N leaching was fertilization. Although a tradeoff existed between crop production and negative environmental effects, compromises were possible. These findings provide new insights into the effects of climatic and management factors on AES, and have practical implications for improving crop production while minimizing negative environmental impacts. Copyright © 2017. Published by Elsevier B.V.

  1. GEOPHYSICS AND SITE CHARACTERIZATION AT THE HANFORD SITE THE SUCCESSFUL USE OF ELECTRICAL RESISTIVITY TO POSITION BOREHOLES TO DEFINE DEEP VADOSE ZONE CONTAMINATION - 11509

    SciTech Connect

    GANDER MJ; LEARY KD; LEVITT MT; MILLER CW

    2011-01-14

    Historic boreholes confirmed the presence of nitrate and radionuclide contaminants at various intervals throughout a more than 60 m (200 ft) thick vadose zone, and a 2010 electrical resistivity survey mapped the known contamination and indicated areas of similar contaminants, both laterally and at depth; therefore, electrical resistivity mapping can be used to more accurately locate characterization boreholes. At the Hanford Nuclear Reservation in eastern Washington, production of uranium and plutonium resulted in the planned release of large quantities of contaminated wastewater to unlined excavations (cribs). From 1952 until 1960, the 216-U-8 Crib received approximately 379,000,000 L (100,000,000 gal) of wastewater containing 25,500 kg (56,218 lb) uranium; 1,029,000 kg (1,013 tons) of nitrate; 2.7 Ci of technetium-99; and other fission products including strontium-90 and cesium-137. The 216-U-8 Crib reportedly holds the largest inventory of waste uranium of any crib on the Hanford Site. Electrical resistivity is a geophysical technique capable of identifying contrasting physical properties; specifically, electrically conductive material, relative to resistive native soil, can be mapped in the subsurface. At the 216-U-8 Crib, high nitrate concentrations (from the release of nitric acid [HNO{sub 3}] and associated uranium and other fission products) were detected in 1994 and 2004 boreholes at various depths, such as at the base of the Crib at 9 m (30 ft) below ground surface (bgs) and sporadically to depths in excess of 60 m (200 ft) bgs. These contaminant concentrations were directly correlative with the presence of observed low electrical resistivity responses delineated during the summer 2010 geophysical survey. Based on this correlation and the recently completed mapping of the electrically conductive material, additional boreholes are planned for early 2011 to identify nitrate and radionuclide contamination: (a) throughout the entire vertical length of the

  2. Seismic reflection-based evidence of a transfer zone between the Wagner and Consag basins: implications for defining the structural geometry of the northern Gulf of California

    NASA Astrophysics Data System (ADS)

    González-Escobar, Mario; Suárez-Vidal, Francisco; Hernández-Pérez, José Antonio; Martín-Barajas, Arturo

    2010-12-01

    This study examines the structural characteristics of the northern Gulf of California by processing and interpreting ca. 415 km of two-dimensional multi-channel seismic reflection lines (data property of Petróleos Mexicanos PEMEX) collected in the vicinity of the border between the Wagner and Consag basins. The two basins appear to be a link between the Delfín Superior Basin to the south, and the Cerro Prieto Basin to the north in the Mexicali-Imperial Valley along the Pacific-North America plate boundary. The seismic data are consistent with existing knowledge of four main structures (master faults) in the region, i.e., the Percebo, Santa María, Consag Sur, and Wagner Sur faults. The Wagner and Consag basins are delimited to the east by the Wagner Sur Fault, and to the west by the Consag Sur Fault. The Percebo Fault borders the western margin of the modern Wagner Basin depocenter, and is oriented N10°W, dipping (on average) ˜40° to the northeast. The trace of the Santa María Fault located in the Wagner Basin strikes N19°W, dipping ˜40° to the west. The Consag Sur Fault is oriented N14°W, and dips ˜42° to the east over a distance of 21 km. To the east of the study area, the Wagner Sur Fault almost parallels the Consag Sur Fault over a distance of ˜86 km, and is oriented N10°W with an average dip of 59° to the east. Moreover, the data provide new evidence that the Wagner Fault is discontinuous between the two basins, and that its structure is more complex than previously reported. A structural high separates the northern Consag Basin from the southern Wagner Basin, comprising several secondary faults oriented NE oblique to the main faults of N-S direction. These could represent a zone of accommodation, or transfer zone, where extension could be transferred from the Wagner to the Consag Basin, or vice versa. This area shows no acoustic basement and/or intrusive body, which is consistent with existing gravimetric and magnetic data for the region.

  3. Inference of the Arabidopsis Lateral Root Gene Regulatory Network Suggests a Bifurcation Mechanism That Defines Primordia Flanking and Central Zones[OPEN

    PubMed Central

    Lavenus, Julien; Goh, Tatsuaki; Guyomarc’h, Soazig; Hill, Kristine; Lucas, Mikael; Voß, Ute; Kenobi, Kim; Wilson, Michael H.; Farcot, Etienne; Hagen, Gretchen; Guilfoyle, Thomas J.; Fukaki, Hidehiro; Laplaze, Laurent; Bennett, Malcolm J.

    2015-01-01

    A large number of genes involved in lateral root (LR) organogenesis have been identified over the last decade using forward and reverse genetic approaches in Arabidopsis thaliana. Nevertheless, how these genes interact to form a LR regulatory network largely remains to be elucidated. In this study, we developed a time-delay correlation algorithm (TDCor) to infer the gene regulatory network (GRN) controlling LR primordium initiation and patterning in Arabidopsis from a time-series transcriptomic data set. The predicted network topology links the very early-activated genes involved in LR initiation to later expressed cell identity markers through a multistep genetic cascade exhibiting both positive and negative feedback loops. The predictions were tested for the key transcriptional regulator AUXIN RESPONSE FACTOR7 node, and over 70% of its targets were validated experimentally. Intriguingly, the predicted GRN revealed a mutual inhibition between the ARF7 and ARF5 modules that would control an early bifurcation between two cell fates. Analyses of the expression pattern of ARF7 and ARF5 targets suggest that this patterning mechanism controls flanking and central zone specification in Arabidopsis LR primordia. PMID:25944102

  4. The regional variation of denitrification phenotypes under anoxic incubation with soils from eight forested catchments in different climate zones of China.

    PubMed

    Cui, Juan; Zhu, Jing; Wang, Zhangwei; Mulder, Jan; Wang, Bing; Zhang, Xiaoshan

    2017-10-02

    Denitrification characteristics of forest soils from eight headwater catchments in China were investigated in this study, along a climatic gradient from the tropics in the South to the temperate zones. Within each catchment, different landscape positions along hydrological flow paths were also considered, including well-drained soils on hill slopes and poorly drained soils in groundwater discharge zones. The results showed that instantaneous denitrification rates were much greater in soils from the northern sites than those from the southern sites (with the average of 110.0 and 25.4nmolNg(-1)drysoilh.(-)(1), respectively). Large potentials for nitrous oxide (N2O) loss (evaluated as maximum N2O accumulation before it was reduced to dinitrogen (N2)) were observed in the six tropical and subtropical catchments, particularly in soils with high carbon (C) and nitrogen (N). Meanwhile high N2O/(N2O+N2) stoichiometries were displayed in soils from these southern sites. Within catchments, soils from the groundwater discharge zones showed greater potential denitrification rates but smaller N2O/(N2O+N2) ratios in comparison with those on the hill slopes, implying large N removal potentials of soils from the groundwater discharge zones. Furthermore, our findings suggest soil pH is the key controller for the potential denitrification rates and the N2O/(N2O+N2) stoichiometries. Soil pH, C and N availability affect the potential for N2O loss synergistically. Our findings not only pinpoint the denitrification phenotypes of soils along the climatic gradient, but also confirm the small-scale variations within catchments which reflect the in situ habitat of the denitrifiers. These indicate the importance of discrimination related to different landscape positions when modeling N2O emissions and N removals from regional N loading. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Mortality during a Large-Scale Heat Wave by Place, Demographic Group, Internal and External Causes of Death, and Building Climate Zone

    PubMed Central

    Joe, Lauren; Hoshiko, Sumi; Dobraca, Dina; Jackson, Rebecca; Smorodinsky, Svetlana; Smith, Daniel; Harnly, Martha

    2016-01-01

    Mortality increases during periods of elevated heat. Identification of vulnerable subgroups by demographics, causes of death, and geographic regions, including deaths occurring at home, is needed to inform public health prevention efforts. We calculated mortality relative risks (RRs) and excess deaths associated with a large-scale California heat wave in 2006, comparing deaths during the heat wave with reference days. For total (all-place) and at-home mortality, we examined risks by demographic factors, internal and external causes of death, and building climate zones. During the heat wave, 582 excess deaths occurred, a 5% increase over expected (RR = 1.05, 95% confidence interval (CI) 1.03–1.08). Sixty-six percent of excess deaths were at home (RR = 1.12, CI 1.07–1.16). Total mortality risk was higher among those aged 35–44 years than ≥65, and among Hispanics than whites. Deaths from external causes increased more sharply (RR = 1.18, CI 1.10–1.27) than from internal causes (RR = 1.04, CI 1.02–1.07). Geographically, risk varied by building climate zone; the highest risks of at-home death occurred in the northernmost coastal zone (RR = 1.58, CI 1.01–2.48) and the southernmost zone of California’s Central Valley (RR = 1.43, CI 1.21–1.68). Heat wave mortality risk varied across subpopulations, and some patterns of vulnerability differed from those previously identified. Public health efforts should also address at-home mortality, non-elderly adults, external causes, and at-risk geographic regions. PMID:27005646

  6. Mortality during a Large-Scale Heat Wave by Place, Demographic Group, Internal and External Causes of Death, and Building Climate Zone.

    PubMed

    Joe, Lauren; Hoshiko, Sumi; Dobraca, Dina; Jackson, Rebecca; Smorodinsky, Svetlana; Smith, Daniel; Harnly, Martha

    2016-03-09

    Mortality increases during periods of elevated heat. Identification of vulnerable subgroups by demographics, causes of death, and geographic regions, including deaths occurring at home, is needed to inform public health prevention efforts. We calculated mortality relative risks (RRs) and excess deaths associated with a large-scale California heat wave in 2006, comparing deaths during the heat wave with reference days. For total (all-place) and at-home mortality, we examined risks by demographic factors, internal and external causes of death, and building climate zones. During the heat wave, 582 excess deaths occurred, a 5% increase over expected (RR = 1.05, 95% confidence interval (CI) 1.03-1.08). Sixty-six percent of excess deaths were at home (RR = 1.12, CI 1.07-1.16). Total mortality risk was higher among those aged 35-44 years than ≥ 65, and among Hispanics than whites. Deaths from external causes increased more sharply (RR = 1.18, CI 1.10-1.27) than from internal causes (RR = 1.04, CI 1.02-1.07). Geographically, risk varied by building climate zone; the highest risks of at-home death occurred in the northernmost coastal zone (RR = 1.58, CI 1.01-2.48) and the southernmost zone of California's Central Valley (RR = 1.43, CI 1.21-1.68). Heat wave mortality risk varied across subpopulations, and some patterns of vulnerability differed from those previously identified. Public health efforts should also address at-home mortality, non-elderly adults, external causes, and at-risk geographic regions.

  7. Database of Low-E Storm Window Energy Performance across U.S. Climate Zones (Task ET-WIN-PNNL-FY13-01_5.3)

    SciTech Connect

    Cort, Katherine A.; Culp, Thomas D.

    2013-09-01

    This report describes process, assumptions, and modeling results produced in support of the Emerging Technologies Low-e Storm Windows Task 5.3: Create a Database of U.S. Climate-Based Analysis for Low-E Storm Windows. The scope of the overall effort is to develop a database of energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by cliamte zone. Both sets of calculation results will be made publicly available through the Building America Solution Center.

  8. Data and Knowledge Base on the Basis of the Expanded Matrix Model of Their Representation for the Intelligent System of Road-Climatic Zoning of Territories

    NASA Astrophysics Data System (ADS)

    Yankovskaya, A.; Cherepanov, D.; Selivanikova, O.

    2016-08-01

    An extended matrix model of data and knowledge representation on the investigated area, as well as a matrix model of data representation on the territory under investigation, are proposed for the intelligent system of road-climatic zoning of territories (RCZT) - the main information technology of RCZT. A part of the West Siberian region has been selected as the investigated territory. The extended matrix model of knowledge representation is filled out by knowledge engineers with participation of highly qualified experts in the field of RCZT. The matrix model of data representation on the territory under investigation is filled out by persons concerned in RCZT of the motor-roads management system.

  9. An abrupt centennial-scale drought event and mid-holocene climate change patterns in monsoon marginal zones of East Asia.

    PubMed

    Li, Yu; Wang, Nai'ang; Zhang, Chengqi

    2014-01-01

    The mid-latitudes of East Asia are characterized by the interaction between the Asian summer monsoon and the westerly winds. Understanding long-term climate change in the marginal regions of the Asian monsoon is critical for understanding the millennial-scale interactions between the Asian monsoon and the westerly winds. Abrupt climate events are always associated with changes in large-scale circulation patterns; therefore, investigations into abrupt climate changes provide clues for responses of circulation patterns to extreme climate events. In this paper, we examined the time scale and mid-Holocene climatic background of an abrupt dry mid-Holocene event in the Shiyang River drainage basin in the northwest margin of the Asian monsoon. Mid-Holocene lacustrine records were collected from the middle reaches and the terminal lake of the basin. Using radiocarbon and OSL ages, a centennial-scale drought event, which is characterized by a sand layer in lacustrine sediments both from the middle and lower reaches of the basin, was absolutely dated between 8.0-7.0 cal kyr BP. Grain size data suggest an abrupt decline in lake level and a dry environment in the middle reaches of the basin during the dry interval. Previous studies have shown mid-Holocene drought events in other places of monsoon marginal zones; however, their chronologies are not strong enough to study the mechanism. According to the absolutely dated records, we proposed a new hypothesis that the mid-Holocene dry interval can be related to the weakening Asian summer monsoon and the relatively arid environment in arid Central Asia. Furthermore, abrupt dry climatic events are directly linked to the basin-wide effective moisture change in semi-arid and arid regions. Effective moisture is affected by basin-wide precipitation, evapotranspiration, lake surface evaporation and other geographical settings. As a result, the time scales of the dry interval could vary according to locations due to different geographical

  10. An Abrupt Centennial-Scale Drought Event and Mid-Holocene Climate Change Patterns in Monsoon Marginal Zones of East Asia

    PubMed Central

    Li, Yu; Wang, Nai'ang; Zhang, Chengqi

    2014-01-01

    The mid-latitudes of East Asia are characterized by the interaction between the Asian summer monsoon and the westerly winds. Understanding long-term climate change in the marginal regions of the Asian monsoon is critical for understanding the millennial-scale interactions between the Asian monsoon and the westerly winds. Abrupt climate events are always associated with changes in large-scale circulation patterns; therefore, investigations into abrupt climate changes provide clues for responses of circulation patterns to extreme climate events. In this paper, we examined the time scale and mid-Holocene climatic background of an abrupt dry mid-Holocene event in the Shiyang River drainage basin in the northwest margin of the Asian monsoon. Mid-Holocene lacustrine records were collected from the middle reaches and the terminal lake of the basin. Using radiocarbon and OSL ages, a centennial-scale drought event, which is characterized by a sand layer in lacustrine sediments both from the middle and lower reaches of the basin, was absolutely dated between 8.0–7.0 cal kyr BP. Grain size data suggest an abrupt decline in lake level and a dry environment in the middle reaches of the basin during the dry interval. Previous studies have shown mid-Holocene drought events in other places of monsoon marginal zones; however, their chronologies are not strong enough to study the mechanism. According to the absolutely dated records, we proposed a new hypothesis that the mid-Holocene dry interval can be related to the weakening Asian summer monsoon and the relatively arid environment in arid Central Asia. Furthermore, abrupt dry climatic events are directly linked to the basin-wide effective moisture change in semi-arid and arid regions. Effective moisture is affected by basin-wide precipitation, evapotranspiration, lake surface evaporation and other geographical settings. As a result, the time scales of the dry interval could vary according to locations due to different

  11. Assessing the hydrological response from an ensemble of CMIP5 climate projections in the transition zone of the Atlantic region (Bay of Biscay)

    NASA Astrophysics Data System (ADS)

    Meaurio, Maite; Zabaleta, Ane; Boithias, Laurie; Epelde, Ane Miren; Sauvage, Sabine; Sánchez-Pérez, Jose-Miguel; Srinivasan, Raghavan; Antiguedad, Iñaki

    2017-05-01

    The climate changes projected for the 21st century will have consequences on the hydrological response of catchments. These changes, and their consequences, are most uncertain in the transition zones. The study area, in the Bay of Biscay, is located in the transition zone of the European Atlantic region, where hydrological impact of climate change was scarcely studied. In order to address this scarcity, the hydrological impacts of climate change on river discharge were assessed. To do so, a hydrological modelling was carried out considering 16 climate scenarios that include 5 General Circulation Models (GCM) from the 5th report of the Coupled Model Intercomparison Project (CMIP5), 2 statistical downscaling methods and 2 Representative Concentration Pathways. Projections for future discharge (2011-2100) were divided into three 30-year horizons (2030s, 2060s and 2090s) and a comparison was made between these time horizons and the baseline (1961-2000). The results show that the downscaling method used resulted in a higher source of uncertainty than GCM itself. In addition, the uncertainties inherent to the methods used at all the levels do not affect the results equally along the year. In spite of those uncertainties, general trends for the 2090s predict seasonal discharge decreases by around -17% in autumn, -16% in spring, -11% in winter and -7% in summer. These results are in line with those predicted for the Atlantic region (France and the Iberian Peninsula). Trends for extreme flows were also analysed: the most significant show an increase in the duration (days) of low flows. From an environmental point of view, and considering the need to meet the objectives established by the Water Framework Directive (WFD), this will be a major challenge for the future planning on water management.

  12. Forest expansion and climate change in the Mountain Hemlock (Tsuga mertensiana) zone, Lassen Volcanic National Park, California, U.S.A.

    SciTech Connect

    Taylor, A.H.

    1995-08-01

    The relationship between climate change and the dynamics of ecotonal populations of mountain hemlock (Tsuga mertensiana [Bong.] Carr.) was determined by comparing climate and the age structure of trees from 24 plots and seedlings from 13 plots in the subalpine zone of Lassen Volcanic National Park, California. Tree establishment was greatest during periods with above normal annual and summer temperatures, and normal or above normal precipitation. Seedling establishment was positively correlated with above normal annual and summer temperatures and negatively correlated with April snowpack depth. The different responses of trees and seedlings to precipitation variation is probably related to site soil moisture conditions. Mountain hemlock populations began to expand in 1842 and establishment increased dramatically after 1880 and peaked during a warm mesic period between 1895 and 1910. The onset of forest expansion coincides with warming that began at the end of the Little Ice Age (1850-1880). These data indicate that stability of the mountain hemlock ecotone is strongly influenced by climate. If warming induced by greenhouse gases does occur as climate models predict, then the structure and dynamics of near timberline forests in the Pacific Northwest will change. 52 refs., 8 figs., 3 tabs.

  13. Monitoring and Modelling of Soil-Plant Interactions: the Joint Use of ERT, Sap Flow and Eddy Covariance to Define the Volume of Orange Tree Active Root Zones.

    NASA Astrophysics Data System (ADS)

    Cassiani, G.; Boaga, J.; Vanella, D.; Perri, M. T.; Consoli, S.

    2014-12-01

    Mass and energy exchanges between soil, plants and atmosphere are key factors controlling a number of environmental processes involving hydrology, biota and climate. The understanding of these exchanges also play a critical role for practical purposes such as precision agriculture. In this contribution we present a methodology based on coupling innovative data collection and models. In particular we propose the use of hydro-geophysical monitoring via 4D Electrical Resistivity Tomography (ERT) in conjunction with measurements of plant transpiration via sap flow and evapotranspiration from Eddy Correlation (EC). This abundance of data are to be fed in spatially distributed soil models in order to comprehend the distribution of active roots. We conducted experiments in an orange orchard in Eastern Sicily (Italy). We installed a 3D electrical tomography apparatus consisting of 4 instrumented micro boreholes placed at the corners of a square (about 1.3 m in side) surrounding an orange tree. During the monitoring, we collected repeated ERT and TDR soil moisture measurements, soil water sampling, sap flow measurements from the orange tree and EC data. Irrigation, precipitation, sap flow and ET data are available for a long period of time allowing knowledge of the long term forcing conditions on the system. This wealth of information was used to calibrate a 1D Richards' equation model representing the dynamics of the volume monitored via 3D ERT. Information on the soil hydraulic properties was collected from laboratory experiments as well as by time-lapse ERT monitoring of irrigation a few months after the main experiment, when the orange tree had been cut. The results of the calibrated modeling exercise allow the quantification of the soil volume interested by root water uptake. This volume is much smaller (an area less than 2 square meters, 40 cm thick) than generally believed and assumed in the design of classical drip irrigation schemes.

  14. Regional variations in the female age at marriage in India: an analysis by agro-climatic zones.

    PubMed

    Mishra, V; Singh, V

    1992-01-01

    "The effect of agro-climatic factors on female age at marriage [in India] is studied by carrying out areal analysis of the 1981 Census data. The study found a close association between agricultural and climatic conditions in an area and corresponding female age at marriage. In general, women in Himalayan regions and coastal areas have higher age at marriage than most hinterland regions. Rainfall, altitude, forest area, land availability and productivity are observed to be associated with female age at marriage. In addition, female age at marriage in rural areas is found to be more sensitive to the agro-climatic conditions. It is hypothesized that with socio-economic and technological development, the agricultural and climatic factors are losing their grip on female age at marriage in India."

  15. School Climate.

    ERIC Educational Resources Information Center

    Lindelow, John; And Others

    Chapter 8 of a revised volume on school leadership, this chapter defines school climate and suggests ways to improve the learning environment at the school building level. School climate is defined as the feeling an individual gets from experiences within a school system. More specifically, climate is the composite of norms, expectations, and…

  16. Regional and Large-Scale Climate Influences on Tree-Ring Reconstructed Null Zone Position in San Francisco Bay

    NASA Astrophysics Data System (ADS)

    Stahle, D.; Griffin, D.; Cleaveland, M.; Fye, F.; Meko, D.; Cayan, D.; Dettinger, M.; Redmond, K.

    2007-05-01

    A new network of 36 moisture sensitive tree-ring chronologies has been developed in and near the drainage basins of the Sacramento and San Joaquin Rivers. The network is based entirely on blue oak (Quercus douglasii), which is a California endemic found from the lower forest border up into the mixed conifer zone in the Coast Ranges, Sierra Nevada, and Cascades. These blue oak tree-ring chronologies are highly correlated with winter-spring precipitation totals, Sacramento and San Joaquin streamflow, and with seasonal variations in salinity and null zone position in San Francisco Bay. Null zone is the non-tidal bottom water location where density-driven salinity and river-driven freshwater currents balance (zero flow). It is the area of highest turbidity, water residence time, sediment accumulation, and net primary productivity in the estuary. Null zone position is measured by the distance from the Golden Gate of the 2 per mil bottom water isohaline and is primarily controlled by discharge from the Sacramento and San Joaquin Rivers (and ultimately by winter-spring precipitation). The location of the null zone is an estuarine habitat indicator, a policy variable used for ecosystem management, and can have a major impact on biological resources in the San Francisco estuary. Precipitation-sensitive blue oak chronologies can be used to estimate null zone position based on the strong biogeophysical interaction among terrestrial, aquatic, and estuarine ecosystems, orchestrated by precipitation. The null zone reconstruction is 626-years long and provides a unique long term perspective on the interannual to decadal variability of this important estuarine habitat indicator. Consecutive two-year droughts (or longer) allow the null zone to shrink into the confined upper reaches of Suisun Bay, causing a dramatic reduction in phytoplankton production and favoring colonization of the estuary by marine biota. The reconstruction indicates an approximate 10 year recurrence interval

  17. Ecological functions of riparian zones in Oregon hydrological landscapes

    EPA Science Inventory

    The ecological functions of streams and associated riparian zones are strongly influenced by the hydrological attributes of watersheds and landscapes in which they occur. Oregon hydrologic landscape regions (HLRs) have been defined based on four types of GIS data: 1) climate, 2) ...

  18. Ecological functions of riparian zones in Oregon hydrological landscapes

    EPA Science Inventory

    The ecological functions of streams and associated riparian zones are strongly influenced by the hydrological attributes of watersheds and landscapes in which they occur. Oregon hydrologic landscape regions (HLRs) have been defined based on four types of GIS data: 1) climate, 2) ...

  19. Influence of two different geo-climatic zones on the prevalence and time trends of asthma symptoms among Spanish adolescents and schoolchildren

    NASA Astrophysics Data System (ADS)

    García-Marcos, Luis; Batllés-Garrido, José; Blanco-Quirós, Alfredo; García-Hernández, Gloria; Guillén-Grima, Francisco; González-Díaz, Carlos; García-Merino, Águeda; Arnedo-Pena, Alberto; Busquets-Monge, Rosa M.; Morales-Suárez-Varela, María; López-Silvarrey-Varela, Ángel; García-Andoin, Nekane

    2009-01-01

    Few studies have focused on the long-term influence of the climate on the prevalence of asthma. The aim of this study is to establish the influence of geo-climatic conditions on the prevalence of asthma symptoms both in adolescents and schoolchildren, and to discover if this influence is associated with their time trends. Eight centres in Spain performed both ISAAC phases I (1994) and III (2002) in children 13-14 years old. Six of them also surveyed children 6-7 years old. For each age group and phase, about 3,000 children were surveyed per centre. This study examines the prevalence of current wheeze and severe current wheeze in two different geo-climatic zones, coast and plateau, considering their relative humidity and temperature range. In both age groups, the mean asthma prevalence on the coast, for phase I and III, was significantly higher than on the plateau. Living on the plateau was an independent protective factor for current wheeze and severe current wheeze for the two age groups. Within the coastal centres, the increase of the annual relative humidity was a statistical significant risk factor for current wheeze, the same trend existing for current severe wheeze. These effects were independent of the sex and of the phase of the study. The prevalence of asthma and severe asthma symptoms is more frequent on the coast of Spain as compared to the inner plateau. This finding was repeated both in 1994 and in 2002.

  20. Climatically related millennial-scale fluctuations in strength of California margin oxygen-minimum zone during the past 60 k.y.

    SciTech Connect

    Cannariato, K.G.; Kennett, J.P.

    1999-11-01

    A strong oxygen-minimum zone (OMZ) currently exists along the California margin because of a combination of high surface-water productivity and poor intermediate-water ventilation. However, the strength of this OMZ may have been sensitive to late Quaternary ocean-circulation and productivity changes along the margin. Although sediment-lamination strength has been used to trace ocean-oxygenation changes in the past, oxygen levels on the open margin are not sufficiently low for laminations to form. In these regions, benthic foraminifera are highly sensitive monitors of OMZ strength, and their fossil assemblages can be used to reconstruct past fluctuations. Benthic foraminiferal assemblages from Ocean Drilling Program Site 1017, off Point Conception, exhibit major and rapid faunal oscillations in response to late Quaternary millennial-scale climate change (Dansgaard-Oeschger cycles) on the open central California margin. These faunal oscillations can be correlated to and are apparently synchronous with those reported from Santa Barbara Basin. Together they represent major fluctuations in the strength of the OMZ which were intimately associated with global climate change--weakening, perhaps disappearing, during cool periods and strengthening during warm periods. These rapid, major OMZ strength fluctuations were apparently widespread on the Northeast Pacific margin and must have influenced the evolution of margin biota and altered biogeochemical cycles with potential feedbacks to global climate change.

  1. Dynamics and controls of urban heat sink and island phenomena in a desert city: Development of a local climate zone scheme using remotely-sensed inputs

    NASA Astrophysics Data System (ADS)

    Nassar, Ahmed K.; Blackburn, G. Alan; Whyatt, J. Duncan

    2016-09-01

    This study aims to determine the dynamics and controls of Surface Urban Heat Sinks (SUHS) and Surface Urban Heat Islands (SUHI) in desert cities, using Dubai as a case study. A Local Climate Zone (LCZ) schema was developed to subdivide the city into different zones based on similarities in land cover and urban geometry. Proximity to the Gulf Coast was also determined for each LCZ. The LCZs were then used to sample seasonal and daily imagery from the MODIS thermal sensor to determine Land Surface Temperature (LST) variations relative to desert sand. Canonical correlation techniques were then applied to determine which factors explained the variability between urban and desert LST. Our results indicate that the daytime SUHS effect is greatest during the summer months (typically ∼3.0 °C) with the strongest cooling effects in open high-rise zones of the city. In contrast, the night-time SUHI effect is greatest during the winter months (typically ∼3.5 °C) with the strongest warming effects in compact mid-rise zones of the city. Proximity to the Arabian Gulf had the largest influence on both SUHS and SUHI phenomena, promoting daytime cooling in the summer months and night-time warming in the winter months. However, other parameters associated with the urban environment such as building height had an influence on daytime cooling, with larger buildings promoting shade and variations in airflow. Likewise, other parameters such as sky view factor contributed to night-time warming, with higher temperatures associated with limited views of the sky.

  2. Patterns of divergence across the geographic and genomic landscape of a butterfly hybrid zone associated with a climatic gradient

    USDA-ARS?s Scientific Manuscript database

    The process of speciation is impacted by the interaction between the genomic architecture of diverging lineages and the environmental context they occupy. Yet, while climate can have a significant impact on this interaction, its role in determining the patterns of geographic and genomic divergence i...

  3. Future climate change is predicted to shift long-term persistence zones in the cold-temperate kelp Laminaria hyperborea.

    PubMed

    Assis, Jorge; Lucas, Ana Vaz; Bárbara, Ignacio; Serrão, Ester Álvares

    2016-02-01

    Global climate change is shifting species distributions worldwide. At rear edges (warmer, low latitude range margins), the consequences of small variations in environmental conditions can be magnified, producing large negative effects on species ranges. A major outcome of shifts in distributions that only recently received attention is the potential to reduce the levels of intra-specific diversity and consequently the global evolutionary and adaptive capacity of species to face novel disturbances. This is particularly important for low dispersal marine species, such as kelps, that generally retain high and unique genetic diversity at rear ranges resulting from long-term persistence, while ranges shifts during climatic glacial/interglacial cycles. Using ecological niche modelling, we (1) infer the major environmental forces shaping the distribution of a cold-temperate kelp, Laminaria hyperborea (Gunnerus) Foslie, and we (2) predict the effect of past climate changes in shaping regions of long-term persistence (i.e., climatic refugia), where this species might hypothetically harbour higher genetic diversity given the absence of bottlenecks and local extinctions over the long term. We further (3) assessed the consequences of future climate for the fate of L. hyperborea using different scenarios of greenhouse gas emissions (RCP 2.6 and RCP 8.5). Results show NW Iberia, SW Ireland and W English Channel, Faroe Islands and S Iceland, as regions where L. hyperborea may have persisted during past climate extremes until present day. All predictions for the future showed expansions to northern territories coupled with the significant loss of suitable habitats at low latitude range margins, where long-term persistence was inferred (e.g., NW Iberia). This pattern was particularly evident in the most agressive scenario of climate change (RCP 8.5), likely driving major biodiversity loss, changes in ecosystem functioning and the impoverishment of the global gene pool of L

  4. Collaborative Project: The problem of bias in defining uncertainty in computationally enabled strategies for data-driven climate model development. Final Technical Report.

    SciTech Connect

    Huerta, Gabriel

    2016-05-10

    The objective of the project is to develop strategies for better representing scientific sensibilities within statistical measures of model skill that then can be used within a Bayesian statistical framework for data-driven climate model development and improved measures of model scientific uncertainty. One of the thorny issues in model evaluation is quantifying the effect of biases on climate projections. While any bias is not desirable, only those biases that affect feedbacks affect scatter in climate projections. The effort at the University of Texas is to analyze previously calculated ensembles of CAM3.1 with perturbed parameters to discover how biases affect projections of global warming. The hypothesis is that compensating errors in the control model can be identified by their effect on a combination of processes and that developing metrics that are sensitive to dependencies among state variables would provide a way to select version of climate models that may reduce scatter in climate projections. Gabriel Huerta at the University of New Mexico is responsible for developing statistical methods for evaluating these field dependencies. The UT effort will incorporate these developments into MECS, which is a set of python scripts being developed at the University of Texas for managing the workflow associated with data-driven climate model development over HPC resources. This report reflects the main activities at the University of New Mexico where the PI (Huerta) and the Postdocs (Nosedal, Hattab and Karki) worked on the project.

  5. Tradeoffs between Maize Silage Yield and Nitrate Leaching in a Mediterranean Nitrate-Vulnerable Zone under Current and Projected Climate Scenarios

    PubMed Central

    Basso, Bruno; Giola, Pietro; Dumont, Benjamin; Migliorati, Massimiliano De Antoni; Cammarano, Davide; Pruneddu, Giovanni; Giunta, Francesco

    2016-01-01

    Future climatic changes may have profound impacts on cropping systems and affect the agronomic and environmental sustainability of current N management practices. The objectives of this work were to i) evaluate the ability of the SALUS crop model to reproduce experimental crop yield and soil nitrate dynamics results under different N fertilizer treatments in a farmer’s field, ii) use the SALUS model to estimate the impacts of different N fertilizer treatments on NO3- leaching under future climate scenarios generated by twenty nine different global circulation models, and iii) identify the management system that best minimizes NO3- leaching and maximizes yield under projected future climate conditions. A field experiment (maize-triticale rotation) was conducted in a nitrate vulnerable zone on the west coast of Sardinia, Italy to evaluate N management strategies that include urea fertilization (NMIN), conventional fertilization with dairy slurry and urea (CONV), and no fertilization (N0). An ensemble of 29 global circulation models (GCM) was used to simulate different climate scenarios for two Representative Circulation Pathways (RCP6.0 and RCP8.5) and evaluate potential nitrate leaching and biomass production in this region over the next 50 years. Data collected from two growing seasons showed that the SALUS model adequately simulated both nitrate leaching and crop yield, with a relative error that ranged between 0.4% and 13%. Nitrate losses under RCP8.5 were lower than under RCP6.0 only for NMIN. Accordingly, levels of plant N uptake, N use efficiency and biomass production were higher under RCP8.5 than RCP6.0. Simulations under both RCP scenarios indicated that the NMIN treatment demonstrated both the highest biomass production and NO3- losses. The newly proposed best management practice (BMP), developed from crop N uptake data, was identified as the optimal N fertilizer management practice since it minimized NO3- leaching and maximized biomass production over

  6. Tradeoffs between Maize Silage Yield and Nitrate Leaching in a Mediterranean Nitrate-Vulnerable Zone under Current and Projected Climate Scenarios.

    PubMed

    Basso, Bruno; Giola, Pietro; Dumont, Benjamin; Migliorati, Massimiliano De Antoni; Cammarano, Davide; Pruneddu, Giovanni; Giunta, Francesco

    2016-01-01

    Future climatic changes may have profound impacts on cropping systems and affect the agronomic and environmental sustainability of current N management practices. The objectives of this work were to i) evaluate the ability of the SALUS crop model to reproduce experimental crop yield and soil nitrate dynamics results under different N fertilizer treatments in a farmer's field, ii) use the SALUS model to estimate the impacts of different N fertilizer treatments on NO3- leaching under future climate scenarios generated by twenty nine different global circulation models, and iii) identify the management system that best minimizes NO3- leaching and maximizes yield under projected future climate conditions. A field experiment (maize-triticale rotation) was conducted in a nitrate vulnerable zone on the west coast of Sardinia, Italy to evaluate N management strategies that include urea fertilization (NMIN), conventional fertilization with dairy slurry and urea (CONV), and no fertilization (N0). An ensemble of 29 global circulation models (GCM) was used to simulate different climate scenarios for two Representative Circulation Pathways (RCP6.0 and RCP8.5) and evaluate potential nitrate leaching and biomass production in this region over the next 50 years. Data collected from two growing seasons showed that the SALUS model adequately simulated both nitrate leaching and crop yield, with a relative error that ranged between 0.4% and 13%. Nitrate losses under RCP8.5 were lower than under RCP6.0 only for NMIN. Accordingly, levels of plant N uptake, N use efficiency and biomass production were higher under RCP8.5 than RCP6.0. Simulations under both RCP scenarios indicated that the NMIN treatment demonstrated both the highest biomass production and NO3- losses. The newly proposed best management practice (BMP), developed from crop N uptake data, was identified as the optimal N fertilizer management practice since it minimized NO3- leaching and maximized biomass production over the

  7. Satellite monitoring of spatio-temporal dynamics of China's coastal zone eco-environments: preliminary analysis on the relationship between the environment, climate change and human behavior

    NASA Astrophysics Data System (ADS)

    Qin, Q.; Zhu, L.; Ghulam, A.; Li, Z.; Nan, P.

    2008-10-01

    In this paper, temporal dynamics of eco-environmental changes in coastal areas of China during 1981-2000 are investigated based on four key surface parameters including normalized difference vegetation index (NDVI), thermal index, moisture index and surface broadband albedo derived from quantitative remote sensing techniques and meteorological data. Firstly, land surface temperature (LST) and land surface broadband albedo are retrieved by the split-window algorithms and high-order polynomial regression method, respectively, using NOAA/AVHRR series images. Then, moisture index and thermal index, indicators of climate and moisture conditions in the study area, are computed from meteorological data and LST using principal component analysis (PCA). Finally, long-term dynamics of these eco-environmental factors and the reasons responsible for these changes are analyzed further. The results show that during the years from 1981 to 2000, the study area experienced a gradual increase in annual NDVI and climate factors and a decrease in surface annual broadband albedo, which indicates that the coastal thermal and moisture conditions and the subsistence conditions of natural vegetation have changed to a considerable extent. According to the results, a warming and wetting tendency over the last two decades is obvious in the China’s coastal zone that are mainly due to land use changes as of growing urbanization, exhaust emissions from industries and transportations and, partly global climate change. Uncontrolled rapid development of the study area may be blamed for these negative changes as a major driving force. The positive feedback mechanisms between albedo, NDVI and climate factors also partly explain these changes. This study suggests that the method integrating biophysical parameters retrieved from remote sensed images and meteorologic data provides a novel and feasible way to monitor large scale eco-environmental changes.

  8. A Joint Approach to the Study of S-Type and P-Type Habitable Zones in Binary Systems: New Results in the View of 3-D Planetary Climate Models

    NASA Astrophysics Data System (ADS)

    Cuntz, Manfred

    2015-01-01

    In two previous papers, given by Cuntz (2014a,b) [ApJ 780, A14 (19 pages); arXiv:1409.3796], a comprehensive approach has been provided for the study of S-type and P-type habitable zones in stellar binary systems, P-type orbits occur when the planet orbits both binary components, whereas in case of S-type orbits, the planet orbits only one of the binary components with the second component considered a perturbator. The selected approach considers a variety of aspects, including (1) the consideration of a joint constraint including orbital stability and a habitable region for a possible system planet through the stellar radiative energy fluxes; (2) the treatment of conservative (CHZ), general (GHZ) and extended zones of habitability (EHZ) [see Paper I for definitions] for the systems as previously defined for the Solar System; (3) the provision of a combined formalism for the assessment of both S-type and P-type habitability; in particular, mathematical criteria are devised for which kind of system S-type and P-type habitability is realized; and (4) the applications of the theoretical approach to systems with the stars in different kinds of orbits, including elliptical orbits (the most expected case). Particularly, an algebraic formalism for the assessment of both S-type and P-type habitability is given based on a higher-order polynomial expression. Thus, an a prior specification for the presence or absence of S-type or P-type radiative habitable zones is - from a mathematical point of view - neither necessary nor possible, as those are determined by the adopted formalism. Previously, numerous applications of the method have been given encompassing theoretical star-panet systems and and observations. Most recently, this method has been upgraded to include recent studies of 3-D planetary climate models. Originally, this type of work affects the extent and position of habitable zones around single stars; however, it has also profound consequence for the habitable

  9. Effects of Climate Change on Stratification-Destratification Cycles and Resulting Cyanobacterial Blooms in Shallow Lakes of the North Temperate Zone

    NASA Astrophysics Data System (ADS)

    King, A. T.; Schaffner, L. R.; Gilman, B.; Gronwall, T. R.; Gronwall, D.; Dietz, E. R.; Hairston, N., Jr.

    2016-12-01

    "Harmful Algal Blooms" of cyanobacteria (cyanoHABs) have become more frequent and larger in extent for inland waters across the globe. Honeoye Lake, the shallowest of the New York State Finger Lakes (9 m max depth, 7 km long), has experienced recent problematic blooms. We use this lake as a model system for understanding the effects of climate change on cyanoHABs in shallow lakes. Cyanobacteria thrive in warm waters with high phosphorus concentrations. While high P is often caused by external nutrient loading via surface runoff, it can also result from internal loading when P-rich sediment is exposed to anoxic/reducing conditions in a lake's hypolimnion after prolonged stratification. In deep lakes, hypolimnetic water remains isolated from the epilimnion throughout the summer with the dissolved P separated from illuminated surface water; in very shallow lakes where the entire water column remains oxygenated/oxidizing, P is bound in insoluble inorganic complexes. However, in lakes of intermediate depth, hypolimnetic water high in soluble reactive P may mix into the photic zone if sufficiently strong winds occur, stimulating a cyanoHAB. We suggest that repeated cycles of stratification, hypolimnetic anoxia, and subsequent mixing may result in "phosphorus pumping" with recurrent cyanoHABs throughout summer. Climate change is causing stronger thermal stratification in lakes through increased surface warming but also causing more frequent storms that can break down stratification in a shallow lake. We use Honeoye Lake as a model system for understanding the extent to which P-pumping occurs and the likely effects of climate change on cyanoHABs. Field data collected in summer 2016 were used to calibrate the publically available General Lake Model (GLM) to predict Honeoye's discontinuous polymictic pattern of stratification punctuated by overturn events and spikes in epilimnetic P and cyanobacterial biomass. We use the calibrated model to determine cyanoHAB incidence as a

  10. Evaluating controls of soil properties and climatic conditions on the use of an exponential filter for converting near surface to root zone soil moisture contents

    NASA Astrophysics Data System (ADS)

    Wang, Tiejun; Franz, Trenton E.; You, Jinsheng; Shulski, Martha D.; Ray, Chittaranjan

    2017-05-01

    Root zone soil moisture (RZSM) is an important state variable for understanding various land surface and ecohydrological processes. Due to the lack of field measurements, different methods have been proposed to estimate RZSM, including the use of exponential filters to predict RZSM from remotely sensed near surface soil moisture data. However, inconsistent findings about the controls on the optimal characteristic time length Topt, which is used in the exponential filter method, have been reported in the literature. To reconcile these inconsistent findings and further improve the use of the method, the impacts of soil properties and climatic conditions on Topt were assessed in this study using observed and modelled soil moisture datasets. Daily soil moisture data, daily meteorological records, and soil properties were retrieved from the Automated Weather Data Network (AWDN) and the Soil Climate Analysis Network (SCAN) within the continental United States. Data from the AWDN stations showed that Topt was mostly controlled by soil texture (e.g., a negative correlation with the sand fraction and a positive one with the clay fraction) as compared to climatic conditions. However, at SCAN stations, Topt was mostly affected by precipitation (P), and no significant correlation was found between Topt and soil texture. The difference in controlling factors between ADWN and SCAN stations can be largely attributed to the higher spatial variability in P across the SCAN stations, which overrode the impacts of soil properties on Topt. A 1-D vadose zone model was also utilized to simulate soil moisture at selected SCAN sites using a generated soil hydraulic parameter dataset. The simulation results further demonstrated the negative relationship between Topt and P observed for the SCAN stations. Moreover, the simulation results revealed that Topt was larger under vegetated conditions than under bare surface conditions. Under the same climatic conditions at each simulated site, which

  11. Climatic and topographic controls on the style and timing of Late Quaternary glaciation throughout Tibet and the Himalaya defined by 10Be cosmogenic radionuclide surface exposure dating

    USGS Publications Warehouse

    Owen, L.A.; Finkel, R.C.; Barnard, P.L.; Haizhou, Ma; Asahi, K.; Caffee, M.W.; Derbyshire, E.

    2005-01-01

    Temporal and spatial changes in glacier cover throughout the Late Quaternary in Tibet and the bordering mountains are poorly defined because of the inaccessibility and vastness of the region, and the lack of numerical dating. To help reconstruct the timing and extent of glaciation throughout Tibet and the bordering mountains, we use geomorphic mapping and 10Be cosmogenic radionuclide (CRN) surface dating in study areas in southeastern (Gonga Shan), southern (Karola Pass) and central (Western Nyainqentanggulha Shan and Tanggula Shan) Tibet, and we compare these with recently determined numerical chronologies in other parts of the plateau and its borderlands. Each of the study regions receives its precipitation mainly during the south Asian summer monsoon when it falls as snow at high altitudes. Gonga Shan receives the most precipitation (>2000 mm a-1) while, near the margins of monsoon influence, the Karola Pass receives moderate amounts of precipitation (500-600 mm a-1) and, in the interior of the plateau, little precipitation falls on the western Nyainqentanggulha Shan (???300 mm a -1) and the Tanggula Shan (400-700 mm a-1). The higher precipitation values for the Tanggula Shan are due to strong orographic effects. In each region, at least three sets of moraines and associated landforms are preserved, providing evidence for multiple glaciations. The 10Be CRN surface exposure dating shows that the formation of moraines in Gonga Shan occurred during the early-mid Holocene, Neoglacial and Little Ice Age, on the Karola Pass during the Lateglacial, Early Holocene and Neoglacial, in the Nyainqentanggulha Shan date during the early part of the last glacial cycle, global Last Glacial Maximum and Lateglacial, and on the Tanggula Shan during the penultimate glacial cycle and the early part of the last glacial cycle. The oldest moraine succession in each of these regions varies from the early Holocene (Gonga Shan), Lateglacial (Karola Pass), early Last Glacial (western

  12. Evolutionary refugia and ecological refuges: key concepts for conserving Australian arid zone freshwater biodiversity under climate change

    PubMed Central

    Davis, Jenny; Pavlova, Alexandra; Thompson, Ross; Sunnucks, Paul

    2013-01-01

    Refugia have been suggested as priority sites for conservation under climate change because of their ability to facilitate survival of biota under adverse conditions. Here, we review the likely role of refugial habitats in conserving freshwater biota in arid Australian aquatic systems where the major long-term climatic influence has been aridification. We introduce a conceptual model that characterizes evolutionary refugia and ecological refuges based on our review of the attributes of aquatic habitats and freshwater taxa (fishes and aquatic invertebrates) in arid Australia. We also identify methods of recognizing likely future refugia and approaches to assessing the vulnerability of arid-adapted freshwater biota to a warming and drying climate. Evolutionary refugia in arid areas are characterized as permanent, groundwater-dependent habitats (subterranean aquifers and springs) supporting vicariant relicts and short-range endemics. Ecological refuges can vary across space and time, depending on the dispersal abilities of aquatic taxa and the geographical proximity and hydrological connectivity of aquatic habitats. The most important are the perennial waterbodies (both groundwater and surface water fed) that support obligate aquatic organisms. These species will persist where suitable habitats are available and dispersal pathways are maintained. For very mobile species (invertebrates with an aerial dispersal phase) evolutionary refugia may also act as ecological refuges. Evolutionary refugia are likely future refugia because their water source (groundwater) is decoupled from local precipitation. However, their biota is extremely vulnerable to changes in local conditions because population extinction risks cannot be abated by the dispersal of individuals from other sites. Conservation planning must incorporate a high level of protection for aquifers that support refugial sites. Ecological refuges are vulnerable to changes in regional climate because they have little

  13. Evolutionary refugia and ecological refuges: key concepts for conserving Australian arid zone freshwater biodiversity under climate change.

    PubMed

    Davis, Jenny; Pavlova, Alexandra; Thompson, Ross; Sunnucks, Paul

    2013-07-01

    Refugia have been suggested as priority sites for conservation under climate change because of their ability to facilitate survival of biota under adverse conditions. Here, we review the likely role of refugial habitats in conserving freshwater biota in arid Australian aquatic systems where the major long-term climatic influence has been aridification. We introduce a conceptual model that characterizes evolutionary refugia and ecological refugees based on our review of the attributes of aquatic habitats and freshwater taxa (fishes and aquatic invertebrates) in arid Australia. We also identify methods of recognizing likely future refugia and approaches to assessing the vulnerability of arid-adapted freshwater biota to a warming and drying climate. Evolutionary refugia in arid areas are characterized as permanent, groundwater-dependent habitats (subterranean aquifers and springs) supporting vicariant relicts and short-range endemics. Ecological refugees can vary across space and time, depending on the dispersal abilities of aquatic taxa and the geographical proximity and hydrological connectivity of aquatic habitats. The most important are the perennial waterbodies (both groundwater and surface water fed) that support obligate aquatic organisms. These species will persist where suitable habitats are available and dispersal pathways are maintained. For very mobile species (invertebrates with an aerial dispersal phase) evolutionary refugia may also act as ecological refugees. Evolutionary refugia are likely future refugia because their water source (groundwater) is decoupled from local precipitation. However, their biota is extremely vulnerable to changes in local conditions because population extinction risks cannot be abated by the dispersal of individuals from other sites. Conservation planning must incorporate a high level of protection for aquifers that support refugial sites. Ecological refuges are vulnerable to changes in regional climate because they have

  14. Groundwater recharge variation under climatic variability in Ajlun area and the recharge zone of Wadi Arab well field - Jordan

    NASA Astrophysics Data System (ADS)

    Raggad, Marwan Al; Alqadi, Mohammad; Magri, Fabien; Disse, Markus; Chiogna, Gabriele

    2017-04-01

    Pumping of 75 MCM/yr from Ajlun area and Wadi Arab well field has led to diminished groundwater levels in North Jordan and dramatically affects ecosystem services. Climate change compounds these issues by reducing recharge and increasing the ecosystem's hydrological demand. This paper investigates groundwater recharge response to climatic changes in North Jordan by modeling climatic parameters for the time frame 2015 - 2050. Water budget components were modeled through the J2000 hydrological model considering a groundwater recharge of 47 MCM/yr. Statistical downscaling of global circulation models indicated a decline in precipitation of around 30% by the year 2050 with 2.5 and 2 °C increases in maximum and minimum temperature, respectively. Recharge for the year 2050 was recalculated based on the downscaling results to be 27% less than current recharge. Continuous over-pumping with recharge reduction will cause a 30-70% reduction in saturated thickness by the same year. Modeling groundwater resilience under the new conditions showed a severe impact on the study area especially in the central parts which are expected to comprise a semi dry aquifer by 2050.

  15. Hydrocephalus Defined

    MedlinePlus

    ... narrow pathways. CSF is in constant production and absorption; it has a defined pathway from the lateral ... there is an imbalance of production and/or absorption. With most types of hydrocephalus, the fluid gets ...

  16. Influence of climate variability on water partitioning and effective energy and mass transfer (EEMT) in a semi-arid critical zone

    NASA Astrophysics Data System (ADS)

    Zapata-Rios, X.; Brooks, P. D.; Troch, P. A.; McIntosh, J.; Rasmussen, C.

    2015-08-01

    The Critical Zone (CZ) is the heterogeneous, near-surface layer of the planet that regulates life-sustaining resources. Previous research has demonstrated that a quantification of the influxes of effective energy and mass (EEMT) to the CZ can predict its structure and function. In this study, we quantify how climate variability in the last three decades (1984-2012) has affected water availability and the temporal trends in EEMT. This study takes place in the 1200 km2 upper Jemez River Basin in northern New Mexico. The analysis of climate, water availability, and EEMT was based on records from two high elevation SNOTEL stations, PRISM data, catchment scale discharge, and satellite derived net primary productivity (MODIS). Records from the two SNOTEL stations showed clear increasing trends in winter and annual temperatures (+1.0-1.3 °C decade-1; +1.2-1.4 °C decade-1, respectively), decreasing trends in winter and annual precipitation (-41.6-51.4 mm decade-1; -69.8-73.2 mm decade-1, respectively) and maximum Snow Water Equivalent (SWE; -33.1-34.7 mm decade-1). The water partitioning fluxes at the basin scale showed statistically significant decreasing trends in precipitation (-61.7 mm decade-1), discharge (-17.6 mm decade-1) and vaporization (-45.7 mm decade-1). Similarly Q50, an indicator of snowmelt timing, is occurring 4.3 days decade-1 earlier. Results from this study indicated a decreasing trend in water availability, a reduction in forest productivity (4 g C m-2 per 10 mm of reduction in Precipitation) and EEMT (1.2-1.3 MJ m2 decade-1). These changes in EEMT point towards a hotter, drier and less productive ecosystem which may alter critical zone processes in high elevation semi-arid systems.

  17. Revisions of the Fish Invasiveness Screening Kit (FISK) for its application in warmer climatic zones, with particular reference to peninsular Florida.

    PubMed

    Lawson, Larry L; Hill, Jeffrey E; Vilizzi, Lorenzo; Hardin, Scott; Copp, Gordon H

    2013-08-01

    The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate-zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species.

  18. A Framework for Thinking about the Spatial Variability of Snow across Multiple Scales and Climate Zones (Invited)

    NASA Astrophysics Data System (ADS)

    Sturm, M.

    2010-12-01

    It is well known that snow on the ground (or on lake and sea ice) varies at a myriad of scales ranging from millimeters to hundreds of kilometers. Many studies have focused directly, or in part, on snow heterogeneity at one or more of these scales, but a consistent broad framework within which these studies can be placed has yet to be developed. Consequently, the overall approach to scaling issues and snow variability is disjoint and inefficient. Nevertheless, strong common threads unite these issues. At the finest scale within-layer variations always arise from vapor transport and snow metamorphism. Layer properties vary based on weather during deposition and following snowfall (winter history). At plot to landscape scales, micro and macro topography and vegetation interact with wind, solar irradience, melt water percolation, and gravity to produce lateral variations in depth and snow water equivalent. At the coarsest scales, synoptic and climate gradients produce facies changes in both layers and bulk snow cover characteristics that vary in predictable ways. Here a preliminary multi-scale framework for snow variations is suggested and its utility discussed. At the largest scale, the framework uses the snow climate classification as a first discriminator. These classes are divided into wind-affected vs. non-wind-affected snow. Landscape and local variations in topography are then superimposed on these coarser-scale variations. Because vegetation varies with both climate and topography, it correlates with, as well as drives variations snow property variations; it becomes the third discriminator. Using these discriminators, similarities in snow variations and critical inherent length scales of several types of snow covers are explored.

  19. Assessment of the influence of climate condition on a migration rate of the 90Sr in the unsaturated zone in the Kirov and Sverdlovsk Region, Russia

    NASA Astrophysics Data System (ADS)

    Kurinova, Natalia; Dediulina, Ekaterina

    2016-04-01

    In this research, the transport of 90Sr with unsaturated flow in the same geological section (0.5 m top soil, from 0.5 to 6.0 m sand) was taken under consideration in two regions: Kirov and Sverdlovsk Region, Russia. The modeling schematization assumed that the nuclide polluted top soil to the depth of 0.2 m and from this point are transported with infiltration of precipitation during 100 year. The modeling were conducted in Hydrus 1D. The climate classification based on the Budyko aridity index (Budyko 1958) was used to define climate differences between regions. According this classification climate in both are temperate continental but the biggest differences is in the wetting degree. The Kirov region has the aridity index about 0.70; there is overwatering conditions, which means that average annual precipitation exceeds the potential evapotranspiration. The Sverdlovsk region has the aridity index about 1.04; there is the optimal watering conditions. The results of modeling of the 90Sr migration process showed the transport dynamic dependence on wetting degree. At the end of the 100-year period, the 90Sr reached the depth of 1.3 m in Kirov region and 1.0 m in Sverdlovsk.

  20. Inter-model diversity of Arctic amplification caused by global warming and its relationship with the Inter-tropical Convergence Zone in CMIP5 climate models

    NASA Astrophysics Data System (ADS)

    Yim, Bo Young; Yeh, Sang-Wook; Kug, Jong-Seong

    2016-08-01

    Surface-based Arctic amplification (AA) has experienced a remarkable increase in recent decades. Therefore, it is important to understand how Arctic warming might change in response to global warming. By analyzing the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model dataset, we examine how AA correlates with changes in tropical Pacific precipitation in response to global warming. It is found that that the changes in the latitudinal position of the Inter-tropical Convergence Zone (ITCZ) are associated to the simulated AA strength in the CMIP5 climate models. Specifically, AA tends to be stronger (weaker) in models where the ITCZ shifts relatively more northward (southward). Further analysis indicates that the inter-model diversity of AA strength in the CMIP5 climate models is related to the changes in large-scale atmospheric circulation associated with the meridional shift of the ITCZ. These results emphasize a close relationship between AA and changes in tropical Pacific precipitation in response to global warming.

  1. Inter-model diversity of Arctic amplification caused by global warming and its relationship with the Inter-tropical Convergence Zone in CMIP5 climate models

    NASA Astrophysics Data System (ADS)

    Yim, Bo Young; Yeh, Sang-Wook; Kug, Jong-Seong

    2017-06-01

    Surface-based Arctic amplification (AA) has experienced a remarkable increase in recent decades. Therefore, it is important to understand how Arctic warming might change in response to global warming. By analyzing the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model dataset, we examine how AA correlates with changes in tropical Pacific precipitation in response to global warming. It is found that that the changes in the latitudinal position of the Inter-tropical Convergence Zone (ITCZ) are associated to the simulated AA strength in the CMIP5 climate models. Specifically, AA tends to be stronger (weaker) in models where the ITCZ shifts relatively more northward (southward). Further analysis indicates that the inter-model diversity of AA strength in the CMIP5 climate models is related to the changes in large-scale atmospheric circulation associated with the meridional shift of the ITCZ. These results emphasize a close relationship between AA and changes in tropical Pacific precipitation in response to global warming.

  2. Scale-dependent interactions between vegetation, landscape, and climate: How critical zone structure influences ecohydrological reslience in a rapidly changing world

    NASA Astrophysics Data System (ADS)

    Brooks, P. D.; Barnard, H. R.; Chorover, J.; Fan, Y.; Gallo, E. L.; Godsey, S.; Maxwell, R. M.; McNamara, J. P.; Swetnam, T. L.; Tague, N.

    2015-12-01

    Concurrent changes in climate, land cover, and population are pushing coupled human and natural systems outside of the historical range of natural variability, presenting major challenges to the management of natural and built environments worldwide. A comprehensive understanding of how precipitation is partitioned to ecosystem and societal water resources is central to many of these challenges. Although considerable progress has been made advancing process understanding and developing ecohydrological models, a key challenge remains applying this knowledge to landscape and regional scales of resource management. Approaches to address this challenge, ranging from deterministic to probabilistic models, all face the challenge of identifying scale breaks in the coupling between biotic and abiotic processes. We employ an alternative, complementary approach, combining newer observations (e.g. high resolution aerial LiDAR; isotopes) and established techniques to identify scale breaks and transitions in how ecological processes, occurring on relatively short timescales, are coupled to longer-term development of critical zone, that typically develops over longer time scales. At stand scales, vegetation structure strongly controls the fraction of precipitation partitioned to evaporation by influencing both solar radiation and turbulence with a net change in effective precipitation (water available for transpiration, recharge, or streamflow) of as much as 25%. At hillslope scales, topographic shading or exposure has similar magnitude effects on total evapotranspiration, while topographically driven water subsidy can double carbon storage through increases in both tree size and number. At catchment-scales, the coupling between vegetation, climate, and the physical landscape results in a predictable signature in hydrologic partitioning that reflects regional susceptibility to drought. Importantly, these transitions in biophysical interactions, occurring at scales from 0.01 to

  3. Spatiotemporal Patterns of Ice Mass Variations and the Local Climatic Factors in the Riparian Zone of Central Valley, California

    NASA Astrophysics Data System (ADS)

    Inamdar, P.; Ambinakudige, S.

    2016-12-01

    Californian icefields are natural basins of fresh water. They provide irrigation water to the farms in the central valley. We analyzed the ice mass loss rates, air temperature and land surface temperature (LST) in Sacramento and San Joaquin basins in California. The digital elevation models from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were used to calculate ice mass loss rate between the years 2002 and 2015. Additionally, Landsat TIR data were used to extract the land surface temperature. Data from local weather stations were analyzed to understand the spatiotemporal trends in air temperature. The results showed an overall mass recession of -0.8 ± 0.7 m w.e.a-1. We also noticed an about 60% loss in areal extent of the glaciers in the study basins between 2000 and 2015. Local climatic factors, along with the global climate patterns might have influenced the negative trends in the ice mass loss. Overall, there was an increase in the air temperature by 0.07± 0.02 °C in the central valley between 2000 and 2015. Furthermore, LST increased by 0.34 ± 0.4 °C and 0.55± 0.1 °C in the Sacramento and San Joaquin basins. Our preliminary results show the decrease in area and mass of ice mass in the basins, and changing agricultural practices in the valley.

  4. Cryolithic zone and Arctic shelf under conditions of climate changes as exemplified by the Kara Sea basin

    NASA Astrophysics Data System (ADS)

    Khodzher, T.

    2012-04-01

    In 2009-2011, a number of interdisciplinary surveys were carried out in the Lower Yenisei River, the Kara Sea shelf. Comprehensive analysis of the environmental state revealed no significant anthropogenic effect on atmosphere and water bodies in the Kara sector of the Arctic. Morphotype diversity of cysts of chrysophycean algae were for the first time studied in water and bottom sediments in the mixing zone of marine and river waters. A collection was composed from 100 strains of organotrophic psychrotolerant microorganisms with different level of activity. There was recorded a great variety of spore forming microorganisms of the genus Bacillus tolerant to extreme natural conditions. Distribution patterns of organic material were determined in the coastal-shelf zone of the Kara Sea. Shores composed of glacial complex contributed a large amount of organic carbon (2-3%) to the seas. Concentrations of organic carbon and nitrogen in sediments depended on type of sediments and sedimentation conditions. Concentration ratio Corg/Norg and isotopic ratio 13C/12C demonstrated that contribution of terrigenous component to organic matter of sediments decreased towards the open sea. Comprehensive survey of 7 thermokarst lakes (from 66.6° to 72.7° N) showed that these lakes are low-mineralised (30-80 mg/l) with high oxygen content (9-11 mgO/l). Degradation of permafrost for the past 170 years was reconstructed using results of analyses of chemical and biological composition of bottom sediments in thermokarst lakes. Degradation process of permafrost causing the formation of these lakes started in the 1930-60s. Beginning from the 1950s, this process accelerated followed by temperature maxima with the time lag of 5-7 years. These reconstructions of paleogeographic conditions of the past based on studies of thermokarst Arctic lakes appeared to be prospective and require further investigations. This work was supported by RAS Presidium, Programme No. 21, Project No. 21.7.

  5. Climate effects on volcanism: Influence of ice load variations on magma storage zones with application to Icelandic volcanoes.

    NASA Astrophysics Data System (ADS)

    Albino, F.; Pinel, V.; Sigmundsson, F.

    2011-12-01

    Correlations between deglaciation periods and eruptive activity in the past have been strongly suggested, especially in Iceland, where the end of the last glaciation was characterised by a large pulse in volcanic production. Present-day reduction in ice load on subglacial volcanoes due to global warming is modifying pressure conditions in magmatic systems with a potential to influence magma production as well as shallow storage. Here, we model stress induced by variation in surface loads and evaluate how the resulting pressure conditions can modulate magmatic activity. We focus on the effect on shallow storage zones and show that ice loading can modify their failure conditions in a manner that depends critically on ice retreat timing and spatial distribution, the shape and depth of magma chambers as well the compressibility of the magma. We study in particular two subglacial volcanoes in Iceland: the Katla volcano under the Mýrdalsjökull ice cap and Grímsvötn at the Vatnajökull ice cap. Numerical calculations have been carried out in axisymmetric geometry for elliptical magma chambers. An elastic model is first used to evaluate the effects of the annual load cycle, due to seasonal variation of ice mass, which indicates an annual modulation of failure conditions on magma chambers at subglacial volcanoes. Our model predicts that, in case of a spherical or horizontally elongated magma chamber, eruptions are more likely when the seasonal snow cover is smallest. This triggering effect is small, around few kPa, but appears consistent with the fact that all the nine last major historical eruptions of Katla volcano occurred in period from May - October when the annual snow load is minimum. Viscous effects are then introduced to evaluate the influence of long term ice thinning on the shallow magma storage zones.

  6. Climate change induced effects on the predisposition of forests of the water protection zone Wildalpen to disturbances by bark beetles

    NASA Astrophysics Data System (ADS)

    Baier, P.; Pennerstorfer, J.; Schopf, A.

    2012-04-01

    The provision of drinking water of high quality is a precious service of forests. Large-scale disturbances like forest fires, wind throws, pest outbreaks and subsequent clear cutting may lead to changes in hydrology (runoff as well as percolation). Furthermore, water quality can be negatively influenced by increased erosion, increased decomposition of litter and humus and leaching of nitrate. Large-scale epidemics of forest pests may induce forest decline at landscape scale with subsequent long-lasting negative effects on water quality. The European spruce bark beetle, Ips typographus (L.), is one of the most significant sources of mortality in mature spruce forest ecosystems in Eurasia. The objective of this study was to apply a complex predisposition assessment system for hazard rating and for the evaluation of climate change impacts for the water protection forests of the City of Vienna in Wildalpen. The following steps have been done to adapt/apply the bark beetle phenology model and the hazard rating system: -application, adaptation and validation of the bark beetle phenology model PHENIPS concerning start of dispersion, brood initiation, duration of development, beginning of sister broods, voltinism and hibernation - spatial/temporal modelling of the phenology and voltinism of I. typographus using past, present as well as projected climate data - application and validation of the stand- and site related long-term predisposition assessment system using forest stand/site data, annual damage reports and outputs of phenology modelling as data input - mapping of endangered areas and assessment of future susceptibility to infestations by I. typographus and other disturbing agents based on climate scenarios using GIS. The assessment of site- and stand-related predisposition revealed that the forest stands in Wildalpen are highly susceptible to bark beetle infestation. More than 65% of the stands were assigned to the predisposition classes high/very high. Only 10% of

  7. A Global Geographic Information System Data Base of Storm Occurrences and Other Climatic Phenomena Affecting Coastal Zones (1991) (NDP-035)

    DOE Data Explorer

    Birdwell, K. R.; Daniels, R. C.

    2012-01-01

    This NDP is unique in that it represents CDIAC's first offering of ARC/INFOTM export data files and equivalent flat ASCII data files that may be used by raster or vector geographic information systems (GISs). The data set contains 61 variables, including information on tropical storms, hurricanes, super typhoons, extratropical cyclogeneses, polar lows, cyclonicity, influence of winds in monsoon regions, and sea-ice concentrations. Increased availability of source data has made it possible to extend the area of these data variables to regional or global coverages. All data variables except five are referenced to 1° × 1° or 5° × 5° grid cells of latitude and longitude. These data help meet the demand for new and improved climatologies of storm events and may be used in climate research studies, including the verification of general circulation models and the calculation of storm-recurrence intervals.

  8. The Climate-Population Nexus in the East African Horn: Emerging Degradation Trends in Rangeland and Pastoral Livelihood Zones

    NASA Astrophysics Data System (ADS)

    Pricope, N. G.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.

    2014-12-01

    Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. We identify regions where significant rainfall decrease from 1979-2011 over the entire continent of Africa couples with significant human population density increase. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that widespread degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using two underutilized MODIS products, we observe significant changes in vegetation patterns and productivity over the last decade all across the East African Horn. We observe significant vegetation browning trends in areas experiencing drying precipitation trends in addition to increasing population pressures. We also found that the drying precipitation trends only partially statistically explain the vegetation browning trends, further indicating that other factors such as population pressures and land use changes are responsible for the observed declining vegetation health. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, indicating potential long-term degradation of rangelands on which approximately 10 million people depend. These findings have serious implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected

  9. Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

    PubMed

    Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

    2015-01-01

    Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha-1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration.

  10. School Climate.

    ERIC Educational Resources Information Center

    Lindelow, John; Mazzarella, Jo Ann

    Chapter 7 of a volume on school leadership, this chapter defines, describes, and suggests ways to improve climate at the school building level. After citing a number of definitions of school climate, the authors conclude that school climate is the feel an individual gets from experiences within a school system, or the global summation of the…

  11. School Climate.

    ERIC Educational Resources Information Center

    Ellis, Thomas I.

    1988-01-01

    This pamphlet reviews five recent research studies that focus on various key aspects of school climate, a popular metaphor that is difficult to define, measure, or manipulate. "The Search for School Climate: A Review of the Research," by Carolyn Anderson, surveys the full scope of school climate literature, concluding with a summary of…

  12. Observation-based 3-D view of aerosol radiative properties over Indian Continental Tropical Convergence Zone: implications to regional climate

    NASA Astrophysics Data System (ADS)

    Jai Devi, J.; Tripathi, S. N.; Gupta, Tarun; Singh, B. N.; Gopalakrishnan, V.; Dey, Sagnik

    2011-11-01

    Spatial and vertical distributions of aerosol radiative properties over Indian Continental Tropical Convergence Zone (CTCZ) up to 6 km altitude during the pre-monsoon and monsoon seasons of 2008 have been measured and reported for the first time. Inter-seasonal and intra-seasonal comparisons of different aerosol properties below and above the boundary layer are carried out in and among different regions of CTCZ. During pre-monsoon, aerosol layers were found to be present up to altitude as high as 6 km over the Indo-Gangetic Plains and Himalayan foothills. A large increase in absorption coefficients (by two to five times) near the Himalayan foothills and coastal India than the background values may be attributed to extensive biomass burning as supported by fire counts data. During monsoon, the aerosols were mostly confined to lower troposphere. However, absorbing aerosols were found to rebuild much faster than scattering aerosols after rains. Heating rates were very high over urban city of Bareilly peaking around 2 km during the pre-monsoon. The HR values over urban Kanpur during monsoon were comparable to Bareilly during pre-monsoon. Negligible latitudinal gradient of heating rate from the Himalayan foothill to central India was observed during both the seasons.

  13. Dissipation and residues of difenoconazole and azoxystrobin in bananas and soil in two agro-climatic zones of China.

    PubMed

    Huan, Zhibo; Xu, Zhi; Lv, Daizhu; Xie, Defang; Luo, Jinhui

    2013-12-01

    Residues of a fungicide suspension (12 % difenoconazole, 18 % azoxystrobin) in bananas and soil were studied under tropical and subtropical monsoon climates, in Hainan and Yunnan provinces, respectively. The half-lives in bananas were shorter in Hainan (difenoconazole: 8.4-10.7 days; azoxystrobin: 7.8-8.4 days) than Yunnan (difenoconazole: 11.3-13.0 days; azoxystrobin: 10.4-11.6 days), possibly because of the higher temperatures and solar radiation levels in Hainan. The half-lives in soil were shorter in Yunnan (difenoconazole: 15.5-16.7; azoxystrobin: 11.9-13.9 days) than Hainan (difenoconazole: 23.1-23.2 days; azoxystrobin: 16.0-16.1 days), possibly because the organic carbon content was higher and rainfall lower in Yunnan than Hainan. Their physico-chemical properties suggest difenoconazole and azoxystrobin should be stable in bananas and soil, but both decreased to safe concentrations by the minimum harvest time after spraying the mixture at the recommended dosage and 1.5 times that dosage, through physical, chemical, and biological processes.

  14. Habitable zones around main sequence stars

    NASA Technical Reports Server (NTRS)

    Kasting, James F.; Whitmire, Daniel P.; Reynolds, Ray T.

    1993-01-01

    A mechanism for stabilizing climate on the earth and other earthlike planets is described, and the physical processes that define the inner and outer boundaries of the habitable zone (HZ) around the sun and main sequence stars are discussed. Physical constraints on the HZ obtained from Venus and Mars are taken into account. A 1D climate model is used to estimate the width of the HZ and the continuously habitable zone around the sun, and the analysis is extended to other main sequence stars. Whether other stars have planets and where such planets might be located with respect to the HZ is addressed. The implications of the findings for NASA's SETI project are considered.

  15. Habitable zones around main sequence stars

    NASA Technical Reports Server (NTRS)

    Kasting, James F.; Whitmire, Daniel P.; Reynolds, Ray T.

    1993-01-01

    A mechanism for stabilizing climate on the earth and other earthlike planets is described, and the physical processes that define the inner and outer boundaries of the habitable zone (HZ) around the sun and main sequence stars are discussed. Physical constraints on the HZ obtained from Venus and Mars are taken into account. A 1D climate model is used to estimate the width of the HZ and the continuously habitable zone around the sun, and the analysis is extended to other main sequence stars. Whether other stars have planets and where such planets might be located with respect to the HZ is addressed. The implications of the findings for NASA's SETI project are considered.

  16. Impacts of extensive driftnet fishery and late 1990s climate regime shift on dominant epipelagic nekton in the Transition Region and Subtropical Frontal Zone: Implications for fishery management

    NASA Astrophysics Data System (ADS)

    Ichii, T.; Nishikawa, H.; Igarashi, H.; Okamura, H.; Mahapatra, K.; Sakai, M.; Wakabayashi, T.; Inagake, D.; Okada, Y.

    2017-01-01

    We investigated the impacts of extensive anthropogenic (high seas driftnet squid fishery) and natural (late 1990s major climate regime shift) events on dominant epipelagic fish, squid, and shark in the central North Pacific Transition Region based on a driftnet survey covering the years 1979-2006. Fishing was conducted by Japan, Korea and Taiwan to target neon flying squid in the period 1979-1992, resulting in a decline in stocks of the target species and non-target species (Pacific pomfret and juvenile blue shark), which were by-catch of this fishery. The catch was found to be at the maximum sustainable yield (MSY) level for neon flying squid, the underfished level for juvenile blue shark, but the overfished level for Pacific pomfret. The MSY of Pacific pomfret indicated that this species is more susceptible to exploitation than previously considered. In response to the late 1990s regime shift, neon flying squid and Pacific saury showed low stock levels in 1999-2002 and 1998-2002, respectively, as a result of reduced productivity in their nursery grounds (the Subtropical Frontal Zone and Kuroshio Extension Bifurcation Region, respectively). On the other hand, Pacific pomfret showed no decreasing trend in stock during the low- and intermediate-productivity regimes because of the high productivity of their main spawning/nursery ground (Transition Zone Chlorophyll Front), which was independent of the regime shifts. Thus, squid and saury appear to be more susceptible to the regime shift than pomfret. We discuss the implications for stock management of the species-specific responses to the fishery and the regime shift.

  17. Application of a 3D Model to Assess the Thermo-Hydrological Effects of Climate Warming in a Discontinuous Permafrost Zone, Umiujaq, Northern Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Parhizkar, M.; Therrien, R.; Molson, J. W. H.; Lemieux, J. M.; Fortier, R.; Talbot Poulin, M. C.; Therrien, P.; Ouellet, M.

    2016-12-01

    The rate of permafrost degradation in northern Quebec, Canada, has increased over the last two decades due to climate warming, which is expected to significantly modify the hydrogeologic and thermal regimes. Groundwater accessibility is also expected to increase and could become a significant source of drinking water for northern communities. In this project, an integrated surface water / groundwater flow model, HydroGeoSphere, is being applied to a 2 km2catchment in northern Quebec to assess the effect of future climate change on thermo-hydrological conditions as well as on changes in groundwater availability for northern communities. The catchment is located in a discontinuous but widespread permafrost zone near Umiujaq (northern Quebec, Canada) where the subsurface consists of a 10-30 m-thick coarse-grained glaciofluvial layer forming a good aquifer beneath a permafrost-rich silty marine unit. A conceptual thermo-hydrological model of the catchment has been built from field data collected over 5 years, including hydraulic heads, stream flow rates, subsurface geology, as well as ground temperatures and thermal fluxes around two 10-20 m-thick permafrost mounds. The integrated 3D numerical model includes variably-saturated groundwater flow with transient recharge, as well as advective-conductive heat transport driven by transient air temperatures (varying from about -40 to +30 ºC) and a geothermal heat flux of 60 mW/m2. The model is calibrated to observed heads and temperatures by coupling PEST with HydroGeoSphere, allowing changes in hydraulic and thermal conductivities. Preliminary results are consistent with the available observed data, however non-uniqueness remains an important issue. The simulations are providing useful predictions of the permafrost thaw rate and associated changes to the hydrogeological flow system, including increased aquifer recharge following permafrost thaw.

  18. Will changes in root-zone temperature in boreal spring affect recovery of photosynthesis in Picea mariana and Populus tremuloides in a future climate?

    PubMed

    Fréchette, Emmanuelle; Ensminger, Ingo; Bergeron, Yves; Gessler, Arthur; Berninger, Frank

    2011-11-01

    Future climate will alter the soil cover of mosses and snow depths in the boreal forests of eastern Canada. In field manipulation experiments, we assessed the effects of varying moss and snow depths on the physiology of black spruce (Picea -mariana (Mill.) B.S.P.) and trembling aspen (Populus tremuloides Michx.) in the boreal black spruce forest of western Québec. For 1 year, naturally regenerated 10-year-old spruce and aspen were grown with one of the following treatments: additional N fertilization, addition of sphagnum moss cover, removal of mosses, delayed soil thawing through snow and hay addition, or accelerated soil thawing through springtime snow removal. Treatments that involved the addition of insulating moss or snow in the spring caused lower soil temperature, while removing moss and snow in the spring caused elevated soil temperature and thus had a warming effect. Soil warming treatments were associated with greater temperature variability. Additional soil cover, whether moss or snow, increased the rate of photosynthetic recovery in the spring. Moss and snow removal, on the other hand, had the opposite effect and lowered photosynthetic activity, especially in spruce. Maximal electron transport rate (ETR(max)) was, for spruce, 39.5% lower after moss removal than with moss addition, and 16.3% lower with accelerated thawing than with delayed thawing. Impaired photosynthetic recovery in the absence of insulating moss or snow covers was associated with lower foliar N concentrations. Both species were affected in that way, but trembling aspen generally reacted less strongly to all treatments. Our results indicate that a clear negative response of black spruce to changes in root-zone temperature should be anticipated in a future climate. Reduced moss cover and snow depth could adversely affect the photosynthetic capacities of black spruce, while having only minor effects on trembling aspen.

  19. Response of Glacier and Lake Dynamics in Four Inland Basins to Climate Change at the Transition Zone between the Karakorum And Himalayas

    PubMed Central

    Li, Zhiguo; Fan, Kuangsheng; Tian, Lide; Shi, Benlin; Zhang, Shuhong; Zhang, Jingjing

    2015-01-01

    Inland glacier and lake dynamics on the Tibetan Plateau (TP) and its surroundings over recent decades are good indicators of climate change and have a significant impact on the local water supply and ecosystem. The glacier and lake changes in Karakoram are quite different from those of the Himalayas. The mechanisms of the complex and regionally heterogeneous behavior of the glacier and lake changes between the Karakorum and Himalayas are poorly understood. Based on satellite images and meteorological data of Shiquanhe, Hetian, and Yutian stations, we demonstrate that the overall retreat of glaciers and increase of lake area at the transition zone between the Karakoram and Himalayas (TKH) have occurred since 1968 in response to a significant global climate change. Glacial areas in the Songmuxi Co basin, Zepu Co basin, Mang Co basin and Unnamed Co decreased by -1.98 ± 0.02 km2, -5.39 ± 0.02 km2, -0.01 ± 0.02 km2, and -0.12 ± 0.02 km2 during the study period, corresponding to losses of -1.42%, -2.86%, -1.54%, and -1.57%, respectively. The lake area of the Songmuxi Co, Zepu Co, Mang Co and Unnamed Co increased by 7.57 ± 0.02 km2, 8.53 ± 0.02 km2, 1.35 ± 0.02 km2, and 0.53±0.02 km2, corresponding to growths of 30.22%, 7.55%, 11.39%, and 8.05%, respectively. Increases in temperature was the main reason for glacier retreat, whereas decreases in potential evapotranspiration of lakes, increases in precipitation, and increases in melt water from glaciers and frozen soil all contributed to lake area expansion. PMID:26699717

  20. Response of Glacier and Lake Dynamics in Four Inland Basins to Climate Change at the Transition Zone between the Karakorum And Himalayas.

    PubMed

    Li, Zhiguo; Fan, Kuangsheng; Tian, Lide; Shi, Benlin; Zhang, Shuhong; Zhang, Jingjing

    2015-01-01

    Inland glacier and lake dynamics on the Tibetan Plateau (TP) and its surroundings over recent decades are good indicators of climate change and have a significant impact on the local water supply and ecosystem. The glacier and lake changes in Karakoram are quite different from those of the Himalayas. The mechanisms of the complex and regionally heterogeneous behavior of the glacier and lake changes between the Karakorum and Himalayas are poorly understood. Based on satellite images and meteorological data of Shiquanhe, Hetian, and Yutian stations, we demonstrate that the overall retreat of glaciers and increase of lake area at the transition zone between the Karakoram and Himalayas (TKH) have occurred since 1968 in response to a significant global climate change. Glacial areas in the Songmuxi Co basin, Zepu Co basin, Mang Co basin and Unnamed Co decreased by -1.98 ± 0.02 km2, -5.39 ± 0.02 km2, -0.01 ± 0.02 km2, and -0.12 ± 0.02 km2 during the study period, corresponding to losses of -1.42%, -2.86%, -1.54%, and -1.57%, respectively. The lake area of the Songmuxi Co, Zepu Co, Mang Co and Unnamed Co increased by 7.57 ± 0.02 km2, 8.53 ± 0.02 km2, 1.35 ± 0.02 km2, and 0.53 ± 0.02 km2, corresponding to growths of 30.22%, 7.55%, 11.39%, and 8.05%, respectively. Increases in temperature was the main reason for glacier retreat, whereas decreases in potential evapotranspiration of lakes, increases in precipitation, and increases in melt water from glaciers and frozen soil all contributed to lake area expansion.

  1. Basal crevasses and suture zones in the Larsen C Ice Shelf, Antarctica: Implications for ice shelf stability in a warming climate

    NASA Astrophysics Data System (ADS)

    McGrath, Daniel J.

    Understanding ice shelf structure and processes is paramount to future predictions of sea level rise, as nearly 75% of the ice flux from the Antarctic Ice Sheet (AIS) passes through these gates. The breakup of an ice shelf removes the longitudinal back stress acting on the grounded inland ice and leads to flow acceleration, dynamic thinning and frontal retreat, processes that can be sustained for more than a decade. Increased ice discharge to the ocean contributes to global sea level rise. This dissertation investigates basal crevasses and suture zones, two key structural components of ice shelves, in order to understand how the structure of an ice shelf influences its stability in a warming climate. Ground penetrating radar, high-resolution satellite imagery and a variety of modeling approaches are utilized to assess these features on the Larsen C Ice Shelf but in a manner that considers their influence on ice shelf stability around the AIS. Basal crevasses are large-scale (~66% of ice thickness and ten's of kms in length) and abundant features that are significant structural weaknesses. The viscoplastic deformation of the ice shelf in response to the perturbed hydrostatic balance leads to the formation of both surface depressions and crevasses, hence weakening the ice shelf further. Basal crevasses increase the local ice-ocean interface by ~30%, thereby increasing basal roughness and altering ice-ocean interactions. Ice-shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form at the lateral bounds of meteoric inflows to ice shelves. The termination of a 25 km-long rift in the Churchill Peninsula suture zone is investigated and found to contain ~60 m of accreted marine ice. Steady-state basal melting/freezing rates are determined for the ice shelf and applied to a flowline model to examine the along-flow evolution of ice shelf structure. The thickening surface wedge of locally accumulated meteoric ice

  2. Defining chaos

    SciTech Connect

    Hunt, Brian R.; Ott, Edward

    2015-09-15

    In this paper, we propose, discuss, and illustrate a computationally feasible definition of chaos which can be applied very generally to situations that are commonly encountered, including attractors, repellers, and non-periodically forced systems. This definition is based on an entropy-like quantity, which we call “expansion entropy,” and we define chaos as occurring when this quantity is positive. We relate and compare expansion entropy to the well-known concept of topological entropy to which it is equivalent under appropriate conditions. We also present example illustrations, discuss computational implementations, and point out issues arising from attempts at giving definitions of chaos that are not entropy-based.

  3. Climatic effects of biogenic volatile organic compounds (BVOCs) emissions and associated feedbacks due to vegetation change in the boreal zone

    NASA Astrophysics Data System (ADS)

    Blichner, Sara Marie; Koren Berntsen, Terje; Stordal, Frode

    2017-04-01

    , these results are compared to simulations of a future climate (corresponding to 2xCO2-concentrations) both with present-day and shifted vegetation patterns.

  4. Land use and urban morphology parameters for Vienna required for initialisation of the urban canopy model TEB derived via the concept of "local climate zones"

    NASA Astrophysics Data System (ADS)

    Trimmel, Heidelinde; Weihs, Philipp; Oswald, Sandro M.; Masson, Valéry; Schoetter, Robert

    2017-04-01

    Urban settlements are generally known for their high fractions of impermeable surfaces, large heat capacity and low humidity compared to rural areas which results in the well known phenomena of urban heat islands. The urbanized areas are growing which can amplify the intensity and frequency of situations with heat stress. The distribution of the urban heat island is not uniform though, because the urban environment is highly diverse regarding its morphology as building heights, building contiguity and configuration of open spaces and trees vary, which cause changes in the aerodynamic resistance for heat transfers and drag coefficients for momentum. Furthermore cities are characterized by highly variable physical surface properties as albedo, emissivity, heat capacity and thermal conductivity. The distribution of the urban heat island is influenced by these morphological and physical parameters as well as the distribution of unsealed soil and vegetation. These aspects influence the urban climate on micro- and mesoscale. For larger Vienna high resolution vector and raster geodatasets were processed to derive land use surface fractions and building morphology parameters on block scale following the methodology of Cordeau (2016). A dataset of building age and typology was cross checked and extended using satellite visual and thermal bands and linked to a database joining building age and typology with typical physical building parameters obtained from different studies (Berger et al. 2012 and Amtmann M and Altmann-Mavaddat N (2014)) and the OIB (Österreichisches Institut für Bautechnik). Using dominant parameters obtained using this high resolution mainly ground based data sets (building height, built area fraction, unsealed fraction, sky view factor) a local climate zone classification was produced using an algorithm. The threshold values were chosen according to Stewart and Oke (2012). This approach is compared to results obtained with the methodology of Bechtel et

  5. Identification of landslide-prone zones in the geomorphically and climatically sensitive Mandakini valley, (central Himalaya), for disaster governance using the Weights of Evidence method

    NASA Astrophysics Data System (ADS)

    Poonam; Rana, Naresh; Champati ray, Parshant Kumar; Bisht, Pinkey; Bagri, Dhirendra Singh; Wasson, Robert James; Sundriyal, Yashpal

    2017-05-01

    The entire Himalayan region is prone to disasters, with many people being vulnerable to hydroclimatic threats such as extreme rainfall-driven floods, glacial lake outburst floods (GLOFs), landslide lake outburst floods (LLOFs), and landslides triggered by rainfall. Landslides and floods are related, as the former cause the lakes that burst, and floods can undercut slopes and cause landslides. During the past 200 years, landslides and floods caused by LLOFs in the Garhwal Himalaya have occurred in 1894, 1970, and 1978; but the most disastrous event, in terms of loss of life and economic impact, occurred in June 2013, which was a result of extreme rainfall in the Higher Himalaya and breaching of a moraine-dammed lake, very short-lived LLOFs, and rainfall-induced runoff and landslides. Outmigration from the area as a result of the 2013 event has caused anxiety about the future of the economy and also concerns about security of a state that has an international border. As a contribution to planning and reconstruction to secure the livelihoods of the local people and to entice migrants to return, this paper identifies zones in the Mandakini valley susceptible to landslides using a 'Weights of Evidence' approach. The roles of climate, geology, and geomorphology of the valley are also given attention to explain the reasons for the disastrous event of June 2013. The results of the research presented here may be an important input to disaster governance.

  6. The role of fire in the formation of soil organic matter in tropical and subtropical climatic zones

    NASA Astrophysics Data System (ADS)

    Velasco-Molina, Marta; Knicker, Heike

    2016-04-01

    In tropical and subtropical areas, natural and prescribed vegetation fires lead to a considerable input of charcoal into soils. Whereas it is well accepted that an immediate effect of charcoal input represents the enhancement of the aromaticity of the soil organic matter (SOM) in particular of the topsoils, our knowledge about the long-term impact of this material on the humification processes is still scarce. Analyzing the SOM along various profiles of soils in Southern, Central and Northern Brazil indicated an ubiquitous presence of pyrogenic organic matter (PyOM) down to the C horizons. Interestingly, in several soils lower charcoal contributions were found in the topsoils than in the deeper horizons. Solid-state 13C and 15N NMR revealed that this PyOM is highly carboxylated. Most tentatively, charcoal was efficiently oxidized and biodegraded at the surface turning it into a more humus-like substance. However, some of the degradation products must have been transported into deeper soil regions where they were selectively preserved. Possibly, the oxygen depletion in subsoils or the interaction of oxidized PyOM with the mineral phase have increased its biochemical recalcitrance resulting in a preferential degradation of SOM derived from fire-unaffected sources. Our data clearly show that frequent charcoal addition can have a higher long-term impact on SOM of deeper soil horizons than commonly assumed. It may even represent an essential factor for defining the properties of such subsoil. Considering further that oxidized charcoal residues may also leach into the aquifer, a further evaluation of the impact of such residues on the groundwater is urgently needed.

  7. Monitoring of thaw subsidence, lithalsa collapse and thermokarst pond aggradation due to climate warming in the discontinuous permafrost zone in Nunavik, Canada

    NASA Astrophysics Data System (ADS)

    Fortier, R.

    2009-12-01

    The maximum extent of lithalsas in the discontinuous permafrost zone in Nunavik, Canada, occurred during the Little Ice Age (LIA) but they are currently decaying in response to climate warming. According to surface temperature history inferred from the inversion of a deep temperature profile measured in permafrost on the Katinniq Plateau in Nunavik, the surface temperature for the reference period between 1961 and 1990 was warmer of 1 °C in comparison to the one at the end of the LIA. Over the last five decades of meteorological records available for the Inuit communities of Kuujjuarapik, Inukjuak and Kuujjuaq in Nunavik, a slight cooling trend of less than 1 °C was observed from 1955 to 1992 and then followed by a marked warming trend of about 3 °C from 1992 to 2002 relative to the reference period 1961-1990. Because the climate is the main driver of the permafrost dynamics, the lithalsa collapse and thermokarst pond aggradation are good indicators of the permafrost degradation. The lithalsas and thermokarst ponds look like heaved forms and ramparted depressions filled with water respectively. They can be easily mapped on aerial photographs. Using time-lapse aerial and satellite photographs collected in 1957, 1983 and 2005, the permafrost degradation was assessed for a study area close to the Inuit community of Umiujaq in Nunavik. The superficies occupied by lithalsas and thermokarst ponds in 1957 were respectively 18.8 and 1.1% of the survey area while they were 11.2 and 3.0% in 2005. The land occupation by permafrost decreased of 7.6% in 48 years while the one by thermokarst increased of 1.9%. The rate of permafrost degradation increased from 0.07%/year between 1957 and 1983 to 0.12%/year between 1983 and 2005. Thermokarst ponds were already present in 1957 and permafrost degradation was still in progress due to the climate warming of 1 °C since the end of the LIA. The lithalsas were not yet in equilibrium with the climate in 1957 and further permafrost

  8. Long-term erosion and exhumation rates across different climatic zones in the Indian NW-Himalaya

    NASA Astrophysics Data System (ADS)

    Deeken, A.; Hourigan, J. K.; Thiede, R. C.; Sobel, E. R.; Strecker, M. R.

    2009-12-01

    Concepts have been developed that explain the changeover from tectonically to erosionally controlled exhumation processes in the tectonic evolution of the Himalayan orogen. However, the degree to which climate-driven erosion controls the late Cenozoic development of the southern Himalayan front is still a matter of debate. The Himalaya forms an orographic barrier with strong gradients both perpendicular to and along strike of the orogen. Thus, quantifying whether or not precipitation, erosion, and deformation patterns are correlated over geologic time should provide important insights into the tectonic evolution of the orogen. To constrain spatial and temporal variations in erosion and along strike variations in the timing and magnitude of deformation in the NW-Himalaya, we are establishing a data set of multiple low-temperature thermochronometers. Together with previous published data, our new apatite fission track (AFT) and zircon (U-Th)/He ages (ZHe) ages will be integrated with 3D-thermo-kinematic modeling. On a first sampling campaign, we collected 40 bedrock samples from the hanging wall of the MCT along an approximately 100 km long, strike perpendicular transect across the High Himalaya of the Chamba/Zanskar region that is situated between the Kishtwar- and the Larji-Kulu-Rampur-Windows. It extends from the southern Himalayan front, that is characterised by concentrated monsoonal precipitation, to the arid interior of the orogen. We present ca. 33 new AFT and 30 new ZHe from 3 elevation transects, which span between 2400 m and 3600 m. Our data constrain the exhumation history of the Chamba/Zanskar region spanning from the Miocene until present. ZHe and AFT ages range between 6.3 and 18.1 Ma, and 1.7 and 9.3 Ma, respectively. Our new data reveal spatiotemporal variation in the exhumation between the frontal range and the more internal compartments of the High Himalaya. At the internal ranges to the north, ZHe ages (9.4-18.1 Ma) as well as AFT ages (3.8-9.3 Ma

  9. Vertical structure and pH as factors for chitinolytic and pectinolytic microbial community of soils and terrestrial ecosystems of different climatic zones

    NASA Astrophysics Data System (ADS)

    Lukacheva, Evgeniya; Natalia, Manucharova

    2016-04-01

    technique developed that is used to detect and localize the presence or absence of specific DNA sequences on chromosomes. pH as one of the factors which can have influence on degradation of biopolymers was studied for chitiolytic communities of different zones. And results were compared with direct studyings by method of "sowing" on a Petri dishes. Thus, we compared old classical methods with modern molecular studies. The difference between climatic zones was studied and the mathematical model was created. The mathematic model could be use in different aims, such as prognosis of microbial community composition and their classification.

  10. Final Technical Report for "High-resolution temporal variations in groundwater chemistry: Tracing the links between climate, hydrology, and element mobility in the vadose zone"

    SciTech Connect

    Jay L. Banner

    2002-04-23

    In spite of a developing emphasis on geochemical methods in studies of modern hydrologic systems, there have been few attempts to examine temporal fluctuations in groundwater chemistry and element mobility in the near-surface environment. Relatively little is known regarding how groundwaters evolve over 10 to 10,000 year scales, yet this knowledge provides a critical framework for understanding the links between climate and hydrology, the evolution of soils, and element migration in the vadose environment. Recent analytical advances allow U-series measurements to be applied to developing high-resolution chronologies of Pleistocene and Holocene carbonates. The potential of these new tools is examined through an analysis of two well-defined, active karst systems in (1) Barbados and (2) Texas. (1) The research effort on Barbados has developed methods of estimating recharge and inferring the spatial and seasonal distribution of recharge to the Pleistocene limestone aquifer on Barbados. A new method has been developed to estimate recharge based on oxygen isotope variations in rainwater and groundwater. Inter-annual recharge variations indicate that recharge is dependent on the distribution of rainfall throughout the year rather than total annual rainfall. Consequently, a year when rainfall occurs primarily during the peak wet season months (August through November) may have more recharge than a year when rainfall is more evenly distributed through the year. These results lay important groundwork for analysis of rainfall/recharge variations over different time scales based on isotopic records presently being constructed using Barbados speleothems from the same aquifer. (2) The chronology of speleothems (cave calcite deposits) from three caves across 130 kilometers in central Texas provides a 71,000-year record of temporal changes in hydrology and climate. Fifty-three ages were determined by mass spectrometric 238U - 230Th and 235U - 231Pa analyses. The accuracy of the

  11. How lithology and climate affect REE mobility and fractionation along a shale weathering transect of the Susquehanna Shale Hills Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Ma, L.; Jin, L.; Dere, A. L.; White, T.; Mathur, R.; Brantley, S. L.

    2012-12-01

    Shale weathering is an important process in global elemental cycles. Accompanied by the transformation of bedrock into regolith, many elements including rare earth elements (REE) are mobilized primarily by chemical weathering in the Critical Zone. Then, REE are subsequently transported from the vadose zone to streams, with eventual deposition in the oceans. REE have been identified as crucial and strategic natural resources; and discovery of new REE deposits will be facilitated by understanding global REE cycles. At present, the mechanisms and environmental factors controlling release, transport, and deposition of REE - the sources and sinks - at Earth's surface remain unclear. Here, we present a systematic study of soils, stream sediments, stream waters, soil water and bedrock in six small watersheds that are developed on shale bedrock in the eastern USA to constrain the mobility and fractionation of REE during early stages of chemical weathering. The selected watersheds are part of the shale transect established by the Susquehanna Shale Hills Observatory (SSHO) and are well suited to investigate weathering on shales of different compositions or within different climate regimes but on the same shale unit. Our REE study from SSHO, a small gray shale watershed in central Pennsylvania, shows that up to 65% of the REE (relative to parent bedrock) is depleted in the acidic and organic-rich soils due to chemical leaching. Both weathering soil profiles and natural waters show a preferential removal of middle REE (MREE: Sm to Dy) relative to light REE (La to Nd) and heavy REE (Ho to Lu) during shale weathering, due to preferential release of MREE from a phosphate phase (rhabdophane). Strong positive Ce anomalies observed in the regolith and stream sediments point to the fractionation and preferential precipitation of Ce as compared to other REE, in the generally oxidizing conditions of the surface environments. One watershed developed on the Marcellus black shale in

  12. Sediment Cd and Mo accumulation in the oxygen-minimum zone off western Baja California linked to global climate over the past 52 kyr

    USGS Publications Warehouse

    Dean, W.E.; Zheng, Yen; Ortiz, J.D.; VanGeen, A.

    2006-01-01

    Concentrations of organic carbon (orgC), cadmium (Cd), and molybdenum (Mo) were measured in two sediment cores raised from depths of 430 and 700 m within the oxygen-minimum zone (OMZ) off southern Baja California at a temporal resolution of e10.5 kyr over the past 52 kyr. These records are supplemented with diffuse spectral reflectance (DSR) measurements obtained on board ship soon after collection at a resolution of e10.05 kyr. In the core from 700 m depth, a component extracted from the DSR data and the three geochemical proxies generally vary in concert with each other and over a wide range (4-22% orgC; 1-40 mg/kg Cd; 5-120 mg/kg Mo). Intervals of increased orgC, Cd, and Mo accumulation generally correspond to warm periods recorded in the oxygen-isotopic composition of Greenland ice, with the exception of the Bolling/Allerod which is only weakly expressed off Baja California. Concentrations of the biogenic proxies are higher in the core from 430 m depth, but erratic sediment accumulation before 15 ka precludes dating of the older intervals that are laminated and contain elevated orgC, Cd, and Mo concentrations. The new data provide further evidence of an intimate teleconnection between global climate and the intensity of the OMZ and/or productivity along the western margin of North America. On the basis of a comparison with Cd and Mo records collected elsewhere in the region, we conclude that productivity may actually have varied off southern Baja California by no more than a factor of 2 over the past 52 kyr. Copyright 2006 by the American Geophysical Union.

  13. Specific CT 3D rendering of the treatment zone after Irreversible Electroporation (IRE) in a pig liver model: the “Chebyshev Center Concept” to define the maximum treatable tumor size

    PubMed Central

    2014-01-01

    Background Size and shape of the treatment zone after Irreversible electroporation (IRE) can be difficult to depict due to the use of multiple applicators with complex spatial configuration. Exact geometrical definition of the treatment zone, however, is mandatory for acute treatment control since incomplete tumor coverage results in limited oncological outcome. In this study, the “Chebyshev Center Concept” was introduced for CT 3d rendering to assess size and position of the maximum treatable tumor at a specific safety margin. Methods In seven pig livers, three different IRE protocols were applied to create treatment zones of different size and shape: Protocol 1 (n = 5 IREs), Protocol 2 (n = 5 IREs), and Protocol 3 (n = 5 IREs). Contrast-enhanced CT was used to assess the treatment zones. Technique A consisted of a semi-automated software prototype for CT 3d rendering with the “Chebyshev Center Concept” implemented (the “Chebyshev Center” is the center of the largest inscribed sphere within the treatment zone) with automated definition of parameters for size, shape and position. Technique B consisted of standard CT 3d analysis with manual definition of the same parameters but position. Results For Protocol 1 and 2, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were not significantly different between Technique A and B. For Protocol 3, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were significantly smaller for Technique A compared with Technique B (41.1 ± 13.1 mm versus 53.8 ± 1.1 mm and 39.0 ± 8.4 mm versus 53.8 ± 1.1 mm; p < 0.05 and p < 0.01). For Protocol 1, 2 and 3, sphericity of the treatment zone was significantly larger for Technique A compared with B. Conclusions Regarding size and shape of the treatment zone after IRE, CT 3d rendering with the “Chebyshev Center Concept” implemented provides

  14. Current Climate Variability & Change

    NASA Astrophysics Data System (ADS)

    Diem, J.; Criswell, B.; Elliott, W. C.

    2013-12-01

    Current Climate Variability & Change is the ninth among a suite of ten interconnected, sequential labs that address all 39 climate-literacy concepts in the U.S. Global Change Research Program's Climate Literacy: The Essential Principles of Climate Sciences. The labs are as follows: Solar Radiation & Seasons, Stratospheric Ozone, The Troposphere, The Carbon Cycle, Global Surface Temperature, Glacial-Interglacial Cycles, Temperature Changes over the Past Millennium, Climates & Ecosystems, Current Climate Variability & Change, and Future Climate Change. All are inquiry-based, on-line products designed in a way that enables students to construct their own knowledge of a topic. Questions representative of various levels of Webb's depth of knowledge are embedded in each lab. In addition to the embedded questions, each lab has three or four essential questions related to the driving questions for the lab suite. These essential questions are presented as statements at the beginning of the material to represent the lab objectives, and then are asked at the end as questions to function as a summative assessment. For example, the Current Climate Variability & Change is built around these essential questions: (1) What has happened to the global temperature at the Earth's surface, in the middle troposphere, and in the lower stratosphere over the past several decades?; (2) What is the most likely cause of the changes in global temperature over the past several decades and what evidence is there that this is the cause?; and (3) What have been some of the clearly defined effects of the change in global temperature on the atmosphere and other spheres of the Earth system? An introductory Prezi allows the instructor to assess students' prior knowledge in relation to these questions, while also providing 'hooks' to pique their interest related to the topic. The lab begins by presenting examples of and key differences between climate variability (e.g., Mt. Pinatubo eruption) and

  15. Projected shifts in Köppen climate zones over China and their temporal evolution in CMIP5 multi-model simulations

    NASA Astrophysics Data System (ADS)

    Chan, Duo; Wu, Qigang; Jiang, Guixiang; Dai, Xianglin

    2016-03-01

    Previous studies have examined the projected climate types in China by 2100. This study identified the emergence time of climate shifts at a 1◦ scale over China from 1990 to 2100 and investigated the temporal evolution of Köppen-Geiger climate classifications computed from CMIP5 multi-model outputs. Climate shifts were detected in transition regions (7%-8% of China's land area) by 2010, including rapid replacement of mixed forest (Dwb) by deciduous forest (Dwa) over Northeast China, strong shrinkage of alpine climate type (ET) on the Tibetan Plateau, weak northward expansion of subtropical winterdry climate (Cwa) over Southeast China, and contraction of oceanic climate (Cwb) in Southwest China. Under all future RCP (Representative Concentration Pathway) scenarios, the reduction of Dwb in Northeast China and ET on the Tibetan Plateau was projected to accelerate substantially during 2010-30, and half of the total area occupied by ET in 1990 was projected to be redistributed by 2040. Under the most severe scenario (RCP8.5), sub-polar continental winter dry climate over Northeast China would disappear by 2040-50, ET on the Tibetan Plateau would disappear by 2070, and the climate types in 35.9% and 50.8% of China's land area would change by 2050 and 2100, respectively. The results presented in this paper indicate imperative impacts of anthropogenic climate change on China's ecoregions in future decades.

  16. Soil production is faster on south-facing slopes in the Susquehanna/Shale Hills Critical Zone Observatory due to periglacial, vegetative, and climate factors (Invited)

    NASA Astrophysics Data System (ADS)

    Jin, L.; Eissenstat, D.; Lin, H.; Chabaux, F. J.; Ma, L.; Brantley, S. L.

    2010-12-01

    The Susquehanna/Shale Hills Critical Zone Observatory is a V-shaped first-order catchment, developed almost entirely on the Silurian Rose Hill shale. We have focused on this site to investigate the controls, mechanisms and rates of shale weathering and soil formation. The parent rock is comprised primarily of illite, quartz, chlorite and ankerite. Three weathering fronts were observed at different depths identified in the northern ridgetop: ankerite dissolution begins tens of meters below land surface; plagioclase feldspar begins to weather at about 5-6 meters; chlorite and illite dissolve in the soil profiles to form more stable vermiculite and kaolinite. Six soil profiles were characterized: ridge top, mid-slope and valley floor sites on south-facing (9o) and north-facing (12o) planar hillslopes. Particle size analyses revealed that the soil textures were different: silt loam on the S-facing slope and sandy loam on the N-facing slope. All 6 sites show depletion profiles of major elements due to dissolution of clay minerals and feldspar. However, compared to the soils from the N-facing slope, those from S-facing slope were less depleted. Also local variations in element chemistry were observed with depth on S-facing slope to be superimposed on a general depletion trend. U disequilibrium isotopes of the bulk soils as well as parent rock were measured and modeled to estimate the soil production rates. In spite of similar slope, soil was produced, eroded and transported out of the S-facing slope at a faster rate. We argue that periglacial activities broke up bedrock and promoted soil erosion especially on the S-facing slopes, as evidenced by finer soil texture and fractures inferred by zig-zag variations in the depletion profiles. As such, the residence time of soil particles is generally shorter on the S-facing slope, preventing minerals in soils from becoming extensively weathered. Duration for the clay dissolution reactions (kinetically slow) plays a primary role

  17. Dynamic Agroecological Zones for the Inland Pacific Northwest, USA

    NASA Astrophysics Data System (ADS)

    Huggins, D. R.; Rupp, R.; Gessler, P.; Pan, W.; Brown, D. J.; Machado, S.; Walden, V. P.; Eigenbrode, S.; Abatzoglou, J. T.

    2011-12-01

    Agroecological zones (AEZ's) have traditionally been defined by integrating multiple layers of biophysical (e.g. climate, soil, terrain) and occasionally socioeconomic data to create unique zones with specific ranges of land use constraints and potentials. Our approach to defining AEZ's assumes that current agricultural land uses have emerged as a consequence of biophysical and socioeconomic drivers. Therefore, we explore the concept that AEZ's can be derived from classifying the geographic distribution of current agricultural systems (e.g. the wheat-fallow cropping system zone) based on spatially geo-referenced annual cropland use data that is currently available through the National Agricultural Statistical Service (NASS). By defining AEZ's in this way, we expect to: (1) provide baseline information that geographically delineates the boundaries of current AEZ's and subzones and therefore the capacity to evaluate shifts in AEZ boundaries over time; (2) assess the biophysical (e.g. climate, soils, terrain) and socioeconomic factors (e.g. commodity prices) that are most useful for predicting and correctly classifying current AEZ's, subzones or future shifts in AEZ boundaries; (3) identify and develop AEZ-relevant climate mitigation and adaptation strategies; and (4) integrate biophysical and socioeconomic data sources to pursue a transdisciplinary examination of climate-driven AEZ futures. Achieving these goals will aid in realizing major objectives for a USDA National Institute of Food and Agriculture, Agriculture and Food Research Initiative, Cooperative Agricultural Project entitled "Regional Approaches to Climate Change (REACCH) for Pacific Northwest Agriculture". REACCH is a research, education and extension project under the leadership of the University of Idaho with significant collaboration from Washington State University, Oregon State University and the USDA Agricultural Research Service that is working towards increasing the capacity of Inland Pacific

  18. Projected Shifts in Köppen Climate Zones over China and Their Temporal Evolution in CMIP5 Multi-Model Simulations

    NASA Astrophysics Data System (ADS)

    Wu, Q.; Chan, D.; Jiang, G.; Dai, X.

    2014-12-01

    This study uses CMIP5 multi-model ensemble projections to calculate Köppen-Geiger climate classifications and changes in China from 1990 to 2100. The projected climate types would shift toward warmer climate types from current climate distribution, changes are characterized by pronounced retreat of alpine (ET) climate type on the Tibetan Plateau, disappearance of sub-polar continental winter dry (Dwc) over Northeast China, expansion of temperate (C-type) climate over eastern China. Projected climate shifts are time-dependent. Large climate shifts are already detected in transition regions (7.5% of total land area) around 2010, including rapid replacement of mixed forest (Dwb) by deciduous forest (Dwa) over Northeast China and strong shrinkage of ET on the Tibetan Plateau, weak northward expansion of subtropical winter-dry (Cwa) over eastern China and contract of oceanic climate (Cwb) in Southwest China. Reduction of Dwb in Northeast China and ET on the Tibetan Plateau accelerates substantially during 2010-2030 under all scenarios. Half of the total area occupied by ET in 1990 is projected to be redistributed by 2040. Under the RCP 8.5 scenario, Dwc over Northeast China disappears by 2040-2050, ET on the Tibetan Plateaus disappears by 2070, shift of subtropical humid (Cfa) climate to Cwa over large parts of southeastern China occurs after 2050 due to decreasing wintertime precipitation, and the coverage of C-type climate increases about 7.6% by 2090. Under the RCP2.6, 4.5, 6 and 8.5 emissions pathways, climate types in 22.8%, 39.0%, 46.4% and 52.6% of China's land area change by 2100, primarily following simulated warming changes.

  19. Safety Zones

    EPA Pesticide Factsheets

    These are established primarily to reduce the accidental spread of hazardous substances by workers or equipment from contaminated areas to clean areas. They include the exclusion (hot) zone, contamination reduction (warm) zone, and support (cold) zone.

  20. Efficacy of climate forcings

    NASA Astrophysics Data System (ADS)

    Hansen, J.; Sato, M.; Ruedy, R.; Nazarenko, L.; Lacis, A.; Schmidt, G. A.; Russell, G.; Aleinov, I.; Bauer, M.; Bauer, S.; Bell, N.; Cairns, B.; Canuto, V.; Chandler, M.; Cheng, Y.; Del Genio, A.; Faluvegi, G.; Fleming, E.; Friend, A.; Hall, T.; Jackman, C.; Kelley, M.; Kiang, N.; Koch, D.; Lean, J.; Lerner, J.; Lo, K.; Menon, S.; Miller, R.; Minnis, P.; Novakov, T.; Oinas, V.; Perlwitz, Ja.; Perlwitz, Ju.; Rind, D.; Romanou, A.; Shindell, D.; Stone, P.; Sun, S.; Tausnev, N.; Thresher, D.; Wielicki, B.; Wong, T.; Yao, M.; Zhang, S.

    2005-09-01

    We use a global climate model to compare the effectiveness of many climate forcing agents for producing climate change. We find a substantial range in the "efficacy" of different forcings, where the efficacy is the global temperature response per unit forcing relative to the response to CO2 forcing. Anthropogenic CH4 has efficacy ˜110%, which increases to ˜145% when its indirect effects on stratospheric H2O and tropospheric O3 are included, yielding an effective climate forcing of ˜0.8 W/m2 for the period 1750-2000 and making CH4 the largest anthropogenic climate forcing other than CO2. Black carbon (BC) aerosols from biomass burning have a calculated efficacy ˜58%, while fossil fuel BC has an efficacy ˜78%. Accounting for forcing efficacies and for indirect effects via snow albedo and cloud changes, we find that fossil fuel soot, defined as BC + OC (organic carbon), has a net positive forcing while biomass burning BC + OC has a negative forcing. We show that replacement of the traditional instantaneous and adjusted forcings, Fi and Fa, with an easily computed alternative, Fs, yields a better predictor of climate change, i.e., its efficacies are closer to unity. Fs is inferred from flux and temperature changes in a fixed-ocean model run. There is remarkable congruence in the spatial distribution of climate change, normalized to the same forcing Fs, for most climate forcing agents, suggesting that the global forcing has more relevance to regional climate change than may have been anticipated. Increasing greenhouse gases intensify the Hadley circulation in our model, increasing rainfall in the Intertropical Convergence Zone (ITCZ), Eastern United States, and East Asia, while intensifying dry conditions in the subtropics including the Southwest United States, the Mediterranean region, the Middle East, and an expanding Sahel. These features survive in model simulations that use all estimated forcings for the period 1880-2000. Responses to localized forcings, such

  1. The Critical Zone: A Necessary Framework for Understanding Surface Earth Processes

    NASA Astrophysics Data System (ADS)

    Dietrich, W. E.

    2016-12-01

    One definition of the critical zone is: the thin veneer of Earth that extends from the top of the vegetation to the base of weathered bedrock. With this definition we can envision the critical zone as a distinct entity with a well-defined top and a fairly well-defined bottom that is distributed across terrestrial earth landscapes. It is a zone of co-evolving processes and, importantly, much of this zone is well below the soil mantle (and commonly more than 10 times thicker than the soil). Weathering advance into fresh bedrock creates a hydrologically-conductive skin that mediates runoff and solute chemistry, stores water used by vegetation, releases water as baseflow to streams, influences soil production and hillslope evolution, and feeds gasses to the atmosphere. Especially in seasonally dry environments, rock moisture in the critical zone, i.e. moisture that is exchangeable and potentially mobile in the matrix and fractures of the bedrock, can be a significant source of water to plants and is a previously unrecognized large component of the water budget that matters to climate models. First observations on the systematic variation of the critical zone across hillslopes have led to four distinct theories representing four distinct processes for what controls the depth to fresh bedrock (and thus the thickness of this zone across a hillslope). These theories are motivating geophysical surveys, deep drilling, and other actions to parameterize and explore the power of these models. Studies at the NSF-supported Critical Zone Observatories have taught us that the critical zone is an entity and that enduring field studies reveal key processes. A challenge we now face is how to include this emerging understanding of the critical zone into models of reactive transport, hydrologic processes and water supply, critical zone structure, landscape evolution, and climate.

  2. The recent climatic change of subarctic zone recorded in core sediments of Lake Abashiri in the east part of Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Seto, K.; Katsuki, K.; Sonoda, T.; Kawajiri, T.; Watanabe, T.; Okazaki, Y.

    2012-12-01

    In the coastal area of the Sea of Okhotsk in the east part of Hokkaido located to for subarctic zone, many brackish-water lakes are distributed. Especially, the Okhotsk brackish-water lake group around Abashiri City is constituted by major lake in Japan such as Lake Abashiri, Lake Mokoto, Lake Tofutsu, and Lake Notoro. The each lake shows a different present environment and history. Therefore, the change that is common in those lakes seems to be the change concerning the climate. In this study, recent environment change in Abashiri region (after the Little Ice Age) is discussed by sedimentologic and geochemical high-resolution analysis of the sediment cores collected from the Lake Abashiri. The water column of Lake Abashiri has a distinct halocline around 5m depths, and is divided into oligohaline surface waters and polyhaline bottom water by its halocline. The bottom water in Lake Abashiri shows the euxinic conditions throughout the annual. Therefore, surface sediment of below water depth 5m shows the black organic mud with the lamination. The 10AB-5C core collected from Lake Abashiri shows the length of 332cm. This core is composed of muddy sediment with a distinct lamination through all horizons. The Ta-a tephra (AD 1739) and Ko-c2 tephra (AD 1694) are found at the horizon of 250 cm, and 291 cm, respectively. Sedimentation rate based on these ages was 0.92cm/yr between Ko-c2 tephra and Ta-a tephra, and was 0.91cm/yr between surface and Ta-a tephra. Lamina set of 44 was recognized between Ko-c2 tephra and Ta-a tephra. This is suggested that this set is annual lamina. In 10AB-5C core, total organic carbon (TOC) contents, total sulfur (TS) contents, and C / N ratios were revealed by CNS elemental analysis. And the content of major elements were revealed by XRF elemental analysis. The change of iron (Fe) content synchronized with that of TS content. However, in the peak of TS contents around the horizon of 60cm, the Fe content does not change enough. It is

  3. Ecological opportunity and the evolution of habitat preferences in an arid-zone bird: implications for speciation in a climate-modified landscape

    PubMed Central

    Norman, Janette A.; Christidis, Les

    2016-01-01

    Bioclimatic models are widely used to investigate the impacts of climate change on species distributions. Range shifts are expected to occur as species track their current climate niche yet the potential for exploitation of new ecological opportunities that may arise as ecosystems and communities remodel is rarely considered. Here we show that grasswrens of the Amytornis textilis-modestus complex responded to new ecological opportunities in Australia’s arid biome through shifts in habitat preference following the development of chenopod shrublands during the late Plio-Pleistocene. We find evidence of spatially explicit responses to climatically driven landscape changes including changes in niche width and patterns of population growth. Conservation of structural and functional aspects of the ancestral niche appear to have facilitated recent habitat shifts, while demographic responses to late Pleistocene climate change provide evidence for the greater resilience of populations inhabiting the recently evolved chenopod shrubland communities. Similar responses could occur under future climate change in species exposed to novel ecological conditions, or those already occupying spatially heterogeneous landscapes. Mechanistic models that consider structural and functional aspects of the niche along with regional hydro-dynamics may be better predictors of future climate responses in Australia’s arid biome than bioclimatic models alone. PMID:26787111

  4. Ecological opportunity and the evolution of habitat preferences in an arid-zone bird: implications for speciation in a climate-modified landscape.

    PubMed

    Norman, Janette A; Christidis, Les

    2016-01-20

    Bioclimatic models are widely used to investigate the impacts of climate change on species distributions. Range shifts are expected to occur as species track their current climate niche yet the potential for exploitation of new ecological opportunities that may arise as ecosystems and communities remodel is rarely considered. Here we show that grasswrens of the Amytornis textilis-modestus complex responded to new ecological opportunities in Australia's arid biome through shifts in habitat preference following the development of chenopod shrublands during the late Plio-Pleistocene. We find evidence of spatially explicit responses to climatically driven landscape changes including changes in niche width and patterns of population growth. Conservation of structural and functional aspects of the ancestral niche appear to have facilitated recent habitat shifts, while demographic responses to late Pleistocene climate change provide evidence for the greater resilience of populations inhabiting the recently evolved chenopod shrubland communities. Similar responses could occur under future climate change in species exposed to novel ecological conditions, or those already occupying spatially heterogeneous landscapes. Mechanistic models that consider structural and functional aspects of the niche along with regional hydro-dynamics may be better predictors of future climate responses in Australia's arid biome than bioclimatic models alone.

  5. Modelling vegetation water-use and groundwater recharge as affected by climate variability in an arid-zone Acacia savanna woodland

    NASA Astrophysics Data System (ADS)

    Chen, Chao; Eamus, Derek; Cleverly, James; Boulain, Nicolas; Cook, Peter; Zhang, Lu; Cheng, Lei; Yu, Qiang

    2014-11-01

    For efficient and sustainable utilisation of limited groundwater resources, improved understanding of how vegetation water-use responds to climate variation and the corresponding controls on recharge is essential. This study investigated these responses using a modelling approach. The biophysically based model WAVES was calibrated and validated with more than two years of field experimental data conducted in Mulga (Acacia aneura) in arid central Australia. The validated model was then applied to simulate vegetation growth (as changes in overstory and understory leaf area index; LAI), vegetation water-use and groundwater recharge using observed climate data for the period 1981-2012. Due to large inter-annual climatic variability, especially precipitation, simulated annual mean LAI ranged from 0.12 to 0.35 for the overstory and 0.07 to 0.21 for the understory. These variations in simulated LAI resulted in vegetation water-use varying greatly from year-to-year, from 64 to 601 mm pa. Simulated vegetation water-use also showed distinct seasonal patterns. Vegetation dynamics affected by climate variability exerted significant controls on simulated annual recharge, which was greatly reduced to 0-48 mm compared to that (58-672 mm) only affected by climate. Understanding how climate variability and land use/land cover change interactively impact on groundwater recharge significantly improves groundwater resources management in arid and semi-arid regions.

  6. Floristic zones and aeroallergen diversity.

    PubMed

    Weber, Richard W

    2003-08-01

    The interplay of geographic, geochemical, and meteorologic factors combines to define distinct floristic zones in North America. Latitude, elevation, Pacific or Atlantic Ocean influence, continental air mass influence, mountains, and hills are contributory geographic factors. Hardiness zones are defined by the nadir of temperature, which strongly affects the survival of individual plant species. There are 12 hardiness zones from the northernmost tundra to the tropics of Mexico. Although it is useful to consider the 10 major floristic zones, the hardiness zones cut across these zones and characterize subregions. A multiplicity of local terrain effects, such as soil porosity and acidity, and sun exposure also impact on plant growth. The ability of plant species, whether woody shrubs and trees, or herbaceous weeds and grasses, to adapt to conditions within the floristic zones determines their range. This article identifies the major aeroallergenic species and the regions in which they are most prevalent.

  7. Managing climate change refugia for climate adaptation

    Treesearch

    Toni Lyn Morelli; Christopher Daly; Solomon Z. Dobrowski; Deanna M. Dulen; Joseph L. Ebersole; Stephen T. Jackson; Jessica D. Lundquist; Connie Millar; Sean P. Maher; William B. Monahan; Koren R. Nydick; Kelly T. Redmond; Sarah C. Sawyer; Sarah Stock; Steven R. Beissinger

    2016-01-01

    Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that...

  8. Paleontological evidence for defining the Anthropocene

    NASA Astrophysics Data System (ADS)

    Barnosky, A. D.

    2012-12-01

    Paleontological criteria formed the basis for defining most of the geological eras, periods, epochs, and ages that are commonly recognized. By the same token, the Anthropocene can be defined by paleontological distinctiveness in accordance with commonly accepted biostratigraphic and biochronologic practice. Here I focus on the utility of defining the Anthropocene by the distinctive fossils (or potential fossils of the future) that have accumulated and are accumulating in the sedimentary record. I discuss what kinds of biostratrigraphic criteria would be of most use in recognizing the Anthropocene's base and temporal extent, including pros and cons of definitions based on range zones, interval zones, lineage zones, assemblage zones, and abundance zones, as well as implications for potential reference sections. Key paleontological criteria useful in formally defining the Anthropocene as a geological epoch include (1) anthropogenic trace fossils such as buildings, roads, plastics, etc; (2) abundance zones based on remains of domesticated species and humans; and (3) assemblage zones based on species transported around the globe by people. The magnitude of paleontologically-recognizable changes that have occurred since humans became the dominant species on Earth is at least as great as the paleontological differences that distinguish other Cenozoic epochs, and supports recognition of the Anthropocene as a formal stratigraphic unit.

  9. Zone lines

    Treesearch

    Kevin T. Smith

    2001-01-01

    Zone lines are narrow, usually dark markings formed in decaying wood. Zone lines are found most frequently in advanced white rot of hardwoods, although they occasionally are associated both with brown rot and with softwoods.

  10. Latitudinal Position and Trends of the Intertropical Convergence Zone (ITCZ) and its Relationship with Upwelling in the Southern Caribbean Sea and Global Climate Indices

    NASA Astrophysics Data System (ADS)

    Carlock, Brett Edmond

    The Intertropical Convergence Zone (ITCZ) is a feature that results from the ocean-atmosphere interactions in the tropics around the world. The ITCZ is characterized by surface wind convergence, tall storm clouds, and it forms a belt of high time-averaged precipitation around the globe. The ITCZ undergoes seasonal migrations between 5°S and 15°N roughly following the subsolar point on Earth with the seasons, with a mean annual position located slightly above the Equator, between 2° and 5°N. This study tested the hypothesis that there was a northward shift in the median position of the ITCZ in the first decade of the 2000's relative to the 1900's. This hypothesis has been posed in the literature given a weakening in the intensity of the Trade Winds observed in the southern Caribbean Sea during the first decade of the 2000's, with concomitant ecological impacts due to weakening in coastal wind-driven upwelling. The hypothesis was tested by analyzing variations in the monthly latitudinal position of the ITCZ over the Atlantic Ocean relative to the median position computed for the period 1987-2011. The position of the ITCZ was derived from satellite-derived ocean surface wind measurements collected from 1987 to 2011. A Mann-Kendall analysis and a Monte Carlo simulation were used to test for trends in the median cross-basin latitudinal position of the ITCZ. The study included an analysis of regional changes across the tropical central Atlantic (50°W to 15°W), the Western Atlantic (50°W to 30°W), and the Eastern Atlantic (30°W to 15°W) within the tropics. The results show a slight southward trend in the median position of the ITCZ over the central Atlantic and also in the Eastern Atlantic in the first decade of the 2000's relative to the 1990's. While this trend is barely significant, it is likely simply due to interannual variation in the average annual position of the ITCZ. The data were also examined for the timing and persistence of a double ITCZ in the

  11. An aridity index defined by precipitation and specific humidity

    NASA Astrophysics Data System (ADS)

    Sahin, Sinan

    2012-06-01

    SummaryThe United Nations Environmental Programme (UNEP), defined an aridity index (AI) by the ratio of the annual precipitation and potential evapotranspiration (PET) totals. In this work, specific humidity was used instead of PET and a new aridity index (Iq) has been defined using the ratio of annual precipitation totals and annual mean specific humidity (Sh). As shown in this study, Sh can be easily computed with very high accuracy (3.569% error rate) with mean temperature, relative humidity and local pressure which are most commonly and widely measured meteorological data. The single point correlation graph of Sh which shows the entrance of aridity through the South Eastern Anatolia Region into Turkey and the distribution of the aridity over Turkey explains the relationship with Sh and aridity. According to the common and different aspects of arid zones found with AI, Iq and Erinç aridity index (Im), Iq found to be applicable for monitoring climate change and distribution of arid zones.

  12. A Fiji multi-coral δ18O composite approach to obtaining a more accurate reconstruction of the last two-centuries of the ocean-climate variability in the South Pacific Convergence Zone region

    NASA Astrophysics Data System (ADS)

    Dassié, Emilie P.; Linsley, Braddock K.; Corrège, Thierry; Wu, Henry C.; Lemley, Gavin M.; Howe, Steve; Cabioch, Guy

    2014-12-01

    The limited availability of oceanographic data in the tropical Pacific Ocean prior to the satellite era makes coral-based climate reconstructions a key tool for extending the instrumental record back in time, thereby providing a much needed test for climate models and projections. We have generated a unique regional network consisting of five Porites coral δ18O time series from different locations in the Fijian archipelago. Our results indicate that using a minimum of three Porites coral δ18O records from Fiji is statistically sufficient to obtain a reliable signal for climate reconstruction, and that application of an approach used in tree ring studies is a suitable tool to determine this number. The coral δ18O composite indicates that while sea surface temperature (SST) variability is the primary driver of seasonal δ18O variability in these Fiji corals, annual average coral δ18O is more closely correlated to sea surface salinity (SSS) as previously reported. Our results highlight the importance of water mass advection in controlling Fiji coral δ18O and salinity variability at interannual and decadal time scales despite being located in the heavy rainfall region of the South Pacific Convergence Zone (SPCZ). The Fiji δ18O composite presents a secular freshening and warming trend since the 1850s coupled with changes in both interannual (IA) and decadal/interdecadal (D/I) variance. The changes in IA and D/I variance suggest a re-organization of climatic variability in the SPCZ region beginning in the late 1800s to period of a more dominant interannual variability, which could correspond to a southeast expansion of the SPCZ.

  13. Air Source Cold Climate Heat Pump

    DTIC Science & Technology

    2013-08-01

    The buildings were modified so that one zone used the cold climate heat pump and the other zone used its original modern central HVAC system . Both...been updated with insulation, a sheet metal roof, and a modern central HVAC system . Both buildings had two zones for heating and cooling, which...climate heat pump and the other zone used its original modern central HVAC system . Both zones were instrumented so that energy consumption and

  14. Advances in rainfall-runoff estimation using the NRCS-CN model in a changing climate in semiarid zones in both the northern and southern hemispheres

    NASA Astrophysics Data System (ADS)

    Durán-Barroso, Pablo; João Simas Guerreiro, Maria; De Andrade, Eunice Maia; González, Javier

    2016-04-01

    Extreme events runoff is one of the most important variables in water resources management, but its quantification in semiarid watersheds is not easy, especially because of their large retention capacity. In the worldwide used NRCS Curve Number model (CN), retention capacity is conditioned by the initial abstraction parameter, for which this manuscript questions its assessment procedure. We propose a more accurate procedure to compute the initial abstractions based on previous cumulative dry days (CDD). We also analyze the combined effect of initial abstractions and climatic characteristics by analyzing CN in a dry (Walnut Gulch, US) and wet (Ceará, Brazil) semiarid environment. With this new methodology and the evolution of rainfall volumes and CDD analysis, it is possible to suggest consequences of climate change on floods forecast of extreme rainfall-runoff events in a semiarid environment.

  15. The origin of grasslands in the temperate forest zone of east-central Europe: long-term legacy of climate and human impact

    PubMed Central

    Kuneš, Petr; Svobodová-Svitavská, Helena; Kolář, Jan; Hajnalová, Mária; Abraham, Vojtěch; Macek, Martin; Tkáč, Peter; Szabó, Péter

    2017-01-01

    The post-glacial fate of central European grasslands has stimulated palaeoecological debates for a century. Some argued for the continuous survival of open land, while others claimed that closed forest had developed during the Middle Holocene. The reasons behind stability or changes in the proportion of open land are also unclear. We aim to reconstruct regional vegetation openness and test the effects of climate and human impact on vegetation change throughout the Holocene. We present a newly dated pollen record from north-western fringes of the Pannonian Plain, east-central Europe, and reconstruct Holocene regional vegetation development by the REVEALS model for 27 pollen-equivalent taxa. Estimated vegetation is correlated in the same area with a human activity model based on all available archaeological information and a macrophysical climate model. The palaeovegetation record indicates the continuous presence of open land throughout the Holocene. Grasslands and open woodlands were probably maintained by local arid climatic conditions during the early Holocene delaying the spread of deciduous (oak) forests. Significantly detectable human-made landscape transformation started only after 2000 BC. Our analyses suggest that Neolithic people spread into a landscape that was already open. Humans probably contributed to the spread of oak, and influenced the dynamics of hazel and hornbeam. PMID:28522887

  16. The origin of grasslands in the temperate forest zone of east-central Europe: long-term legacy of climate and human impact.

    PubMed

    Kuneš, Petr; Svobodová-Svitavská, Helena; Kolář, Jan; Hajnalová, Mária; Abraham, Vojtěch; Macek, Martin; Tkáč, Peter; Szabó, Péter

    2015-05-15

    The post-glacial fate of central European grasslands has stimulated palaeoecological debates for a century. Some argued for the continuous survival of open land, while others claimed that closed forest had developed during the Middle Holocene. The reasons behind stability or changes in the proportion of open land are also unclear. We aim to reconstruct regional vegetation openness and test the effects of climate and human impact on vegetation change throughout the Holocene. We present a newly dated pollen record from north-western fringes of the Pannonian Plain, east-central Europe, and reconstruct Holocene regional vegetation development by the REVEALS model for 27 pollen-equivalent taxa. Estimated vegetation is correlated in the same area with a human activity model based on all available archaeological information and a macrophysical climate model. The palaeovegetation record indicates the continuous presence of open land throughout the Holocene. Grasslands and open woodlands were probably maintained by local arid climatic conditions during the early Holocene delaying the spread of deciduous (oak) forests. Significantly detectable human-made landscape transformation started only after 2000 BC. Our analyses suggest that Neolithic people spread into a landscape that was already open. Humans probably contributed to the spread of oak, and influenced the dynamics of hazel and hornbeam.

  17. The origin of grasslands in the temperate forest zone of east-central Europe: long-term legacy of climate and human impact

    NASA Astrophysics Data System (ADS)

    Kuneš, Petr; Svobodová-Svitavská, Helena; Kolář, Jan; Hajnalová, Mária; Abraham, Vojtěch; Macek, Martin; Tkáč, Peter; Szabó, Péter

    2015-05-01

    The post-glacial fate of central European grasslands has stimulated palaeoecological debates for a century. Some argued for the continuous survival of open land, while others claimed that closed forest had developed during the Middle Holocene. The reasons behind stability or changes in the proportion of open land are also unclear. We aim to reconstruct regional vegetation openness and test the effects of climate and human impact on vegetation change throughout the Holocene. We present a newly dated pollen record from north-western fringes of the Pannonian Plain, east-central Europe, and reconstruct Holocene regional vegetation development by the REVEALS model for 27 pollen-equivalent taxa. Estimated vegetation is correlated in the same area with a human activity model based on all available archaeological information and a macrophysical climate model. The palaeovegetation record indicates the continuous presence of open land throughout the Holocene. Grasslands and open woodlands were probably maintained by local arid climatic conditions during the early Holocene delaying the spread of deciduous (oak) forests. Significantly detectable human-made landscape transformation started only after 2000 BC. Our analyses suggest that Neolithic people spread into a landscape that was already open. Humans probably contributed to the spread of oak, and influenced the dynamics of hazel and hornbeam.

  18. Microgravity silicon zoning investigation

    NASA Technical Reports Server (NTRS)

    Kern, E. L.; Gill, G. L., Jr.

    1985-01-01

    The flow instabilities in floating zones of silicon were investigated and methods for investigation of these instabilities in microgravity were defined. Three principal tasks were involved: (1) characterization of the float zone in small diameter rods; (2) investigation of melt flow instabilities in circular melts in silicon disks; and (3) the development of a prototype of an apparatus that could be used in near term space experiments to investigate flow instabilities in a molten zone. It is shown that in a resistance heated zoner with 4 to 7 mm diameter silicon rods that the critical Marangoni number is about 1480 compared to a predicted value of 14 indicative that viable space experiments might be performed. The prototype float zone apparatus is built and specifications are prepared for a flight zoner should a decision be reached to proceed with a space flight experimental investigation.

  19. Effect of climate, intra and inter-annual variability, on nutrients emission (C,N, P) in stream water: lessons from an agricultural long term observatory of the temperate zone

    NASA Astrophysics Data System (ADS)

    Gascuel-Odoux, Chantal; Remi, Dupas; Patrick, Durand; Ophélie, Fovet; Gerard, Gruau; Anne, Jaffrezic; Guillaume, Humbert; Philippe, Merot; Gu, Sen

    2016-04-01

    Agriculture greatly contributes to modify C, N and P cycles, particularly in animal breeding regions due to high inputs. Climatic conditions, intra and inter-annual variabilities, modify nutrient stream water emissions, acting in time on transfer and transformation, accumulation and mobilization processes, connecting and disconnecting in time different compartments (soil, riparian areas, groundwater). In agricultural catchments, nutrient perturbations are dominated by agricultural land use, and decoupling human activities and climate effects is far from easy. Climate change generally appears as a secondary driver compared to land use. If studied, generally only one nutrient is considered. Only long term, high frequency and multiple element data series can decouple these two drivers. The Kervidy-Naizin watershed belongs to the AgrHyS environmental research observatory (http://www6.inra.fr/ore_agrhys_eng), itself included in RBV (French catchment network of the CZO). On this catchment, 6 years of daily data on DOC, NO3, SRP, TP concentrations allow us to analyze the effect of seasonal and inter-annual climatic variabilities on water quality (C, N, P). Different papers have been published on the effect of climate on nitrate (Molenat et al, 2008), SRP and TP (Dupas et al, 2015) and DOC (Humbert et al, 2015). We will present first results comparing the effect of climate on these three major solute forms of C, N and P. While C and P dynamics are very close and controlled by fluctuation of water table downslope, i.e. in riparian areas, mobilizing C and P in time, nitrate dynamics is controlled by GW dynamics upslope acting as the major N reservoir. As example, the dryness conditions in summer appears a key factor of the C and P emissions in autumn. All the three solute forms interact when anoxic conditions are observed in riparian zones. These basic processes explain how climatic variability can influence and explain interactions between C, N and P emissions in stream

  20. Climate regulation, energy provisioning and water purification: Quantifying ecosystem service delivery of bioenergy willow grown on riparian buffer zones using life cycle assessment.

    PubMed

    Styles, David; Börjesson, Pål; D'Hertefeldt, Tina; Birkhofer, Klaus; Dauber, Jens; Adams, Paul; Patil, Sopan; Pagella, Tim; Pettersson, Lars B; Peck, Philip; Vaneeckhaute, Céline; Rosenqvist, Håkan

    2016-12-01

    Whilst life cycle assessment (LCA) boundaries are expanded to account for negative indirect consequences of bioenergy such as indirect land use change (ILUC), ecosystem services such as water purification sometimes delivered by perennial bioenergy crops are typically neglected in LCA studies. Consequential LCA was applied to evaluate the significance of nutrient interception and retention on the environmental balance of unfertilised energy willow planted on 50-m riparian buffer strips and drainage filtration zones in the Skåne region of Sweden. Excluding possible ILUC effects and considering oil heat substitution, strategically planted filter willow can achieve net global warming potential (GWP) and eutrophication potential (EP) savings of up to 11.9 Mg CO2e and 47 kg PO4e ha(-1) year(-1), respectively, compared with a GWP saving of 14.8 Mg CO2e ha(-1) year(-1) and an EP increase of 7 kg PO4e ha(-1) year(-1) for fertilised willow. Planting willow on appropriate buffer and filter zones throughout Skåne could avoid 626 Mg year(-1) PO4e nutrient loading to waters.

  1. Association between high temperature and mortality in metropolitan areas of four cities in various climatic zones in China: a time-series study

    PubMed Central

    2014-01-01

    Background Numerous studies have reported on the associations between ambient temperatures and mortality. However, few multi-city studies have been conducted in developing countries including China. This study aimed to examine the association between high temperature and mortality outcomes in four cities with different climatic characteristics in China to identify the most vulnerable population, detect the threshold temperatures, and provide scientific evidence for public health policy implementations to respond to challenges from extreme heat. Methods A semi-parametric generalized additive model (GAM) with a Poisson distribution was used to analyze the impacts of the daily maximum temperature over the threshold on mortality after controlling for covariates including time trends, day of the week (DOW), humidity, daily temperature range, and outdoor air pollution. Results The temperature thresholds for all-cause mortality were 29°C, 35°C, 33°C and 34°C for Harbin, Nanjing, Shenzhen and Chongqing, respectively. After adjusting for potential confounders including air pollution, strong associations between daily maximum temperature and daily mortality from all-cause, cardiovascular, endocrine and metabolic outcomes, and particularly diabetes, were observed in different geographical cities, with increases of 3.2-5.5%, 4.6-7.5% and 12.5-31.9% (with 14.7-29.2% in diabetes), respectively, with each 1°C increment in the daily maximum temperature over the threshold. A stronger temperature-associated mortality was detected in females compared to males. Additionally, both the population over 55 years and younger adults aged 30 to 54 years reported significant heat-mortality associations. Conclusions Extreme heat is becoming a huge threat to public health and human welfare due to the strong temperature-mortality associations in China. Climate change with increasing temperatures may make the situation worse. Relevant public health strategies and an early extreme weather

  2. Exomoon climate models with the carbonate-silicate cycle and viscoelastic tidal heating

    NASA Astrophysics Data System (ADS)

    Forgan, Duncan; Dobos, Vera

    2016-04-01

    The habitable zone for exomoons with Earth-like properties is a non-trivial manifold, compared to that of Earth-like exoplanets. The presence of tidal heating, eclipses and planetary illumination in the exomoon energy budget combine to produce both circumstellar and circumplanetary habitable regions. Analytical calculations suggest that the circumplanetary habitable region is defined only by an inner edge (with its outer limits determined by orbital stability). Subsequent calculations using 1D latitudinal climate models indicated that the combined effect of eclipses and ice-albedo feedback can produce an outer edge to the circumplanetary habitable zone. But is this outer edge real, or an artefact of the climate model's relative simplicity? We present an upgraded 1D climate model of Earth-like exomoon climates, containing the carbonate-silicate cycle and viscoelastic tidal heating. We conduct parameter surveys of both the circumstellar and circumplanetary habitable zones, and we find that the outer circumplanetary habitable edge remains provided the moon's orbit is not inclined relative to that of the planet. Adding the carbonate-silicate cycle pushes the circumplanetary habitable zone outwards, by allowing increases in atmospheric partial pressure of carbon dioxide to boost the greenhouse effect. Viscoelastic tidal heating widens the habitable zone compared to standard, fixed-Q models. Weakening the tidal heating effect due to melting allows moons to be habitable at higher eccentricity, and pushes the inner circumstellar and circumplanetary habitable zone boundary inwards.

  3. Using multivariate geostatistical methods and geographical clustering to delineate homogeneous winegrowing zones

    NASA Astrophysics Data System (ADS)

    Moral, Francisco J.; Rebollo, Francisco J.; Paniagua, Luis L.; García, Abelardo

    2014-05-01

    Characterization of homogeneous zones is difficult because of the complex combination of factors which could affect it. In winegrowing regions, zoning studies not only define areas according to their potential to produce specific wines but also identify the key drivers behind their variability and optimize vineyard management for sustainable viticulture. With the aim of characterizing the spatial variability of the main vine-related environmental variables and using this information to determine different zones, climate and topographical data were obtained in Extremadura (southwestern Spain), an important wine region. Thus, accurate maps of all climate indices were produced by using regression-kriging as the most suitable algorithm in which exhaustive secondary information on elevation was incorporated. Maps of topography-derived variables were obtained using GIS tools. Later, principal component analysis and multivariate geographic classification were carried out to define areas of similar characteristics, resulting in three zones. This territory zonification constitutes a basic tool for rational region management, demarcation of production areas, studying new cultivar suitability and its interaction with environment, and it can be the basis for viticultural zoning at larger scales. Finally, the suitability of the territory belonging to the Ribera del Guadiana Denomination of Origin for viticulture was analyzed

  4. Anomalous zones (domal)

    SciTech Connect

    Kupfer, D.H. )

    1990-09-01

    Each zone contains several anomalous salt properties (anomalous features). Zones cannot be characterized by any single property Zones are highly variable, lenticular, and discontinuous in detail; however, once established, they commonly have a predictable trend. The individual anomalous features can occur alone (locally in pairs) over areas of various sizes and shapes. These alone occurrences are not anomalous zones. Anomalous zones may be of any origin, and origin is not part of the definition. Typical origins include: primary (sedimentary), external sheath zone, separating two spines of salt, or caused by toroidal flow. The major importance of an anomalous zone is that it consists of various anomalous features distributed discontinuously along the zone. Thus, if three or more anomalous properties are observed together, one should look for others. The anomalous zones observed in the Gulf Coast thus far are vertical, linear, and semicontinuous. Most are reasonably straight, but some bend sharply, end abruptly, or coalesce. Textures in salt involve grain size, color (white to dark gray), grain shape, or grain distribution of the salt. Typical anomalous textures are coarse-grain, poikiloblastic, and friability. A change in color is commonplace and seldom anomalous. Structural anomalous features, broadly defined, account for most of the rest of the anomalous features. Not uncommonly they cause mining problems. Among the structural anomalous features: INCLUSIONS: Sediments, hydrocarbons, brine, gases. Common gases are air (as N{sub 2}), CH-compounds, CO{sub 2}, and H{sub 2}S. STRUCTURES: Sheared salt, undue stabbing or jointing, voids (crystal-lined pockets), permeability, increased porosity COMPOSITION: High anhydrite content, visible anhydrite as grains or boudins, very black salt = disseminated impurities such as clay.

  5. The Immatsiak network of groundwater wells in a small catchment basin in the discontinuous permafrost zone of Northern Quebec, Canada: A unique opportunity for monitoring the impacts of climate change on groundwater (Invited)

    NASA Astrophysics Data System (ADS)

    Fortier, R.; Lemieux, J.; Molson, J. W.; Therrien, R.; Ouellet, M.; Bart, J.

    2013-12-01

    During a summer drilling campaign in 2012, a network of nine groundwater monitoring wells was installed in a small catchment basin in a zone of discontinuous permafrost near the Inuit community of Umiujaq in Northern Quebec, Canada. This network, named Immatsiak, is part of a provincial network of groundwater monitoring wells to monitor the impacts of climate change on groundwater resources. It provides a unique opportunity to study cold region groundwater dynamics in permafrost environments and to assess the impacts of permafrost degradation on groundwater quality and availability as a potential source of drinking water. Using the borehole logs from the drilling campaign and other information from previous investigations, an interpretative cryo-hydrogeological cross-section of the catchment basin was produced which identified the Quaternary deposit thickness and extent, the depth to bedrock, the location of permafrost, one superficial aquifer located in a sand deposit, and another deep aquifer in fluvio-glacial sediments and till. In the summer of 2013, data were recovered from water level and barometric loggers which were installed in the wells in August 2012. Although the wells were drilled in unfrozen zones, the groundwater temperature is very low, near 0.4 °C, with an annual variability of a few tenths of a degree Celsius at a depth of 35 m. The hydraulic head in the wells varied as much as 6 m over the last year. Pumping tests performed in the wells showed a very high hydraulic conductivity of the deep aquifer. Groundwater in the wells and surface water in small thermokarst lakes and at the catchment outlet were sampled for geochemical analysis (inorganic parameters, stable isotopes of oxygen (δ18O) and hydrogen (δ2H), and radioactive isotopes of carbon (δ14C), hydrogen (tritium δ3H) and helium (δ3He)) to assess groundwater quality and origin. Preliminary results show that the signature of melt water from permafrost thawing is observed in the

  6. Managing Climate Change Refugia for Climate Adaptation

    PubMed Central

    Daly, Christopher; Dobrowski, Solomon Z.; Dulen, Deanna M.; Ebersole, Joseph L.; Jackson, Stephen T.; Lundquist, Jessica D.; Millar, Constance I.; Maher, Sean P.; Monahan, William B.; Nydick, Koren R.; Redmond, Kelly T.; Sawyer, Sarah C.; Stock, Sarah; Beissinger, Steven R.

    2016-01-01

    Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change. PMID:27509088

  7. Managing Climate Change Refugia for Climate Adaptation.

    PubMed

    Morelli, Toni Lyn; Daly, Christopher; Dobrowski, Solomon Z; Dulen, Deanna M; Ebersole, Joseph L; Jackson, Stephen T; Lundquist, Jessica D; Millar, Constance I; Maher, Sean P; Monahan, William B; Nydick, Koren R; Redmond, Kelly T; Sawyer, Sarah C; Stock, Sarah; Beissinger, Steven R

    2016-01-01

    Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

  8. Managing climate change refugia for climate adaptation

    USGS Publications Warehouse

    Morelli, Toni L.; Jackson, Stephen T.

    2016-01-01

    Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

  9. The California Biomass Crop Adoption Model estimates biofuel feedstock crop production across diverse agro-ecological zones within the state, under different future climates

    NASA Astrophysics Data System (ADS)

    Kaffka, S.; Jenner, M.; Bucaram, S.; George, N.

    2012-12-01

    Both regulators and businesses need realistic estimates for the potential production of biomass feedstocks for biofuels and bioproducts. This includes the need to understand how climate change will affect mid-tem and longer-term crop performance and relative advantage. The California Biomass Crop Adoption Model is a partial mathematical programming optimization model that estimates the profit level needed for new crop adoption, and the crop(s) displaced when a biomass feedstock crop is added to the state's diverse set of cropping systems, in diverse regions of the state. Both yield and crop price, as elements of profit, can be varied. Crop adoption is tested against current farmer preferences derived from analysis of 10 years crop production data for all crops produced in California, collected by the California Department of Pesticide Regulation. Analysis of this extensive data set resulted in 45 distinctive, representative farming systems distributed across the state's diverse agro-ecological regions. Estimated yields and water use are derived from field trials combined with crop simulation, reported elsewhere. Crop simulation is carried out under different weather and climate assumptions. Besides crop adoption and displacement, crop resource use is also accounted, derived from partial budgets used for each crop's cost of production. Systematically increasing biofuel crop price identified areas of the state where different types of crops were most likely to be adopted. Oilseed crops like canola that can be used for biodiesel production had the greatest potential to be grown in the Sacramento Valley and other northern regions, while sugar beets (for ethanol) had the greatest potential in the northern San Joaquin Valley region, and sweet sorghum in the southern San Joaquin Valley. Up to approximately 10% of existing annual cropland in California was available for new crop adoption. New crops are adopted if the entire cropping system becomes more profitable. In

  10. Environmental Sampling in the Panama Canal Zone. 1 December 1976.

    DTIC Science & Technology

    1977-01-20

    disappearance of even persistent pesticides may be exceptionally rapid in the tropical climate of the Canal Zone. This report also discusses the nature and scope of pest management operations in the Canal Zone.

  11. 76 FR 44880 - Security Zone; Escorted Vessels in Captain of the Port Ohio Valley Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... of the Port (COTP), Sector Ohio Valley Zone. As used in this section, HCPVs are defined as any commercial vessel carrying 500 or more passengers and CDC is defined in 33 CFR 160.204. The proposed security... defined in 33 CFR 3.40-65. This rule would establish security zones that control the movement of persons...

  12. Dentin Caries Zones

    PubMed Central

    Pugach, M.K.; Strother, J.; Darling, C.L.; Fried, D.; Gansky, S.A.; Marshall, S.J.; Marshall, G.W.

    2009-01-01

    Caries Detector staining reveals 4 zones in dentin containing caries lesions, but characteristics of each zone are not well-defined. We therefore investigated the physical and microstructural properties of carious dentin in the 4 different zones to determine important differences revealed by Caries Detector staining. Six arrested dentin caries lesions and 2 normal controls were Caries-Detector-stained, each zone (pink, light pink, transparent, apparently normal) being analyzed by atomic force microscopy (AFM) imaging for microstructure, by AFM nano-indentation for mechanical properties, and by transverse digital microradiography (TMR) for mineral content. Microstructure changes, and nanomechanical properties and mineral content significantly decreased across zones. Hydrated elastic modulus and mineral content from normal dentin to pink Caries-Detector-stained dentin ranged from 19.5 [10.6-25.3] GPa to 1.6 [0.0-5.0] GPa and from 42.9 [39.8-44.6] vol% to 12.4 [9.1-14.2] vol%, respectively. Even the most demineralized pink zone contained considerable residual mineral. PMID:19131321

  13. Disentangling the impacts of climate and human colonization on the flora and fauna of the Australian arid zone over the past 100 ka using stable isotopes in avian eggshell

    NASA Astrophysics Data System (ADS)

    Miller, Gifford H.; Fogel, Marilyn L.; Magee, John W.; Gagan, Michael K.

    2016-11-01

    Throughout the Quaternary, the flora and fauna of Australia evolved and adapted to the high-amplitude, low- and high-frequency climate changes that characterized the ice-age cycles. However, during the last glacial cycle, between ∼120 and 15 ka, unprecedented irreversible changes in flora and fauna occurred, and in that same interval modern humans established their first firm presence in the landscape. Disentangling the impacts of the first-order trend toward a colder, drier planet through the Late Quaternary from the impacts of human colonization has been challenging, from both the chronological and paleoenvironmental perspectives. We utilize the stable isotopes of carbon and oxygen preserved in near-continuous time series of Dromaius (emu) eggshell from five regions across Australia to provide independent reconstructions of ecosystem status and climate over the past 100 ka. Carbon isotopes are determined by the diet consumed by the female bird, whereas oxygen isotopes record the status of local moisture balance in the months prior to breeding. Together, δ13C and δ18O provide ecosystem status and climate from the same dated sample, reducing correlation uncertainties between proxies. Combined with recent improvements in the chronologies of Late Quaternary shorelines fringing inland lake basins and deflation during arid times, these data collectively reaffirm that Australia generally became increasingly, albeit irregularly, drier from the last interglaciation through to the last glacial maximum. Dromaius eggshell δ18O documents peak aridity between 30 and 15 ka, but shows no evidence of exceptional climate change between 60 and 40 ka. In contrast, Dromaius δ13Cdiet documents an irreversible loss of the majority of palatable summer-rainfall-related C4 grasses across the Australian arid zone between 50 and 45 ka, about the same time that the giant megafaunal bird, Genyornis, became extinct, and coincident with human dispersal across the continent. Our data

  14. Correlations between streamflow and intraplate seismicity in the central Virginia, U.S.A., seismic zone: evidence for possible climatic controls

    NASA Astrophysics Data System (ADS)

    Costain, John K.; Bollinger, G. A.

    1991-02-01

    There is no widely accepted explanation for the origin of intraplate earthquakes. The central Virginia seismic zone, like other seismically active intraplate areas, is a spatially isolated area of persistent, diffuse earthquake activity. We suggested earlier that rainfall plays a key role in the generation of intraplate seismicity ("hydroseismicity"). Observed long-period (10-30 years) changes in streamflow (rainfall) are hypothesized to generate intraplate seismicity by diffusion of pore pressure transients from recharge areas of groundwater basins to depth as deep as the brittle-ductile transition. Streamflow and earthquake strain for a 62-year sample from 1925 to 1987 in the central Virginia seismic zone were cumulated, and a least-squares straight-line fit was subtracted to obtain residuals of streamflow and strain. Residual streamflow was differentiated to obtain the rate of change of residual streamflow. We observed common cyclicities with periods of 10-30 years for residual streamflow and strain. From the one-dimensional diffusion equation, we determined the time response of fluid pressure at depths, ψ, in a hydraulically diffusive crust to an impulsive change in fluid pressure at the surface of a groundwater basin. These responses were convolved with the surface streamflow residuals, or, because of results from reservoir-induced seismicity, with the derivatives of these residuals. Root-mean-square values (rms) of the convolutions were computed for ψ = 5, 10, 15 and 20 km and various values of D. For central Virginia, the number of earthquakes, N, within a crustal slice centered on a depth, ψ, was found to be proportional to the rms value of the convolution, suggesting that the number of intraplate earthquakes generated is directly proportional to the magnitude of the rms changes in fluid pore pressure within the crustal slice. These fluctuations in pore pressure, in concert with stress corrosion and hydrolytic weakening, are hypothesized to trigger

  15. Spatial Prediction of Hydraulic Zones from Soil Properties and Secondary Data Using Factorial Kriging Analysis

    NASA Astrophysics Data System (ADS)

    Bevington, James; Morari, Francesco; Scudiero, Elia; Teatini, Pietro; Vellidis, George

    2015-04-01

    The development of pedotransfer functions (PTF) is an important topic in soil science research because there is a critical need for incorporation of vadose zone phenomena into large scale climate models. Soil measurements are inherently spatially dependent and therefore application of geospatial statistics provides an avenue for estimating soil properties. The aim of this study is to define management zones based on soil hydraulic properties. Samples were collected from 50 locations at 4 depths in a 20.8ha field located in the Po River delta in Italy. Water retention curves (WRC) and unsaturated hydraulic conductivity curves (UHC) and were determined via inversion of measurements taken using the Wind (Dane and Topp, 1994) method. This region is in known to have paleo-channel structures and highly heterogeneous soils. Factorial kriging analysis (FKA) was applied to hydraulic parameters in one data set and soil physical properties in another data set at 4 depths. The mapped principal components (PCs) were used in a fuzzy-c means algorithm to define zones of like properties. To examine the physical significance of these zones, curve parameters and hydraulic curves were investigated. Zones were able to distinguish between θ_s(saturated water content), n (shape parameter) and α (inverse of air entry) while θr (residual water content) and Ks (saturated conductivity) were not statistically different between the groups. For curve comparisons, WRC were found to be significantly different between zones at all tensions while effective saturation curves (Se) differ for the majority of tensions (except at 28cm), but UHC did not differ. The spatial relevance of the zones was examined by overlaying hydraulic zones with zones defined using the FKA and fuzzy-c means approach from soil physical properties such as texture and bulk density. The hydraulic zones overlaid with areal accuracy ranging from 46.66% to 92.41%. As there is much similarity between these sets of zones, there

  16. Recent findings relating to firefighter safety zones

    Treesearch

    Bret Butler; Russ Parsons; William Mell

    2015-01-01

    Designation of safety zones is a primary duty of all wildland firefighters. Unfortunately, information regarding what constitutes an adequate safety zone is inadequately defined. Measurements of energy release from wildland fires have been used to develop an empirically based safety zone guideline. The basis for this work is described here.

  17. Late Quaternary climatic vegetational shifts in an ecological transition zone of northern Madagascar: insights from genetic analyses of two endemic rodent species.

    PubMed

    Rakotoarisoa, J-E; Raheriarisena, M; Goodman, S M

    2013-05-01

    The Loky-Manambato region, located in northern Madagascar, is a biotically rich contact zone between different forest biomes. Local current forest cover is composed of both humid and dry formations, which show elevational stratification. A recent phylogeographical study of a regional dry forest rodent, Eliurus carletoni (subfamily Nesomyinae), found genetic evidence of forest contractions between 18 750 and 7500 years BP, which based on extrapolation of the pollen subfossil record, was thought to be associated with an expansion of local humid forests. Herein, we conduct a genetic test of this hypothesis and focused on populations on two neighbouring massifs of forest-dependent rodent species, one associated with low-elevation dry forests (E. carletoni) and the other with higher elevation humid forests (Eliurus tanala). Using mitochondrial markers and a combination of traditional and coalescent-based phylogeographical, historical demographic and population genetic methods, we found evidence of historical connections between populations of E. tanala. Adjacent populations of E. carletoni and E. tanala exhibit opposite historical demographic patterns, and for both, evidence suggests that historical demographic events occurred within the last 25 000 years BP. These findings strongly support the proposed late Quaternary shifts in the floristic composition of the Loky-Manambato region.

  18. Long series relationships between global interannual CO2 increment and climate: evidence for stability and change in role of the tropical and boreal-temperate zones.

    PubMed

    Adams, Jonathan M; Piovesan, Gianluca

    2005-06-01

    Interannual variability in global CO2 increment (averaged from the Mauna Loa and South Pole Stations) shows certain strong spatial relationships to both tropical and temperate temperatures. There is a fairly strong positive year-round correlation between tropical mean annual temperatures (leading by 4 months) and annual CO2 throughout the time series since 1960, agreeing with the generally held view that the tropics play a major role in determining inter-annual variability in CO2 increment, with a major CO2 pulse following a warm year in the tropics. This 'almost no lag' climatic response is very strong during winter and relatively stable in time. However, the correlation with tropical temperature appears to have weakened in the first years of the 1990s in correspondence of the Pinatubo eruption and the positive phase of the AO/NAO. A secondary concurrent temperature signal is linked to summer variations of north temperate belt. Northern summer temperatures in the region 30-60 degrees N-and especially in the land area corresponding to the central east USA-have become relatively more closely correlated with CO2 increment. This trend has become increasingly stronger in recent years, suggesting an increasing role for growing season processes in the northern midlatitudes in affecting global CO2 increment. Once non-lagged annual tropical temperature variations are accounted for, terrestrial ecosystems, especially the temperate-boreal biomes, also show a coherent large scale lagged response. This involves an inverse response to annual temperature of preceding years centered at around 2 years before. This lagged response is most likely linked to internal biogeochemical cycles, in particular N cycling. During the study period north boreal ecosystems show a strengthening of the lagged correlation with temperature in recent years, while the lagged correlation with areas of tropical ecosystems has weakened. Residuals from a multiple correlations based on these climatic

  19. Landscape dynamics assessment of dry climatic zones on the Baikal-Gobi transect from NDVI time series and field investigations data

    NASA Astrophysics Data System (ADS)

    Sayapina, D. O.; Zharnikova, M. A.; Tsydypov, B. Z.; Sodnomov, B. V.; Garmaev, E. Zh

    2016-11-01

    Starting in the eighties of the 20th century, the scientists of the Baikal Institute of Nature Management (BINM SB RAS) have been conducting field observations of the Transbaikalia geosystems transformation due to the change of climate and nature management. An utmost importance is placed on the study of a negative response of the land geosystems. This is shown through their deterioration, degradation, and desertification in particular. Through the years of research (1985-2015) in dry areas of the north of Central Asia, the scientists of the BINM SB RAS established a network of key sites for contact monitoring of the status and dynamics of the geosystems and the negative natural-anthropogenic processes along the Baikal-Gobi meridional transect (51-44° N, 105-107° E). The monitoring of the status and dynamics of the vegetation cover of some key sites is conducted by processing and analysis of multitemporal and multispectral Landsat and MODIS Terra imagery. An automatic analysis of the time variation of NDVI and a comparison with the progress of the index in the previous seasons are performed. The landscape indication of the key sites is made on the basis of satellite imagery and complete geobotanical descriptions. Landscape profiles and facies maps with natural boundaries are created.

  20. Defining needs, defining systems: a critical analysis.

    PubMed

    Dill, A

    1993-08-01

    This article examines the model of need assessment commonly used in social service programs for older adults. Whereas this model defines need as an individual attribute, remediable through programmatic intervention, an alternative formulation suggests that organizational imperatives shape the definition of client need while obscuring their own role in the production of this information. A case study and historical analysis assess the roots of this process and its consequences for clients, staff, and aging programs.

  1. State of microbial communities in paleosols buried under kurgans of the desert-steppe zone in the Middle Bronze Age (27th-26th centuries BC) in relation to the dynamics of climate humidity

    NASA Astrophysics Data System (ADS)

    Khomutova, T. E.; Demkina, T. S.; Borisov, A. V.; Shishlina, I. I.

    2017-02-01

    The size and structure of microbial pool in light chestnut paleosols and paleosolonetz buried under kurgans of the Middle Bronze Age 4600-4500 years ago (the burial mound heights are 45-173 cm), as well as in recent analogues in the desert-steppe zone (Western Ergeni, Salo-Manych Ridge), have been studied. In paleosol profiles, the living microbial biomass estimated from the content of phospholipids varies from 35 to 258% of the present-day value; the active biomass (responsive to glucose addition) in paleosols is 1‒3 orders of magnitude lower than in recent analogues. The content of soil phospholipids is recalculated to that of microbial carbon, and its share in the total soil organic carbon is determined: it is 4.5-7.0% in recent soils and up to three times higher in the remained organic carbon of paleosols. The stability of microbial communities in the B1 horizon of paleosols is 1.3-2.2 times higher than in the upper horizon; in recent soils, it has a tendency to a decrease. The share of microorganisms feeding on plant residues in the ecological-trophic structure of paleosol microbial communities is higher by 23-35% and their index of oligotrophy is 3-5 times lower than in recent analogues. The size of microbial pool and its structure indicate a significantly higher input of plant residues into soils 4600-4500 years ago than in the recent time, which is related to the increase in atmospheric humidity in the studied zone. However, the occurrence depths of salt accumulations in profiles of the studied soils contradict this supposition. A short-term trend of increase in climate humidity is supposed, as indicated by microbial parameters (the most sensitive soil characteristics) or changes in the annual variation of precipitation (its increase in the warm season) during the construction of the mounds under study.

  2. Assessment of Iranian Agroclimatological Zone Classification by Using TVDI (Temperature Vegetation Dryness Index)

    NASA Astrophysics Data System (ADS)

    Asadi, Ebrahim; Lopez-Baeza, Ernesto; Coll Pajaron, M. Amparo; Kouzehgaran, Saeedeh; Haghighat, Masoud

    2016-07-01

    Agricultural zoning is an important tool for authorities to plan and decide about development of the agricultural sector, environmental sustainability issues and plan and provide irrigation and rural infrastructures. Previous different methods have suggested the definition of agroclimatological zones in big areas in Iran, but most of them are not easy to be validated or there are not clear criteria to evaluate whether the zones are correctly defined or not. The current {it Iranian Meteorological Organisation} classification is composed of six significant agroclimatological zones defined using the fundamental climate elements of temperature and precipitation obtained from 30 years data from 180 synoptic stations interpolated using regression kriging methods. Elevation was derived from SRTM (Shuttle Radar Topography Mission) digital elevation model of 90 m resolution. In this paper we assess the homogeneity of each of these conventionally defined agroclimatological zones using {bf TVDI (Temperature Vegetation Dryness Index)} values obtained from MODIS land surface temperature and NDVI operational products of the last three years between 2013 and 2015.

  3. Influence of Climate and Lithology on Soil Phosphorus

    NASA Astrophysics Data System (ADS)

    Wilson, S. G.; Margenot, A. J.; O'Geen, A. T.; Dahlgren, R. A.

    2016-12-01

    Climate and lithology are master variables of pedogenesis. We hypothesize that differences in parent material composition will influence the outcome of soil P fractionation, in concert with climate and the relative degree of chemical weathering. Here, we investigate a novel climo-lithosequence to elucidate the influence of lithology and climate on P dynamics. Three climosequences (elevational transects) spanning four climatic zones (Blue-Oak, Ponderosa Pine, White fir and Red fir), and three bedrock lithologies (basalt, andesite and granodiorite) were investigated across the Sierra Nevada and southern Cascades. Replicate soil samples were collected by genetic horizon at twelve sites (4 climate zones x 3 lithologies) and characterized by a modified Hedley P fractionation method to quantify P into operationally defined pools. Initial results from the fractionation of andesite and basalt transects (granodiorite forthcoming) show large climatic and lithologic effects on soil P fractions, suggesting that the distribution of soil P and the trajectory of P transformations are significantly influenced by lithology as well as climate. For example, in the climatic zone of least weathering (Red fir), all soil P fractions showed significant lithologic effects. In contrast, with increased weathering, parent material effects on soil P fractions become progressively muted, so that in the zone of most intense weathering (Ponderosa Pine), soil P fractions such as Ca-Pi (1 M HCl-Pi) and labile-Pi (Resin Pi + NaHCO3-Pi), no longer show an influence from lithology. Additionally, significant climatic effects were noted for labile-Pi, Ca-Pi and Fe/Al-Pi (0.1 M NaOH-Pi). A strong positive correlation was observed between poorly crystalline Fe/Al-(hydr)oxides (oxalate extractable Fe and Al) and Fe/Al-Pi (p<0.0001). Conversely, a strong negative correlation was observed between crystalline Fe-oxides (inferred by citrate-dithionite extractable Fe) and Fe/Al-Pi (p<0.0001). Results suggest

  4. Generalized provisional seed zones for native plants.

    PubMed

    Bower, Andrew D; St Clair, J Bradley; Erickson, Vicky

    2014-07-01

    Deploying well-adapted and ecologically appropriate plant materials is a core component of successful restoration projects. We have developed generalized provisional seed zones that can be applied to any plant species in the United States to help guide seed movement. These seed zones are based on the intersection of high-resolution climatic data for winter minimum temperature and aridity (as measured by annual heat : moisture index), each classified into discrete bands. This results in the delineation of 64 provisional seed zones for the continental United States. These zones represent areas of relative climatic similarity, and movement of seed within these zones should help to minimize maladaptation. Superimposing Omernik's level III ecoregions over these seed zones distinguishes areas that are similar climatically yet different ecologically. A quantitative comparison of provisional seed zones with level III ecoregions and provisional seed zones within ecoregions for three species showed that provisional seed zone within ecoregion often explained the greatest proportion of variation in a suite of traits potentially related to plant fitness. These provisional seed zones can be considered a starting point for guidelines for seed transfer, and should be utilized in conjunction with appropriate species-specific information as well as local knowledge of microsite differences.

  5. Changes in the soil properties under differently directed climatic fluctuations of the late holocene in the semidesert zone (by the example of the Palasa-Syrt burial mounds in Dagestan)

    NASA Astrophysics Data System (ADS)

    Khokhlova, O. S.; Khokhlov, A. A.; Kuznetsova, A. M.; Malashev, V. Yu.; Magomedov, R. G.

    2015-01-01

    A chronosequence of soils in the area of the Palasa-Syrt burial mounds in the Republic of Dagestan is examined. It includes one paleosol under a kurgan of the Middle Bronze Age (end of the third-beginning of the second millennium BC), twelve paleosols buried at the end of the Late Sarmatian period-the beginning of the Great Migration period (second half of the fourth-first half of the fifth centuries AD), and two background soils. As shown by our study, desertification processes during the Middle Bronze period resulted in the replacement of the light chestnut soil by the brown semidesert soil. In the second studied chronointerval, the soils developed in the semidesert zone; however, the first half of this chronointerval was relatively humid, whereas the second half (in the fifth century AD) was more arid, which was reflected in the soil properties. The grouping of the Late Sarmatian paleosols with respect to their properties made it possible to arrange their chronosequence and, thus, to judge the time of their burial, which was confirmed by the archaeological data. The sequence of changes in the soil properties upon changes in the climatic conditions is identified. The first features that disappear upon humidization and reappear upon aridization of the climate are the features of salinization and solonetzic processes and the character of the biological activity. The 14C age of carbonates also changes. These relatively quick processes are realized in 10-20 years, whereas the changes in the reserves of humus and carbonates require longer periods (supposedly, about 50-100 years).

  6. Viticultural zoning of Graciosa island of the Azores archipelago - Portugal

    NASA Astrophysics Data System (ADS)

    Madruga, João; Reis, Francisco; Felipe, João; Azevedo, Eduardo; Pinheiro, Jorge

    2016-04-01

    The management and sustainability of the traditional vineyards of the Azores settled on lava field terrains is strongly affected by practical limitations of mechanization and high demand on man labor imposed by the typical micro parcel structure of the vineyards. In a recent macrozoning approach study Madruga et al (2015) showed that besides the traditional vineyards there are significant areas in some of the Azores islands whose soils, climate and physiographic characteristics indicate a potential for the development of new vineyard areas offering conditions for better management and sustainability. The objective of this study was to conduct a detailed viticultural zoning at the level of the small mapscale (smaller than 1:25,000), for the island of Graciosa where, besides the traditional lava field terroir, there are also some localized experiences of grapevine production over normal soils, offering thus some comparative information on this type of production conditions. The zoning approach for the present study was based in a geographic information system (GIS) analysis incorporating factors related to climate and topography which was then combined with the soil mapping units fulfilling the suitable criteria concerning the soil properties taken as the most relevant for viticulture, being the result a map of homogeneous environmental units. The climatic zoning examined the direct quantitative variables (precipitation, temperature, evaporation) in relation to climate index, bioclimatic and viticultural specific values. Topography (elevation, slope, aspect, orientation) was analyzed based on the tridimensional models of the islands in GIS to include the best slopes for the mechanization of the vineyard cultural operations (0-15%). Soils were analyzed based on data and soil map units as defined in the soil surveys of the Azores archipelago. The soil properties taken for the analysis and definition of the potential vineyard areas were drainage, water holding capacity

  7. Vadose zone monitoring for hazardous waste sites

    SciTech Connect

    Everett, L.G.; Wilson, L.G.; Hoylman, E.W.

    1983-10-01

    This book describes the applicability of vadose zone monitoring techniques to hazardous waste site investigations. More than 70 different sampling and nonsampling vadose zone monitoring techniques are described in terms of their advantages and disadvantages. Physical, chemical, geologic, topographic, geohydrologic, and climatic constraints for vadose zone monitoring are quantitatively determined. Vadose zone monitoring techniques are categorized for premonitoring, active, and postclosure site assessments. Waste disposal methods are categorized for piles, landfills, impoundments, and land treatment. Conceptual vadose zone monitoring approaches are developed for specific waste disposal method categories.

  8. Modeling hyporheic zone processes

    USGS Publications Warehouse

    Runkel, Robert L.; McKnight, Diane M.; Rajaram, Harihar

    2003-01-01

    Stream biogeochemistry is influenced by the physical and chemical processes that occur in the surrounding watershed. These processes include the mass loading of solutes from terrestrial and atmospheric sources, the physical transport of solutes within the watershed, and the transformation of solutes due to biogeochemical reactions. Research over the last two decades has identified the hyporheic zone as an important part of the stream system in which these processes occur. The hyporheic zone may be loosely defined as the porous areas of the stream bed and stream bank in which stream water mixes with shallow groundwater. Exchange of water and solutes between the stream proper and the hyporheic zone has many biogeochemical implications, due to differences in the chemical composition of surface and groundwater. For example, surface waters are typically oxidized environments with relatively high dissolved oxygen concentrations. In contrast, reducing conditions are often present in groundwater systems leading to low dissolved oxygen concentrations. Further, microbial oxidation of organic materials in groundwater leads to supersaturated concentrations of dissolved carbon dioxide relative to the atmosphere. Differences in surface and groundwater pH and temperature are also common. The hyporheic zone is therefore a mixing zone in which there are gradients in the concentrations of dissolved gasses, the concentrations of oxidized and reduced species, pH, and temperature. These gradients lead to biogeochemical reactions that ultimately affect stream water quality. Due to the complexity of these natural systems, modeling techniques are frequently employed to quantify process dynamics.

  9. Parametrically defined differential equations

    NASA Astrophysics Data System (ADS)

    Polyanin, A. D.; Zhurov, A. I.

    2017-01-01

    The paper deals with nonlinear ordinary differential equations defined parametrically by two relations. It proposes techniques to reduce such equations, of the first or second order, to standard systems of ordinary differential equations. It obtains the general solution to some classes of nonlinear parametrically defined ODEs dependent on arbitrary functions. It outlines procedures for the numerical solution of the Cauchy problem for parametrically defined differential equations.

  10. Organic matter recycling in a shallow coastal zone (NW Mediterranean): The influence of local and global climatic forcing and organic matter lability on hydrolytic enzyme activity

    NASA Astrophysics Data System (ADS)

    Misic, Cristina; Harriague, Anabella Covazzi

    2008-12-01

    Seawater and sediment were collected on a monthly basis from a shallow (10.5 m depth) coastal site in the Ligurian Sea (NW Mediterranean) from November 1993 to December 1994 to determine the main environmental forces that influenced the biogeochemical processes and to study the relationships between the availability and lability of the organic matter (OM) and hydrolytic enzymatic activity. The current direction throughout the sampling year was influenced by the climatic conditions, which showed significant correlations with north atlantic oscillation (NAO) index values. The current generally flowed northwards in spring. This could cause significantly lower transparency values than in the summer, when an eastward current probably reduced the allochthonous input of material from the main local watercourse and contributed to turning the conditions from mesotrophic to oligotrophic. Spring and summer were separated by transitional periods more than by the canonical autumn and winter seasons. These transitions were characterised by a reduction in salinity values and by resuspension caused by water column mixing and a current flowing towards the southwest. The significant inverse correlations of the chlorophyll- a and protein concentrations, bacterial abundance and proteolysis of the bottom seawater and transparency showed the direct influence of resuspension on the organic matter dynamics. Moreover, OM trophic quality influenced the bacterial parameters and the enzymatic activities. The glycolytic β glucosidase and chitinase activities and their bacterial cell-specific hydrolytic rates were higher when substrates such as hydrolysable proteins were available, while they decreased when refractory compounds were abundant. The low leucine aminopeptidase: β glucosidase ratio values observed in the water column were presumably related to the potential ease with which microbes obtained protein-derived materials and energy, the protein hydrolysable fraction being estimated at

  11. New criterion to select the South Atlantic Convergence Zone

    NASA Astrophysics Data System (ADS)

    Ferraz, S. E.; Ambrizzi, T.; Rocha, R. P.

    2007-05-01

    The South Atlantic Convergence Zone (SACZ) is a climatic aspect of the intraseasonal scale that produces intense precipitation in Southeast Brazil during summer Austral. The SACZ is characterized for a high variability convective region located in eastern Cordilheiras of the Andes with northeast-southeast orientation. In addition extend Southeast Amazon until South Atlantic (Zhou and Lau 1998; Liebmann et al, 1999; Carvalho et al, 2004). The many works that studied SACZ (Carvalho, Jones e Liebmann, 2004; Jones et al, 2004, for example) long wave radiation (ROL), is used which proxy of precipitation. In the first moment, it describes the position of event; however the precipitation is more adequate, principally in the used data series obtain of the climatic models. A study of the characterization of the South Atlantic Convergence Zone (SACZ) is presented. It was determined 48 events of ZCAS between 1995 to 2005 during the November to March period. Based on rainfall data, a new criterion was defined in order to select the SACZ events and their results were compared with the previous events. The results indicated that the new criterion did a good job in representing the SACZ. For this reason, um test with climatic model data series (REGCM3 Model, Giorgi et al., 1993) is presented.

  12. Generalized provisional seed zones for native plants

    Treesearch

    Andrew D. Bower; J. Bradley St.Clair; Vicky. Erickson

    2014-01-01

    Deploying well-adapted and ecologically appropriate plant materials is a core component of successful restoration projects. We have developed generalized provisional seed zones that can be applied to any plant species in the United States to help guide seed movement. These seed zones are based on the intersection of high-resolution climatic data for winter minimum...

  13. SIMULATION OF NET INFILTRATION FOR MODERN AND POTENTIAL FUTURE CLIMATES

    SciTech Connect

    J.A. Heveal

    2000-06-16

    This Analysis/Model Report (AMR) describes enhancements made to the infiltration model documented in Flint et al. (1996) and documents an analysis using the enhanced model to generate spatial and temporal distributions over a model domain encompassing the Yucca Mountain site, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone, the average depth below the ground surface (at a given location) from which water is removed by evapotranspiration. The estimates of net infiltration are used for defining the upper boundary condition for the site-scale 3-dimensional Unsaturated-Zone Ground Water Flow and Transport (UZ flow and transport) Model (CRWMS M&O 2000a). The UZ flow and transport model is one of several process models abstracted by the Total System Performance Assessment model to evaluate expected performance of the potential repository at Yucca Mountain, Nevada, in terms of radionuclide transport (CRWMS M&O 1998). The net-infiltration model is important for assessing potential repository-system performance because output from this model provides the upper boundary condition for the UZ flow and transport model that is used to generate flow fields for evaluating potential radionuclide transport through the unsaturated zone. Estimates of net infiltration are provided as raster-based, 2-dimensional grids of spatially distributed, time-averaged rates for three different climate stages estimated as likely conditions for the next 10,000 years beyond the present. Each climate stage is represented using a lower bound, a mean, and an upper bound climate and corresponding net-infiltration scenario for representing uncertainty in the characterization of daily climate conditions for each climate stage, as well as potential climate variability within each climate stage. The set of nine raster grid maps provide spatially

  14. Ecological patterns of nifH genes in four terrestrial climatic zones explored with targeted metagenomics using FrameBot, a new informatics tool.

    PubMed

    Wang, Qiong; Quensen, John F; Fish, Jordan A; Lee, Tae Kwon; Sun, Yanni; Tiedje, James M; Cole, James R

    2013-09-17

    straightforward to assess the genes directly responsible for the ecological function (ecofunctional genes). However, analyzing these genes involves technical challenges beyond those seen for rRNA. In particular, frameshift errors cause garbled downstream protein translations. Our FrameBot tool described here both corrects frameshift errors in query reads and determines their closest matching protein sequences in a set of reference sequences. We validated this new tool with sequences from defined communities and demonstrated the tool's utility on nifH gene fragments sequenced from soils in well-characterized and major terrestrial ecosystem types.

  15. Past equable climates, mixed assemblages, and the regression fallacy

    SciTech Connect

    Cole, K.L. )

    1994-06-01

    Equable climates are often invoked to account for Pleistocene mixed (disharmonious) assemblages of plants or animals. H