TELECOM 2000: An Exploration of the Long-Term Development of Telecommunications in Australia.

ERIC Educational Resources Information Center

Australian Telecommunications Commission, Melbourne.

This document is intended as a guide to directions in Australia's social, economic, and technical future as related to likely trends in the demand for telecommunication facilities in the early Twenty-First Century. From this exploration of the future of telecommunications, nine policy recommendations were made to guide telecommunication research,…

Physical activity and cardiovascular risk factors in a 40- to 42-year-old rural Norwegian population from 1975-2010: repeated cross-sectional surveys.

PubMed

Solbraa, Ane Kristiansen; Holme, Ingar Morten; Graff-Iversen, Sidsel; Resaland, Geir Kåre; Aadland, Eivind; Anderssen, Sigmund Alfred

2014-06-07

Geographical differences in cardiovascular diseases (CVD) have been observed among Norwegian counties. Better long-term health status and higher physical activity (PA) levels have been documented in the county of Sogn & Fjordane compared with other counties. However, recent trends in CVD risk factors have not been documented. The aim of this study was to investigate the secular trends in leisure time physical activity (LTPA) and other CVD risk factors over a 35-year period in a rural population of 40- to 42-year-olds in western Norway and to compare these trends with national trends. Data from eight cross-sectional studies from 1975-2010 (n = 375,682) were obtained from questionnaires and physical examinations and were analyzed using mixed model regression analyses. Decreasing trends were observed for sedentary behavior (for women), moderate PA, smoking, systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL-c) and total cholesterol (TC), whereas increasing trends were observed for body mass index (BMI), triglycerides (TG), light PA, vigorous PA and sedentary behavior for men. Compared to the national trends, the trends in the 40-42-year-olds from Sogn & Fjordane were more beneficial in terms of TG, HDL-c and BMI but less beneficial in terms of SBP and DBP. Over a 35-year-period, this study indicates that the LTPA level has been relatively stable in the county of Sogn & Fjordane. Upward trends were observed in light and vigorous PA, whereas a downward trend was observed in moderate PA. For sedentary behavior, an upward trend was observed in men, whereas a downward trend was observed in women. For smoking, BP and cholesterol decreasing trends were found, but increasing trends were observed in BMI and TG. Compared with the national data, the trends in Sogn & Fjordane were more beneficial for TG, HDL-c and BMI but less beneficial for BP.

Physical activity and cardiovascular risk factors in a 40- to 42-year-old rural Norwegian population from 1975–2010: repeated cross-sectional surveys

PubMed Central

2014-01-01

Background Geographical differences in cardiovascular diseases (CVD) have been observed among Norwegian counties. Better long-term health status and higher physical activity (PA) levels have been documented in the county of Sogn & Fjordane compared with other counties. However, recent trends in CVD risk factors have not been documented. The aim of this study was to investigate the secular trends in leisure time physical activity (LTPA) and other CVD risk factors over a 35-year period in a rural population of 40- to 42-year-olds in western Norway and to compare these trends with national trends. Methods Data from eight cross-sectional studies from 1975–2010 (n = 375,682) were obtained from questionnaires and physical examinations and were analyzed using mixed model regression analyses. Results Decreasing trends were observed for sedentary behavior (for women), moderate PA, smoking, systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL-c) and total cholesterol (TC), whereas increasing trends were observed for body mass index (BMI), triglycerides (TG), light PA, vigorous PA and sedentary behavior for men. Compared to the national trends, the trends in the 40-42-year-olds from Sogn & Fjordane were more beneficial in terms of TG, HDL-c and BMI but less beneficial in terms of SBP and DBP. Conclusions Over a 35-year-period, this study indicates that the LTPA level has been relatively stable in the county of Sogn & Fjordane. Upward trends were observed in light and vigorous PA, whereas a downward trend was observed in moderate PA. For sedentary behavior, an upward trend was observed in men, whereas a downward trend was observed in women. For smoking, BP and cholesterol decreasing trends were found, but increasing trends were observed in BMI and TG. Compared with the national data, the trends in Sogn & Fjordane were more beneficial for TG, HDL-c and BMI but less beneficial for BP. PMID:24906521

Visualization of CDA laboratory reports and long term trends as a possible EHR application for patients and physicians.

PubMed

Obenaus, Manuel; Burgsteiner, Harald

2014-01-01

To increase the patient's acceptance of electronic health records and understanding for their laboratory findings a web application was developed which presents all parameters and possible deviations of standard values in a clear way and visualizes the time based trend of all recorded parameters graphically. Documents corresponding to the Clinical document architecture (CDA) R2 laboratory reports standard and a rapid prototyping framework called Groovy on Grails were used. This work shows, that it is possible to create a useful, standards based tool for patients and physicians with comparatively few resources - an application that could be in similar form a part of an electronic Health Record (EHR) system like the Austrian electronic Health Record (ELGA).

Forest insects and climate change: long-term trends in herbivore damage.

PubMed

Klapwijk, Maartje J; Csóka, György; Hirka, Anikó; Björkman, Christer

2013-10-01

Long-term data sets, covering several decades, could help to reveal the effects of observed climate change on herbivore damage to plants. However, sufficiently long time series in ecology are scarce. The research presented here analyzes a long-term data set collected by the Hungarian Forest Research Institute over the period 1961-2009. The number of hectares with visible defoliation was estimated and documented for several forest insect pest species. This resulted in a unique time series that provides us with the opportunity to compare insect damage trends with trends in weather patterns. Data were analyzed for six lepidopteran species: Thaumetopoea processionea, Tortrix viridana, Rhyacionia buoliana, Malacosoma neustria, Euproctis chrysorrhoea, and Lymantria dispar. All these species exhibit outbreak dynamics in Hungary. Five of these species prefer deciduous tree species as their host plants, whereas R. buoliana is a specialist on Pinus spp. The data were analyzed using general linear models and generalized least squares regression in relation to mean monthly temperature and precipitation. Temperature increased considerably, especially over the last 25 years (+1.6°C), whereas precipitation exhibited no trend over the period. No change in weather variability over time was observed. There was increased damage caused by two species on deciduous trees. The area of damage attributed to R. buoliana decreased over the study period. There was no evidence of increased variability in damage. We conclude that species exhibiting a trend toward outbreak-level damage over a greater geographical area may be positively affected by changes in weather conditions coinciding with important life stages. Strong associations between the geographical extent of severe damage and monthly temperature and precipitation are difficult to confirm, studying the life-history traits of species could help to increase understanding of responses to climate change.

Long-term trends in midwestern milkweed abundances and their relevance to monarch butterfly declines

USGS Publications Warehouse

Zaya, David N.; Pearse, Ian; Spyreas, Gregory

2017-01-01

Declines in monarch butterfly populations have prompted investigation into the sensitivity of their milkweed host plants to land-use change. Documented declines in milkweed abundance in croplands have spurred efforts to promote milkweeds in other habitats. Nevertheless, our current understanding of milkweed populations is poor. We used a long-term plant survey from Illinois to evaluate whether trends in milkweed abundance have caused monarch decline and to highlight the habitat-management practices that promote milkweeds. Milkweed abundance in natural areas has not declined precipitously, although when croplands are considered, changes in agricultural weed management have led to a 68% loss of milkweed available for monarchs across the region. Midsuccessional plant communities with few invasive species provide optimal milkweed habitat. The augmentation of natural areas and the management of existing grasslands, such as less frequent mowing and woody- and exotic-species control, may replace some of the milkweed that has been lost from croplands.

The influence of internal climate variability on heatwave frequency trends

NASA Astrophysics Data System (ADS)

E Perkins-Kirkpatrick, S.; Fischer, E. M.; Angélil, O.; Gibson, P. B.

2017-04-01

Understanding what drives changes in heatwaves is imperative for all systems impacted by extreme heat. We examine short- (13 yr) and long-term (56 yr) heatwave frequency trends in a 21-member ensemble of a global climate model (Community Earth System Model; CESM), where each member is driven by identical anthropogenic forcings. To estimate changes dominantly due to internal climate variability, trends were calculated in the corresponding pre-industrial control run. We find that short-term trends in heatwave frequency are not robust indicators of long-term change. Additionally, we find that a lack of a long-term trend is possible, although improbable, under historical anthropogenic forcing over many regions. All long-term trends become unprecedented against internal variability when commencing in 2015 or later, and corresponding short-term trends by 2030, while the length of trend required to represent regional long-term changes is dependent on a given realization. Lastly, within ten years of a short-term decline, 95% of regional heatwave frequency trends have reverted to increases. This suggests that observed short-term changes of decreasing heatwave frequency could recover to increasing trends within the next decade. The results of this study are specific to CESM and the ‘business as usual’ scenario, and may differ under other representations of internal variability, or be less striking when a scenario with lower anthropogenic forcing is employed.

Long-term agroecosystem research in the central Mississippi river basin: introduction, establishment, and overview.

PubMed

Sadler, E John; Lerch, Robert N; Kitchen, Newell R; Anderson, Stephen H; Baffaut, Claire; Sudduth, Kenneth A; Prato, Anthony A; Kremer, Robert J; Vories, Earl D; Myers, D Brent; Broz, Robert; Miles, Randall J; Young, Fred J

2015-01-01

Many challenges currently facing agriculture require long-term data on landscape-scale hydrologic responses to weather, such as from the Goodwater Creek Experimental Watershed (GCEW), located in northeastern Missouri, USA. This watershed is prone to surface runoff despite shallow slopes, as a result of a significant smectitic clay layer 30 to 50 cm deep that restricts downward flow of water and gives rise to a periodic perched water table. This paper is the first in a series that documents the database developed from GCEW. The objectives of this paper are to (i) establish the context of long-term data and the federal infrastructure that provides it, (ii) describe the GCEW/ Central Mississippi River Basin (CMRB) establishment and the geophysical and anthropogenic context, (iii) summarize in brief the collected research results published using data from within GCEW, (iv) describe the series of papers this work introduces, and (v) identify knowledge gaps and research needs. The rationale for the collection derives from converging trends in data from long-term research, integration of multiple disciplines, and increasing public awareness of increasingly larger problems. The outcome of those trends includes being selected as the CMRB site in the USDA-ARS Long-Term Agro-Ecosystem Research (LTAR) network. Research needs include quantifying watershed scale fluxes of N, P, K, sediment, and energy, accounting for fluxes involving forest, livestock, and anthropogenic sources, scaling from near-term point-scale results to increasingly long and broad scales, and considering whole-system interactions. This special section informs the scientific community about this database and provides support for its future use in research to solve natural resource problems important to US agricultural, environmental, and science policy. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Inconsistencies of interannual variability and trends in long-term satellite leaf area index products.

PubMed

Jiang, Chongya; Ryu, Youngryel; Fang, Hongliang; Myneni, Ranga; Claverie, Martin; Zhu, Zaichun

2017-10-01

Understanding the long-term performance of global satellite leaf area index (LAI) products is important for global change research. However, few effort has been devoted to evaluating the long-term time-series consistencies of LAI products. This study compared four long-term LAI products (GLASS, GLOBMAP, LAI3g, and TCDR) in terms of trends, interannual variabilities, and uncertainty variations from 1982 through 2011. This study also used four ancillary LAI products (GEOV1, MERIS, MODIS C5, and MODIS C6) from 2003 through 2011 to help clarify the performances of the four long-term LAI products. In general, there were marked discrepancies between the four long-term LAI products. During the pre-MODIS period (1982-1999), both linear trends and interannual variabilities of global mean LAI followed the order GLASS>LAI3g>TCDR>GLOBMAP. The GLASS linear trend and interannual variability were almost 4.5 times those of GLOBMAP. During the overlap period (2003-2011), GLASS and GLOBMAP exhibited a decreasing trend, TCDR no trend, and LAI3g an increasing trend. GEOV1, MERIS, and MODIS C6 also exhibited an increasing trend, but to a much smaller extent than that from LAI3g. During both periods, the R 2 of detrended anomalies between the four long-term LAI products was smaller than 0.4 for most regions. Interannual variabilities of the four long-term LAI products were considerably different over the two periods, and the differences followed the order GLASS>LAI3g>TCDR>GLOBMAP. Uncertainty variations quantified by a collocation error model followed the same order. Our results indicate that the four long-term LAI products were neither intraconsistent over time nor interconsistent with each other. These inconsistencies may be due to NOAA satellite orbit changes and MODIS sensor degradation. Caution should be used in the interpretation of global changes derived from the four long-term LAI products. © 2017 John Wiley & Sons Ltd.

Trends in Streamflow Characteristics at Long-Term Gaging Stations, Hawaii

USGS Publications Warehouse

Oki, Delwyn S.

2004-01-01

The surface-water resources of Hawaii have significant cultural, aesthetic, ecologic, and economic importance. Proper management of the surface-water resources of the State requires an understanding of the long- and short-term variability in streamflow characteristics that may occur. The U.S. Geological Survey maintains a network of stream-gaging stations in Hawaii, including a number of stations with long-term streamflow records that can be used to evaluate long-term trends and short-term variability in flow characteristics. The overall objective of this study is to obtain a better understanding of long-term trends and variations in streamflow on the islands of Hawaii, Maui, Molokai, Oahu, and Kauai, where long-term stream-gaging stations exist. This study includes (1) an analysis of long-term trends in flows (both total flow and estimated base flow) at 16 stream-gaging stations, (2) a description of patterns in trends within the State, and (3) discussion of possible regional factors (including rainfall) that are related to the observed trends and variations. Results of this study indicate the following: 1. From 1913 to 2002 base flows generally decreased in streams for which data are available, and this trend is consistent with the long-term downward trend in annual rainfall over much of the State during that period. 2. Monthly mean base flows generally were above the long-term average from 1913 to the early 1940s and below average after the early 1940s to 2002, and this pattern is consistent with the detected downward trends in base flows from 1913 to 2002. 3. Long-term downward trends in base flows of streams may indicate a reduction in ground-water discharge to streams caused by a long-term decrease in ground-water storage and recharge. 4. From 1973 to 2002, trends in streamflow were spatially variable (up in some streams and down in others) and, with a few exceptions, generally were not statistically significant. 5. Short-term variability in streamflow is related to the seasons and to the EL Ni?o-Southern Oscillation phenomenon that may be partly modulated by the phase of the Pacific Decadal Oscillation. 6. At almost all of the long-term stream-gaging stations considered in this study, average total flow (and to a lesser extent average base flow) during the winter months of January to March tended to be low following El Ni?o periods and high following La Ni?a periods, and this tendency was accentuated during positive phases of the Pacific Decadal Oscillation. 7. The El Ni?o-Southern Oscillation phenomenon occurs at a relatively short time scale (a few to several years) and appears to be more strongly related to processes controlling rainfall and direct runoff than ground-water storage and base flow. Long-term downward trends in base flows of streams may indicate a reduction in ground-water storage and recharge. Because ground water provides about 99 percent of Hawaii's domestic drinking water, a reduction in ground-water storage and recharge has serious implications for drinking-water availability. In addition, reduction in stream base flows may reduce habitat availability for native stream fauna and water availability for irrigation purposes. Further study is needed to determine (1) whether the downward trends in base flows from 1913 to 2002 will continue or whether the observed pattern is part of a long-term cycle in which base flows may eventually return to levels measured during 1913 to the early 1940s, (2) the physical causes for the detected trends and variations in streamflow, and (3) whether regional climate indicators successfully can be used to predict streamflow trends and variations throughout the State. These needs for future study underscore the importance of maintaining a network of long-term-trend stream-gaging stations in Hawaii.

Trends and drivers of marine debris on the Atlantic coast of the United States 1997-2007

USGS Publications Warehouse

Ribic, C.A.; Sheavly, S.B.; Rugg, D.J.; Erdmann, Eric S.

2010-01-01

For the first time, we documented regional differences in amounts and long-term trends of marine debris along the US Atlantic coast. The Southeast Atlantic had low land-based and general-source debris loads as well as no increases despite a 19% increase in coastal population. The Northeast (8% population increase) also had low land-based and general-source debris loads and no increases. The Mid-Atlantic (10% population increase) fared the worst, with heavy land-based and general-source debris loads that increased over time. Ocean-based debris did not change in the Northeast where the fishery is relatively stable; it declined over the Mid-Atlantic and Southeast and was correlated with declining regional fisheries. Drivers, including human population, land use status, fishing activity, and oceanic current systems, had complex relationships with debris loads at local and regional scales. Management challenges remain undeniably large but solid information from long-term programs is one key to addressing this pressing pollution issue. ?? 2010.

Trends and drivers of marine debris on the Atlantic coast of the United States 1997-2007.

PubMed

Ribic, Christine A; Sheavly, Seba B; Rugg, David J; Erdmann, Eric S

2010-08-01

For the first time, we documented regional differences in amounts and long-term trends of marine debris along the US Atlantic coast. The Southeast Atlantic had low land-based and general-source debris loads as well as no increases despite a 19% increase in coastal population. The Northeast (8% population increase) also had low land-based and general-source debris loads and no increases. The Mid-Atlantic (10% population increase) fared the worst, with heavy land-based and general-source debris loads that increased over time. Ocean-based debris did not change in the Northeast where the fishery is relatively stable; it declined over the Mid-Atlantic and Southeast and was correlated with declining regional fisheries. Drivers, including human population, land use status, fishing activity, and oceanic current systems, had complex relationships with debris loads at local and regional scales. Management challenges remain undeniably large but solid information from long-term programs is one key to addressing this pressing pollution issue. Published by Elsevier Ltd.

Increased river alkalinization in the Eastern U.S.

PubMed

Kaushal, Sujay S; Likens, Gene E; Utz, Ryan M; Pace, Michael L; Grese, Melissa; Yepsen, Metthea

2013-09-17

The interaction between human activities and watershed geology is accelerating long-term changes in the carbon cycle of rivers. We evaluated changes in bicarbonate alkalinity, a product of chemical weathering, and tested for long-term trends at 97 sites in the eastern United States draining over 260,000 km(2). We observed statistically significant increasing trends in alkalinity at 62 of the 97 sites, while remaining sites exhibited no significant decreasing trends. Over 50% of study sites also had statistically significant increasing trends in concentrations of calcium (another product of chemical weathering) where data were available. River alkalinization rates were significantly related to watershed carbonate lithology, acid deposition, and topography. These three variables explained ~40% of variation in river alkalinization rates. The strongest predictor of river alkalinization rates was carbonate lithology. The most rapid rates of river alkalinization occurred at sites with highest inputs of acid deposition and highest elevation. The rise of alkalinity in many rivers throughout the Eastern U.S. suggests human-accelerated chemical weathering, in addition to previously documented impacts of mining and land use. Increased river alkalinization has major environmental implications including impacts on water hardness and salinization of drinking water, alterations of air-water exchange of CO2, coastal ocean acidification, and the influence of bicarbonate availability on primary production.

Intensified dust storm activity and Valley fever infection in the southwestern United States

NASA Astrophysics Data System (ADS)

Tong, Daniel Q.; Wang, Julian X. L.; Gill, Thomas E.; Lei, Hang; Wang, Binyu

2017-05-01

Climate models have consistently projected a drying trend in the southwestern United States, aiding speculation of increasing dust storms in this region. Long-term climatology is essential to documenting the dust trend and its response to climate variability. We have reconstructed long-term dust climatology in the western United States, based on a comprehensive dust identification method and continuous aerosol observations from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network. We report here direct evidence of rapid intensification of dust storm activity over American deserts in the past decades (1988-2011), in contrast to reported decreasing trends in Asia and Africa. The frequency of windblown dust storms has increased 240% from 1990s to 2000s. This dust trend is associated with large-scale variations of sea surface temperature in the Pacific Ocean, with the strongest correlation with the Pacific Decadal Oscillation. We further investigate the relationship between dust and Valley fever, a fast-rising infectious disease caused by inhaling soil-dwelling fungus (Coccidioides immitis and C. posadasii) in the southwestern United States. The frequency of dust storms is found to be correlated with Valley fever incidences, with a coefficient (r) comparable to or stronger than that with other factors believed to control the disease in two endemic centers (Maricopa and Pima County, Arizona).

Rocky Flats Environmental Technology Site Ecological Monitoring Program 1995 annual report

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

NONE

1995-05-31

The Ecological Monitoring Program (ECMP) was established at the Rocky Flats Environmental Technology Site (Site) in September 1992. At that time, EcMP staff developed a Program Plan that was peer-reviewed by scientists from western universities before submittal to DOE RFFO in January 1993. The intent of the program is to measure several quantitative variables at different ecological scales in order to characterize the Rocky Flats ecosystem. This information is necessary to document ecological conditions at the Site in impacted and nonimpacted areas to determine if Site practices have had ecological impacts, either positive or negative. This information can be usedmore » by managers interested in future use scenarios and CERCLA activities. Others interested in impact analysis may also find the information useful. In addition, these measurements are entered into a database which will serve as a long-term information repository that will document long-term trends and potential future changes to the Site, both natural and anthropogenic.« less

Increasing Juniperus virginiana L. pollen in the Tulsa atmosphere: long-term trends, variability, and influence of meteorological conditions

NASA Astrophysics Data System (ADS)

Flonard, Michaela; Lo, Esther; Levetin, Estelle

2018-02-01

In the Tulsa area, the Cupressaceae is largely represented by eastern red cedar ( Juniperus virginiana L.). The encroachment of this species into the grasslands of Oklahoma has been well documented, and it is believed this trend will continue. The pollen is known to be allergenic and is a major component of the Tulsa atmosphere in February and March. This study examined airborne Cupressaceae pollen data from 1987 to 2016 to determine long-term trends, pollen seasonal variability, and influence of meteorological variables on airborne pollen concentrations. Pollen was collected through means of a Burkard sampler and analyzed with microscopy. Daily pollen concentrations and yearly pollen metrics showed a high degree of variability. In addition, there were significant increases over time in the seasonal pollen index and in peak concentrations. These increases parallel the increasing population of J. virginiana in the region. Pollen data were split into pre- and post-peak categories for statistical analyses, which revealed significant differences in correlations of the two datasets when analyzed with meteorological conditions. While temperature and dew point, among others were significant in both datasets, other factors, like relative humidity, were significant only in one dataset. Analyses using wind direction showed that southerly and southwestern winds contributed to increased pollen concentrations. This study confirms that J. virginiana pollen has become an increasing risk for individuals sensitive to this pollen and emphasizes the need for long-term aerobiological monitoring in other areas.

Birth Cohort and the Black-White Achievement Gap: The Roles of Access and Health Soon After Birth. WP2008-20

ERIC Educational Resources Information Center

Chay, Kenneth Y.; Guryan, Jonathan; Mazumder, Bhashkar

2009-01-01

One literature documents a significant, black-white gap in average test scores, while another finds a substantial narrowing of the gap during the 1980's, and stagnation in convergence after. We use two data sources--the Long Term Trends NAEP and AFQT scores for the universe of applicants to the U.S. military between 1976 and 1991--to show: (1) the…

Birth Cohort and the Black-White Achievement Gap: The Roles of Access and Health Soon after Birth. NBER Working Paper No. 15078

ERIC Educational Resources Information Center

Chay, Kenneth Y.; Guryan, Jonathan; Bhashkar, Mazumder

2009-01-01

One literature documents a significant, black-white gap in average test scores, while another finds a substantial narrowing of the gap during the 1980's, and stagnation in convergence after. We use two data sources -- the Long Term Trends NAEP and AFQT scores for the universe of applicants to the U.S. military between 1976 and 1991 -- to show: 1)…

Long-term trends in railroad service and capacity for U.S. agriculture

DOT National Transportation Integrated Search

2000-11-01

In this paper, the long-term trends in railroad services and capacity for U.S. agriculture are identified and described, particularly in terms of what these trends portend for agricultural shippers absent any change in the economically deregulated en...

Internal Technical Report, 1981 Annual Report, An Analysis of the Response of the Raft River Geothermal Site Monitor Wells

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

Thurow, T.L.; Large, R.M.; Allman, D.W.

1982-04-01

A groundwater monitoring program has been established on the Raft River Geothermal Site since 1978. The objective of this program is to document possible impacts that may be caused by geothermal production and injection on the shallow aquifers used for culinary and irrigation purposes. This annual progress report summarizes data from 12 monitor wells during 1981. These data are compared with long-term trends and are correlated with seasonal patterns, irrigation water use and geothermal production and testing. These results provide a basis for predicting long-term impacts of sustained geothermal production and testing. To date, there has been no effect onmore » the water quality of the shallow aquifers.« less

Long-term trends in sunshine duration and its association with schizophrenia birth rates and age at first registration--data from Australia and the Netherlands.

PubMed

McGrath, John; Selten, Jean-Paul; Chant, David

2002-04-01

Based on the well-described excess of schizophrenia births in winter and spring, we hypothesised that individuals with schizophrenia (a) would be more likely to be born during periods of decreased perinatal sunshine, and (b) those born during periods of less sunshine would have an earlier age of first registration. We undertook an ecological analysis of long-term trends in perinatal sunshine duration and schizophrenia birth rates based on two mental health registers (Queensland, Australia n=6630; The Netherlands n=24,474). For each of the 480 months between 1931 and 1970, the agreement between slopes of the trends in psychosis and long-term sunshine duration series were assessed. Age at first registration was assessed by quartiles of long-term trends in perinatal sunshine duration. Males and females were assessed separately. Both the Dutch and Australian data showed a statistically significant association between falling long-term trends in sunshine duration around the time of birth and rising schizophrenia birth rates for males only. In both the Dutch and Australian data there were significant associations between earlier age of first registration and reduced long-term trends in sunshine duration around the time of birth for both males and females. A measure of long-term trends in perinatal sunshine duration was associated with two epidemiological features of schizophrenia in two separate data sets. Exposures related to sunshine duration warrant further consideration in schizophrenia research.

Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013

USGS Publications Warehouse

Legg, Kristin; Shanahan, Erin; Daley, Rob; Irvine, Kathryn M.

2014-01-01

In mixed and dominant stands, whitebark pine (Pinus albicaulis) occurs in over two million acres within the six national forests and two national parks that comprise the Greater Yellowstone Ecosystem (GYE). Currently, whitebark pine, an ecologically important species, is impacted by multiple ecological disturbances; white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), wildfire, and climate change all pose significant threats to the persistence of whitebark pine populations. Substantial declines in whitebark pine populations have been documented throughout its range.Under the auspices of the Greater Yellowstone Coordinating Committee (GYCC), several agencies began a collaborative, long-term monitoring program to track and document the status of whitebark pine across the GYE. This alliance resulted in the formation of the Greater Yellowstone Whitebark Pine Monitoring Working Group (GYWPMWG), which consists of representatives from the U.S. Forest Service (USFS), National Park Service (NPS), U.S. Geological Survey (USGS), and Montana State University (MSU). This groundbased monitoring program was initiated in 2004 and follows a peer-reviewed protocol (GYWPMWG 2011). The program is led by the Greater Yellowstone Inventory and Monitoring Network (GRYN) of the National Park Service in coordination with multiple agencies. More information about this monitoring effort is available at: http://science. nature.nps.gov/im/units/gryn/monitor/whitebark_pine.cfm. The purpose of this report is to provide a draft summary of the first step-trend analysis for the interagency, long-term monitoring of whitebark pine health to the Interagency Grizzly Bear Study Team (IGBST) as part of a synthesis of the state of whitebark pine in the GYE. Due to the various stages of the analyses and reporting, this is the most efficient way to provide these results to the IGBST.

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

Bishop, L.; Hill, W.J.

A method is proposed to estimate the effect of long-term variations in total ozone on the error incurred in determining a trend in total ozone due to man-made effects. When this method is applied to data from Arosa, Switzerland over the years 1932--1980, a component of the standard error of the trend estimate equal to 0.6 percent per decade is obtained. If this estimate of long-term trend variability at Arosa is not too different from global long-term trend variability, then the threshold ( +- 2 standard errors) for detecting an ozone trend in the 1970's that is outside of whatmore » could be expected from natural variation alone and hence be man-made would range from 1.35% (Reinsel et al, 1981) to 1.8%. The latter value is obtained by combining the Reinsel et al result with the result here, assuming that the error variations that both studies measure are independent and additive. Estimates for long-term trend variation over other time periods are also derived. Simulations that measure the precision of the estimate of long-term variability are reported.« less

Long-term analysis and appropriate metrics of climate change in Mongolia

NASA Astrophysics Data System (ADS)

Jamiyansharav, Khishigbayar

This study addresses three important issues related to long-term climate change study in Mongolia. Mongolia is one of the biggest land-locked countries in Asia and 75--80 percent of the land is rangeland, which is highly vulnerable to climate change. Climate will affect many sectors critical to the country's economic, social, and ecological welfare. Therefore, it is regionally and globally important to evaluate climate change in Mongolia. Chapter 1 discusses the qualitative and descriptive study on exposure characteristics of the 17 Mongolian meteorological stations, which are part of the Global Climate Observing Network (GCON). The global average temperature anomalies are based in part on the GCON stations' meteorological data. To document the possible exposures surrounding the weather stations, the Mongolian meteorological stations were surveyed during July--August 2005. From the total 17 stations, 47 percent were determined strongly influenced by urban character landscape, 41 percent received some anthropogenic influences, and 12 percent had very little to no anthropogenic influences. Even though the Mongolian meteorological stations' exposure characteristics are better than the European and North American stations' the strict adherence in following WMO guidelines is important and urgently needed. Chapter 2 evaluates the long-term (1961--2005) trends in seasonal and annual surface mean, maximum, minimum temperatures and precipitation. Furthermore, this study compares the long-term mean temperature trends with decadal (1998--2007) trends. This chapter also discusses the extreme climate indices on spatial and temporal scales. According to the results, the long-term linear temperature trends show a clear increasing trend whereas the decadal trends show the decreasing trend mostly in winter and spring. The analysis of extreme indices (1961--2001) indicate that most of the stations frost and icing days are decreased and summer days, tropical nights, monthly maximum value of daily minimum, maximum temperatures and growing season length are increased. Precipitation indices varied substantially and there were no unified temporal and spatial pattern. In addition to that, I am suggesting effective temperature as an appropriate metric to evaluate surface heat change because it counts not only air temperature but also surface humidity. Chapter 3 discusses a case study of grazing intensity on surface energy budgets. To evaluate the land atmospheric interactions over the grassland area depending on the different grazing intensity I conducted the case study over the Shortgrass Steppe Long-Term Ecological Research site on Northern Great Plains of US to imply the findings in semiarid shortgrass steppe of Mongolia. The study site has much of similarities with Mongolian shortgrass steppe and has more frequent, high quality data. This study evaluates the impact of grazing on microclimate and energy budgets in a dry (163 mm) and two near-normal (262 and 260 mm) precipitation years based on continuously measured 20 minute interval data. This study helps to describe surface energy partitioning in semi-arid grasslands that has long history of grazing. The main finding of the study is grazing has a potential impact on the energy partitioning under conditions of higher water availability, but not during dry conditions.

Trends in Asset Structure between Not-for-Profit and Investor Owned Hospitals

PubMed Central

Song, Paula H.; Reiter, Kristin L.

2010-01-01

The delivery of health care is a capital intensive industry and thus hospital investment strategy continues to be an important area of interest for both health policy and research. Much attention has been given to hospitals’ capital investment policies with relatively little attention to investments in financial assets, which serve an important role in NFP hospitals. This study describes and analyzes trends in aggregate asset structure between NFP and IO hospitals during the post-capital based PPS implementation period, providing the first documentation of long-term trends in hospital investment. We find hospitals’ aggregate asset structure differs significantly based on ownership, size, and profitability. For both NFP and IO hospitals, financial securities have remained consistent over time, while fixed asset representation has declined in IO hospitals. PMID:20519429

Total nutrient and sediment loads, trends, yields, and nontidal water-quality indicators for selected nontidal stations, Chesapeake Bay Watershed, 1985–2011

USGS Publications Warehouse

Langland, Michael J.; Blomquist, Joel D.; Moyer, Douglas; Hyer, Kenneth; Chanat, Jeffrey G.

2013-01-01

The U.S. Geological Survey, in cooperation with Chesapeake Bay Program (CBP) partners, routinely reports long-term concentration trends and monthly and annual constituent loads for stream water-quality monitoring stations across the Chesapeake Bay watershed. This report documents flow-adjusted trends in sediment and total nitrogen and phosphorus concentrations for 31 stations in the years 1985–2011 and for 32 stations in the years 2002–2011. Sediment and total nitrogen and phosphorus yields for 65 stations are presented for the years 2006–2011. A combined nontidal water-quality indicator (based on both trends and yields) indicates there are more stations classified as “improving water-quality trend and a low yield” than “degrading water-quality trend and a high yield” for total nitrogen. The same type of 2-way classification for total phosphorus and sediment results in equal numbers of stations in each indicator class.

Long-term trends in metals, PCBs, and pesticides in mussels from San Francisco Bay

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

Stephenson, M.D.; Tjeerdema, R.S.; Taberski, K.

1995-12-31

Many contaminant programs have been established to study the geographical distributions and long-term trends of potential pollutants, but unfortunately, many have been short-lived because of economic cutbacks, providing limited information on long-term trends. The California State Mussel Watch program in conjunction with the San Francisco Estuary Institute (in the last 2 years) have provided continues funding for the past 15 years to mussel watch studies in San Francisco Bay. Long-term trends have been identified that describe declines in many organics and metals during the last 15 years. There are also some metals and organics that show no specific trends. Themore » declines indicate that the banning or restriction of usage of some of these contaminants has resulted in substantial decreases of these substances in the environment.« less

2011 Updates on the Long-term Glacier Monitoring Program in Denali National Park and Preserve

NASA Astrophysics Data System (ADS)

Burrows, R. A.; Adema, G. W.; Herreid, S. J.; Arendt, A. A.; Larsen, C. F.

2011-12-01

The area of Denali National Park and Preserve (DENA) dominated by ice is vast, with glaciers covering 3,780 km^2, approximately one sixth of the park's area. They are integral components of the region's hydrologic, ecologic, and geologic systems - with changes to the glacier systems driving the dependent ecosystems. The National Park Service (NPS) conducts long term monitoring of glaciers in Denali with a variety of methods at a range of spatial and temporal scales. This includes seasonal mass balance and surface movement data collection, annual searches for surging glaciers, and decadal areal extent mapping and volume change estimates of all glaciers in the park. If a glacier surge is detected, the event is documented via photography and surface measurements, when possible. In addition, more intensive ground-based GPS surveys of termini and ice surface elevations are conducted on ten study glaciers every 5-10 years, on a rotating basis. Many of the glaciers are located in designated Wilderness, hence the use of mechanized transport is reduced as much as possible. Monitoring objectives are accomplished by park staff and with cooperative agreements with other agencies and universities. Research to understand the context of the long term data is encouraged and supported as much as possible by the NPS and has recently yielded significant results. The year 2011 marks the 20th anniversary of glacier mass balance monitoring on Kahiltna and Traleika Glaciers, located on the south and north sides of Mt. McKinley respectively. A single "index" site near the ELA of each glacier provides an index of winter, summer, and net balances each year as well as flow velocities and changes in surface elevation. Long-term net balance trends are positive from 1991-2003, and negative since 2003, including the 2009-2010 balance year. The average flow velocity at the Kahiltna index site is 200 +/- 21 m/year with a neutral to slightly negative trend, while on Traleika average velocity is 67 +/- 29 m/year with a positive trend. Monitoring glacier behavior and trends using a variety of techniques provides insight to the complexity of glacier change and increases our ability to distinguish local effects from regional and global trends. Parkwide analysis of glacier extent change since the 1950's shows a consistent trend of retreat, except for glaciers that have surged. Longitudinal surface elevation profiling and comparative photography shows relative stability in larger glaciers, but dramatic long-term mass loss on small, relatively low elevation, valley glaciers characteristic of the eastern portion of DENA. These patterns of ice loss are somewhat unique to the Alaska Range and contrast with big losses of ice mass from large glaciers that border the Gulf of Alaska.

Trends in Streamflow Characteristics in Hawaii, 1913-2002

USGS Publications Warehouse

Oki, Delwyn S.

2004-01-01

The surface-water resources of Hawaii have significant cultural, aesthetic, ecologic, and economic importance. In Hawaii, surface-water resources are developed for both offstream uses (for example, drinking water, agriculture, and industrial uses) and instream uses (for example, maintenance of habitat and ecosystems, recreational activities, aesthetic values, maintenance of water quality, conveyance of irrigation and domestic water supplies, and protection of traditional and customary Hawaiian rights). Possible long-term trends in streamflow characteristics have important implications for water users, water suppliers, resource managers, and citizens in the State. Proper management of Hawaii's streams requires an understanding of long-term trends in streamflow characteristics and their potential implications. Effects of long-term downward trends in low flows in streams include potential loss of habitat for native stream fauna and reduced water availability for offstream and instream water uses. Effects of long-term upward trends in high flows in streams include construction of bridges and water-conveyance structures that are potentially unsafe if they are not designed with proper consideration of trends in high flows.

Long-Term Vegetation Trends Detected In Northern Canada Using Landsat Image Stacks

NASA Astrophysics Data System (ADS)

Fraser, R.; Olthof, I.; Carrière, M.; Deschamps, A.; Pouliot, D.

2011-12-01

Evidence of recent productivity increases in arctic vegetation comes from a variety of sources. At local scales, long-term plot measurements in North America are beginning to record increases in vascular plant cover and biomass. At landscape scales, expansion and densification of shrubs has been observed using repeat oblique photographs. Finally, continental-scale increases in vegetation "greenness" have been documented based on analysis of coarse resolution (≥ 1 km) NOAA-AVHRR satellite imagery. In this study we investigated intermediate, regional-level changes occurring in tundra vegetation since 1984 using the Landsat TM and ETM+ satellite image archive. Four study areas averaging 13,619 km2 were located over widely distributed national parks in northern Canada (Ivvavik, Sirmilik, Torngat Mountains, and Wapusk). Time-series image stacks of 16-41 growing-season Landsat scenes from overlapping WRS-2 frames were acquired spanning periods of 17-25 years. Each pixel's unique temporal database of clear-sky values was then analyzed for trends in four indices (NDVI, Tasseled Cap Brightness, Greenness and Wetness) using robust linear regression. The trends were further related to changes in the fractional cover of functional vegetation types using regression tree models trained with plot data and high resolution (≤ 10 m) satellite imagery. We found all four study areas to have a larger proportion of significant (p<0.05) positive greenness trends (range 6.1-25.5%) by comparison to negative trends (range 0.3-4.1%). For the three study areas where regression tree models could be derived, consistent trends of increasing shrub or vascular fractional cover and decreasing bare cover were predicted. The Landsat-based observations were associated with warming trends in each park over the analysis periods. Many of the major changes observed could be corroborated using published studies or field observations.

Long-term trends and a sustainability transition

PubMed Central

Kates, Robert W.; Parris, Thomas M.

2003-01-01

How do long-term global trends affect a transition to sustainability? We emphasize the “multitrend” nature of 10 classes of trends, which makes them complex, contradictory, and often poorly understood. Each class includes trends that make a sustainability transition more feasible as well as trends that make it more difficult. Taken in their entirety, they serve as a checklist for the consideration of global trends that impact place-based sustainability studies. PMID:12829798

ANALYSIS OF TRENDS IN LIFE EXPECTANCIES AND PER CAPITA GROSS DOMESTIC PRODUCT AS WELL AS PHARMACEUTICAL AND NON-PHARMACEUTICAL HEALTHCARE EXPENDITURES.

PubMed

Hermanowski, Tomasz; Bystrov, Victor; Staszewska-Bystrova, Anna; Szafraniec-Buryło, Sylwia I; Rabczenko, Daniel; Kolasa, Katarzyna; Orlewska, Ewa

2015-01-01

Life expectancy is a common measure of population health. Macro-perspective based on aggregated data makes it possible to approximate the impact of different levels of pharmaceutical expenditure on general population health status and is often used in cross-country comparisons. The aim of the study was to determine whether there are long-run relations between life expectancy, total healthcare expenditures, and pharmaceutical expenditures in OECD countries. Common trends in per capita gross domestic products (GDPs) (excluding healthcare expenditures), per capita healthcare expenditures (excluding pharmaceutical expenditures), per capita pharmaceutical expenditures, and life expectancies of women and men aged 60 and 65 were analyzed across OECD countries. Short-term effect of pharmaceutical expenditure onto life expectancy was also estimated by regressing the deviations of life expectancies from their long-term trends onto the deviations of pharmaceutical and non-pharmaceutical health expenditures, as well as GDP from their trends. The dataset was created on the basis of OECD Health Data for 34 countries and the years 1991-2010. Life expectancy variables were used as proxies for the health outcomes, whereas the pharmaceutical and healthcare expenditures represented drug and healthcare consumption, respectively. In general, both expenditures and life expectancies tended to increase in all of the analyzed countries; however, the growth rates differed across the countries. The analysis of common trends indicated the existence of common long-term trends in life expectancies and per capita GDP as well as pharmaceutical and non-pharmaceutical healthcare expenditures. However, there was no evidence that pharmaceutical expenditures provided additional information about the long-term trends in life expectancies beyond that contained in the GDP series. The analysis based on the deviations of variables from their long-term trends allowed concluding that pharmaceutical expenditures significantly influenced life expectancies in the short run. Non-pharmaceutical healthcare expenditures were found to be significant in one out of four models (for life expectancy of women aged 65), while GDPs were found to be insignificant in all four models. The results of the study indicate that there are common long-term trends in life expectancies and per capita GDP as well as pharmaceutical and non-pharmaceutical healthcare expenditures. The available data did not reveal any cause- effect relationship. Other factors, for which the systematic data were not available, may have determined the increase in life expectancy in OECD countries. Significant positive short-term relations between pharmaceutical expenditures and life expectancies in OECD countries were found. The significant short-term effect of pharmaceutical expenditures onto life expectancy means that an increase of pharmaceutical expenditures above long-term trends would lead to a temporary increase in life expectancy above its corresponding long-term trend. However, this effect would not persist as pharmaceutical expenditures and life expectancy would converge to levels determined by the long-term trends.

Interannual Variations in Global Vegetation Phenology Derived from a Long Term AVHRR and MODIS Data Record

NASA Astrophysics Data System (ADS)

Zhang, X.; Friedl, M. A.; Yu, Y.

2013-12-01

Land surface phenology metrics are widely retrieved from satellite observations at regional and global scales, and have been shown to be valuable for monitoring terrestrial ecosystem dynamics in response to extreme climate events and predicting biological responses to future climate scenarios. While the response of spring vegetation greenup to climate warming at mid-to-high latitudes is well-documented, understanding of diverse phenological responses to climate change over entire growing cycles and at broad geographic scales is incomplete. Many studies assume that the timing of individual phenological indicators in responses to climate forcing is independent of phenological events that occur at other times during the growing season. In this paper we use a different strategy. Specifically, we hypothesize that integrating sequences of key phenological indicators across growing seasons provides a more effective way to capture long-term variation in phenology in response to climate change. To explore this hypothesis we use global land surface phenology metrics derived from the Version 3 Long Term Vegetation Index Products from Multiple Satellite Data Records data set to examine interannual variations and trends in global land surface phenology from 1982-2010. Using daily enhanced vegetation index (EVI) data at a spatial resolution of 0.05 degrees, we model the phenological trajectory for each individual pixel using piecewise logistic models. The modeled trajectories were then used to detect phenological indicators including the onset of greenness increase, the onset of greenness maximum, the onset of greenness decrease, the onset of greenness minimum, and the growing season length, among others at global scale. The quality of land surface phenology detection for individual pixels was calculated based on metrics that characterize the EVI quality and model fits in annual time series at each pixel. Phenological indicators characterized as having good quality were then used to detect interannual variation and long-term trends using linear and nonlinear trend analysis techniques.

Evolutionary Trends and the Salience Bias (with Apologies to Oil Tankers, Karl Marx, and Others).

ERIC Educational Resources Information Center

McShea, Daniel W.

1994-01-01

Examines evolutionary trends, specifically trends in size, complexity, and fitness. Notes that documentation of these trends consists of either long lists of cases, or descriptions of a small number of salient cases. Proposes the use of random samples to avoid this "saliency bias." (SR)

Long-term trends in dissolved iron and DOC concentration linked to nitrate depletion in riparian soils

NASA Astrophysics Data System (ADS)

Musolff, Andreas; Selle, Benny; Fleckenstein, Jan H.; Oosterwoud, Marieke R.; Tittel, Jörg

2016-04-01

The instream concentrations of dissolved organic carbon (DOC) are rising in many catchments of the northern hemisphere. Elevated concentrations of DOC, mainly in the form of colored humic components, increase efforts and costs of drinking water purification. In this study, we evaluated a long-term dataset of 110 catchments draining into German drinking water reservoirs in order to assess sources of DOC and drivers of a potential long-term change. The average DOC concentrations across the wide range of different catchments were found to be well explained by the catchment's topographic wetness index. Higher wetness indices were connected to higher average DOC concentrations, which implies that catchments with shallow topography and pronounced riparian wetlands mobilize more DOC. Overall, 37% of the investigated catchments showed a significant long-term increase in DOC concentrations, while 22% exhibited significant negative trends. Moreover, we found that increasing trends in DOC were positively correlated to trends in dissolved iron concentrations at pH≤6 due to remobilization of DOC previously sorbed to iron minerals. Both, increasing trends in DOC and dissolve iron were found to be connected to decreasing trends and low concentrations of nitrate (below ~6 mg/L). This was especially observed in forested catchments where atmospheric N-depositions were the major source for nitrate availability. In these catchments, we also found long-term increases of phosphate concentrations. Therefore, we argue that dissolved iron, DOC and phosphate were jointly released under iron-reducing conditions when nitrate as a competing electron acceptor was too low in concentrations to prevent the microbial iron reduction. In contrast, we could not explain the observed increasing trends in DOC, iron and phosphate concentrations by the long-term trends of pH, sulfate or precipitation. Altogether this study gives strong evidence that both, source and long-term increases in DOC are primarily controlled by riparian wetland soils within the catchments. Here, the achievement of a long-term reduction in nitrogen deposition may in turn lead to a more pronounced iron reduction and a subsequent release of DOC and other iron-bound substances such as phosphate.

Trends in asset structure between not-for-profit and investor-owned hospitals.

PubMed

Song, Paula H; Reiter, Kristin L

2010-12-01

The delivery of health care is a capital-intensive industry, and thus, hospital investment strategy continues to be an important area of interest for both health policy and research. Much attention has been given to hospitals' capital investment policies with relatively little attention to investments in financial assets, which serve an important role in not-for-profit (NFP) hospitals. This study describes and analyzes trends in aggregate asset structure between NFP and investor-owned (IO) hospitals during the post-capital-based prospective payment system implementation period, providing the first documentation of long-term trends in hospital investment. The authors find hospitals' aggregate asset structure differs significantly based on ownership, size, and profitability. For both NFP and IO hospitals, financial securities have remained consistent over time, while fixed asset representation has declined in IO hospitals.

Long-term variations of the upper atmosphere parameters on Rome ionosonde observations and their interpretation

NASA Astrophysics Data System (ADS)

Perrone, Loredana; Mikhailov, Andrey; Cesaroni, Claudio; Alfonsi, Lucilla; Santis, Angelo De; Pezzopane, Michael; Scotto, Carlo

2017-09-01

A recently proposed self-consistent approach to the analysis of thermospheric and ionospheric long-term trends has been applied to Rome ionosonde summer noontime observations for the (1957-2015) period. This approach includes: (i) a method to extract ionospheric parameter long-term variations; (ii) a method to retrieve from observed foF1 neutral composition (O, O2, N2), exospheric temperature, Tex and the total solar EUV flux with λ < 1050 Å; and (iii) a combined analysis of the ionospheric and thermospheric parameter long-term variations using the theory of ionospheric F-layer formation. Atomic oxygen, [O] and [O]/[N2] ratio control foF1 and foF2 while neutral temperature, Tex controls hmF2 long-term variations. Noontime foF2 and foF1 long-term variations demonstrate a negative linear trend estimated over the (1962-2010) period which is mainly due to atomic oxygen decrease after ˜1990. A linear trend in (δhmF2)11y estimated over the (1962-2010) period is very small and insignificant reflecting the absence of any significant trend in neutral temperature. The retrieved neutral gas density, ρ atomic oxygen, [O] and exospheric temperature, Tex long-term variations are controlled by solar and geomagnetic activity, i.e. they have a natural origin. The residual trends estimated over the period of ˜5 solar cycles (1957-2015) are very small (<0.5% per decade) and statistically insignificant.

Time series smoother for effect detection.

PubMed

You, Cheng; Lin, Dennis K J; Young, S Stanley

2018-01-01

In environmental epidemiology, it is often encountered that multiple time series data with a long-term trend, including seasonality, cannot be fully adjusted by the observed covariates. The long-term trend is difficult to separate from abnormal short-term signals of interest. This paper addresses how to estimate the long-term trend in order to recover short-term signals. Our case study demonstrates that the current spline smoothing methods can result in significant positive and negative cross-correlations from the same dataset, depending on how the smoothing parameters are chosen. To circumvent this dilemma, three classes of time series smoothers are proposed to detrend time series data. These smoothers do not require fine tuning of parameters and can be applied to recover short-term signals. The properties of these smoothers are shown with both a case study using a factorial design and a simulation study using datasets generated from the original dataset. General guidelines are provided on how to discover short-term signals from time series with a long-term trend. The benefit of this research is that a problem is identified and characteristics of possible solutions are determined.

Time series smoother for effect detection

PubMed Central

Lin, Dennis K. J.; Young, S. Stanley

2018-01-01

In environmental epidemiology, it is often encountered that multiple time series data with a long-term trend, including seasonality, cannot be fully adjusted by the observed covariates. The long-term trend is difficult to separate from abnormal short-term signals of interest. This paper addresses how to estimate the long-term trend in order to recover short-term signals. Our case study demonstrates that the current spline smoothing methods can result in significant positive and negative cross-correlations from the same dataset, depending on how the smoothing parameters are chosen. To circumvent this dilemma, three classes of time series smoothers are proposed to detrend time series data. These smoothers do not require fine tuning of parameters and can be applied to recover short-term signals. The properties of these smoothers are shown with both a case study using a factorial design and a simulation study using datasets generated from the original dataset. General guidelines are provided on how to discover short-term signals from time series with a long-term trend. The benefit of this research is that a problem is identified and characteristics of possible solutions are determined. PMID:29684033

The Uncertainty of Long-term Linear Trend in Global SST Due to Internal Variation

NASA Astrophysics Data System (ADS)

Lian, Tao

2016-04-01

In most parts of the global ocean, the magnitude of the long-term linear trend in sea surface temperature (SST) is much smaller than the amplitude of local multi-scale internal variation. One can thus use the record of a specified period to arbitrarily determine the value and the sign of the long-term linear trend in regional SST, and further leading to controversial conclusions on how global SST responds to global warming in the recent history. Analyzing the linear trend coefficient estimated by the ordinary least-square method indicates that the linear trend consists of two parts: One related to the long-term change, and the other related to the multi-scale internal variation. The sign of the long-term change can be correctly reproduced only when the magnitude of the linear trend coefficient is greater than a theoretical threshold which scales the influence from the multi-scale internal variation. Otherwise, the sign of the linear trend coefficient will depend on the phase of the internal variation, or in the other words, the period being used. An improved least-square method is then proposed to reduce the theoretical threshold. When apply the new method to a global SST reconstruction from 1881 to 2013, we find that in a large part of Pacific, the southern Indian Ocean and North Atlantic, the influence from the multi-scale internal variation on the sign of the linear trend coefficient can-not be excluded. Therefore, the resulting warming or/and cooling linear trends in these regions can-not be fully assigned to global warming.

Tracking Trends in Fractional Forest Cover Change using Long Term Data from AVHRR and MODIS

NASA Astrophysics Data System (ADS)

Kim, D. H.; DiMiceli, C.; Sohlberg, R. A.; Hansen, M.; Carroll, M.; Kelly, M.; Townshend, J. R.

2014-12-01

Tree cover affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Accurate and long-term continuous observation of tree cover change is critical for the study of the gradual ecosystem change. Tree cover is most commonly inferred from categorical maps which may inadequately represent within-class heterogeneity for many analyses. Alternatively, Vegetation Continuous Fields data measures fractions or proportions of pixel area. Recent development in remote sensing data processing and cross sensor calibration techniques enabled the continuous, long-term observations such as Land Long-Term Data Records. Such data products and their surface reflectance data have enhanced the possibilities for long term Vegetation Continuous Fields data, thus enabling the estimation of long term trend of fractional forest cover change. In this presentation, we will summarize the progress in algorithm development including automation of training selection for deciduous and evergreen forest, the preliminary results, and its future applications to relate trends in fractional forest cover change and environmental change.

Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966-2015

NASA Astrophysics Data System (ADS)

Mianabadi, Ameneh; Shirazi, Pooya; Ghahraman, Bijan; Coenders-Gerrits, A. M. J.; Alizadeh, Amin; Davary, Kamran

2018-02-01

In arid and semi-arid regions, water scarcity is the crucial issue for crop production. Identifying the spatial and temporal trends in aridity, especially during the crop-growing season, is important for farmers to manage their agricultural practices. This will become especially relevant when considering climate change projections. To reliably determine the actual trends, the influence of short- and long-term memory should be removed from the trend analysis. The objective of this study is to investigate the effect of short- and long-term memory on estimates of trends in two aridity indicators—the inverted De Martonne (ϕ IDM ) and Budyko (ϕ B ) indices. The analysis is done using precipitation and temperature data over Iran for a 50-year period (1966-2015) at three temporal scales: annual, wheat-growing season (October-June), and maize-growing season (May-November). For this purpose, the original and the modified Mann-Kendall tests (i.e., modified by three methods of trend free pre-whitening (TFPT), effective sample size (ESS), and long-term persistence (LTP)) are used to investigate the temporal trends in aridity indices, precipitation, and temperature by taking into account the effect of short- and long-term memory. Precipitation and temperature data were provided by the Islamic Republic of Iran Meteorological Organization (IRIMO). The temporal trend analysis showed that aridity increased from 1966 to 2015 at the annual and wheat-growing season scales, which is due to a decreasing trend in precipitation and an increasing trend in mean temperature at these two timescales. The trend in aridity indices was decreasing in the maize-growing season, since precipitation has an increasing trend for most parts of Iran in that season. The increasing trend in aridity indices is significant in Western Iran, which can be related to the significantly more negative trend in precipitation in the West. This increasing trend in aridity could result in an increasing crop water requirement and a significant reduction in the crop production and water use efficiency. Furthermore, the modified Mann-Kendall tests indicated that unlike temperature series, precipitation, ϕ IDM , and ϕ B series are not affected by short- and long-term memory. Our results can help decision makers and water resource managers to adopt appropriate policy strategies for sustainable development in the field of irrigated agriculture and water resources management.

Long memory in international financial markets trends and short movements during 2008 financial crisis based on variational mode decomposition and detrended fluctuation analysis

NASA Astrophysics Data System (ADS)

Lahmiri, Salim

2015-11-01

The purpose of this study is to investigate long-range dependence in trend and short variation of stock market price and return series before, during, and after 2008 financial crisis. Variational mode decomposition (VMD), a newly introduced technique for signal processing, is adopted to decompose stock market data into a finite set of modes so as to obtain long term trends and short term movements of stock market data. Then, the detrended fluctuation analysis (DFA) and range scale (R/S) analysis are used to estimate Hurst exponent in each variational mode obtained from VMD. For both price and return series, the empirical results from twelve international stock markets show evidence that long term trends are persistent, whilst short term variations are anti-persistent before, during, and after 2008 financial crisis.

The DOD Humanitarian and Civic Assistance Program Concepts, Trends, Medical Challenges

DTIC Science & Technology

1997-03-01

program improvements; measuring program performance and effectiveness; and defining military roles relevant to training, long term benefits, and the...support conclusions relevant to trends, benefits, challenges, suggested improvements, and suggested areas for future research. 15. SUBJECT TERMS 16...a Long Term Medical Benefit ................ 28 CONCLUSION

High-resolution mapping of global surface water and its long-term changes

NASA Astrophysics Data System (ADS)

Pekel, J. F.; Cottam, A.; Gorelick, N.; Belward, A.

2016-12-01

The location and persistence of surface water is both affected by climate and human activity and affects climate, biological diversity and human wellbeing. Global datasets documenting surface water location and seasonality have been produced but measuring long-term changes at high resolution remains a challenge.To address the dynamic nature of water, the European Commission's Joint Research Centre (JRC), working with the Google Earth Engine (GEE) team has processed each single pixel acquired by Landsat 5, 7, and 8 between 16th March 1984 to 10th October 2015 (> 3.000.000 Landsat scenes, representing > 1823 Terabytes of data).The produced dataset record months and years when water was present across 32 year, were occurrence changed and what form changes took in terms of seasonality and persistence, and document intra-annual persistence, inter-annual variability, and trends.This validated dataset shows that impacts of climate change and climate oscillations on surface water occurrence can be measured and that evidence can be gathered showing how surface water is altered by human activities.Freely available, we anticipate that this dataset will provide valuable information to those working in areas linked to security of water supply for agriculture, industry and human consumption, for assessing water-related disaster reduction and recovery and for the study of waterborne pollution and disease spread. The maps will also improve surface boundary condition setting in climate and weather models, improve carbon emissions estimates, inform regional climate change impact studies, delimit wetlands for biodiversity and determine desertification trends. Issues such as dam building (and less widespread dam removal), disappearing rivers, the geopolitics of water distribution and coastal erosion are also addressed.

Climate-tree growth models in relation to long-term growth trends of white oak in Pennsylvania

Treesearch

D. D. Davis; R. P. Long

2003-01-01

We examined long-term growth trends of white oak by comparing tree-ring chronologies developed from an old-growth stand, where the average tree age was 222 years, with a second-growth stand where average tree age was 78 years. Evaluation of basal area growth trends suggested that an anomalous decrease in basal area increment trend occurred in both stands during the...

Verbal and nonverbal indicators of quality of communication between care staff and residents in ethnoculturally and linguistically diverse long-term care settings.

PubMed

Small, Jeff; Chan, Sing Mei; Drance, Elisabeth; Globerman, Judith; Hulko, Wendy; O'Connor, Deborah; Perry, JoAnn; Stern, Louise; Ho, Lorraine

2015-09-01

Linguistic and ethnocultural diversity in long-term residential care is a growing trend in many urban settings. When long-term care staff and residents do not share the same language or ethnocultural background, the quality of their communication and care are jeopardized. There is very little research addressing how staff and residents communicate when they experience a mismatch in their language and ethnocultural backgrounds. Thus, the goals of the present study were to 1) document the verbal and nonverbal behaviours used by staff and residents in diverse interactions, and 2) identify and account for behaviours that either promoted or detracted from positive communication by drawing on principles from 'Communication Accommodation Theory'. Two long-term care facilities in British Columbia Canada were selected due to the diverse linguistic and ethnocultural backgrounds of their staff and residents. Twenty-seven staff and 27 residents consented to being video-recorded during routine activities (e.g., mealtimes, recreational activities). The recorded observations were transcribed, translated, and coded using qualitative descriptive and interpretive analyses. A number of verbal and nonverbal behaviours were identified and interpreted in relation to whether they promoted or detracted from positive communication. The findings point to considering a variety of proactive strategies that staff and administrators could employ to effectively accommodate to language and ethnocultural diversity in long-term care practice.

What CFOs should know before venturing into the cloud.

PubMed

Rajendran, Janakan

2013-05-01

There are three major trends in the use of cloud-based services for healthcare IT: Cloud computing involves the hosting of health IT applications in a service provider cloud. Cloud storage is a data storage service that can involve, for example, long-term storage and archival of information such as clinical data, medical images, and scanned documents. Data center colocation involves rental of secure space in the cloud from a vendor, an approach that allows a hospital to share power capacity and proven security protocols, reducing costs.

On the decline of the Rusty Blackbird and the use of ornithological literature to document long-term population trends

USGS Publications Warehouse

Greenberg, R.; Droege, S.

1999-01-01

Unlike most North American blackbirds, Rusty Blackbirds (Euphagus carolensis) have shown steep population declines. Declines of approximately 90% are indicated for three recent decades from the Breeding Bird Survey, Christmas Bird Counts, and Quebec Checklist Program. Analyses of abundance classifications in bird distribution books and annotated checklists reveal an overlooked but long-term decline dating back to at least the early part of this century. Rusty Blackbirds were described as very common to abundant in 5656 of the pre-192O published accounts, 19% of the 1921-1950 accounts, and only 7% of the post-1950 accounts. Rusty Blackbirds were described as uncommon in none of the pre-1950 accounts, 18% of the 1951-1980 accounts, and 43% of the post-1980 accounts. A similar pattern was found for analyses based on local checklists. Destruction of wooded wetlands on wintering grounds, acid precipitation, and the conversion of boreal forest wetlands could have contributed to these declines. Systematic analysis of regional guides and checklists provides a valuable tool for examining large-scale and long-term population changes in birds.

Long-Term Trends, Variability and Extremes of In Situ Sea Surface Temperature Measured Along the Eastern Adriatic Coast and its Relationship to Hemispheric Processes

NASA Astrophysics Data System (ADS)

Grbec, Branka; Matić, Frano; Beg Paklar, Gordana; Morović, Mira; Popović, Ružica; Vilibić, Ivica

2018-02-01

This paper examines long-term series of in situ sea surface temperature (SST) data measured at nine coastal and one open sea stations along the eastern Adriatic Sea for the period 1959-2015. Monthly and yearly averages were used to document SST trends and variability, while clustering and connections to hemispheric indices were achieved by applying the Principal Component Analysis (PCA) and Self-Organizing Maps (SOM) method. Both PCA and SOM revealed the dominance of temporal changes with respect to the effects of spatial differences in SST anomalies, indicating the prevalence of hemispheric processes over local dynamics, such as bora wind spatial inhomogeneity. SST extremes were connected with blocking atmospheric patterns. A substantial warming between 1979 and 2015, in total exceeding 1 °C, was preceded by a period with a negative SST trend, implying strong multidecadal variability in the Adriatic. The strongest connection was found between yearly SST and the East Atlantic (EA) pattern, while North Atlantic Oscillation (NAO) and East Atlantic/West Russia (EAWR) patterns were found to also affect February SST values. Quantification of the Adriatic SST and their connection to hemispheric indices allow for more precise projections of future SST, considered to be rather important for Adriatic thermohaline circulation, biogeochemistry and fisheries, and sensitive to ongoing climate change.

Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA

Treesearch

Rakesh Minocha; Swathi A. Turlapati; Stephanie Long; William H. McDowell; Subhash C. Minocha

2015-01-01

We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements...

An exotic long-term pattern in stock price dynamics.

PubMed

Wei, Jianrong; Huang, Jiping

2012-01-01

To accurately predict the movement of stock prices is always of both academic importance and practical value. So far, a lot of research has been reported to help understand the behavior of stock prices. However, some of the existing theories tend to render us the belief that the time series of stock prices are unpredictable on a long-term timescale. The question arises whether the long-term predictability exists in stock price dynamics. In this work, we analyze the price reversals in the US stock market and the Chinese stock market on the basis of a renormalization method. The price reversals are divided into two types: retracements (the downward trends after upward trends) and rebounds (the upward trends after downward trends), of which the intensities are described by dimensionless quantities, R(t) and R(b), respectively. We reveal that for both mature and emerging markets, the distribution of either retracements R(t) or rebounds R(b) shows two characteristic values, 0.335 and 0.665, both of which are robust over the long term. The methodology presented here provides a way to quantify the stock price reversals. Our findings strongly support the existence of the long-term predictability in stock price dynamics, and may offer a hint on how to predict the long-term movement of stock prices.

Relation between annual trends in food pantry use and long-term unemployment in New York State, 2002-2012.

PubMed

Shackman, Gene; Yu, Chengxuan; Edmunds, Lynn S; Clarke, Lewis; Sekhobo, Jackson P

2015-03-01

We examined the correlation between trends in meals provided through food pantries and long-term unemployment from 2002 through 2012. The New York State Hunger Prevention and Nutrition Assistance Program provided about 192 million meals through food pantries in 2012-double the number before the Great Recession. Annual food pantry use was strongly correlated with long-term unemployment and remained on an upward trend from 2006 through 2012, even after the Great Recession had ended. These findings suggest that efforts to reduce hunger and food insecurity should continue to be priorities.

Overview of the Long-term Ozone Trends and Uncertainties in the Stratosphere(LOTUS) SPARC Activity

NASA Astrophysics Data System (ADS)

Petropavlovskikh, I. V.; Hubert, D.; Godin-Beekman, S.; Damadeo, R. P.; Sofieva, V.; Hassler, B.

2017-12-01

WMO/UNEP Assessments on the state of the ozone layer (aka Ozone Assessments) require an accurate evaluation of both total ozone and ozone profile long-term trends. These trend results are of utmost importance in order to evaluate the success of the Montreal Protocol with regards to the recovery of the ozone layer and the effect of climate change on this recovery, in the main regions of the stratosphere (polar, mid-latitudes, tropics). A previous activity sponsored by SPARC, IO3C, IGACO-O3 and NDACC (SI2N) successfully provided estimates of ozone profile decreasing trend in the period 1979 - 1997 and recovery trend in the period 1998 -2012, from a variety of long term records, however its results were different from those published in the WMO 2014 Ozone Assessment report. For the WMO/UNEP 2018 Ozone Assessment, a clear understanding of ozone trends and their significance as a function of altitude and latitude is still needed, nearly 20 years after the peak of ozone depleting substances in the stratosphere. In the most recent years, new merged satellite data sets and long awaited homogenized ozonesonde data series have been produced. There is thus a strong interest in the scientific community to understand limitations in determining significance of ozone recovery. In order to address the issues left pending after the end of SI2N, a comprehensive evaluation of all long term data sets available together with their relative drifts was performed through the SPARC LOTUS (Long-term Ozone Trends and uncertainties in Stratosphere) activity. Evaluation of consistencies in results from various statistical trend regression models, sensitivity to the selection of predictors, evaluation of sampling-related uncertainties and impact of the measurement error propagation on ozone trend calculation was among subjects of investigation. This presentation will provide overview of the LOTUS project goals, provide highlights of the results and discuss the future goals.

A retrospective investigation of energy efficiency standards: Policies may have accelerated long term declines in appliance costs

DOE PAGES

Van Buskirk, R. D.; Kantner, C. L. S.; Gerke, B. F.; ...

2014-11-14

We perform a retrospective investigation of multi-decade trends in price and life-cycle cost (LCC) for home appliances in periods with and without energy efficiency (EE) standards and labeling polices. In contrast to the classical picture of the impact of efficiency standards, the introduction and updating of appliance standards is not associated with a long-term increase in purchase price; rather, quality-adjusted prices undergo a continued or accelerated long-term decline. In addition, long term trends in appliance LCCs—which include operating costs—consistently show an accelerated long term decline with EE policies. We also show that the incremental price of efficiency improvements has declinedmore » faster than the baseline product price for selected products. These observations are inconsistent with a view of EE standards that supposes a perfectly competitive market with static supply costs. These results suggest that EE policies may be associated with other forces at play, such as innovation and learning-by-doing in appliance production and design, that can affect long term trends in quality-adjusted prices and LCCs.« less

Emerging trends in the finance and delivery of long-term care: public and private opportunities and challenges.

PubMed

Cohen, M A

1998-02-01

A number of key trends are emerging in long-term care related to financing, new models of service delivery, and shifts in consumer expectations and preferences. Taken together, changes occurring in these areas point to a rapidly transforming long-term care landscape. Financing responsibility is shifting away from the federal government to states, individuals, and their families; providers are integrating and managing acute and long-term care services and adding new services to the continuum of care; and consumers are thinking more seriously about how to plan and pay for their future care needs, as well as how to independently navigate the long-term care system.

Comment and response document for the long-term surveillance plan for the Bodo Canyon Disposal Site, Durango. Colorado

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

NONE

1996-07-01

This document contains comments made by the US Nuclear Regulatory Commission upon their review of the Long-Term Surveillance Plan for the Bodo Canyon Disposal Site, Durango, Colorado. Responses to the comments are also included in the document.

Long-term rise of the Water Table in the Northeast US: Climate Variability, Land-Use Change, or Angry Beavers?

NASA Astrophysics Data System (ADS)

Boutt, D. F.

2011-12-01

The scientific evidence that humans are directly influencing the Earth's natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research suggests that the Northeast region of the U.S. is experiencing significant changes to its' natural climate and hydrologic systems. Previous analysis of a long-term regional compilation of the water table response to the last 60 years of climate variability in New England documented a wide range of variability. The investigation evaluated the physical mechanisms, natural variability and response of aquifers in New England using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations. Groundwater trends were calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Interestingly, a trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most (80 out of 100) well sites. In this contribution we investigate the causal mechanisms behind the observed ground water level trends using site-by-site land-use change assessments, cluster analysis, and spatial analysis of beaver populations (a possible proxy for beaver activity). Regionally, average annual precipitation has been slightly increasing since 1900, with 95% of the stations having statistically significant positive trends. Despite this, no correlation is observed between the magnitude of the annual precipitation trends and the magnitude of the groundwater level changes. Land-use change throughout the region has primarily taken place in and around existing urban centers with an overall increase in the percentage of forested land. Individual analysis of well sites in areas with documented land-use change from agriculture and forested land cover to urban land use suggests a positive correlation with increasing water levels. Recently, beaver populations been begun to rise that has led to local increases in wetland areas. These regions also show a high positive correlation to the magnitude of water table rise. Local factors such as land-use change and beaver activity appear to overprint and mask the impact of consistent increases in annual precipitation. Rising water tables have major implications for not only water management but also the agriculture, forestry, fishing, and tourism industries as they all depend on the quantity and quality of water resources of the region.

Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

NASA Astrophysics Data System (ADS)

Nevalainen, Liisa; Rantala, Marttiina V.; Luoto, Tomi P.; Ojala, Antti E. K.; Rautio, Milla

2016-07-01

Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective pigmentation throughout the past centuries, elucidate the adaptive responses of zooplankton to long-term variations in UV exposure, and estimate the potential of fossil zooplankton pigments in reconstructing aquatic UV regimes. The spectroscopic absorbance measurements of fossil Daphnia ephippia under UV (280-400 nm) and visible light (400-700 nm) spectral ranges indicated that melanin (absorbance maxima at UV wavebands 280-350 nm) and carotenoids (absorbance maxima at 400-450 nm) pigments were preserved in the ephippia in both sediment cores. Downcore measurements of the most important UV-protective pigment melanin (absorbance measured at 305 and 340 nm) showed marked long-term variations in the degree of melanisation. These variations likely represented long-term trends in aquatic UV exposure and were positively related with solar radiation intensity. The corresponding trends in melanisation and solar activity were disrupted at the turn of the 20th century in R1, but remained as strong in Fugledammen. The reversed trends in the R1 core were simultaneous with a significant aquatic community reorganization taking place in the lake, suggesting that recent environmental changes, likely related to climate warming had a local effect on pigmentation strategies. This time horizon is also concurrent with previously recorded major ecological shifts in circumpolar lakes when human induced changes in ecological processes of sensitive arctic ecosystems started to occur. The current centennial record of UV-induced melanisation of sedimentary Daphnia ephippia presents unique reference material for assessing UV impacts in arctic aquatic ecosystems before human influence and during the 20th century climate change and provides potential for assessing past aquatic UV regimes.

Long-term variation of total ozone

NASA Astrophysics Data System (ADS)

Kane, R. P.

1988-03-01

The long-term variation of total ozone is studied for 1957 up to date for different latitude zones. The 3-year running averages show that, apart from a small portion showing parallelism with sunspot cycles, the trends in different latitude zones are dissimilar. In particular, where northern latitudes show a rising trend, the southern latitudes show an opposite (decreasing) trend. In the north-temperate group, Europe, North America and Asia show dissimilar trends. The longer data series (1932 ownards) for Arosa shows, besides a solar-cycle-dependent component, a steady level during 1932 1953 and a down-trend thereafter up to date. Very localised but long-lasting circulation patterns, different in different geographical regions, are indicated.

Long-term growth trends of red spruce and fraser fir at Mt. Rogers, Virginia and Mt. Mitchell, North Carolina

Treesearch

J.C.G. Goelz; Thomas E. Burk; Shepard M. Zedaker

1999-01-01

Cross-sectional area growth and height growth of Fraser fir and red spruce trees growing in Virginia and North Carolina were analyzed to identify possible long-term growth trends. Cross-sectional area growth provided no evidence of growth decline. The individual discs were classified according to parameter estimates of the growth trend equation. The predominant pattern...

Detecting long-term growth trends using tree rings: a critical evaluation of methods.

PubMed

Peters, Richard L; Groenendijk, Peter; Vlam, Mart; Zuidema, Pieter A

2015-05-01

Tree-ring analysis is often used to assess long-term trends in tree growth. A variety of growth-trend detection methods (GDMs) exist to disentangle age/size trends in growth from long-term growth changes. However, these detrending methods strongly differ in approach, with possible implications for their output. Here, we critically evaluate the consistency, sensitivity, reliability and accuracy of four most widely used GDMs: conservative detrending (CD) applies mathematical functions to correct for decreasing ring widths with age; basal area correction (BAC) transforms diameter into basal area growth; regional curve standardization (RCS) detrends individual tree-ring series using average age/size trends; and size class isolation (SCI) calculates growth trends within separate size classes. First, we evaluated whether these GDMs produce consistent results applied to an empirical tree-ring data set of Melia azedarach, a tropical tree species from Thailand. Three GDMs yielded similar results - a growth decline over time - but the widely used CD method did not detect any change. Second, we assessed the sensitivity (probability of correct growth-trend detection), reliability (100% minus probability of detecting false trends) and accuracy (whether the strength of imposed trends is correctly detected) of these GDMs, by applying them to simulated growth trajectories with different imposed trends: no trend, strong trends (-6% and +6% change per decade) and weak trends (-2%, +2%). All methods except CD, showed high sensitivity, reliability and accuracy to detect strong imposed trends. However, these were considerably lower in the weak or no-trend scenarios. BAC showed good sensitivity and accuracy, but low reliability, indicating uncertainty of trend detection using this method. Our study reveals that the choice of GDM influences results of growth-trend studies. We recommend applying multiple methods when analysing trends and encourage performing sensitivity and reliability analysis. Finally, we recommend SCI and RCS, as these methods showed highest reliability to detect long-term growth trends. © 2014 John Wiley & Sons Ltd.

Long-term pavement performance ancillary information management system (AIMS) reference guide.

DOT National Transportation Integrated Search

2012-11-01

This document provides information on the Long-Term Pavement Performance (LTPP) program ancillary information. : Ancillary information includes data, images, reference materials, resource documents, and other information that : support and extend the...

Long-term trends and variability of total and extreme precipitation in Thailand

NASA Astrophysics Data System (ADS)

Limsakul, Atsamon; Singhruck, Patama

2016-03-01

Based on quality-controlled daily station data, long-term trends and variability of total and extreme precipitation indices during 1955-2014 were examined for Thailand. An analysis showed that while precipitation events have been less frequent across most of Thailand, they have become more intense. Moreover, the indices measuring the magnitude of intense precipitation events indicate a trend toward wetter conditions, with heavy precipitation contributing a greater fraction to annual totals. One consequence of this change is the increased frequency and severity of flash floods as recently evidenced in many parts of Thailand. On interannual-to-interdecadal time scales, significant relationships between variability of precipitation indices and the indices for the state of El Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) were found. These results provide additional evidence that large-scale climate phenomena in the Pacific Ocean are remote drivers of variability in Thailand's total and extreme precipitation. Thailand tended to have greater amounts of precipitation and more extreme events during La Niña years and the PDO cool phase, and vice versa during El Niño years and the PDO warm phase. Another noteworthy finding is that in 2011 Thailand experienced extensive flooding in a year characterized by exceptionally extreme precipitation events. Our results are consistent with the regional studies for the Asia-Pacific Network. However, this study provides a more detailed picture of coherent trends at a station scale and documents changes that have occurred in the twenty-first century, both of which help to inform decisions concerning effective management strategies.

The Electrification of Energy: Long-Term Trends and Opportunities

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

Tsao, Jeffrey Y.; Fouquet, Roger; Schubert, E. Fred

Here, we present and analyze three powerful long-term historical trends in energy, particularly electrical energy, as well as the opportunities and challenges associated with these trends. The first trend is from a world containing a diversity of energy currencies to one whose predominant currency is electricity, driven by electricity’s transportability, exchangeability, and steadily decreasing cost. The second trend is from electricity generated from a diversity of sources to electricity generated predominantly by free-fuel sources, driven by their steadily decreasing cost and long-term abundance. These trends necessitate a just-emerging third trend: from a grid in which electricity is transported uni-directionally, tradedmore » at near-static prices, and consumed under direct human control; to a grid in which electricity is transported bi-directionally, traded at dynamic prices, and consumed under human-tailored agential control. Early acceptance and appreciation of these trends will accelerate their remaking of humanity’s energy landscape into one in which energy is much more affordable, abundant and efficiently deployed than it is today; with major economic, geo-political, and environmental benefits to human society.« less

Long-term trends in climate and hydrology in an agricultural, headwater watershed of central Pennsylvania, USA

USDA-ARS?s Scientific Manuscript database

Strategies to mitigate agricultural runoff must consider long-term changes in climate. We investigated temperature, precipitation and runoff trends over roughly four decades of monitoring an agricultural watershed in east central Pennsylvania (1968-2012). Temperature data confirmed significant expan...

Long-term trends in fire behavior and changes in population at risk

EPA Science Inventory

Long-term trends in fire behavior and changes in population at risk Rappold AG, Peterson GC, US EPA Matt Jolly, USFS Air pollution regulations and technological advances have successfully reduced emissions of air pollutants from many anthropogenic sources in recent decades. Duri...

Nitrate Trends in Minnesota Rivers

USGS Publications Warehouse

Wall, Dave; Christopherson, Dave; Lorenz, Dave; Martin, Gary

2013-01-01

The objective of this study was to assess long-term trends (30 to 35 years) of flow-adjusted concentrations of nitrite+nitrate-N (hereinafter referred to as nitrate) in a way that would allow us to discern changing trends. Recognizing that these trends are commonly different from one river to another river and from one part of the state to another, our objective was to examine as many river monitoring sites across the state as possible for which sufficient long term streamflow and concentration data were available.

Decadal and seasonal trends of nutrient concentration and export from highly managed coastal catchments.

PubMed

Wan, Yongshan; Wan, Lei; Li, Yuncong; Doering, Peter

2017-05-15

Understanding anthropogenic and hydro-climatic influences on nutrient concentrations and export from highly managed catchments often necessitates trend detection using long-term monitoring data. This study analyzed the temporal trend (1979-2014) of total nitrogen (TN) and total phosphorus (TP) concentrations and export from four adjacent coastal basins in south Florida where land and water resources are highly managed through an intricate canal network. The method of integrated seasonal-trend decomposition using LOESS (LOcally weighted regrESSion) was employed for trend detection. The results indicated that long-term trends in TN and TP concentrations (increasing/decreasing) varied with basins and nutrient species, reflecting the influence of basin specific land and water management practices. These long-term trends were intervened by short-term highs driven by high rainfall and discharges and lows associated with regional droughts. Seasonal variations in TP were more apparent than for TN. Nutrient export exhibited a chemostatic behavior for TN from all the basins, largely due to the biogenic nature of organic N associated with the ubiquity of organic materials in the managed canal network. Varying degrees of chemodynamic export was present for TP, reflecting complex biogeochemical responses to the legacy of long-term fertilization, low soil P holding capacity, and intensive stormwater management. The anthropogenic and hydro-climatic influences on nutrient concentration and export behavior had great implications in nutrient loading abatement strategies for aquatic ecosystem restoration of the downstream receiving waterbody. Published by Elsevier Ltd.

Comments on "Long-Term Variations of Exospheric Temperature Inferred From foF1 Observations: A Comparison to ISR Ti Trend Estimates" by Perrone and Mikhailov

NASA Astrophysics Data System (ADS)

Zhang, Shun-Rong; Holt, John M.; Erickson, Philip J.; Goncharenko, Larisa P.

2018-05-01

Perrone and Mikhailov (2017, https://doi.org/10.1002/2017JA024193) and Mikhailov et al. (2017, https://doi.org/10.1002/2017JA023909) have recently examined thermospheric and ionospheric long-term trends using a data set of four thermospheric parameters (Tex, [O], [N2], and [O2]) and solar EUV flux. These data were derived from one single ionospheric parameter, foF1, using a nonlinear fitting procedure involving a photochemical model for the F1 peak. The F1 peak is assumed at the transition height ht with the linear recombination for atomic oxygen ions being equal to the quadratic recombination for molecular ions. This procedure has a number of obvious problems that are not addressed or not sufficiently justified. The potentially large ambiguities and biases in derived parameters make them unsuitable for precise quantitative ionospheric and thermospheric long-term trend studies. Furthermore, we assert that Perrone and Mikhailov (2017, https://doi.org/10.1002/2017JA024193) conclusions regarding incoherent scatter radar (ISR) ion temperature analysis for long-term trend studies are incorrect and in particular are based on a misunderstanding of the nature of the incoherent scatter radar measurement process. Large ISR data sets remain a consistent and statistically robust method for determining long term secular plasma temperature trends.

Human Land-Use Practices Lead to Global Long-Term Increases in Photosynthetic Capacity

NASA Technical Reports Server (NTRS)

Mueller, Thomas; Tucker, Compton J.; Dressler, Gunnar; Pinzon, Jorge E.; Leimgruber, Peter; Dubayah, Ralph O.; Hurtt, George C.; Boehning-Gaese, Katrin; Fagan, William F.

2014-01-01

Long-term trends in photosynthetic capacity measured with the satellite-derived Normalized Difference Vegetation Index (NDVI) are usually associated with climate change. Human impacts on the global land surface are typically not accounted for. Here, we provide the first global analysis quantifying the effect of the earth's human footprint on NDVI trends. Globally, more than 20% of the variability in NDVI trends was explained by anthropogenic factors such as land use, nitrogen fertilization, and irrigation. Intensely used land classes, such as villages, showed the greatest rates of increase in NDVI, more than twice than those of forests. These findings reveal that factors beyond climate influence global long-term trends in NDVI and suggest that global climate change models and analyses of primary productivity should incorporate land use effects.

Global long-term ozone trends derived from different observed and modelled data sets

NASA Astrophysics Data System (ADS)

Coldewey-Egbers, M.; Loyola, D.; Zimmer, W.; van Roozendael, M.; Lerot, C.; Dameris, M.; Garny, H.; Braesicke, P.; Koukouli, M.; Balis, D.

2012-04-01

The long-term behaviour of stratospheric ozone amounts during the past three decades is investigated on a global scale using different observed and modelled data sets. Three European satellite sensors GOME/ERS-2, SCIAMACHY/ENVISAT, and GOME-2/METOP are combined and a merged global monthly mean total ozone product has been prepared using an inter-satellite calibration approach. The data set covers the 16-years period from June 1995 to June 2011 and it exhibits an excellent long-term stability, which is required for such trend studies. A multiple linear least-squares regression algorithm using different explanatory variables is applied to the time series and statistically significant positive trends are detected in the northern mid latitudes and subtropics. Global trends are also estimated using a second satellite-based Merged Ozone Data set (MOD) provided by NASA. For few selected geographical regions ozone trends are additionally calculated using well-maintained measurements of individual Dobson/Brewer ground-based instruments. A reasonable agreement in the spatial patterns of the trends is found amongst the European satellite, the NASA satellite, and the ground-based observations. Furthermore, two long-term simulations obtained with the Chemistry-Climate Models E39C-A provided by German Aerospace Center and UMUKCA-UCAM provided by University of Cambridge are analysed.

Adaptation of a Weighted Regression Approach to Evaluate Water Quality Trends in an Estuary

EPA Science Inventory

To improve the description of long-term changes in water quality, we adapted a weighted regression approach to analyze a long-term water quality dataset from Tampa Bay, Florida. The weighted regression approach, originally developed to resolve pollutant transport trends in rivers...

Gender-Based Violence in India: Long-Term Trends

ERIC Educational Resources Information Center

Simister, John; Mehta, Parnika S.

2010-01-01

This article examines long-term trends in Indian society regarding domestic violence between husband and wife, and attitudes to such violence. This article analyzes crime data and uses data from several Indian household surveys: "Work Attitudes and Spending" surveys (1992 to 2007); "World Values Survey" (1990, 1995, 2001, and…

Adaptation of a weighted regression approach to evaluate water quality trends in anestuary

EPA Science Inventory

To improve the description of long-term changes in water quality, a weighted regression approach developed to describe trends in pollutant transport in rivers was adapted to analyze a long-term water quality dataset from Tampa Bay, Florida. The weighted regression approach allows...

Childhood health: trends and consequences over the life course.

PubMed

Delaney, Liam; Smith, James P

2012-01-01

This article first documents evidence on the changing prevalence of childhood physical and mental health problems, focusing on the development of childhood health conditions in the United States. Authors Liam Delaney and James Smith present evidence on the changing prevalence of childhood chronic conditions over time using recalled data as well as contemporaneous accounts of these childhood health problems. The raw data from both sources show sharp increases in the prevalence of most childhood physical health problems (such as asthma, allergies, respiratory problems, and migraines) over time. However, inferring trends is difficult because such data are also consistent with improved detection of childhood disease, and many of the causes of childhood disease have not worsened over time. Conclusions about rapidly rising rates of childhood physical health problems over time are premature at best, especially concerning the magnitude of trends. Documenting real changes in the prevalence of specific diseases is a high-priority research topic. In contrast, the evidence is much stronger that childhood mental health problems are becoming worse. The authors next present new evidence on the effects of early childhood physical and mental problems on health and economic status in adulthood. They find that both childhood physical and mental health problems contribute significantly to poorer adult health. However, they also find that childhood mental health problems have much larger impacts than do childhood physical health problems on four critical areas of socioeconomic status as an adult: education, weeks worked per year, individual earnings, and family income. Finally, the authors examine evidence regarding the efficacy of early mental health treatment for children in terms of promoting good health later on. Existing studies suggest that a combination of cognitive behavioral therapy and medication appears to be effective in the treatment of both anxiety and depression in children. However, much more research is needed on the efficacy of these childhood interventions into adulthood. Clinical trials have been too short to evaluate the long-term impacts of various forms of treatment, and these impacts are definitively long term.

Zeitgeists and development trends in long-term care facility design.

PubMed

Wang, Chia-Hui; Kuo, Nai-Wen

2006-06-01

Through literature analysis, in-depth interviews, and the application of the Delphi survey, this study explored long-term care resident priorities with regard to long-term care facility design in terms of both physical and psychological needs. This study further clarified changing trends in long-term care concepts; illustrated the impact that such changes are having on long-term care facility design; and summarized zeitgeists related to the architectural design of long-term care facilities. Results of our Delphi survey indicated the following top five priorities in long-term care facility design: (1) creating a home-like feeling; (2) adhering to Universal Design concepts; (3) providing well-defined private sleeping areas; (4) providing adequate social space; and (5) decentralizing residents' rooms into clusters. The three major zeitgeists related to long-term care facility design include: (1) modern long-term care facilities should abandon their traditional "hospital" image and gradually reposition facilities into homelike settings; (2) institution-based care for the elderly should be de-institutionalized under the concept of aging-in-place; and (3) living clusters, rather than traditional hospital-like wards, should be designed into long-term care facilities.

Long-term temporal and spatial trends in eutrophication status of the Baltic Sea.

PubMed

Andersen, Jesper H; Carstensen, Jacob; Conley, Daniel J; Dromph, Karsten; Fleming-Lehtinen, Vivi; Gustafsson, Bo G; Josefson, Alf B; Norkko, Alf; Villnäs, Anna; Murray, Ciarán

2017-02-01

Much of the Baltic Sea is currently classified as 'affected by eutrophication'. The causes for this are twofold. First, current levels of nutrient inputs (nitrogen and phosphorus) from human activities exceed the natural processing capacity with an accumulation of nutrients in the Baltic Sea over the last 50-100 years. Secondly, the Baltic Sea is naturally susceptible to nutrient enrichment due to a combination of long retention times and stratification restricting ventilation of deep waters. Here, based on a unique data set collated from research activities and long-term monitoring programs, we report on the temporal and spatial trends of eutrophication status for the open Baltic Sea over a 112-year period using the HELCOM Eutrophication Assessment Tool (HEAT 3.0). Further, we analyse variation in the confidence of the eutrophication status assessment based on a systematic quantitative approach using coefficients of variation in the observations. The classifications in our assessment indicate that the first signs of eutrophication emerged in the mid-1950s and the central parts of the Baltic Sea changed from being unaffected by eutrophication to being affected. We document improvements in eutrophication status that are direct consequences of long-term efforts to reduce the inputs of nutrients. The reductions in both nitrogen and phosphorus loads have led to large-scale alleviation of eutrophication and to a healthier Baltic Sea. Reduced confidence in our assessment is seen more recently due to reductions in the scope of monitoring programs. Our study sets a baseline for implementation of the ecosystem-based management strategies and policies currently in place including the EU Marine Strategy Framework Directives and the HELCOM Baltic Sea Action Plan. © 2015 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.

Group Health’s Initiative To Avert Opioid Misuse And Overdose Among Patients With Chronic Noncancer Pain

PubMed Central

Trescott, Claire E.; Beck, Randi M.; Seelig, Michelle D.; Von Korff, Michael R.

2012-01-01

Increased opioid prescribing for chronic pain that is not due to cancer has been accompanied by large increases in abuse and overdose of prescription opioids. This paper describes how Group Health, a Seattle-based nonprofit health care system, implemented a major initiative to make opioid prescribing safer. In the initiative’s first nine months, clinicians developed documented care plans for almost 6,000 patients receiving long-term opioid therapy for chronic pain. Evaluation of the initiative’s effects on care processes and trends in adverse events is under way. PMID:21821559

Some Trends and Reforms in the Educational Policy of Norway in the Light of the Concept of Life-Long Education.

ERIC Educational Resources Information Center

Udjus, Ingelise

An emphasis on planned and completed educational reforms in Norway which reflect the attitude that education is a lifelong process is presented in this document. A study is made of some of the trends in the development of the formal school system which have been influenced by the concept of life-long education. This study includes primary,…

Continent-scale global change attribution in European birds - combining annual and decadal time scales.

PubMed

Jørgensen, Peter Søgaard; Böhning-Gaese, Katrin; Thorup, Kasper; Tøttrup, Anders P; Chylarecki, Przemysław; Jiguet, Frédéric; Lehikoinen, Aleksi; Noble, David G; Reif, Jiri; Schmid, Hans; van Turnhout, Chris; Burfield, Ian J; Foppen, Ruud; Voříšek, Petr; van Strien, Arco; Gregory, Richard D; Rahbek, Carsten

2016-02-01

Species attributes are commonly used to infer impacts of environmental change on multiyear species trends, e.g. decadal changes in population size. However, by themselves attributes are of limited value in global change attribution since they do not measure the changing environment. A broader foundation for attributing species responses to global change may be achieved by complementing an attributes-based approach by one estimating the relationship between repeated measures of organismal and environmental changes over short time scales. To assess the benefit of this multiscale perspective, we investigate the recent impact of multiple environmental changes on European farmland birds, here focusing on climate change and land use change. We analyze more than 800 time series from 18 countries spanning the past two decades. Analysis of long-term population growth rates documents simultaneous responses that can be attributed to both climate change and land-use change, including long-term increases in populations of hot-dwelling species and declines in long-distance migrants and farmland specialists. In contrast, analysis of annual growth rates yield novel insights into the potential mechanisms driving long-term climate induced change. In particular, we find that birds are affected by winter, spring, and summer conditions depending on the distinct breeding phenology that corresponds to their migratory strategy. Birds in general benefit from higher temperatures or higher primary productivity early on or in the peak of the breeding season with the largest effect sizes observed in cooler parts of species' climatic ranges. Our results document the potential of combining time scales and integrating both species attributes and environmental variables for global change attribution. We suggest such an approach will be of general use when high-resolution time series are available in large-scale biodiversity surveys. © 2015 John Wiley & Sons Ltd.

Long-term trend analysis on total and extreme precipitation over Shasta Dam watershed.

PubMed

Toride, Kinya; Cawthorne, Dylan L; Ishida, Kei; Kavvas, M Levent; Anderson, Michael L

2018-06-01

California's interconnected water system is one of the most advanced water management systems in the world, and understanding of long-term trends in atmospheric and hydrologic behavior has increasingly being seen as vital to its future well-being. Knowledge of such trends is hampered by the lack of long-period observation data and the uncertainty surrounding future projections of atmospheric models. This study examines historical precipitation trends over the Shasta Dam watershed (SDW), which lies upstream of one of the most important components of California's water system, Shasta Dam, using a dynamical downscaling methodology that can produce atmospheric data at fine time-space scales. The Weather Research and Forecasting (WRF) model is employed to reconstruct 159years of long-term hourly precipitation data at 3km spatial resolution over SDW using the 20th Century Reanalysis Version 2c dataset. Trend analysis on this data indicates a significant increase in total precipitation as well as a growing intensity of extreme events such as 1, 6, 12, 24, 48, and 72-hour storms over the period of 1851 to 2010. The turning point of the increasing trend and no significant trend periods is found to be 1940 for annual precipitation and the period of 1950 to 1960 for extreme precipitation using the sequential Mann-Kendall test. Based on these analysis, we find the trends at the regional scale do not necessarily apply to the watershed-scale. The sharp increase in the variability of annual precipitation since 1970s is also detected, which implies an increase in the occurrence of extreme wet and dry conditions. These results inform long-term planning decisions regarding the future of Shasta Dam and California's water system. Copyright © 2018 Elsevier B.V. All rights reserved.

Long-term trends from ecosystem research at the Hubbard Brook Experimental Forest

Treesearch

John L. Campbell; Charles T. Driscoll; Christopher Eagar; Gene E. Likens; Thomas G. Siccama; Chris E. Johnson; Timothy J. Fahey; Steven P. Hamburg; Richard T. Holmes; Amey S. Bailey; Donald C. Buso

2007-01-01

Summarizes 52 years of collaborative, long-term research conducted at the Hubbard Brook (NH) Experimental Forest on ecosystem response to disturbances such as air pollution, climate change, forest disturbance, and forest management practices. Also provides explanations of some of the trends and lists references from scientific literature for further reading.

Long-Term Use of Benzodiazepines and Nonbenzodiazepine Hypnotics, 1999-2014.

PubMed

Kaufmann, Christopher N; Spira, Adam P; Depp, Colin A; Mojtabai, Ramin

2018-02-01

Clinical guidelines suggest that benzodiazepines (BZDs) and non-BZD hypnotics (NBHs) be used on a short-term basis. The authors examined trends in long-term BZD and NBH use from 1999 to 2014. Data included 82,091 respondents in the 1999-2014 waves of the National Health and Nutrition Examination Survey (NHANES). NHANES recorded medications used in the past 30 days on the basis of prescription bottles, and participants reported use duration. BZD and NBH use were categorized as short, medium, and long term, and time trends in use were assessed. BZD and NBH use increased from 1999 to 2014, driven by increases in medium- and long-term use, even after adjustment for age and race-ethnicity. In most years, only a fifth of current BZD or NBH users reported short-term use. Long-term BZD and NBH use has grown independent of U.S. demographic shifts. Monitoring of use is needed to prevent adverse outcomes.

Endovascular Stent Treatment for Symptomatic Benign Iliofemoral Venous Occlusive Disease: Long-Term Results 1987-2009

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

Gutzeit, A., E-mail: andreas.gutzeit@ksw.ch; Zollikofer, Ch. L., E-mail: Christoph.Zollikofer@ksb.ch; Dettling-Pizzolato, M., E-mail: Mira.Dettling@ksw.ch

Venous stenting has been shown to effectively treat iliofemoral venous obstruction with good short- and mid-term results. The aim of this study was to investigate long-term clinical outcome and stent patency. Twenty patients were treated with venous stenting for benign disease at our institution between 1987 and 2005. Fifteen of 20 patients (15 female, mean age at time of stent implantation 38 years [range 18-66]) returned for a clinical visit, a plain X-ray of the stent, and a Duplex ultrasound. Four patients were lost to follow-up, and one patient died 277 months after stent placement although a good clinical resultmore » was documented 267 months after stent placement. Mean follow-up after stent placement was 167.8 months (13.9 years) (range 71 (6 years) to 267 months [22 years]). No patient needed an additional venous intervention after stent implantation. No significant difference between the circumference of the thigh on the stented side (mean 55.1 cm [range 47.0-70.0]) compared with the contralateral thigh (mean 54.9 cm [range 47.0-70.0]) (p = 0.684) was seen. There was a nonsignificant trend toward higher flow velocities within the stent (mean 30.8 cm/s [range 10.0-48.0]) and the corresponding vein segment on the contralateral side (mean 25.2 cm/s [range 12.0-47.0]) (p = 0.065). Stent integrity was confirmed in 14 of 15 cases. Only one stent showed a fracture, as documented on x-ray, without any impairment of flow. Venous stenting using Wallstents showed excellent long-term clinical outcome and primary patency rate.« less

Long-Term Economic and Labor Forecast Trends for Washington. 1996.

ERIC Educational Resources Information Center

Lefberg, Irv; And Others

This publication provides actual historical and long-term forecast data on labor force, total wage and salary employment, industry employment, and personal income for the state of Washington. The data are based upon the Washington Office of Financial Management long-term population forecast. Chapter 1 presents long-term forecasts of Washington…

Coral proxy record of decadal-scale reduction in base flow from Moloka'i, Hawaii

USGS Publications Warehouse

Prouty, Nancy G.; Jupiter, Stacy D.; Field, Michael E.; McCulloch, Malcolm T.

2009-01-01

Groundwater is a major resource in Hawaii and is the principal source of water for municipal, agricultural, and industrial use. With a growing population, a long-term downward trend in rainfall, and the need for proper groundwater management, a better understanding of the hydroclimatological system is essential. Proxy records from corals can supplement long-term observational networks, offering an accessible source of hydrologic and climate information. To develop a qualitative proxy for historic groundwater discharge to coastal waters, a suite of rare earth elements and yttrium (REYs) were analyzed from coral cores collected along the south shore of Moloka'i, Hawaii. The coral REY to calcium (Ca) ratios were evaluated against hydrological parameters, yielding the strongest relationship to base flow. Dissolution of REYs from labradorite and olivine in the basaltic rock aquifers is likely the primary source of coastal ocean REYs. There was a statistically significant downward trend (−40%) in subannually resolved REY/Ca ratios over the last century. This is consistent with long-term records of stream discharge from Moloka'i, which imply a downward trend in base flow since 1913. A decrease in base flow is observed statewide, consistent with the long-term downward trend in annual rainfall over much of the state. With greater demands on freshwater resources, it is appropriate for withdrawal scenarios to consider long-term trends and short-term climate variability. It is possible that coral paleohydrological records can be used to conduct model-data comparisons in groundwater flow models used to simulate changes in groundwater level and coastal discharge.

Multidecadal warming of Antarctic waters.

PubMed

Schmidtko, Sunke; Heywood, Karen J; Thompson, Andrew F; Aoki, Shigeru

2014-12-05

Decadal trends in the properties of seawater adjacent to Antarctica are poorly known, and the mechanisms responsible for such changes are uncertain. Antarctic ice sheet mass loss is largely driven by ice shelf basal melt, which is influenced by ocean-ice interactions and has been correlated with Antarctic Continental Shelf Bottom Water (ASBW) temperature. We document the spatial distribution of long-term large-scale trends in temperature, salinity, and core depth over the Antarctic continental shelf and slope. Warming at the seabed in the Bellingshausen and Amundsen seas is linked to increased heat content and to a shoaling of the mid-depth temperature maximum over the continental slope, allowing warmer, saltier water greater access to the shelf in recent years. Regions of ASBW warming are those exhibiting increased ice shelf melt. Copyright © 2014, American Association for the Advancement of Science.

Microclimate Exposures of Surface-Based Weather Stations: Implications For The Assessment of Long-Term Temperature Trends.

NASA Astrophysics Data System (ADS)

Davey, Christopher A.; Pielke, Roger A., Sr.

2005-04-01

The U.S. Historical Climate Network is a subset of surface weather observation stations selected from the National Weather Service cooperative station network. The criteria used to select these stations do not sufficiently address station exposure characteristics. In addition, the current metadata available for cooperative network stations generally do not describe site exposure characteristics in sufficient detail. This paper focuses on site exposures with respect to air temperature measurements. A total of 57 stations were photographically surveyed in eastern Colorado, comparing existing exposures to the standards endorsed by the World Meteorological Organization. The exposures of most sites surveyed, including U.S. Historical Climate Network sites, were observed to fall short of these standards. This raises a critical question about the use of many Historical Climate Network sites in the development of long-term climate records and the detection of climate trends. Some of these sites clearly have poor exposures and therefore should be considered for removal from the Historical Climate Network. Candidate replacement sites do exist and should be considered for addition into the network to replace the removed sites. Documentation as performed for this study should be conducted worldwide in order to determine the extent of spatially nonrepresentative exposures and possible temperature biases.

Long-term pavement performance maintenance and rehabilitation data collection guide

DOT National Transportation Integrated Search

2006-03-01

This document provides guidelines and forms for documenting maintenance and rehabilitation treatments on test sections in the Long-Term Pavement Performance (LTPP) program and is an update to chapters 6 and 7 of the 1993 version of the LTPP Data Coll...

Long-term forest resilience to climate change indicated by mortality, regeneration, and growth in semiarid southern Siberia.

PubMed

Xu, Chongyang; Liu, Hongyan; Anenkhonov, Oleg A; Korolyuk, Andrey Yu; Sandanov, Denis V; Balsanova, Larisa D; Naidanov, Bulat B; Wu, Xiuchen

2017-06-01

Several studies have documented that regional climate warming and the resulting increase in drought stress have triggered increased tree mortality in semiarid forests with unavoidable impacts on regional and global carbon sequestration. Although climate warming is projected to continue into the future, studies examining long-term resilience of semiarid forests against climate change are limited. In this study, long-term forest resilience was defined as the capacity of forest recruitment to compensate for losses from mortality. We observed an obvious change in long-term forest resilience along a local aridity gradient by reconstructing tree growth trend and disturbance history and investigating postdisturbance regeneration in semiarid forests in southern Siberia. In our study, with increased severity of local aridity, forests became vulnerable to drought stress, and regeneration first accelerated and then ceased. Radial growth of trees during 1900-2012 was also relatively stable on the moderately arid site. Furthermore, we found that smaller forest patches always have relatively weaker resilience under the same climatic conditions. Our results imply a relatively higher resilience in arid timberline forest patches than in continuous forests; however, further climate warming and increased drought could possibly cause the disappearance of small forest patches around the arid tree line. This study sheds light on climate change adaptation and provides insight into managing vulnerable semiarid forests. © 2016 John Wiley & Sons Ltd.

User guide to Exploration and Graphics for RivEr Trends (EGRET) and dataRetrieval: R packages for hydrologic data

USGS Publications Warehouse

Hirsch, Robert M.; De Cicco, Laura A.

2015-01-01

Evaluating long-term changes in river conditions (water quality and discharge) is an important use of hydrologic data. To carry out such evaluations, the hydrologist needs tools to facilitate several key steps in the process: acquiring the data records from a variety of sources, structuring it in ways that facilitate the analysis, processing the data with routines that extract information about changes that may be happening, and displaying findings with graphical techniques. A pair of tightly linked R packages, called dataRetrieval and EGRET (Exploration and Graphics for RivEr Trends), have been developed for carrying out each of these steps in an integrated manner. They are designed to easily accept data from three sources: U.S. Geological Survey hydrologic data, U.S. Environmental Protection Agency (EPA) STORET data, and user-supplied flat files. The dataRetrieval package not only serves as a “front end” to the EGRET package, it can also be used to easily download many types of hydrologic data and organize it in ways that facilitate many other hydrologic applications. The EGRET package has components oriented towards the description of long-term changes in streamflow statistics (high flow, average flow, and low flow) as well as changes in water quality. For the water-quality analysis, it uses Weighted Regressions on Time, Discharge and Season (WRTDS) to describe long-term trends in both concentration and flux. EGRET also creates a wide range of graphical presentations of the water-quality data and of the WRTDS results. This report serves as a user guide to these two R packages, providing detailed guidance on installation and use of the software, documentation of the analysis methods used, as well as guidance on some of the kinds of questions and approaches that the software can facilitate.

Analysis of the Arctic system for freshwater cycle intensification: Observations and expectations

USGS Publications Warehouse

Rawlins, M.A.; Steele, M.; Holland, M.M.; Adam, J.C.; Cherry, J.E.; Francis, J.A.; Groisman, P.Y.; Hinzman, L.D.; Huntington, T.G.; Kane, D.L.; Kimball, J.S.; Kwok, R.; Lammers, R.B.; Lee, C.M.; Lettenmaier, D.P.; McDonald, K.C.; Podest, E.; Pundsack, J.W.; Rudels, B.; Serreze, Mark C.; Shiklomanov, A.; Skagseth, O.; Troy, T.J.; Vorosmarty, C.J.; Wensnahan, M.; Wood, E.F.; Woodgate, R.; Yang, D.; Zhang, K.; Zhang, T.

2010-01-01

Hydrologic cycle intensification is an expected manifestation of a warming climate. Although positive trends in several global average quantities have been reported, no previous studies have documented broad intensification across elements of the Arctic freshwater cycle (FWC). In this study, the authors examine the character and quantitative significance of changes in annual precipitation, evapotranspiration, and river discharge across the terrestrial pan-Arctic over the past several decades from observations and a suite of coupled general circulation models (GCMs). Trends in freshwater flux and storage derived from observations across the Arctic Ocean and surrounding seas are also described. With few exceptions, precipitation, evapotranspiration, and river discharge fluxes from observations and the GCMs exhibit positive trends. Significant positive trends above the 90% confidence level, however, are not present for all of the observations. Greater confidence in the GCM trends arises through lower interannual variability relative to trend magnitude. Put another way, intrinsic variability in the observations tends to limit confidence in trend robustness. Ocean fluxes are less certain, primarily because of the lack of long-term observations. Where available, salinity and volume flux data suggest some decrease in saltwater inflow to the Barents Sea (i.e., a decrease in freshwater outflow) in recent decades. A decline in freshwater storage across the central Arctic Ocean and suggestions that large-scale circulation plays a dominant role in freshwater trends raise questions as to whether Arctic Ocean freshwater flows are intensifying. Although oceanic fluxes of freshwater are highly variable and consistent trends are difficult to verify, the other components of the Arctic FWC do show consistent positive trends over recent decades. The broad-scale increases provide evidence that the Arctic FWC is experiencing intensification. Efforts that aim to develop an adequate observation system are needed to reduce uncertainties and to detect and document ongoing changes in all system components for further evidence of Arctic FWC intensification.

Do climate model predictions agree with long-term precipitation trends in the arid southwestern United States?

NASA Astrophysics Data System (ADS)

Elias, E.; Rango, A.; James, D.; Maxwell, C.; Anderson, J.; Abatzoglou, J. T.

2016-12-01

Researchers evaluating climate projections across southwestern North America observed a decreasing precipitation trend. Aridification was most pronounced in the cold (non-monsoonal) season, whereas downward trends in precipitation were smaller in the warm (monsoonal) season. In this region, based upon a multimodel mean of 20 Coupled Model Intercomparison Project 5 models using a business-as-usual (Representative Concentration Pathway 8.5) trajectory, midcentury precipitation is projected to increase slightly during the monsoonal time period (July-September; 6%) and decrease slightly during the remainder of the year (October-June; -4%). We use observed long-term (1915-2015) monthly precipitation records from 16 weather stations to investigate how well measured trends corroborate climate model predictions during the monsoonal and non-monsoonal timeframe. Running trend analysis using the Mann-Kendall test for 15 to 101 year moving windows reveals that half the stations showed significant (p≤0.1), albeit small, increasing trends based on the longest term record. Trends based on shorter-term records reveal a period of significant precipitation decline at all stations representing the 1950s drought. Trends from 1930 to 2015 reveal significant annual, monsoonal and non-monsoonal increases in precipitation (Fig 1). The 1960 to 2015 time window shows no significant precipitation trends. The more recent time window (1980 to 2015) shows a slight, but not significant, increase in monsoonal precipitation and a larger, significant decline in non-monsoonal precipitation. GCM precipitation projections are consistent with more recent trends for the region. Running trends from the most recent time window (mid-1990s to 2015) at all stations show increasing monsoonal precipitation and decreasing Oct-Jun precipitation, with significant trends at 6 of 16 stations. Running trend analysis revealed that the long-term trends were not persistent throughout the series length, but depended on the period examined. Recent trends in Southwest precipitation are directionally consistent with anthropogenic climate change.

Cohort Measures of Internal Migration: Understanding Long-Term Trends.

PubMed

Bernard, Aude

2017-12-01

Internal migration intensities fluctuate over time, but both migration levels and trends show great diversity. The dynamics underpinning these trends remain poorly understood because they are analyzed almost exclusively by applying period measures to cross-sectional data. This article proposes 10 cohort measures that can be applied to both prospective and retrospective data to systematically examine long-term trends. To demonstrate their benefits, the proposed measures are applied to retrospective survey data for England that provide residential histories from birth to age 50 for cohorts born between 1918 and 1957. The analysis reveals stable lifetime migration for men but increased lifetime migration for women associated with earlier ages at moving in adulthood and a compression of intervals between consecutive moves. The proposed cohort measures provide a more comprehensive picture of migration behavior and should be used to complement period measures in exploring long-term trends. Increasing availability of retrospective and longitudinal survey data means that researchers can now apply the proposed measures to a wide range of countries.

Recreational physical activity and risk of papillary thyroid cancer among women in the California Teachers Study

PubMed Central

Cash, Stephanie Whisnant; Ma, Huiyan; Horn-Ross, Pamela L.; Reynolds, Peggy; Canchola, Alison J.; Sullivan-Halley, Jane; Beresford, Shirley A.A.; Neuhouser, Marian L.; Vaughan, Thomas L.; Heagerty, Patrick J.; Bernstein, Leslie

2012-01-01

Purpose Little is known about the relationship between physical activity and thyroid cancer risk, and few cohort data on this association exist. Thus, the present study aimed to prospectively examine long-term activity and risk of papillary thyroid cancer among women. Methods 116,939 women in the California Teachers Study, aged 22 to 79 years with no history of thyroid cancer at cohort entry, were followed from 1995-1996 through 2009; 275 were diagnosed with invasive papillary thyroid cancer. Cox proportional-hazards regression provided relative risk (RR) estimates and 95% confidence intervals (CI) for associations between thyroid cancer and combined strenuous and moderate recreational physical activity both in the long-term (high school through age 54 years or current age if younger than 54 years) and recently (during the three years prior to joining the cohort). Results Overall, women whose long-term recreational physical activity averaged at least 5.5 MET-hours/week (i.e. were active) had a non-significant 23% lower risk of papillary thyroid cancer than inactive women (RR=0.77, 95% CI: 0.57, 1.04). RR estimates were stronger among normal weight or underweight women (body mass index, BMI<25.0 kg/m2, trend p=0.03) than among overweight or obese women (trend p=0.35; homogeneity-of-trends p=0.03). A similar pattern of risk was observed for recent activity (BMI<25 kg/m2, trend p=0.11; BMI≥25 kg/m2, trend p=0.16; homogeneity-of-trends p=0.04). Associations for long-term activity did not appear to be driven by activity in any particular life period (e.g. youth, adulthood). Conclusions Long-term physical activity may reduce papillary thyroid cancer risk among normal weight and underweight women. PMID:23116823

Long-term trends in climate and hydrology in an agricultural headwater watershed of central Pennsylvania, USA

USDA-ARS?s Scientific Manuscript database

Climate change has emerged as a key issue facing agriculture and water resources in the US. Long-term (1968-2012) temperature, precipitation and streamflow data from a small (7.3 km2) watershed in east-central Pennsylvania was used to examine climatic and hydrologic trends in the context of recent c...

Assessment of the effects of horizontal grid resolution on long-term air quality trends using coupled WRF-CMAQ simulations

EPA Science Inventory

The objective of this study is to determine the adequacy of using a relatively coarse horizontal resolution (i.e. 36 km) to simulate long-term trends of pollutant concentrations and radiation variables with the coupled WRF-CMAQ model. WRF-CMAQ simulations over the continental Uni...

Long-term trends in height growth of jack pine in North Central Ontario

Treesearch

J.C.G. Goelz; T.E. Burk

1998-01-01

Although most investigations of long-term growth trends of trees involve description of radial growth of trees, investigation of height growth of dominant and codominant trees also warrants attention for two significant reasons -- the dependent variable is largely independent of stand density and it represents an index of stand productivity. Residuals from a height...

Trends in Mortality of Tuberculosis Patients in the United States: The Long-term Perspective

PubMed Central

Barnes, Richard F.W.; Moore, Maria Luisa; Garfein, Richard S.; Brodine, Stephanie; Strathdee, Steffanie A.; Rodwell, Timothy C.

2011-01-01

PURPOSE To describe long-term trends in TB mortality and to compare trends estimated from two different sources of public health surveillance data. METHODS Trends and changes in trend were estimated by joinpoint regression. Comparisons between datasets were made by fitting a Poisson regression model. RESULTS Since 1900, TB mortality rates estimated from death certificates have declined steeply, except for a period of no change in the 1980s. This decade had long-term consequences resulting in more TB deaths in later years than would have occurred had there been no flattening of the trend. Recent trends in TB mortality estimated from National Tuberculosis Surveillance System (NTSS) data, which record all-cause mortality, differed from trends based on death certificates. In particular, NTSS data showed TB mortality rates flattening since 2002. CONCLUSIONS Estimates of trends in TB mortality vary by data source, and therefore interpretation of the success of control efforts will depend upon the surveillance dataset used. The datasets may be subject to different biases that vary with time. One dataset showed a sustained improvement in the control of TB since the early 1990s while the other indicated that the rate of TB mortality was no longer declining. PMID:21820320

Long-Term Trends in Space-Ground Atmospheric Propagation Measurements

NASA Technical Reports Server (NTRS)

Zemba, Michael J.; Nessel, James A.; Morse, Jacquelynne R.

2015-01-01

Propagation measurement campaigns are critical to characterizing the atmospheric behavior of a location and efficiently designing space-ground links. However, as global climate change affects weather patterns, the long-term trends of propagation data may be impacted over periods of decades or longer. Particularly, at high microwave frequencies (10 GHz and above), rain plays a dominant role in the attenuation statistics, and it has been observed that rain events over the past 50 years have trended toward increased frequency, intensity, and rain height. In the interest of quantifying the impact of these phenomena on long-term trends in propagation data, this paper compares two 20 GHz measurement campaigns both conducted at NASAs White Sands facility in New Mexico. The first is from the Advanced Communications Technology Satellite (ACTS) propagation campaign from 1994 to 1998, while the second is amplitude data recorded during a site test interferometer (STI) phase characterization campaign from 2009 to 2014.

Long-Term Trends in Space-Ground Atmospheric Propagation Measurements

NASA Technical Reports Server (NTRS)

Zemba, Michael J.; Morse, Jacquelynne R.; Nessel, James A.

2015-01-01

Propagation measurement campaigns are critical to characterizing the atmospheric behavior of a location and efficiently designing space-ground links. However, as global climate change affects weather patterns, the long-term trends of propagation data may be impacted over periods of decades or longer. Particularly, at high microwave frequencies (10 GHz and above), rain plays a dominant role in the attenuation statistics, and it has been observed that rain events over the past 50 years have trended toward increased frequency, intensity, and rain height. In the interest of quantifying the impact of these phenomena on long-term trends in propagation data, this paper compares two 20 GHz measurement campaigns both conducted at NASA's White Sands facility in New Mexico. The first is from the Advanced Communication Technology Satellite (ACTS) propagation campaign from 1994 - 1998, while the second is amplitude data recorded during a site test interferometer (STI) phase characterization campaign from 2009 - 2014.

Long-term exposure of Mytilus galloprovincialis to diclofenac, Ibuprofen and Ketoprofen: Insights into bioavailability, biomarkers and transcriptomic changes.

PubMed

Mezzelani, M; Gorbi, S; Fattorini, D; d'Errico, G; Consolandi, G; Milan, M; Bargelloni, L; Regoli, F

2018-05-01

Non-steroidal anti-inflammatory drugs (NSAIDs) represent a growing concern for marine ecosystems due to their ubiquitous occurrence and documented adverse effects on non-target organisms. Despite the remarkable efforts to elucidate bioaccumulation and ecotoxicological potential under short-term conditions, limited and fragmentary information is available for chronic exposures. In this study bioavailability, molecular and cellular effects of diclofenac (DIC), ibuprofen (IBU) and ketoprofen (KET) were investigated in mussels Mytilus galloprovincialis exposed to the realistic environmental concentration of 2.5 μg/L for up to 60 days. Results indicated a significant accumulation of DIC and IBU but without a clear time-dependent trend; on the other hand, KET concentrations were always below the detection limit. Analyses of a large panel of molecular, biochemical and cellular biomarkers highlighted that all investigated NSAIDs caused alterations of immunological parameters, genotoxic effects, modulation of lipid metabolism and changes in cellular turn-over. This study provided the evidence of long-term ecotoxicological potential of NSAIDs, further unraveling the possible hazard for wild marine organisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

Detecting Long-term Trend of Water Quality Indices of Dong-gang River, Taiwan Using Quantile Regression

NASA Astrophysics Data System (ADS)

Yang, D.; Shiau, J.

2013-12-01

ABSTRACT BODY: Abstract Surface water quality is an essential issue in water-supply for human uses and sustaining healthy ecosystem of rivers. However, water quality of rivers is easily influenced by anthropogenic activities such as urban development and wastewater disposal. Long-term monitoring of water quality can assess whether water quality of rivers deteriorates or not. Taiwan is a population-dense area and heavily depends on surface water for domestic, industrial, and agricultural uses. Dong-gang River is one of major resources in southern Taiwan for agricultural requirements. The water-quality data of four monitoring stations of the Dong-gang River for the period of 2000-2012 are selected for trend analysis. The parameters used to characterize water quality of rivers include biochemical oxygen demand (BOD), dissolved oxygen (DO), suspended solids (SS), and ammonia nitrogen (NH3-N). These four water-quality parameters are integrated into an index called river pollution index (RPI) to indicate the pollution level of rivers. Although widely used non-parametric Mann-Kendall test and linear regression exhibit computational efficiency to identify trends of water-quality indices, limitations of such approaches include sensitive to outliers and estimations of conditional mean only. Quantile regression, capable of identifying changes over time of any percentile values, is employed in this study to detect long-term trend of water-quality indices for the Dong-gang River located in southern Taiwan. The results show that Dong-gang River 4 stations from 2000 to 2012 monthly long-term trends in water quality.To analyze s Dong-gang River long-term water quality trends and pollution characteristics. The results showed that the bridge measuring ammonia Long-dong, BOD5 measure in that station on a downward trend, DO, and SS is on the rise, River Pollution Index (RPI) on a downward trend. The results form Chau-Jhou station also ahowed simialar trends .more and more near the upstrean Hing-she station raise vivestok Sing-She stations are that ammonia on a upward trend, BOD5 no significant change in trend, DO, and SS is on the rise, river pollution index (RPI) a slight downward trend. Dong-gang River Basin , but the progress of sewer construction in slow. To reduce pollation in this river effort shoul be made regulatory reform on livestock waste control and acceleration of sewer construction. Keywords: quantile regression analysis, BOD5, RPI

Hardwood stumpage price trends in New England

Treesearch

D.F. Dennis; P.E. Sendak

1991-01-01

Stumpage price trends in New Hampshire and Vermont varied considerably among species and products. Real stumpage price trends, expressed in 1988 dollars using the Producer Price Index to remove the effect of inflation, are reported for selected species and products. Long-term (1964-1989) trends in average annual prices are reported for New Hampshire and short-term (...

Daily and seasonal variability of pH, dissolved oxygen, temperature, and specific conductance in the Colorado River between the forebay of Glen Canyon, Dam and Lees Ferry, northeastern Arizona, 1998-99

USGS Publications Warehouse

Flynn, Marilyn E.; Hart, Robert J.; Marzolf, G. Richard; Bowser, Carl J.

2001-01-01

The productivity of the trout fishery in the tailwater reach of the Colorado River downstream from Glen Canyon Dam depends on the productivity of lower trophic levels. Photosynthesis and respiration are basic biological processes that control productivity and alter pH and oxygen concentration. During 1998?99, data were collected to aid in the documentation of short- and long-term trends in these basic ecosystem processes in the Glen Canyon reach. Dissolved-oxygen, temperature, and specific-conductance profile data were collected monthly in the forebay of Glen Canyon Dam to document the status of water chemistry in the reservoir. In addition, pH, dissolved-oxygen, temperature, and specific-conductance data were collected at five sites in the Colorado River tailwater of Glen Canyon Dam to document the daily, seasonal, and longitudinal range of variation in water chemistry that could occur annually within the Glen Canyon reach.

Time-variation of hydrothermal discharge at selected sites in the Western United States: Implications for monitoring

USGS Publications Warehouse

Ingebritsen, S.E.; Galloway, D.L.; Colvard, E.M.; Sorey, M.L.; Mariner, R.H.

2001-01-01

We compiled time series of hydrothermal discharge consisting of 3593 chloride- or heat-flux measurements from 24 sites in the Yellowstone region, the northern Oregon Cascades, Lassen Volcanic National Park and vicinity, and Long Valley, California. At all of these sites the hydrothermal phenomena are believed to be as yet unaffected by human activity, though much of the data collection was driven by mandates to collect environmental-baseline data in acticipation of geothermal development. The time series average 19 years in length and some of the Yellowstone sites have been monitored intermittently for over 30 years. Many sites show strong seasonality but few show clear long-term trends, and at most sites statistically significant decadal-scale trends are absent. Thus, the data provide robust estimates of advective heat flow ranging from ~130 MW in the north-central Oregon Cascades to ~6100 MW in the Yellowstone region, and also document Yellowstone hydrothermal chloride and arsenic fluxes of 1740 and 15-20 g/s, respectively. The discharge time series show little sensitivity to regional tectonic events such as earthquakes or inflation/deflation cycles. Most long-term monitoring to date has focused on high-chloride springs and low-temperature fumaroles. The relative stability of these features suggests that discharge measurements done as part of volcano-monitoring programs should focus instead on high-temperature fumaroles, which may be more immediately linked to the magmatic heat source. ?? 2001 Elsevier Science B.V. All rights reserved.

Newspaper Advertising Trends and Teacher Supply in the Carolinas.

ERIC Educational Resources Information Center

Dewalt, Mark W.; Graham, Patricia L.

This year-long research project documented critical issues of supply and demand for teachers in the Carolinas. Researchers focused on the number of public and private school education positions advertised in the four major newspapers serving South Carolina and the Charlotte metropolitan region of North Carolina. They documented advertising trends…

Long-term trends in DDT, PCBs, and chlordane in mussels from California

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

Stephenson, M.D.; Tjeerdema, R.S.

1994-12-31

Many contaminant programs have been established to study the geographical distributions and long-term trends of potential pollutants, but unfortunately, many have been short-lived because of economic cutbacks, providing limited information on long-term trends. The California State Mussel Watch program, however, has been continuously funded for the past 15 years. Several sites have been evaluated and were sampled often enough to obtain statistical resolution. Chlordane was evaluated at 29 stations, with 48% showing significant decreases over time; DDT was evaluated at 35 sites, with 43% showing significant declines; and PCBs were evaluated at 47 sites, with 21% showing significant drops overmore » time. Both DDT and PCBs showed declines, corresponding to decreases in their concentrations in the effluent, at sites located in the vicinity of the Los Angeles County municipal sewage outfall. This long-term investigation indicates that, contrary to public opinion, the banning of DDT, chlordane, and PCBs by the USEPA has led to overall improvement in water quality.« less

Analysis options for estimating status and trends in long-term monitoring

USGS Publications Warehouse

Bart, Jonathan; Beyer, Hawthorne L.

2012-01-01

This chapter describes methods for estimating long-term trends in ecological parameters. Other chapters in this volume discuss more advanced methods for analyzing monitoring data, but these methods may be relatively inaccessible to some readers. Therefore, this chapter provides an introduction to trend analysis for managers and biologists while also discussing general issues relevant to trend assessment in any long-term monitoring program. For simplicity, we focus on temporal trends in population size across years. We refer to the survey results for each year as the “annual means” (e.g. mean per transect, per plot, per time period). The methods apply with little or no modification, however, to formal estimates of population size, other temporal units (e.g. a month), to spatial or other dimensions such as elevation or a north–south gradient, and to other quantities such as chemical or geological parameters. The chapter primarily discusses methods for estimating population-wide parameters rather than studying variation in trend within the population, which can be examined using methods presented in other chapters (e.g. Chapters 7, 12, 20). We begin by reviewing key concepts related to trend analysis. We then describe how to evaluate potential bias in trend estimates. An overview of the statistical models used to quantify trends is then presented. We conclude by showing ways to estimate trends using simple methods that can be implemented with spreadsheets.

Prospective Trends in the Socio-Economic Context of Education in European Market Economy Countries.

ERIC Educational Resources Information Center

Weiss, M.; And Others

The purpose of this study was to project and analyze the prospective long-term trends in the socioeconomic context of the educational systems of European market economies and to outline in global terms the probable implication for education and training in the future. Composed of three chapters, the chapter 1 focuses on projected long-term…

Long-term trends in adolescent and young adult smoking in the United States: metapatterns and implications.

PubMed

Nelson, David E; Mowery, Paul; Asman, Kat; Pederson, Linda L; O'Malley, Patrick M; Malarcher, Ann; Maibach, Edward W; Pechacek, Terry F

2008-05-01

We sought to describe long-term adolescent and young adult smoking trends and patterns. We analyzed adolescent data from Monitoring the Future, 1976 to 2005, and young adult (aged 18-24 years) data from the National Health Interview Survey, 1974 to 2005, overall and in subpopulations to identify trends in current cigarette smoking prevalence. Five metapatterns emerged: we found (1) a large increase and subsequent decrease in overall smoking over the past 15 years, (2) a steep decline in smoking among Blacks through the early 1990s, (3) a gender gap reversal among older adolescents and young adults who smoked over the past 15 years, (4) similar trends in smoking for most subgroups since the early 1990s, and (5) a large decline in smoking among young adults with less than a high school education. Long-term patterns for adolescent and young adult cigarette smoking were decidedly nonlinear, and we found evidence of a cohort effect among young adults. Continued strong efforts and a long-term societal commitment to tobacco use prevention are needed, given the unprecedented declines in smoking among most subpopulations since the mid- to late 1990s.

High-Contrast Imaging of Intermediate-Mass Giants with Long-Term Radial Velocity Trends

NASA Technical Reports Server (NTRS)

Ryu, Tsuguru; Sato, Bun'ei; Kuzuhara, Masayuki; Narita, Norio; Takahashi, Yasuhiro; Uyama, Taichi; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun; Omiya, Masashi;

High-contrast Imaging of Intermediate-mass Giants with Long-term Radial Velocity Trends

NASA Astrophysics Data System (ADS)

Ryu, Tsuguru; Sato, Bun'ei; Kuzuhara, Masayuki; Narita, Norio; Takahashi, Yasuhiro H.; Uyama, Taichi; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun; Omiya, Masashi; Harakawa, Hiroki; Abe, Lyu; Ando, Hiroyasu; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph C.; Currie, Thayne; Egner, Sebastian; Feldt, Markus; Goto, Miwa; Grady, Carol A.; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko S.; Hełminiak, Krzysztof G.; Henning, Thomas; Hodapp, Klaus W.; Ida, Shigeru; Ishii, Miki; Itoh, Yoichi; Iye, Masanori; Izumiura, Hideyuki; Janson, Markus; Kambe, Eiji; Kandori, Ryo; Knapp, Gillian R.; Kokubo, Eiichiro; Kwon, Jungmi; Matsuo, Taro; Mayama, Satoshi; McElwain, Michael W.; Mede, Kyle; Miyama, Shoken; Morino, Jun-Ichi; Moro-Martin, Amaya; Nishimura, Tetsuo; Pyo, Tae-Soo; Serabyn, Eugene; Suenaga, Takuya; Suto, Hiroshi; Suzuki, Ryuji; Takami, Michihiro; Takato, Naruhisa; Takeda, Yoichi; Terada, Hiroshi; Thalmann, Christian; Turner, Edwin L.; Watanabe, Makoto; Wisniewski, John; Yamada, Toru; Yoshida, Michitoshi; Takami, Hideki; Usuda, Tomonori; Tamura, Motohide

2016-07-01

A radial velocity (RV) survey for intermediate-mass giants has been in operation for over a decade at Okayama Astrophysical Observatory (OAO). The OAO survey has revealed that some giants show long-term linear RV accelerations (RV trends), indicating the presence of outer companions. Direct-imaging observations can help clarify what objects generate these RV trends. We present the results of high-contrast imaging observations of six intermediate-mass giants with long-term RV trends using the Subaru Telescope and HiCIAO camera. We detected co-moving companions to γ Hya B ({0.61}-0.14+0.12{M}⊙ ), HD 5608 B (0.10+/- 0.01{M}⊙ ), and HD 109272 B (0.28+/- 0.06{M}⊙ ). For the remaining targets (ι Dra, 18 Del, and HD 14067), we exclude companions more massive than 30-60 M Jup at projected separations of 1″-7″. We examine whether these directly imaged companions or unidentified long-period companions can account for the RV trends observed around the six giants. We find that the Kozai mechanism can explain the high eccentricity of the inner planets ι Dra b, HD 5608 b, and HD 14067 b.

A Case Study: The Potential of Energy Efficiency in Senior High School of Semarang Regency, Central Java, Indonesia

NASA Astrophysics Data System (ADS)

Yustika, Ana; Purwanto; Hermawan, H.

2018-02-01

The increasing of energy supply trend in Indonesia seems to be a serious problem in the implementation of sustainable development. This study case research aimed to determine the potential of energy efficiency in school environment. The subject of this research was SMA N 1 Ambarawa, located on Semarang Regency of Central Java, Indonesia. The data collection was done by used documentation, observation and interview method. The results showed that the average of electrical energy consumption in this school reached 11022.008 kWh/month, which resulted in the emergence of secondary emissions of CO2 by 9644.257 kg CO2/month. Overall, the consumption of electrical energy in this school was very efficient, with an Intensity of Energy Consumption (IEC) average 1.7957 kWh/m2/month. In this case, the implementation of short-term no cost, long-term no cost, middle-cost, short-term high cost and long-term high-cost recommendation could save electricity energy sequent by 3.159%; 7.536%; 9.499%; 35.278% - 36.626%; and 42.084%. In conclusion, the school environment had a big potential of energy efficiency that could reduce the energy consumption and CO2 gas emissions.

Ionospheric Trend Over Wuhan During 1947-2017: Comparison Between Simulation and Observation

NASA Astrophysics Data System (ADS)

Yue, Xinan; Hu, Lianhuan; Wei, Yong; Wan, Weixing; Ning, Baiqi

2018-02-01

Since Roble and Dickinson (1989), who drew the community's attention about the greenhouse gas effect on the ionosphere, huge efforts have been implemented on ionospheric climate study. However, direct comparison between observations and simulations is still rare. Recently, the Wuhan ionosonde observations were digitized and standardized through unified method back to 1947. In this study, the NCAR-TIEGCM was driven by Mauna Loa Observatory observed CO2 level and International Geomagnetic Reference Field (IGRF) geomagnetic field to simulate their effects on ionospheric long-term trend over Wuhan. Only March equinox was considered in both data analysis and simulation. Simulation results show that the CO2 and geomagnetic field have comparable effect on hmF2 trend, while geomagnetic field effect is stronger than CO2 on foF2 trend over Wuhan. Both factors result in obvious but different diurnal variations of foF2/hmF2 long-term trends. The geomagnetic field effect is nonlinear versus years since the long-term variation of geomagnetic field intensity and orientation is complex. Mean value of foF2 and hmF2 trend is (-0.0021 MHz/yr, -0.106 km/yr) and (-0.0022 MHz/yr, -0.0763 km/yr) for observation and simulation, respectively. Regarding the diurnal variation of the trend, the simulation accords well with that of observation except hmF2 results around 12 UT. Overall, good agreement between observation and simulation illustrates the good quality of Wuhan ionosonde long-term data and the validity of ancient ionosphere reconstruction based on realistic indices driving simulation.

Preface to Long-term trends in the upper atmosphere and ionosphere

NASA Astrophysics Data System (ADS)

Laštovička, J.; Lübken, F.-J.

2017-10-01

The anthropogenic emissions of greenhouse gases influence the atmosphere at nearly all altitudes between the ground and the topside ionosphere and upper thermosphere, thus affecting not only life on the surface, but also the space-based technological systems on which we increasingly rely. This special issue deals with long-term trends in the mesosphere, thermosphere, ionosphere, and partly also in the stratosphere, which are predominantly (but not only) caused by anthropogenic factors, particularly by the increasing concentration of carbon dioxide in the atmosphere. The special issue is based on selected papers from the 9th IAGA/ICMA/SCOSTEP workshop ;Long-Term Changes and Trends in the Atmosphere; held in September 2016 in Kühlungsborn, Germany. The 10th workshop will be held in June 2018 in Hefei, China.

Late holocene climate changes in eastern North America estimated from pollen data

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

Gajewski, K.

Well-dated pollen profiles from six sites from Maine to Minnesota record vegetation changes indicative of summer temperature and annual precipitation variations over the past 2000 yr. Laminations in the sediment provide accurate time control. Multiple regression techniques were used to calculate calibration functions from a spatial network of modern pollen and climate data. When applied to the six pollen diagrams, these calibration functions yielded estimates that show a long-term trend toward lower summer temperature. Superimposed on this long-term trend are short-term fluctuations that are frequently in phase at the sites. Departures from the long-term cooling trend are positive around 1500more » yr ago (indicating relative warmth) and negative between 200 and 500 yr ago (indicating relative cold). Annual precipitation showed a slight increase at several sites during the past 1000 yr relative to the previous 1000 yr.« less

Banking: financing trends in an acquisitive health care market--focus on long-term care.

PubMed

Gordon, L J; Bressler, A

1998-01-01

This article reviews the long-term care sector of the health care industry, particularly the factors driving sector consolidation and, through the use of four transactions as a platform, discusses key credit issues and risks facing long-term care companies.

Guidance for implementing the long-term surveillance program for UMTRA Project Title I Disposal Sites

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

NONE

1996-02-01

This guidance document has two purposes: it provides guidance for writing site-specific long-term surveillance plans (LTSP) and it describes site surveillance, monitoring, and long-term care techniques for Title I disposal sites of the Uranium Mill Tailings Radiation Control Act (UMTRCA) (42 USC Section 7901 et seq.). Long-term care includes monitoring, maintenance, and emergency measures needed to protect public health and safety and the environment after remedial action is completed. This document applies to the UMTRCA-designated Title I disposal sites. The requirements for long-term care of the Title I sites and the contents of the LTSPs are provided in U.S. Nuclearmore » Regulatory Commission (NRC) regulations (10 CFR Section 40.27) provided in Attachment 1.« less

Can data from disparate long-term fish monitoring programs be used to increase our understanding of regional and continental trends in large river assemblages?

USGS Publications Warehouse

Counihan, Timothy D.; Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.

2018-01-01

Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers.

Can data from disparate long-term fish monitoring programs be used to increase our understanding of regional and continental trends in large river assemblages?

PubMed Central

Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian S.; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.

2018-01-01

Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers. PMID:29364953

NASA standard: Trend analysis techniques

NASA Technical Reports Server (NTRS)

1990-01-01

Descriptive and analytical techniques for NASA trend analysis applications are presented in this standard. Trend analysis is applicable in all organizational elements of NASA connected with, or supporting, developmental/operational programs. This document should be consulted for any data analysis activity requiring the identification or interpretation of trends. Trend analysis is neither a precise term nor a circumscribed methodology: it generally connotes quantitative analysis of time-series data. For NASA activities, the appropriate and applicable techniques include descriptive and graphical statistics, and the fitting or modeling of data by linear, quadratic, and exponential models. Usually, but not always, the data is time-series in nature. Concepts such as autocorrelation and techniques such as Box-Jenkins time-series analysis would only rarely apply and are not included in this document. The basic ideas needed for qualitative and quantitative assessment of trends along with relevant examples are presented.

Energy resources - cornucopia or empty barrel?

USGS Publications Warehouse

McCabe, P.J.

1998-01-01

Over the last 25 yr, considerable debate has continued about the future supply of fossil fuel. On one side are those who believe we are rapidly depleting resources and that the resulting shortages will have a profound impact on society. On the other side are those who see no impending crisis because long-term trends are for cheaper prices despite rising production. The concepts of resources and reserves have historically created considerable misunderstanding in the minds of many nongeologists. Hubbert-type predictions of energy production assume that there is a finite supply of energy that is measurable; however, estimates of resources and reserves are inventories of the amounts of a fossil fuel perceived to be available over some future period of time. As those resources/reserves are depleted over time, additional amounts of fossil fuels are inventoried. Throughout most of this century, for example, crude oil reserves in the United States have represented a 10-14-yr supply. For the last 50 yr, resource crude oil estimates have represented about a 60-70-yr supply for the United States. Division of reserve or resource estimates by current or projected annual consumption therefore is circular in reasoning and can lead to highly erroneous conclusions. Production histories of fossil fuels are driven more by demand than by the geologic abundance of the resource. Examination of some energy resources with well-documented histories leads to two conceptual models that relate production to price. The closed-market model assumes that there is only one source of energy available. Although the price initially may fall because of economies of scale long term, prices rise as the energy source is depleted and it becomes progressively more expensive to extract. By contrast, the open-market model assumes that there is a variety of available energy sources and that competition among them leads to long-term stable or falling prices. At the moment, the United States and the world approximate the open-market model, but in the long run the supply of fossil fuel is finite, and prices inevitably will rise unless alternate energy sources substitute for fossil energy supplies; however, there appears little reason to suspect that long-term price trends will rise significantly over the next few decades.Over the last 25 years, considerable debate has continued about the future supply of fossil fuel. On one side are those who believe that resources are rapidly depleting and that the resulting shortages will have a profound impact on society. On the other side are those who see no impending crisis because longterm trends are for cheaper prices despite rising production. This paper examines historic trends and clarify the foundations on which one may build one's predictions.

Vertical structure of stratospheric water vapour trends derived from merged satellite data

PubMed Central

Hegglin, M. I.; Plummer, D. A.; Shepherd, T. G.; Scinocca, J. F.; Anderson, J.; Froidevaux, L.; Funke, B.; Hurst, D.; Rozanov, A.; Urban, J.; von Clarmann, T.; Walker, K. A.; Wang, H. J.; Tegtmeier, S.; Weigel, K.

2017-01-01

Stratospheric water vapour is a powerful greenhouse gas. The longest available record from balloon observations over Boulder, Colorado, USA shows increases in stratospheric water vapour concentrations that cannot be fully explained by observed changes in the main drivers, tropical tropopause temperatures and methane. Satellite observations could help resolve the issue, but constructing a reliable long-term data record from individual short satellite records is challenging. Here we present an approach to merge satellite data sets with the help of a chemistry-climate model nudged to observed meteorology. We use the models' water vapour as a transfer function between data sets that overcomes issues arising from instrument drift and short overlap periods. In the lower stratosphere, our water vapour record extends back to 1988 and water vapour concentrations largely follow tropical tropopause temperatures. Lower and mid-stratospheric long-term trends are negative, and the trends from Boulder are shown not to be globally representative. In the upper stratosphere, our record extends back to 1986 and shows positive long-term trends. The altitudinal differences in the trends are explained by methane oxidation together with a strengthened lower-stratospheric and a weakened upper-stratospheric circulation inferred by this analysis. Our results call into question previous estimates of surface radiative forcing based on presumed global long-term increases in water vapour concentrations in the lower stratosphere. PMID:29263751

Long Term Trend Analysis and Assessment of Water Quality in the Penchala River, Malaysia

NASA Astrophysics Data System (ADS)

Chow, M. F.; Haris, H. B.; Mohd Sidek, L. B.

2014-12-01

Rapid urban expansion produces negative impacts on the natural environment, especially river water quality. Studies assessing long term changes of water quality have been recognized as a key tool for understanding ongoing processes in watersheds and for providing an essential background for evaluation of rapid changes within industrialized and populated urban areas. Unfortunately, only limited studies are available for developing countries such as Malaysia. Thus, a long term study was conducted to evaluate water quality trends at Pencala river basin that has undergone extensive land use changes related to industrial, agricultural and urban activities. Fifteen physical and chemical variables were analysed in river water samples collected every month over a period of 13 years, between 1997 and 2009. The trend study was performed using the Mann-Kendall Seasonal test and the Sen's Slope estimator. Results revealed that most water quality parameters showed a downward trend for yearly average concentration. The water quality index (WQI) for Pencala River was improved from Class V to Class IV, according to National Water Quality Standards for Malaysia. BOD, COD, NH3-N and SS show trends toward decreasing concentrations over time. The improvements seen in water quality appear to be the result of improved wastewater treatment and other water quality improvement efforts achieved through government initiative. Continued long-term and high frequency monitoring is necessary to establish plans and policies for effective water resources management.

Vertical structure of stratospheric water vapour trends derived from merged satellite data.

PubMed

Hegglin, M I; Plummer, D A; Shepherd, T G; Scinocca, J F; Anderson, J; Froidevaux, L; Funke, B; Hurst, D; Rozanov, A; Urban, J; von Clarmann, T; Walker, K A; Wang, H J; Tegtmeier, S; Weigel, K

2014-01-01

Stratospheric water vapour is a powerful greenhouse gas. The longest available record from balloon observations over Boulder, Colorado, USA shows increases in stratospheric water vapour concentrations that cannot be fully explained by observed changes in the main drivers, tropical tropopause temperatures and methane. Satellite observations could help resolve the issue, but constructing a reliable long-term data record from individual short satellite records is challenging. Here we present an approach to merge satellite data sets with the help of a chemistry-climate model nudged to observed meteorology. We use the models' water vapour as a transfer function between data sets that overcomes issues arising from instrument drift and short overlap periods. In the lower stratosphere, our water vapour record extends back to 1988 and water vapour concentrations largely follow tropical tropopause temperatures. Lower and mid-stratospheric long-term trends are negative, and the trends from Boulder are shown not to be globally representative. In the upper stratosphere, our record extends back to 1986 and shows positive long-term trends. The altitudinal differences in the trends are explained by methane oxidation together with a strengthened lower-stratospheric and a weakened upper-stratospheric circulation inferred by this analysis. Our results call into question previous estimates of surface radiative forcing based on presumed global long-term increases in water vapour concentrations in the lower stratosphere.

Evolutionary model of stock markets

NASA Astrophysics Data System (ADS)

Kaldasch, Joachim

2014-12-01

The paper presents an evolutionary economic model for the price evolution of stocks. Treating a stock market as a self-organized system governed by a fast purchase process and slow variations of demand and supply the model suggests that the short term price distribution has the form a logistic (Laplace) distribution. The long term return can be described by Laplace-Gaussian mixture distributions. The long term mean price evolution is governed by a Walrus equation, which can be transformed into a replicator equation. This allows quantifying the evolutionary price competition between stocks. The theory suggests that stock prices scaled by the price over all stocks can be used to investigate long-term trends in a Fisher-Pry plot. The price competition that follows from the model is illustrated by examining the empirical long-term price trends of two stocks.

Preserving Long-Term Access to United States Government Documents in Legacy Digital Formats

ERIC Educational Resources Information Center

Woods, Kam A.

2010-01-01

Over the past several decades, millions of digital objects of significant scientific, economic, cultural, and historic value have been published and distributed to libraries and archives on removable media. Providing long-term access to these documents, media files, and software executables is an increasingly complex task because of dependencies…

Long-term trend of foE in European higher middle latitudes

NASA Astrophysics Data System (ADS)

Laštovička, Jan

2016-04-01

Long-term changes and trends have been observed in the whole ionosphere below its maximum. As concerns the E region, historical global data (Bremer, 2008) provide predominantly slightly positive trend, even though some stations provide a negative trend. Here we use data of two European stations with the best long data series of parameters of the ionospheric E layer, Slough/Chilton and Juliusruh over 1975-2014 (40 years). Noon-time medians (10-14 LT) are analyzed. The trend pattern after removing solar influence is complex. For yearly average values for Chilton first foE is decreasing in 1975-1990 by about 0.1 MHz, then the trend levels off or a little increase occurs in 1990-2004, and finally in 2004-2014 again a decrease is observed (again by about 0.1 MHz but over shorter period). Juliusruh yields a similar pattern. Similar analysis is also done for some months to check seasonal dependence of trends. The stability of relation between solar activity and foE is tested to clarify potential role of this factor in apparent trend of foE.

Using nestling plasma to assess long-term spatial and temporal concentrations of organochlorine compounds in bald eagles within Voyageurs National Park, Minnesota, USA

Treesearch

H. Tyler Pittman; William W. Bowerman; Leland H. Grim; Teryl G. Grubb; William C. Bridges; Michael R. Wierda

2015-01-01

The bald eagle (Haliaeetus leucocephalus) population at Voyageurs National Park (VNP) provides an opportunity to assess long-term temporal and spatial trends of persistent environmental contaminants. Nestling bald eagle plasma samples collected from 1997 to 2010 were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides. Trends of total PCBs,...

Long-term streamflow trends on California’s north coast

Treesearch

J. Eli Asarian; Jeffrey D. Walker

2017-01-01

Using streamflow data from the U.S. Geological Survey, we assessed long-term (1953-2012) trends in streamflow on California’s North Coast including many sites in the redwood region. The study area spans from the Smith River to the Mattole River and includes the Eel and Klamath-Trinity basins. Antecedent Precipitation Index (API) is a time-weighted summary of...

The long term agroecosystem research network - shared research strategy

Treesearch

Jean L. Steiner; Timothy Strickland; Peter J.A. Kleinman; Kris Havstad; Thomas B. Moorman; M.Susan Moran; Phil Hellman; Ray B. Bryant; David Huggins; Greg McCarty

2016-01-01

While current weather patterns and rapidly accelerated changes in technology often focus attention on short-term trends in agriculture, the fundamental demands on modern agriculture to meet society food, feed, fuel and fiber production while providing the foundation for a healthy environment requires long-term perspective. The Long- Term Agroecoystem Research Network...

Correction of stream quality trends for the effects of laboratory measurement bias

USGS Publications Warehouse

Alexander, Richard B.; Smith, Richard A.; Schwarz, Gregory E.

1993-01-01

We present a statistical model relating measurements of water quality to associated errors in laboratory methods. Estimation of the model allows us to correct trends in water quality for long-term and short-term variations in laboratory measurement errors. An illustration of the bias correction method for a large national set of stream water quality and quality assurance data shows that reductions in the bias of estimates of water quality trend slopes are achieved at the expense of increases in the variance of these estimates. Slight improvements occur in the precision of estimates of trend in bias by using correlative information on bias and water quality to estimate random variations in measurement bias. The results of this investigation stress the need for reliable, long-term quality assurance data and efficient statistical methods to assess the effects of measurement errors on the detection of water quality trends.

Thirty Years of Cloud Cover Patterns from Satellite Data: Fog in California's Central Valley and Coast

NASA Astrophysics Data System (ADS)

Waller, E.; Baldocchi, D. D.

2012-12-01

In an effort to assess long term trends in winter fog in the Central Valley of California, custom maps of daily cloud cover from an approximately 30 year record of AVHRR (1981-1999) and MODIS (2000-2012) satellite data were generated. Spatial rules were then used to differentiate between fog and general cloud cover. Differences among the sensors (e.g., spectral content, spatial resolution, overpass time) presented problems of consistency, but concurrent climate station data were used to resolve systematic differences in products, and to confirm long term trends. The frequency and extent of Central Valley ("Tule") fog appear to have some periodic oscillation, but also appear to be on the decline, especially in the Sacramento Valley and in the "shoulder" months of November and February. These results may have strong implications for growers of fruit and nut trees in the Central Valley dependent on winter chill hours that are augmented by the foggy daytime conditions. Conclusions about long term trends in fog are limited to daytime patterns, as results are primarily derived from reflectance-based products. Similar analyses of daytime cloud cover are performed on other areas of concern, such as the coastal fog belt of California. Large area and long term patterns here appear to have periodic oscillation similar to that for the Central Valley. However, the relatively coarse spatial resolution of the AVHRR LTDR (Long Term Data Record) data (~5-km) may be limiting for fine-scale analysis of trends.

Documenting the use of the Long Term Resource Monitoring element’s fish monitoring methodologies throughout the Midwest

USGS Publications Warehouse

Solomon, Levi E.; Casper, Andrew F.

2016-08-16

The Upper Mississippi River Restoration (UMRR) Program’s Long Term Resource Monitoring (LTRM) element is designed to monitor and assess long term trends in the Upper Mississippi River System (UMRS). To accomplish this, standardized methods are used that allow for comparisons across pools and rivers. In recent years, other projects and other agencies have adopted the LTRM fish methodologies for use outside the UMRR. To determine how widespread the use of the Fish Component’s methods are, a twelve question survey was delivered via SurveyMonkey.com through the states comprising the American Fisheries Society (AFS) North Central Division and the Upper Mississippi River Conservation Committee. Approximately 2,000 professionals were reached with ≈11 percent participating. Results indicate that nearly all (95 percent) respondents use standardized methods in their sampling and 48 percent are familiar with the LTRM fish methodologies. Roughly one-third (35 percent) of all respondents have used the methods in the past and most (78 percent) of those have modified the methods to suit the information needs specific to their fishery. Results indicate that the LTRM methods have indeed spread outside the UMRR and are now a well-known and potentially widely used technique to sample fish communities.

46 CFR 356.43 - Long-term or exclusive sales contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the vessel or the vessel's operation, management and harvesting activities. (b) Provisions of a long... control over the operation, management or harvesting activities of the vessel, vessel owner, or bareboat... DOCUMENTATION Charters, Management Agreements and Exclusive or Long-Term Contracts § 356.43 Long-term or...

Pneumonia Mortality in Children Aged <5 Years in 56 Countries: A Retrospective Analysis of Trends from 1960 to 2012.

PubMed

Wu, Jie; Yang, Shigui; Cao, Qing; Ding, Cheng; Cui, Yuanxia; Zhou, Yuqing; Li, Yiping; Deng, Min; Wang, Chencheng; Xu, Kaijin; Ruan, Bing; Li, Lanjuan

2017-10-30

Pneumonia is now the second leading cause of death for children aged <5 years worldwide. However, analyses of the long-term evolution of under-5 mortality from pneumonia are still scarce in the literature. We aimed to explore long-term trends of under-5 mortality from pneumonia in 56 countries from 1960 to 2012. Data on under-5 mortality from pneumonia were extracted from the World Health Organization mortality database. Long-term trends were assessed for 56 countries and for 4 national income transition groups. We also used joinpoint regression analysis to detect distinct period segments of long-term trends and estimate the annual percent of changes of each period segment. The average mortality rate from pneumonia for children aged 0-4 years in 56 countries declined from 163.0 per 100000 children (95% confidence interval [CI], 119.4 to 212.8) in 1960 to 9.9 per 100000 children (95% CI, 6.4 to 13.4) in 2012, with an average annual percent of change of -5.6% (95% CI, -7.2% to -3.9%). The temporal trends of childhood mortality were different between national income transition groups. Our findings suggest a striking overall downward trend in under-5 mortality from pneumonia between 1960 and 2012. However, the rate and absolute terms of decline differ by national income transition group. These variable patterns between national income transition groups may inform further intervention setting and priority setting. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Processing short-term and long-term information with a combination of polynomial approximation techniques and time-delay neural networks.

PubMed

Fuchs, Erich; Gruber, Christian; Reitmaier, Tobias; Sick, Bernhard

2009-09-01

Neural networks are often used to process temporal information, i.e., any kind of information related to time series. In many cases, time series contain short-term and long-term trends or behavior. This paper presents a new approach to capture temporal information with various reference periods simultaneously. A least squares approximation of the time series with orthogonal polynomials will be used to describe short-term trends contained in a signal (average, increase, curvature, etc.). Long-term behavior will be modeled with the tapped delay lines of a time-delay neural network (TDNN). This network takes the coefficients of the orthogonal expansion of the approximating polynomial as inputs such considering short-term and long-term information efficiently. The advantages of the method will be demonstrated by means of artificial data and two real-world application examples, the prediction of the user number in a computer network and online tool wear classification in turning.

Disaster risk assessment case study: Recent drought on the Navajo Nation, USA

USGS Publications Warehouse

Hiza, Margaret; Kelley, Klara B.; Francis, Harris; Block, Debra

2011-01-01

The Navajo Nation is an ecologically sensitive semi-arid to arid section of the southern Colorado Plateau. In this remote part of the United States, located at the Four Corners (Arizona, New Mexico, Colorado, and Utah), traditional people live a subsistence lifestyle that is inextricably tied to, and dependent upon, landscape conditions and water supplies. Soft bedrock lithologies and sand dunes dominate the region, making it highly sensitive to fluctuations in precipitation intensity, percent vegetation cover, and local land use practices. However, this region has sparse and discontinuous meteorological monitoring records. As a complement to the scant long-term meteorological records and historical documentation, we conducted interviews with 50 Native American elders from the Navajo Nation and compiled their lifetime observations on the changes in water availability, weather, and sand or dust storms. We then used these observations to further refine our understanding of the historical trends and impacts of climate change and drought for the region. In addition to altered landscape conditions due to climatic change, drought, and varying land use practices over the last 130 years, the Navajo people have been affected by federal policies and harsh economic conditions which weaken their cultural fabric. We conclude that a long-term drying trend and decreasing snowpack, superimposed on regional drought cycles, will magnify drought impacts on the Navajo Nation and leave its people increasingly vulnerable.

Long-term interactions between migratory caribou, wildfires and Nunavik hunters inferred from tree rings.

PubMed

Payette, Serge; Boudreau, Stéphane; Morneau, Claude; Pitre, Nadia

2004-12-01

Barren-ground caribou (Rangifer tarandus) herds in North America may reach considerable size and undertake large-scale seasonal migrations from the Arctic tundra to the boreal forest. To test the caribou decline hypothesis associated with native harvesting and fire, we have documented the long-term trends of caribou activity based on a novel approach which uses tree-ring dated trampling scars produced by caribou hooves in the extensive trails distributed over the summer and winter ranges of the Rivièreaux-Feuilles herd (RAF herd, east of Hudson Bay in northern Quebec). The age structure data of trampling scars from lichen woodlands distributed over the entire RAF range confirmed the overall trends of caribou activity from the late 1700s to present time. Over the last 200 years, the RAF herd has undergone two highs in the late 1700s and 1900s separated by a moderate activity pattern in the late 1800s. Native harvesting was possibly involved in the early 1900s decline, although at a moderate level. The reduced magnitude of caribou activity during this period has not modified the natural cycle of highs and lows, which suggests that other demographic factors were controlling the changing caribou abundance. Our data also show that only exceptionally large fires may have a minor, short-lived impact on caribou migrations but not on caribou numbers.

Assessment of indexing trends with specific and general terms for herbal medicine.

PubMed

Bartol, Tomaz

2012-12-01

Concepts for medicinal plants are represented by a variety of associated general terms with specific indexing patterns in databases, which may not consistently reflect growth of records. The objectives of this study are to assess the development in databases by identifying general terms that describe herbal medicine with optimal retrieval recall and to identify possible special trends in co-occurrence of specific and general concepts. Different search strategies are tested in cab abstracts, medline and web of science. Specific terms (Origanum and Salvia) are employed. Relevant general terms (e.g. 'Plants, Medicinal', Phytotherapy, Herbal drugs) are identified, along with indexing trends and co-occurrences. Growth trends, in specific (narrower) terms, are similar among databases. General terms, however, exhibit dissimilar trends, sometimes almost opposing one another. Co-occurrence of specific and general terms is changing over time. General terms may not denote definite development of trends as the use of terms differs amongst databases, making it difficult to correctly assess possible numbers of relevant records. Perceived increase can, sometimes, be attributed to an increased occurrence of a more general term alongside the specific one. Thesaurus-controlled databases may yield more hits, because of 'up-posted' (broader) terms. Use of broader terms is helpful as it enhances retrieval of relevant documents. © 2012 The authors. Health Information and Libraries Journal © 2012 Health Libraries Group.

Trends in significant wave height and surface wind speed in the China Seas between 1988 and 2011

NASA Astrophysics Data System (ADS)

Zheng, Chongwei; Zhang, Ren; Shi, Weilai; Li, Xin; Chen, Xuan

2017-10-01

Wind and waves are key components of the climate system as they drive air-sea interactions and influence weather systems and atmospheric circulation. In marine environments, understanding surface wind and wave fields and their evolution over time is important for conducting safe and efficient human activities, such as navigation and engineering. This study considers long-term trends in the sea surface wind speed (WS) and significant wave height (SWH) in the China Seas over the period 1988-2011 using the Cross-Calibrated Multi-Platform (CCMP) ocean surface wind product and a 24-year hindcast wave dataset obtained from the WAVEWATCH-III (WW3) wave model forced with CCMP winds. The long-term trends in WS and SWH in the China Seas are analyzed over the past 24 years to provide a reference point from which to assess future climate change and offshore wind and wave energy resource development in the region. Results demonstrate that over the period 1988-2011 in the China Seas: 1) WS and SWH showed a significant increasing trend of 3.38 cm s-1 yr-1 and 1.52 cm yr-1, respectively; 2) there were notable regional differences in the long-term trends of WS and SWH; 3) areas with strong increasing trends were located mainly in the middle of the Tsushima Strait, the northern and southern areas of the Taiwan Strait, and in nearshore regions of the northern South China Sea; and 4) the long-term trend in WS was closely associated with El Niño and a significant increase in the occurrence of gale force winds in the region.

Alzheimer's Disease, Long-Term Care, and Health Policy: Who's Going To Pay the Bill?

ERIC Educational Resources Information Center

Monath, Jennifer

1997-01-01

Discusses the disparity in research funding for Alzheimer's Disease (AD), the future of health-care policy and the need for reform. Provides an annotated bibliography of sources related to AD, long-term care, and health policy. The types of documents covered include journals, government documents, and grey literature (material not readily…

Development of the Long-Term Agro-ecosystem Research (LTAR) Network: Current status and future trends

USDA-ARS?s Scientific Manuscript database

Long-term research conducted at multiple scales is critical to assessing the effects of key long term drivers (e.g., global population growth; land-use change; increased competition for natural resources; climate variability and change) on our ability to sustain or enhance agricultural production to...

Labor Trends: Overview of the United States, New York City, and Long Island. Revised Edition.

ERIC Educational Resources Information Center

Goldstein, Cheryl

This document summarizes employment statistics and trends, with a geographic emphasis on areas where Queensborough Community College (New York) students and graduates seek employment. Data are presented on the following: (1) current and projected United States labor force; (2) occupational outlook; (3) employment status of civilian labor force 25…

Is solar correction for long-term trend studies stable?

NASA Astrophysics Data System (ADS)

Laštovička, Jan

2017-04-01

When calculating long-term trends in the ionosphere, the effect of the 11-year solar cycle (i.e. of solar activity) must be removed from data, because it is much stronger than the long-term trend. When a data series is analyzed for trend, usual approach is first to calculate from all data their dependence on solar activity and create an observational model of dependence on solar activity. Then the model data are subtracted from observations and trend is computed from residuals. This means that it is assumed that the solar activity dependence is stable over the whole data series period of time. But what happens if it is not the case? As an ionospheric parameter we consider foE from two European stations with the best long data series of parameters of the ionospheric E layer, Slough/Chilton and Juliusruh over 1975-2014 (40 years). Noon-time medians (10-14 LT) are analyzed. The trend pattern after removing solar influence with one correction for the whole period is complex. For yearly average values for both stations first foE is slightly decreasing in 1975-1990, then the trend levels off or a very little increase occurs in 1990-2005, and finally in 2006-2014 a remarkable decrease is observed. This does not seem to be physically plausible. However, when the solar correction is calculated separately for the three above periods, we obtain a smooth slightly negative trend which changes after the mid-1990 into no trend in coincidence with change of ozone trend. While solar corrections for the first two periods are similar (even though not equal), the solar activity dependence of foE in the third period (lower solar activity) is clearly different. Also foF2 trend revealed some effect of unstable solar correction. Thus the stability of solar correction should be carefully tested when calculating ionospheric trends. This could perhaps explain some of differences between the past published trend results.

Top-down and bottom-up factors affecting seabird population trends in the California current system (1985-2006)

NASA Astrophysics Data System (ADS)

Ainley, David G.; David Hyrenbach, K.

2010-03-01

To characterize the environmental factors affecting seabird population trends in the central portion of the California current system (CCS), we analyzed standardized vessel-based surveys collected during the late spring (May-June) upwelling season over 22 yr (1985-2006). We tested the working hypothesis that population trends are related to species-specific foraging ecology, and predicted that temporal variation in population size should be most extreme in diving species with higher energy expenditure during foraging. We related variation in individual species abundance (number km -2) to seasonally lagged (late winter, early spring, late spring) and concurrent ocean conditions, and to long-term trends (using a proxy variable: year) during a multi-decadal period of major fluctuations in the El Niño-Southern oscillation (ENSO) and the Pacific decadal oscillation (PDO). We considered both remote (Multivariate ENSO Index, PDO) and local (coastal upwelling indices and sea-surface temperature) environmental variables as proxies for ocean productivity and prey availability. We also related seabird trends to those of potentially major trophic competitors, humpback ( Megaptera novaeangliae) and blue ( Balaenoptera musculus) whales, which increased in number 4-5-fold midway during our study. Cyclical oscillations in seabird abundance were apparent in the black-footed albatross ( Phoebastria nigripes), and decreasing trends were documented for ashy storm-petrel ( Oceanodroma homochroa), pigeon guillemot ( Cepphus columbus), rhinoceros auklet ( Cerorhinca monocerata), Cassin’s auklet ( Ptychoramphus aleuticus), and western gull ( Larus occidentalis); the sooty shearwater ( Puffinus griseus), exhibited a marked decline before signs of recovery at the end of the study period. The abundance of nine other focal species varied with ocean conditions, but without decadal or long-term trends. Six of these species have the largest global populations in the CCS, and four are highly energetic, diving foragers. Furthermore, three of the diving species trends were negatively correlated with the abundance of humpback whales in the study area, a direct competitor for the same prey. Therefore, on the basis of literature reviewed, we hypothesize that the seabirds were affected by the decreasing carrying capacity of the CCS, over-exploitation of some prey stocks and interference competition from the previously exploited, but now increasing, baleen whale populations. Overall, our study highlights the complexity of the ecological factors driving seabird population trends in the highly variable and rapidly changing CCS ecosystem.

Rating curve estimation of nutrient loads in Iowa rivers

USGS Publications Warehouse

Stenback, G.A.; Crumpton, W.G.; Schilling, K.E.; Helmers, M.J.

2011-01-01

Accurate estimation of nutrient loads in rivers and streams is critical for many applications including determination of sources of nutrient loads in watersheds, evaluating long-term trends in loads, and estimating loading to downstream waterbodies. Since in many cases nutrient concentrations are measured on a weekly or monthly frequency, there is a need to estimate concentration and loads during periods when no data is available. The objectives of this study were to: (i) document the performance of a multiple regression model to predict loads of nitrate and total phosphorus (TP) in Iowa rivers and streams; (ii) determine whether there is any systematic bias in the load prediction estimates for nitrate and TP; and (iii) evaluate streamflow and concentration factors that could affect the load prediction efficiency. A commonly cited rating curve regression is utilized to estimate riverine nitrate and TP loads for rivers in Iowa with watershed areas ranging from 17.4 to over 34,600km2. Forty-nine nitrate and 44 TP datasets each comprising 5-22years of approximately weekly to monthly concentrations were examined. Three nitrate data sets had sample collection frequencies averaging about three samples per week. The accuracy and precision of annual and long term riverine load prediction was assessed by direct comparison of rating curve load predictions with observed daily loads. Significant positive bias of annual and long term nitrate loads was detected. Long term rating curve nitrate load predictions exceeded observed loads by 25% or more at 33% of the 49 measurement sites. No bias was found for TP load prediction although 15% of the 44 cases either underestimated or overestimate observed long-term loads by more than 25%. The rating curve was found to poorly characterize nitrate and phosphorus variation in some rivers. ?? 2010 .

Secular changes of the M2 tide in the Gulf of Maine

NASA Technical Reports Server (NTRS)

Ray, Richard D.

2005-01-01

Analyses of long time series of hourly tide-gauge data at four stations in the Gulf of Maine reveal that the amplitude of the M2 tide underwent a nearly linear secular increase throughout most of the twentieth century. In the early 1980s, however, the amplitude of M2 abruptly dropped. Sea level changes alone appear inadequate to explain either the long-term trend or the recent trend discontinuity. Tidal models that account for Holocene sea level rise do predict an amplification of M2, but much smaller than the currently observed trends. Nor do recent annual mean sea levels correlate with the recent trend discontinuity. Some unknown fraction of the open Atlantic may be similarly affected, since the M2 discontinuity, but not the long-term secular increase in the tide, is evident also at Halifax.

Long-Term Warming Trends in Korea and Contribution of Urbanization: An Updated Assessment

NASA Astrophysics Data System (ADS)

Park, Bo-Joung; Kim, Yeon-Hee; Min, Seung-Ki; Kim, Maeng-Ki; Choi, Youngeun; Boo, Kyung-On; Shim, Sungbo

2017-10-01

This study conducted an updated analysis of the long-term temperature trends over South Korea and reassessed the contribution of the urbanization effect to the local warming trends. Linear trends were analyzed for three different periods over South Korea in order to consider possible inhomogeneity due to changes in the number of available stations: recent 103 years (1912-2014), 61 years (1954-2014), and 42 years (1973-2014). The local temperature has increased by 1.90°C, 1.35°C, and 0.99°C during the three periods, respectively, which are found 1.4-2.6 times larger than the global land mean trends. The countries located in the northern middle and high latitudes exhibit similar warming trends (about 1.5 times stronger than the global mean), suggesting a weak influence of urbanization on the local warming over South Korea. Urbanization contribution is assessed using two methods. First, results from "city minus rural" methods showed that 30-45% of the local warming trends during recent four decades are likely due to the urbanization effect, depending on station classification methods and analysis periods. Results from an "observation minus reanalysis" method using the Twentieth Century Reanalysis (20CR) data sets (v2 and v2c) indicated about 25-30% contribution of the urbanization effect to the local warming trend during the recent six decades. However, the urbanization contribution was estimated as low as 3-11% when considering the century-long period. Our results confirm large uncertainties in the estimation of urbanization contribution when using shorter-term periods and suggest that the urbanization contribution to the century-long warming trends could be much lower.

Warming experiments elucidate the drivers of observed directional changes in tundra vegetation

PubMed Central

Hollister, Robert D; May, Jeremy L; Kremers, Kelseyann S; Tweedie, Craig E; Oberbauer, Steven F; Liebig, Jennifer A; Botting, Timothy F; Barrett, Robert T; Gregory, Jessica L

2015-01-01

Few studies have clearly linked long-term monitoring with in situ experiments to clarify potential drivers of observed change at a given site. This is especially necessary when findings from a site are applied to a much broader geographic area. Here, we document vegetation change at Barrow and Atqasuk, Alaska, occurring naturally and due to experimental warming over nearly two decades. An examination of plant cover, canopy height, and community indices showed more significant differences between years than due to experimental warming. However, changes with warming were more consistent than changes between years and were cumulative in many cases. Most cases of directional change observed in the control plots over time corresponded with a directional change in response to experimental warming. These included increases in canopy height and decreases in lichen cover. Experimental warming resulted in additional increases in evergreen shrub cover and decreases in diversity and bryophyte cover. This study suggests that the directional changes occurring at the sites are primarily due to warming and indicates that further changes are likely in the next two decades if the regional warming trend continues. These findings provide an example of the utility of coupling in situ experiments with long-term monitoring to accurately document vegetation change in response to global change and to identify the underlying mechanisms driving observed changes. PMID:26140204

Long-term monitoring of change in Tropical grasslands- GLORIA network in the Andes

NASA Astrophysics Data System (ADS)

Cuesta, F. X.; Muriel, P.; Halloy, S.; Beck, S.; Meneses, R. I.; Irazabal, J.; Aguirre, N.; Viñas, P.; Suarez, D.; Becerra, M. T.; Gloria-Andes Network

2013-05-01

It has been shown that predicted warming and increased frequency of extreme weather events increase with altitude in the Andean mountains. Combined with enormous topographic (and hence precipitation) heterogeneity, poverty and intensive land use, creates in the region a situation of high vulnerability to global change. Since 2005 the network Global Research Initiative in Alpine Environment (GLORIA) sites have been progressively installed in Andean countries to monitor changes, document the type and magnitude of impacts and provide guidance to develop adaptation strategies for biodiversity, humans, and productive systems. We report the preliminary results from 10 of those sites, in addition to new sites planned in South America. These sites provide baseline data and identify processes and patterns in plant biodiversity across different geographic contexts. These preliminary results show the tremendous singularity of the vegetation and flora patterns in the study sites, suggesting high sensitivity of these ecosystems to climate anomalies. It is expected that the consolidation of this network will support and strengthen long-term observation and monitoring research programs to enable the documentation and understanding of climate change impacts on the Andean biota. Our research considers complementary modules of investigation (e.g. carbon stocks and fluxes, plant responses to experimental manipulation) that contextualize the challenges and opportunities of adaptation for biodiversity and socio-economic components, providing measures of trends as well as effectiveness of adaptive management strategies.

Decline in eelgrass ( Zostera marina L.) in Long Island Sound near Millstone Point, Connecticut (USA) unrelated to thermal input

NASA Astrophysics Data System (ADS)

Keser, Milan; Swenarton, John T.; Vozarik, Joseph M.; Foertch, James F.

2003-02-01

Eelgrass ( Zostera marina L.) shoot density, seed-bearing shoot abundance, shoot length, and standing stock biomass were monitored during summer months from 1985 to 2000 at three locations in eastern Long Island Sound (LIS) near Millstone Power Station (MPS), Waterford, Connecticut, USA. Short-term declines in eelgrass abundance were directly associated with fouling and overgrowth of eelgrass on two occasions; once by blue mussels ( Mytilus edulis) and once by a bloom of green algae ( Cladophora spp.). Analysis of long-term trends indicated some degree of decline in most of the parameters examined at all three areas monitored. The spatial relationship of the long-term eelgrass declines suggests primary causal factors other than the power plant discharge or regional climate change. Two populations to the east of MPS and near the fringes of the thermal plume (<1.5 km from the MPS discharge to LIS) exhibited only slight declines over the 16-y study period and thermal input from MPS to these sites was minimal (<1 °C above ambient conditions). By comparison, heavy eelgrass losses were documented in the Niantic River, located >2 km from the power plant thermal plume. Die-offs of entire individual eelgrass study beds in the Niantic River were observed on five separate occasions during the study with no sign of recovery. While the causes were not determined, anthropogenic influences such as nutrient loading from surface run-off and groundwater sources may have contributed to observed declines. The Niantic River has a more restricted tidal inlet and is closer to sources of nutrient enrichment than Jordan Cove. Historically, eelgrass has ranged to far western reaches of LIS, but over the last century has become restricted to the easternmost third of the Connecticut coastline due to nutrient loading and eutrophication of the western portions. This study suggests that the west-to-east declining trend in eelgrass distribution in LIS may be further progressing.

US army land condition-trend analysis (LCTA) program

NASA Astrophysics Data System (ADS)

Diersing, Victor E.; Shaw, Robert B.; Tazik, David J.

1992-05-01

The US Army Land Condition-Trend Analysis (LCTA) program is a standardized method of data collection, analysis, and reporting designed to meet multiple goals and objectives. The method utilizes vascular plant inventories, permanent field plot data, and wildlife inventories. Vascular plant inventories are used for environmental documentation, training of personnel, species identification during LCTA implementation, and as a survey for state and federal endangered or threatened species. The permanent field plot data documents the vegetational, edaphic, topographic, and disturbance characteristics of the installation. Inventory plots are allocated in a stratified random fashion across the installation utilizing a geographic information system that integrates satellite imagery and soil survey information. Ground cover, canopy cover, woody plant density, slope length, slope gradient, soil information, and disturbance data are collected at each plot. Plot data are used to: (1) describe plant communities, (2) characterize wildlife and threatened and endangered species habitat, (3) document amount and kind of military and nonmilitary disturbance, (4) determine the impact of military training on vegetation and soil resources, (5) estimate soil erosion potential, (6) classify land as to the kind and amount of use it can support, (7) determine allowable use estimates for tracked vehicle training, (8) document concealment resources, (9) identify lands that require restoration and evaluate the effectiveness of restorative techniques, and (10) evaluate potential acquisition property. Wildlife inventories survey small and midsize mammals, birds, bats, amphibians, and reptiles. Data from these surveys can be used for environmental documentation, to identify state and federal endangered and threatened species, and to evaluate the impact of military activities on wildlife populations. Short- and long-term monitoring of permanent field plots is used to evaluate and adjust land management decisions.

Identification of long-term trends and seasonality in high-frequency water quality data from the Yangtze River basin, China.

PubMed

Duan, Weili; He, Bin; Chen, Yaning; Zou, Shan; Wang, Yi; Nover, Daniel; Chen, Wen; Yang, Guishan

2018-01-01

Comprehensive understanding of the long-term trends and seasonality of water quality is important for controlling water pollution. This study focuses on spatio-temporal distributions, long-term trends, and seasonality of water quality in the Yangtze River basin using a combination of the seasonal Mann-Kendall test and time-series decomposition. The used weekly water quality data were from 17 environmental stations for the period January 2004 to December 2015. Results show gradual improvement in water quality during this period in the Yangtze River basin and greater improvement in the Uppermost Yangtze River basin. The larger cities, with high GDP and population density, experienced relatively higher pollution levels due to discharge of industrial and household wastewater. There are higher pollution levels in Xiang and Gan River basins, as indicated by higher NH4-N and CODMn concentrations measured at the stations within these basins. Significant trends in water quality were identified for the 2004-2015 period. Operations of the three Gorges Reservoir (TGR) enhanced pH fluctuations and possibly attenuated CODMn, and NH4-N transportation. Finally, seasonal cycles of varying strength were detected for time-series of pollutants in river discharge. Seasonal patterns in pH indicate that maxima appear in winter, and minima in summer, with the opposite true for CODMn. Accurate understanding of long-term trends and seasonality are necessary goals of water quality monitoring system efforts and the analysis methods described here provide essential information for effectively controlling water pollution.

Timescales for determining temperature and dissolved oxygen trends in the Long Island Sound (LIS) estuary

NASA Astrophysics Data System (ADS)

Staniec, Allison; Vlahos, Penny

2017-12-01

Long-term time series represent a critical part of the oceanographic community's efforts to discern natural and anthropogenically forced variations in the environment. They provide regular measurements of climate relevant indicators including temperature, oxygen concentrations, and salinity. When evaluating time series, it is essential to isolate long-term trends from autocorrelation in data and noise due to natural variability. Herein we apply a statistical approach, well-established in atmospheric time series, to key parameters in the U.S. east coast's Long Island Sound estuary (LIS). Analysis shows that the LIS time series (established in the early 1990s) is sufficiently long to detect significant trends in physical-chemical parameters including temperature (T) and dissolved oxygen (DO). Over the last two decades, overall (combined surface and deep) LIS T has increased at an average rate of 0.08 ± 0.03 °C yr-1 while overall DO has dropped at an average rate of 0.03 ± 0.01 mg L-1yr-1 since 1994 at the 95% confidence level. This trend is notably faster than the global open ocean T trend (0.01 °C yr-1), as might be expected for a shallower estuarine system. T and DO trends were always significant for the existing time series using four month data increments. Rates of change of DO and T in LIS are strongly correlated and the rate of decrease of DO concentrations is consistent with the expected reduced solubility of DO at these higher temperatures. Thus, changes in T alone, across decadal timescales can account for between 33 and 100% of the observed decrease in DO. This has significant implications for other dissolved gases and the long-term management of LIS hypoxia.

European temperature records of the past five centuries based on documentary information compared to climate simulations

NASA Astrophysics Data System (ADS)

Zorita, E.

2009-09-01

Two European temperature records for the past half-millennium, January-to-April air temperature for Stockholm (Sweden) and seasonal temperature for a Central European region, both derived from the analysis of documentary sources combined with long instrumental records, are compared with the output of forced (solar, volcanic, greenhouse gases) climate simulations with the model ECHO-G. The analysis is complemented with the long (early)-instrumental record of Central England Temperature (CET). Both approaches to study past climates (simulations and reconstructions) are burdened with uncertainties. The main objective of this comparative analysis is to identify robust features and weaknesses that may help to improve models and reconstruction methods. The results indicate a general agreement between simulations and the reconstructed Stockholm and CET records regarding the long-term temperature trend over the recent centuries, suggesting a reasonable choice of the amplitude of the solar forcing in the simulations and sensitivity of the model to the external forcing. However, the Stockholm reconstruction and the CET record also show a long and clear multi-decadal warm episode peaking around 1730, which is absent in the simulations. The uncertainties associated with the reconstruction method or with the simulated internal climate variability cannot easily explain this difference. Regarding the interannual variability, the Stockholm series displays in some periods higher amplitudes than the simulations but these differences are within the statistical uncertainty and further decrease if output from a regional model driven by the global model is used. The long-term trends in the simulations and reconstructions of the Central European temperature agree less well. The reconstructed temperature displays, for all seasons, a smaller difference between the present climate and past centuries than the simulations. Possible reasons for these differences may be related to a limitation of the traditional technique for converting documentary evidence to temperature values to capture long-term climate changes, because the documents often reflect temperatures relative to the contemporary authors' own perception of what constituted 'normal' conditions. By contrast, the simulated and reconstructed inter-annual variability is in rather good agreement.

Detection time for global and regional sea level trends and accelerations

NASA Astrophysics Data System (ADS)

Jordà, G.

2014-10-01

Many studies analyze trends on sea level data with the underlying purpose of finding indications of a long-term change that could be interpreted as the signature of anthropogenic climate change. The identification of a long-term trend is a signal-to-noise problem where the natural variability (the "noise") can mask the long-term trend (the "signal"). The signal-to-noise ratio depends on the magnitude of the long-term trend, on the magnitude of the natural variability, and on the length of the record, as the climate noise is larger when averaged over short time scales and becomes smaller over longer averaging periods. In this paper, we evaluate the time required to detect centennial sea level linear trends and accelerations at global and regional scales. Using model results and tide gauge observations, we find that the averaged detection time for a centennial linear trend is 87.9, 76.0, 59.3, 40.3, and 25.2 years for trends of 0.5, 1.0, 2.0, 5.0, and 10.0 mm/yr, respectively. However, in regions with large decadal variations like the Gulf Stream or the Circumpolar current, these values can increase up to a 50%. The spatial pattern of the detection time for sea level accelerations is almost identical. The main difference is that the length of the records has to be about 40-60 years longer to detect an acceleration than to detect a linear trend leading to an equivalent change after 100 years. Finally, we have used a new sea level reconstruction, which provides a more accurate representation of interannual variability for the last century in order to estimate the detection time for global mean sea level trends and accelerations. Our results suggest that the signature of natural variability in a 30 year global mean sea level record would be less than 1 mm/yr. Therefore, at least 2.2 mm/yr of the recent sea level trend estimated by altimetry cannot be attributed to natural multidecadal variability. This article was corrected on 19 NOV 2014. See the end of the full text for details.

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

Smith, L.L.; Hooper, M.

This report summarizes the activities and results for the second testing phase (Phase 2) of an Innovative Clean Coal Technology (ICCT) demonstration of advanced tangentially fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. All three levels of Asea Brown Boveri Combustion Engineering Service`s (ABB CE`s) Low-NO{sub x} Concentric Firing System (LNCFS) are being demonstrated during this project. The primary goal of this project is to demonstrate the NO{sub x} emissions characteristics of these technologies when operated under normal load dispatched conditions. The equipment is being tested at Gulf Power Company`s Plant Lansing Smith Unitmore » 2 in Lynn Haven, Florida. The long-term NO{sub x} emission trends were documented while the unit was operating under normal load dispatch conditions with the LNCFS Level II equipment. Fifty-five days of long-term data were collected. The data included the effects of mill patterns, unit load, mill outages, weather, fuel variability, and load swings. Test results indicated full-load (180 MW) NO{sub x} emissions of 0.39 lb/MBtu, which is about equal to the short-term test results. At 110 MW, long-term NO{sub x} emissions increased to 0.42 lb/MBtu, which are slightly higher than the short-term data. At 75 MW, NO{sub x} emissions were 0.51 lb/MBtu, which is significantly higher than the short-term data. The annual and 30-day average achievable NOx emissions were determined to be 0.41 and 0.45 lb/MBtu, respectively, for long-term testing load scenarios. NO{sub x} emissions were reduced by a maximum of 40 percent when compared to the baseline data collected in the previous phase. The long-term NO{sub x} reduction at full load (180 MW) was 37 percent while NO{sub x} reduction at low load was minimal.« less

Population cycles are highly correlated over long time series and large spatial scales in two unrelated species: Greater sage-grouse and cottontail rabbits

USGS Publications Warehouse

Fedy, B.C.; Doherty, K.E.

2011-01-01

Animal species across multiple taxa demonstrate multi-annual population cycles, which have long been of interest to ecologists. Correlated population cycles between species that do not share a predator-prey relationship are particularly intriguing and challenging to explain. We investigated annual population trends of greater sage-grouse (Centrocercus urophasianus) and cottontail rabbits (Sylvilagus sp.) across Wyoming to explore the possibility of correlations between unrelated species, over multiple cycles, very large spatial areas, and relatively southern latitudes in terms of cycling species. We analyzed sage-grouse lek counts and annual hunter harvest indices from 1982 to 2007. We show that greater sage-grouse, currently listed as warranted but precluded under the US Endangered Species Act, and cottontails have highly correlated cycles (r = 0. 77). We explore possible mechanistic hypotheses to explain the synchronous population cycles. Our research highlights the importance of control populations in both adaptive management and impact studies. Furthermore, we demonstrate the functional value of these indices (lek counts and hunter harvest) for tracking broad-scale fluctuations in the species. This level of highly correlated long-term cycling has not previously been documented between two non-related species, over a long time-series, very large spatial scale, and within more southern latitudes. ?? 2010 US Government.

On long-term ozone trends at Hohenpeissenberg

NASA Technical Reports Server (NTRS)

Claude, H.; Vandersee, W.; Wege, K.

1994-01-01

More than 2000 ozone soundings and a large number of Dobson observations have been performed since 1967 in a unique procedure. The achieved very homogeneous data sets were used to evaluate significant long-term trends both in the troposphere and the stratosphere. The trend amounts to about plus 2 percent per year in the troposphere and to about minus 0.5 percent per year in the stratosphere. Extremely low ozone records obtained during winter 1991/92 are discussed in the light of the long term series. The winter mean of the ozone column is the lowest one of the series. The ozone deficit occurred mainly in the lower stratosphere. One cause may be the Pinatubo cloud. Even compared with the extreme winter mean following the El Chichon eruption the ozone content was lower. Additionally ozone was reduced by dynamical effects due to unusual weather situations.

Extended rotations and culmination age of coast douglas-fir: Old studies speak to current issues. Forest Service research paper

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

Curtis, R.O.

1995-11-01

Trends of mean annual increment and periodic annual increment were examined in 17 long-term thinning studies in Douglas-fir (Pseuditsuga menziesii var. menziesii (Mirb.) Franco) in western Washington, western Oregon, and British Columbia. Problems in evaluating growth trends and culmination ages are discussed. None of the stands had clearly reached culmination of mean annual increment, although some seemed close. The observed trends seem generally consistent with some other recent comparisons. These comparisons indicate that rotations can be considerably extended without reducing long-term timber production; value production probably would increase. A major problem in such a strategy is design of thinning regimesmore » that can maintain a reasonable level of timber flow during the transition period while producing stand conditions compatible with other management objectives. The continuing value of long-term permanent plot studies is emphasized.« less

Long-Term Care for People with Development Disabilities: A Critical Analysis.

ERIC Educational Resources Information Center

Palley, Howard A.; Van Hollen, Valerie

2000-01-01

Explores how the trends toward long-term community care affecting people with developmental disabilities developed. Appropriateness of care and quality of life issues are discussed. Reviews the development of long-term care for frail and disabled elderly people and explores the arguments for a continuum of care that have developed in this area.…

Comparison of long-term trends from reanalyses

NASA Astrophysics Data System (ADS)

Kozubek, M.

2017-12-01

The long-term trend of different atmospheric parameters has been studied separately during previous years in many papers. This study is focused on the temperature, wind (u and v component), geopotential height and water vapour trends during 1979-2016. We present the trend for each month with respect to ozone turnaround during mid 1990s. The different reanalyses (MERRA, ERA-Interim, JRA-55 and NCEP-NOE) are used for comparison. We analyzed every grid point to reduce the problem with zonal averages in different pressure levels. The results will show the complex view on the trend in the middle atmosphere (troposphere, stratosphere and lower mesosphere). This comparison can give us the clue which reanalysis is better for studying different phenomena (QBO, NAO, ENSO, etc.) and which one has some issues.

Long-term trends and spatial patterns of PM2.5-induced premature mortality in South and Southeast Asia from 1999 to 2014.

PubMed

Shi, Yusheng; Matsunaga, Tsuneo; Yamaguchi, Yasushi; Zhao, Aimei; Li, Zhengqiang; Gu, Xingfa

2018-08-01

Fine particulate matter (PM 2.5 ) poses a potential threat to human health, including premature mortality under long-term exposure. Based on a long-term series of high-resolution (0.01°×0.01°) satellite-retrieved PM 2.5 concentrations, this study estimated the premature mortality attributable to PM 2.5 in South and Southeast Asia (SSEA) from 1999 to 2014. Then, the long-term trends and spatial characteristics of PM 2.5 -induced premature deaths (1999-2014) were analyzed using trend analyses and standard deviation ellipses. Results showed the estimated number of PM 2.5 -induced average annual premature deaths in SSEA was 1,447,000. The numbers increased from 1,179,400 in 1999 to 1,724,900 in 2014, with a growth rate of 38% and net increase of 545,500. Stroke and ischemic heart disease were the two principal contributors, accounting for 39% and 35% of the total, respectively. High values were concentrated in North India, Bangladesh, East Pakistan, and some metropolitan areas of Southeast Asia. An estimated 991,600 deaths in India was quantified (i.e., ~69% of the total premature deaths in SSEA). The long-term trends (1999-2014) of PM 2.5 -related premature mortality exhibited consistent incremental tendencies in all countries except Sri Lanka. The findings of this study suggest that strict controls of PM 2.5 concentrations in SSEA are urgently required. Copyright © 2018 Elsevier B.V. All rights reserved.

BIOTECHNOLOGY/ECORISK

EPA Science Inventory

This research effort is designed to provide the risk assessment community with modern genetic tools for evaluating long-term risks of genetically modified (GM) crops. Molecular population genetic data can potentially reveal information about long-term trends in both pest populat...

Guidance for practitioners on the use of antiviral drugs to control influenza outbreaks in long-term care facilities in Canada, 2014-2015 season.

PubMed

Aoki, Fred Y; Allen, Upton D; Stiver, H Grant; Laverdière, Michel; Skowronski, Danuta; Evans, Gerald A

2015-01-01

The AMMI Canada Guidelines document 'The use of antiviral drugs for influenza: A foundation document for practitioners', published in the Autumn 2013 issue of the Journal, outlines the recommendations for the use of antiviral drugs to treat influenza. This article, which represents the first of two updates to these guidelines published in the current issue of the Journal, aims to inform health care professionals of the increased risk for influenza in long-term care facilities due to a documented mismatch between the components chosen for this season's vaccine and currently circulating influenza strains. Adjusted recommendations for the use of antiviral drugs for influenza in long-term care facilities for this season are provided.

Issues in the Development of Long Term Care Gerontology Centers: The Centers Concept. Selected Topics in Long Term Care. Volume 6.

ERIC Educational Resources Information Center

Mortenson, Lee E.; Berdes, Celia M.

This document, one in a series developed to provide technical assistance to 22 Long-Term Care Gerontology Centers, describes the current administrative and structural phenomenon of these centers. Precedents useful in assessing both the current climate and actual prospects for development of long term care centers are cited. The first section…

Long-term trends in stratospheric ozone, temperature, and water vapor over the Indian region

NASA Astrophysics Data System (ADS)

Thankamani Akhil Raj, Sivan; Venkat Ratnam, Madineni; Narayana Rao, Daggumati; Venkata Krishna Murthy, Boddam

2018-01-01

We have investigated the long-term trends in and variabilities of stratospheric ozone, water vapor and temperature over the Indian monsoon region using the long-term data constructed from multi-satellite (Upper Atmosphere Research Satellite (UARS MLS and HALOE, 1993-2005), Aura Microwave Limb Sounder (MLS, 2004-2015), Sounding of the Atmosphere using Broadband Emission Radiometry (SABER, 2002-2015) on board TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics)) observations covering the period 1993-2015. We have selected two locations, namely, Trivandrum (8.4° N, 76.9° E) and New Delhi (28° N, 77° E), covering northern and southern parts of the Indian region. We also used observations from another station, Gadanki (13.5° N, 79.2° E), for comparison. A decreasing trend in ozone associated with NOx chemistry in the tropical middle stratosphere is found, and the trend turned to positive in the upper stratosphere. Temperature shows a cooling trend in the stratosphere, with a maximum around 37 km over Trivandrum (-1.71 ± 0.49 K decade-1) and New Delhi (-1.15 ± 0.55 K decade-1). The observed cooling trend in the stratosphere over Trivandrum and New Delhi is consistent with Gadanki lidar observations during 1998-2011. The water vapor shows a decreasing trend in the lower stratosphere and an increasing trend in the middle and upper stratosphere. A good correlation between N2O and O3 is found in the middle stratosphere (˜ 10 hPa) and poor correlation in the lower stratosphere. There is not much regional difference in the water vapor and temperature trends. However, upper stratospheric ozone trends over Trivandrum and New Delhi are different. The trend analysis carried out by varying the initial year has shown significant changes in the estimated trend.

46 CFR 356.43 - Long-term or exclusive sales contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... DOCUMENTATION Charters, Management Agreements and Exclusive or Long-Term Contracts § 356.43 Long-term or exclusive sales contracts. (a) An owner or bareboat charterer of a Fishing Industry Vessel may enter into an... a specified period of time. Such contracts or agreements will not require our prior approval...

33 CFR 332.4 - Planning and documentation.

Code of Federal Regulations, 2010 CFR

2010-07-01

....g., typical channel cross-sections), watershed size, design discharge, and riparian area plantings... achieved to ensure the long-term sustainability of the resource, including long-term financing mechanisms...

Eocene Temperature Evolution of the Tropical Atlantic Ocean

NASA Astrophysics Data System (ADS)

Cramwinckel, M.; Kocken, I.; Agnini, C.; Huber, M.; van der Ploeg, R.; Frieling, J.; Bijl, P.; Peterse, F.; Roehl, U.; Bohaty, S. M.; Schouten, S.; Sluijs, A.

2016-12-01

The transition from the early Eocene ( 50 Ma) hothouse towards the Oligocene ( 33 Ma) icehouse was interrupted by the Middle Eocene Climatic Optimum (MECO) ( 40 Ma), a 500,000-year long episode of deep sea and Southern Ocean warming. It remains unclear whether this transient warming event was global, and whether it was caused by changes in atmospheric greenhouse gas concentrations or confined to high latitudes resulting from ocean circulation change. Here we show, based on biomarker paleothermometry applied at Ocean Drilling Program Site 959, offshore Ghana, that sea surface temperatures in the eastern equatorial Atlantic Ocean declined by 7°C over the middle-late Eocene, in agreement with temperature trends documented in the southern high latitudes. In the equatorial Atlantic, this long-term trend was punctuated by 2.5°C warming during the MECO. At the zenith of MECO warmth, changes in dinoflagellate cyst assemblages and laminated sediments at Site 959 point to open ocean hyperstratification and seafloor deoxygenation, respectively. Remarkably, the data reveal that the magnitude of temperature change in the tropics was approximately half that in the Southern Ocean. This suggests that the generally ice free Eocene yielded limited but significant polar amplification of climate change. Crucially, general circulation model (GCM) simulations reveal that the recorded tropical and deep ocean temperature trends are best explained by greenhouse gas forcing, controlling both middle-late Eocene cooling and the superimposed MECO warming.

Variability analysis of the reconstructed daily global solar radiation under all-sky and cloud-free conditions in Madrid during the period 1887-1950

NASA Astrophysics Data System (ADS)

Antón, M.; Román, R.; Sanchez-Lorenzo, A.; Calbó, J.; Vaquero, J. M.

2017-07-01

This study focuses on the analysis of the daily global solar radiation (GSR) reconstructed from sunshine duration measurements at Madrid (Spain) from 1887 to 1950. Additionally, cloud cover information recorded simultaneously by human observations for the study period was also analyzed and used to select cloud-free days. First, the day-to-day variability of reconstructed GSR data was evaluated, finding a strong relationship between GSR and cloudiness. The second step was to analyze the long-term evolution of the GSR data which exhibited two clear trends with opposite sign: a marked negative trend of - 36 kJ/m2 per year for 1887-1915 period and a moderate positive trend of + 13 kJ/m2 per year for 1916-1950 period, both statistically significant at the 95% confidence level. Therefore, there is evidence of "early dimming" and "early brightening" periods in the reconstructed GSR data for all-sky conditions in Madrid from the late 19th to the mid-20th centuries. Unlike the long-term evolution of GSR data, cloud cover showed non-statistically significant trends for the two analyzed sub-periods, 1887-1915 and 1916-1950. Finally, GSR trends were analyzed exclusively under cloud-free conditions in summer by means of the determination of the clearness index for those days with all cloud cover observations equal to zero oktas. The long-term evolution of the clearness index was in accordance with the "early dimming" and "early brightening" periods, showing smaller trends but still statistically significant. This result points out that aerosol load variability could have had a non-negligible influence on the long-term evolution of GSR even as far as from the late 19th century.

Long-term meteorologically independent trend analysis of ozone air quality at an urban site in the greater Houston area.

PubMed

Botlaguduru, Venkata S V; Kommalapati, Raghava R; Huque, Ziaul

2018-04-19

The Houston-Galveston-Brazoria (HGB) area of Texas has a history of ozone exceedances and is currently classified under moderate nonattainment status for the 2008 8-hr ozone standard of 75 ppb. The HGB area is characterized by intense solar radiation, high temperature, and humidity, which influence day-to-day variations in ozone concentrations. Long-term air quality trends independent of meteorological influence need to be constructed for ascertaining the effectiveness of air quality management in this area. The Kolmogorov-Zurbenko (KZ) filter technique used to separate different scales of motion in a time series, is applied in the current study for maximum daily 8-hr (MDA8) ozone concentrations at an urban site (EPA AQS Site ID: 48-201-0024, Aldine) in the HGB area. This site located within 10 miles of downtown Houston and the George Bush Intercontinental Airport, was selected for developing long-term meteorologically independent MDA8 ozone trends for the years 1990-2016. Results from this study indicate a consistent decrease in meteorologically independent MDA8 ozone between 2000-2016. This pattern could be partially attributed to a reduction in underlying NO X emissions, particularly that of lowering nitrogen dioxide (NO 2 ) levels, and a decrease in the release of highly reactive volatile organic compounds (HRVOC). Results also suggest solar radiation to be most strongly correlated to ozone, with temperature being the secondary meteorological control variable. Relative humidity and wind speed have tertiary influence at this site. This study observed that meteorological variability accounts for a high of 61% variability in baseline ozone (low-frequency component, sum of long-term and seasonal components), while 64% of the change in long-term MDA8 ozone post-2000 could be attributed to NO X emissions reduction. Long-term MDA8 ozone trend component was estimated to be decreasing at a linear rate of 0.412 ± 0.007 ppb/yr for the years 2000-2016, and 0.155 ± 0.005 ppb/yr for the overall period of 1990-2016. Implications Statement The effectiveness of air emission controls can be evaluated by developing long-term air quality trends independent of meteorological influences. KZ filter technique is a well-established method to separate an air quality time-series into: short-term, seasonal and long-term components. This paper applies the KZ filter technique to MDA8 ozone data between 1990-2016 at an urban site in the Greater Houston area and estimates the variance accounted for, by the primary meteorological control variables. Estimates for linear trends of MDA8 ozone are calculated and underlying causes are investigated to provide a guidance for further investigation into air quality management of the Greater Houston Area.

Disparities in long-term care: building equity into market-based reforms.

PubMed

Konetzka, R Tamara; Werner, Rachel M

2009-10-01

A growing body of evidence documents pervasive racial, ethnic, and class disparities in long-term care in the United States. At the same time, major quality improvement initiatives are being implemented that rely on market-based incentives, many of which may have the unintended consequence of exacerbating disparities. We review existing evidence on disparities in the use and quality of long-term care services, analyze current market-based policy initiatives in terms of their potential to ameliorate or exacerbate these disparities, and suggest policies and policy modifications that may help decrease disparities. We find that racial disparities in the use of formal long-term care have decreased over time. Disparities in quality of care are more consistently documented and appear to be related to racial and socioeconomic segregation of long-term care facilities as opposed to within-provider discrimination. Market-based incentives policies should explicitly incorporate the goal of mitigating the potential unintended consequence of increased disparities.

Molecular Subtypes of Breast Cancer: Long-term Incidence Trends and Prognostic Differences.

PubMed

Valla, Marit; Vatten, Lars Johan; Engstrøm, Monica Jernberg; Haugen, Olav Anton; Akslen, Lars Andreas; Bjørngaard, Johan Håkon; Hagen, Anne Irene; Ytterhus, Borgny; Bofin, Anna Mary; Opdahl, Signe

2016-12-01

Secular trends in incidence and prognosis of molecular breast cancer subtypes are poorly described. We studied long-term trends in a population of Norwegian women born 1886-1977. A total of 52,949 women were followed for breast cancer incidence, and 1,423 tumors were reclassified into molecular subtypes using IHC and in situ hybridization. We compared incidence rates among women born 1886-1928 and 1929-1977, estimated age-specific incidence rate ratios (IRR), and performed multiple imputations to account for unknown subtype. Prognosis was compared for women diagnosed before 1995 and in 1995 or later, estimating cumulative risk of death and HRs. Between 50 and 69 years of age, incidence rates of Luminal A and Luminal B (HER2 - ) were higher among women born in 1929 or later, compared with before 1929 [IRRs 50-54 years; after imputations: 3.5; 95% confidence interval (CI), 1.8-6.9 and 2.5; 95% CI, 1.2-5.2, respectively], with no clear differences for other subtypes. Rates of death were lower in women diagnosed in 1995 or later, compared to before 1995, for Luminal A (HR 0.4; 95% CI, 0.3-0.5), Luminal B (HER2 - ; HR 0.5; 95% CI, 0.3-0.7), and Basal phenotype (HR 0.4; 95% CI, 0.2-0.9). We found a strong secular incidence increase restricted to Luminal A and Luminal B (HER2 - ) subtypes, combined with a markedly improved prognosis for these subtypes and for the Basal phenotype. This study documents a clear secular increase in incidence and a concomitant improved prognosis for specific molecular breast cancer subtypes. Cancer Epidemiol Biomarkers Prev; 25(12); 1625-34. ©2016 AACR. ©2016 American Association for Cancer Research.

O the Interpretation of Climatic Change from the Fossil Record: Climatic Change in Central and Eastern United States for the Past 2000 Years Estimated from Pollen Data.

NASA Astrophysics Data System (ADS)

Gajewski, Konrad J.

Pollen records from varved-lake sediments at seven locations in the northeastern United States record late Holocene climate changes over the past 1000-2000 years. Simplification of pollen diagrams by principal component analysis documents that climate changes affect vegetation at all sites, and not just at "sensitive" sites or ecotones. All seven pollen records show a long-term trend, medium frequency oscillations and higher frequency fluctuations. The between-site similarity of the trend and the coherency of the medium frequency oscillations demonstrates the importance of climate forcing to vegetation change at these scales. Response of vegetation to a climatic change is quite rapid, and depends not only on the nature of the climate fluctuation, but also on the pre-existing state of the vegetation. Multiple regression and canonical correlation techniques were used to calculate calibration functions from a spatial network of modern pollen and climate data. When analyzed at comparable scales, the spatial distribution of pollen assemblages in northeastern United States are related both to summer temperature and annual precipitation. Although summer temperature and annual precipitation are coupled, this coupling is not so strong as to negate the use of univariate calibration models. Over the 2000-year period of time, a gradual summer cooling of about 1.0(DEGREES)C/1000 years has occurred. Superimposed on the long-term trend are medium frequency temperature fluctuations of amplitude about 0.5(DEGREES)C that persist for several centuries. Annual precipitation is relatively constant, except for a period of increased rainfall from 600 years ago to the present in southern Maine.

Potential climate change impacts on a tropical estuary: Hilo Bay, Hawaii

NASA Astrophysics Data System (ADS)

Adolf, J.; LaPinta, J.; Marusek, J.; Pascoe, K.; Pugh, A.

2016-02-01

Hilo Bay is a tropical estuarine ecosystem on the northeast (windward) coast of Hawai`i Island that is potentially vulnerable to climate change effects mediated through elevated water temperatures and/or changing rainfall patterns that impact river and groundwater fluxes. Here, we document trends in water temperature, river flow and phytoplankton dynamics in Hilo Bay. Hilo Bay is fed by two major rivers, Wailuku and Honoli`i, both of which have shown long term declines in output over their 85 and 38 year monitoring periods (USGS), respectively. Time series of groundwater inputs to Hilo Bay do not exist, but the average estimated rate rivals that of average river inputs. Daily average Hilo Bay water temperatures have increased at a rate of 0.35 degrees C per year (p < 0.001) since measurement by the Hilo Bay water quality buoy began in 2010, with the warmest temperatures on record recorded Sept 2015. Salinity did not show a trend over this same time period. Phytoplankton showed a pronounced seasonal cycle in Hilo Bay with a long term average of 3.7 mg m-3 and dominance by diatoms that exploit the co-availability of silica and nitrate in this environment. On shorter time scales of days to < 1 week, flood events dramatically reduce Hilo Bay salinity, temperature and phytoplankton biomass. Coincidental atmospheric warming, SST warming in the adjacent North Pacific ocean, and declining river flows will likely work together to result in elevated SST in Hilo Bay if observed trends continue. The El Nino event that started this year is expected to exacerbate this warming through reduce river flow and warmer regional SST.

Plastic and evolutionary responses to climate change in fish

PubMed Central

Crozier, Lisa G; Hutchings, Jeffrey A

2014-01-01

The physical and ecological ‘fingerprints’ of anthropogenic climate change over the past century are now well documented in many environments and taxa. We reviewed the evidence for phenotypic responses to recent climate change in fish. Changes in the timing of migration and reproduction, age at maturity, age at juvenile migration, growth, survival and fecundity were associated primarily with changes in temperature. Although these traits can evolve rapidly, only two studies attributed phenotypic changes formally to evolutionary mechanisms. The correlation-based methods most frequently employed point largely to ‘fine-grained’ population responses to environmental variability (i.e. rapid phenotypic changes relative to generation time), consistent with plastic mechanisms. Ultimately, many species will likely adapt to long-term warming trends overlaid on natural climate oscillations. Considering the strong plasticity in all traits studied, we recommend development and expanded use of methods capable of detecting evolutionary change, such as the long term study of selection coefficients and temporal shifts in reaction norms, and increased attention to forecasting adaptive change in response to the synergistic interactions of the multiple selection pressures likely to be associated with climate change. PMID:24454549

Response of macroinvertebrate communities to temporal dynamics of pesticide mixtures: A case study from the Sacramento River watershed, California.

PubMed

Chiu, Ming-Chih; Hunt, Lisa; Resh, Vincent H

2016-12-01

Pesticide pollution from agricultural field run-off or spray drift has been documented to impact river ecosystems worldwide. However, there is limited data on short- and long-term effects of repeated pulses of pesticide mixtures on biotic assemblages in natural systems. We used reported pesticide application data as input to a hydrological fate and transport model (Soil and Water Assessment Tool) to simulate spatiotemporal dynamics of pesticides mixtures in streams on a daily time-step. We then applied regression models to explore the relationship between macroinvertebrate communities and pesticide dynamics in the Sacramento River watershed of California during 2002-2013. We found that both maximum and average pesticide toxic units were important in determining impacts on macroinvertebrates, and that the compositions of macroinvertebrates trended toward taxa having higher resilience and resistance to pesticide exposure, based on the Species at Risk pesticide (SPEAR pesticides ) index. Results indicate that risk-assessment efforts can be improved by considering both short- and long-term effects of pesticide mixtures on macroinvertebrate community composition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plastic and evolutionary responses to climate change in fish.

PubMed

Crozier, Lisa G; Hutchings, Jeffrey A

2014-01-01

The physical and ecological 'fingerprints' of anthropogenic climate change over the past century are now well documented in many environments and taxa. We reviewed the evidence for phenotypic responses to recent climate change in fish. Changes in the timing of migration and reproduction, age at maturity, age at juvenile migration, growth, survival and fecundity were associated primarily with changes in temperature. Although these traits can evolve rapidly, only two studies attributed phenotypic changes formally to evolutionary mechanisms. The correlation-based methods most frequently employed point largely to 'fine-grained' population responses to environmental variability (i.e. rapid phenotypic changes relative to generation time), consistent with plastic mechanisms. Ultimately, many species will likely adapt to long-term warming trends overlaid on natural climate oscillations. Considering the strong plasticity in all traits studied, we recommend development and expanded use of methods capable of detecting evolutionary change, such as the long term study of selection coefficients and temporal shifts in reaction norms, and increased attention to forecasting adaptive change in response to the synergistic interactions of the multiple selection pressures likely to be associated with climate change.

Long-term changes (1980-2003) in total ozone time series over Northern Hemisphere midlatitudes

NASA Astrophysics Data System (ADS)

Białek, Małgorzata

2006-03-01

Long-term changes in total ozone time series for Arosa, Belsk, Boulder and Sapporo stations are examined. For each station we analyze time series of the following statistical characteristics of the distribution of daily ozone data: seasonal mean, standard deviation, maximum and minimum of total daily ozone values for all seasons. The iterative statistical model is proposed to estimate trends and long-term changes in the statistical distribution of the daily total ozone data. The trends are calculated for the period 1980-2003. We observe lessening of negative trends in the seasonal means as compared to those calculated by WMO for 1980-2000. We discuss a possibility of a change of the distribution shape of ozone daily data using the Kolmogorov-Smirnov test and comparing trend values in the seasonal mean, standard deviation, maximum and minimum time series for the selected stations and seasons. The distribution shift toward lower values without a change in the distribution shape is suggested with the following exceptions: the spreading of the distribution toward lower values for Belsk during winter and no decisive result for Sapporo and Boulder in summer.

Examining the contribution of the observed global warming trend to the California droughts of 2012/13 and 2013/14

USGS Publications Warehouse

Funk, Christopher C.; Hoell, Andrew; Daithi Stone,

2014-01-01

While the SST trend mode has resulted in large SST increases that appear associated with an equatorial precipitation dipole response contrasting increases over the western Pacific and decreases over the central Pacific, the location of most of this warming is to the west of the key sensitivity areas identified in our CMIP5 composite. Removing this warming did not increase the CAM5 precipitation over California in a statistically significant manner, thus there appears to be little evidence that this long term warming trend contributed substantially to the 2013 and 2014 drought events. This result appears consistent with the lack of a long term downward trend in California precipitation. California precipitation does appear to be sensitive to north Pacific SST, and climate change models indicate substantial warming. If SST events like the unprecedented 2014 north Pacific SST anomaly become more common, California could also experience more frequent droughts. In addition, given the strong thermal control on evaporation, snowmelt, and water resources in California, the long-term warming is continuing to exert a growing stress on water availability.

Long term trending of engineering data for the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Cox, Ross M.

1993-01-01

A major goal in spacecraft engineering analysis is the detection of component failures before the fact. Trending is the process of monitoring subsystem states to discern unusual behaviors. This involves reducing vast amounts of data about a component or subsystem into a form that helps humans discern underlying patterns and correlations. A long term trending system has been developed for the Hubble Space Telescope. Besides processing the data for 988 distinct telemetry measurements each day, it produces plots of 477 important parameters for the entire 24 hours. Daily updates to the trend files also produce 339 thirty day trend plots each month. The total system combines command procedures to control the execution of the C-based data processing program, user-written FORTRAN routines, and commercial off-the-shelf plotting software. This paper includes a discussion the performance of the trending system and of its limitations.

40 CFR 230.94 - Planning and documentation.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-sections), watershed size, design discharge, and riparian area plantings. (8) Maintenance plan. A... sustainability of the resource, including long-term financing mechanisms and the party responsible for long-term...

Hawaiian forest bird trends: using log-linear models to assess long-term trends is supported by model diagnostics and assumptions (reply to Freed and Cann 2013)

USGS Publications Warehouse

Camp, Richard J.; Pratt, Thane K.; Gorresen, P. Marcos; Woodworth, Bethany L.; Jeffrey, John J.

2014-01-01

Freed and Cann (2013) criticized our use of linear models to assess trends in the status of Hawaiian forest birds through time (Camp et al. 2009a, 2009b, 2010) by questioning our sampling scheme, whether we met model assumptions, and whether we ignored short-term changes in the population time series. In the present paper, we address these concerns and reiterate that our results do not support the position of Freed and Cann (2013) that the forest birds in the Hakalau Forest National Wildlife Refuge (NWR) are declining, or that the federally listed endangered birds are showing signs of imminent collapse. On the contrary, our data indicate that the 21-year long-term trends for native birds in Hakalau Forest NWR are stable to increasing, especially in areas that have received active management.

Recovery from chronic and snowmelt acidification: Long-term trends in stream and soil water chemistry at the Hubbard Brook Experimental Forest, New Hampshire, USA

Treesearch

Colin B. Fuss; Charles T. Driscoll; John L. Campbell

2015-01-01

Atmospheric acid deposition of sulfate and nitrate has declined markedly in the northeastern United States due to emissions controls. We investigated long-term trends in soil water (1984–2011) and stream water (1982–2011) chemistry along an elevation gradient of a forested watershed to evaluate the progress of recovery of drainage waters from acidic deposition at the...

Long-term trends in climate and hydrology in an agricultural headwater watershed of central Pennsylvania, USA

Treesearch

Ray B. Bryant; Haiming Lu; Kyle R. Elkin; Anthony R. Buda; Amy S. Collick; Gordon J. Folmar; Peter J. Kleinman

2016-01-01

Climate change has emerged as a key issue facing agriculture and water resources in the US. Long-term (1968-2012) temperature, precipitation and streamflow data from a small (7.3 km2) watershed in east-central Pennsylvania was used to examine climatic and hydrologic trends in the context of recent climate change. Annual mean temperatures increased 0.38°C per decade,...

Long-term forecasting of internet backbone traffic.

PubMed

Papagiannaki, Konstantina; Taft, Nina; Zhang, Zhi-Li; Diot, Christophe

2005-09-01

We introduce a methodology to predict when and where link additions/upgrades have to take place in an Internet protocol (IP) backbone network. Using simple network management protocol (SNMP) statistics, collected continuously since 1999, we compute aggregate demand between any two adjacent points of presence (PoPs) and look at its evolution at time scales larger than 1 h. We show that IP backbone traffic exhibits visible long term trends, strong periodicities, and variability at multiple time scales. Our methodology relies on the wavelet multiresolution analysis (MRA) and linear time series models. Using wavelet MRA, we smooth the collected measurements until we identify the overall long-term trend. The fluctuations around the obtained trend are further analyzed at multiple time scales. We show that the largest amount of variability in the original signal is due to its fluctuations at the 12-h time scale. We model inter-PoP aggregate demand as a multiple linear regression model, consisting of the two identified components. We show that this model accounts for 98% of the total energy in the original signal, while explaining 90% of its variance. Weekly approximations of those components can be accurately modeled with low-order autoregressive integrated moving average (ARIMA) models. We show that forecasting the long term trend and the fluctuations of the traffic at the 12-h time scale yields accurate estimates for at least 6 months in the future.

Long-term monitoring of high-elevation white pine communities in Pacific West Region National Parks

Treesearch

Shawn T. McKinney; Tom Rodhouse; Les Chow; Penelope Latham; Daniel Sarr; Lisa Garrett; Linda Mutch

2011-01-01

National Park Service Inventory and Monitoring (I&M) networks conduct long-term monitoring to provide park managers information on the status and trends in key biological and environmental attributes (Vital Signs). Here we present an overview of a collaborative approach to long-term monitoring of high-elevation white pine forest dynamics among three Pacific West...

Common Calibration Source for Monitoring Long-term Ozone Trends

NASA Technical Reports Server (NTRS)

Kowalewski, Matthew

2004-01-01

Accurate long-term satellite measurements are crucial for monitoring the recovery of the ozone layer. The slow pace of the recovery and limited lifetimes of satellite monitoring instruments demands that datasets from multiple observation systems be combined to provide the long-term accuracy needed. A fundamental component of accurately monitoring long-term trends is the calibration of these various instruments. NASA s Radiometric Calibration and Development Facility at the Goddard Space Flight Center has provided resources to minimize calibration biases between multiple instruments through the use of a common calibration source and standardized procedures traceable to national standards. The Facility s 50 cm barium sulfate integrating sphere has been used as a common calibration source for both US and international satellite instruments, including the Total Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet 2 (SBUV/2) instruments, Shuttle SBUV (SSBUV), Ozone Mapping Instrument (OMI), Global Ozone Monitoring Experiment (GOME) (ESA), Scanning Imaging SpectroMeter for Atmospheric ChartographY (SCIAMACHY) (ESA), and others. We will discuss the advantages of using a common calibration source and its effects on long-term ozone data sets. In addition, sphere calibration results from various instruments will be presented to demonstrate the accuracy of the long-term characterization of the source itself.

Regional and temporal differences in nitrate trends discerned from long-term water quality monitoring data

USGS Publications Warehouse

Stets, Edward G.; Kelly, Valerie J.; Crawford, Charles G.

2015-01-01

Riverine nitrate (NO3) is a well-documented driver of eutrophication and hypoxia in coastal areas. The development of the elevated river NO3 concentration is linked to anthropogenic inputs from municipal, agricultural, and atmospheric sources. The intensity of these sources has varied regionally, through time, and in response to multiple causes such as economic drivers and policy responses. This study uses long-term water quality, land use, and other ancillary data to further describe the evolution of river NO3 concentrations at 22 monitoring stations in the United States (U.S.). The stations were selected for long-term data availability and to represent a range of climate and land-use conditions. We examined NO3 at the monitoring stations, using a flow-weighting scheme meant to account for interannual flow variability allowing greater focus on river chemical conditions. River NO3 concentration increased strongly during 1945-1980 at most of the stations and have remained elevated, but stopped increasing during 1981-2008. NO3 increased to a greater extent at monitoring stations in the Midwest U.S. and less so at those in the Eastern and Western U.S. We discuss 20th Century agricultural development in the U.S. and demonstrate that regional differences in NO3 concentration patterns were strongly related to an agricultural index developed using principal components analysis. This unique century-scale dataset adds to our understanding of long-term NO3 patterns in the U.S.

Long term trend and interannual variability of land carbon uptake — the attribution and processes

NASA Astrophysics Data System (ADS)

Fu, Zheng

2017-04-01

Ecosystem carbon (C) uptake in terrestrial ecosystems has increased over the past five decades, but with large interannual variability (IAV). However, we are not clear on the attribution and the processes that control the long-term trend and IAV of land C uptake. Using atmospheric inversion net ecosystem exchange (NEE) data, we quantified the trend and IAV of NEE across the globe, the Northern Hemisphere (NH), and the Southern Hemisphere (SH), and decomposed NEE into carbon uptake amplitude and duration during each year from 1979-2013. We found the NH rather than the SH determined the IAV, while both hemispheres contributed equivalently to the global NEE trend. Different ecosystems in the NH and SH had differential relative contributions to their trend and IAV. The long-term trends of increased C uptake across the globe and the SH were attributed to both extended duration and increasing amplitude of C uptake. The shortened duration of uptake in the NH partly offsets the effects of increased NEE amplitude, making the net C uptake trend the same as that of the SH. The change in NEE IAV was also linked to changes in the amplitude and duration of uptake, but they worked in different ways in the NH, SH and globe. The fundamental attributions of amplitude and duration of C uptake revealed in this study are helpful to better understand the mechanisms underlying the trend and IAV of land C uptake. Our findings also suggest the critical roles of grassland and croplands in the NH in contributing to the trend and IAV of land C uptake.

Long term trend and interannual variability of land carbon uptake—the attribution and processes

NASA Astrophysics Data System (ADS)

Fu, Zheng; Dong, Jinwei; Zhou, Yuke; Stoy, Paul C.; Niu, Shuli

2017-01-01

Ecosystem carbon (C) uptake in terrestrial ecosystems has increased over the past five decades, but with large interannual variability (IAV). However, we are not clear on the attribution and the processes that control the long-term trend and IAV of land C uptake. Using atmospheric inversion net ecosystem exchange (NEE) data, we quantified the trend and IAV of NEE across the globe, the Northern Hemisphere (NH), and the Southern Hemisphere (SH), and decomposed NEE into carbon uptake amplitude and duration during each year from 1979-2013. We found the NH rather than the SH determined the IAV, while both hemispheres contributed equivalently to the global NEE trend. Different ecosystems in the NH and SH had differential relative contributions to their trend and IAV. The long-term trends of increased C uptake across the globe and the SH were attributed to both extended duration and increasing amplitude of C uptake. The shortened duration of uptake in the NH partly offsets the effects of increased NEE amplitude, making the net C uptake trend the same as that of the SH. The change in NEE IAV was also linked to changes in the amplitude and duration of uptake, but they worked in different ways in the NH, SH and globe. The fundamental attributions of amplitude and duration of C uptake revealed in this study are helpful to better understand the mechanisms underlying the trend and IAV of land C uptake. Our findings also suggest the critical roles of grassland and croplands in the NH in contributing to the trend and IAV of land C uptake.

River-discharge variability and trends in southeastern Central Andes since 1940

NASA Astrophysics Data System (ADS)

Castino, Fabiana; Bookhagen, Bodo; Strecker, Manfred R.

2017-04-01

The southern Central Andes in NW Argentina comprise small to medium drainage basins (102-104 km2) particularly sensitive to climate variability. In this area and in contrast to larger drainage basins such as the Amazon or La Plata rivers, floodplains or groundwater reservoirs either do not exist or are small. This reduces their dampening effect on discharge variability. Previous studies highlighted a rapid discharge increase up to 40% in seven years in the southern Central Andes during the 1970s, inferred to have been associated with the global 1976-77 climate shift. To better understand the processes that drive variations in river discharge in this region, we analyze discharge variability on different timescales, relying on four time series of monthly discharge between 1940 and 2015. Since river discharge in this complex mountain environment results in a pronounced non-stationary and non-linear character, we apply the Hilbert-Huang Transform (HHT) to evaluate non-stationary oscillatory modes of variability and trends. An Ensemble Empirical Mode Decomposition (EEMD) analysis revealed that discharge variability in this region can be decomposed in four quasi-periodic, statistically significant oscillatory modes, associated with timescales varying from 1 to ˜20y. In addition, statistically significant long-term trends show increasing discharge during the period between 1940 and 2015, documenting an intensification of the hydrological cycle during this period. Furthermore, time-dependent intrinsic correlation (TDIC) analysis shows that discharge variability is most likely linked to the phases of the Pacific Decadal Oscillation (PDO) at multi-decadal timescales (˜20y) and, to a lesser degree, to the Tropical South Atlantic SST anomaly (TSA) variability at shorter timescales (˜2-5y). Finally, our results suggest that the rapid discharge increased occurred during the 1970s coincides with the periodic enhancement of discharge mainly linked to the rise of the PDO oscillation from the negative to the positive phase in superposition with the long-term increasing trend, further modulated by TSA variability.

Identification of long-term trends and seasonality in high-frequency water quality data from the Yangtze River basin, China

PubMed Central

He, Bin; Chen, Yaning; Zou, Shan; Wang, Yi; Nover, Daniel; Chen, Wen; Yang, Guishan

2018-01-01

Comprehensive understanding of the long-term trends and seasonality of water quality is important for controlling water pollution. This study focuses on spatio-temporal distributions, long-term trends, and seasonality of water quality in the Yangtze River basin using a combination of the seasonal Mann-Kendall test and time-series decomposition. The used weekly water quality data were from 17 environmental stations for the period January 2004 to December 2015. Results show gradual improvement in water quality during this period in the Yangtze River basin and greater improvement in the Uppermost Yangtze River basin. The larger cities, with high GDP and population density, experienced relatively higher pollution levels due to discharge of industrial and household wastewater. There are higher pollution levels in Xiang and Gan River basins, as indicated by higher NH4-N and CODMn concentrations measured at the stations within these basins. Significant trends in water quality were identified for the 2004–2015 period. Operations of the three Gorges Reservoir (TGR) enhanced pH fluctuations and possibly attenuated CODMn, and NH4-N transportation. Finally, seasonal cycles of varying strength were detected for time-series of pollutants in river discharge. Seasonal patterns in pH indicate that maxima appear in winter, and minima in summer, with the opposite true for CODMn. Accurate understanding of long-term trends and seasonality are necessary goals of water quality monitoring system efforts and the analysis methods described here provide essential information for effectively controlling water pollution. PMID:29466354

Evaluation of listener-based anuran surveys with automated audio recording devices

USGS Publications Warehouse

Shearin, A. F.; Calhoun, A.J.K.; Loftin, C.S.

2012-01-01

Volunteer-based audio surveys are used to document long-term trends in anuran community composition and abundance. Current sampling protocols, however, are not region- or species-specific and may not detect relatively rare or audibly cryptic species. We used automated audio recording devices to record calling anurans during 2006–2009 at wetlands in Maine, USA. We identified species calling, chorus intensity, time of day, and environmental variables when each species was calling and developed logistic and generalized mixed models to determine the time interval and environmental variables that optimize detection of each species during peak calling periods. We detected eight of nine anurans documented in Maine. Individual recordings selected from the sampling period (0.5 h past sunset to 0100 h) described in the North American Amphibian Monitoring Program (NAAMP) detected fewer species than were detected in recordings from 30 min past sunset until sunrise. Time of maximum detection of presence and full chorusing for three species (green frogs, mink frogs, pickerel frogs) occurred after the NAAMP sampling end time (0100 h). The NAAMP protocol’s sampling period may result in omissions and misclassifications of chorus sizes for certain species. These potential errors should be considered when interpreting trends generated from standardized anuran audio surveys.

Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in coastal waters of northern South China Sea.

PubMed

Wang, Xuefeng; Wang, Lifei; Jia, Xiaoping; Jackson, Donald A

2017-09-01

Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in the coastal waters of northern South China Sea were investigated in order to help improve the quality and safety control and sustainable aquaculture for mollusks in China. Cultured oysters (Crassostrea rivularis) collected from the waters of 23 bays, harbors, and estuaries along the coast of northern South China Sea from 1989 to 2012 were examined for spatial patterns and long-term temporal trends of oyster arsenic levels. Single-factor index and health risk assessment were used to quantify arsenic exposure to human health through oyster consumption. Overall, arsenic was detected in 97.4% of the oyster samples, and oyster arsenic levels were non-detectable-2.51 mg/kg with an average of 0.63 ± 0.54 mg/kg. Oyster arsenic levels in the coastal waters of northern South China Sea showed an overall decline from 1989 to 2012, remained relatively low since 2005, and slightly increased after 2007. Oyster arsenic levels in Guangdong coastal waters were much higher with more variation than in Guangxi and Hainan coastal waters, and the long-term trends of oyster arsenic levels in Guangdong coastal waters dominated the overall trends of oyster arsenic levels in the coastal waters of northern South China Sea. Within Guangdong Province, oyster arsenic levels were highest in east Guangdong coastal waters, followed by the Pearl River estuary and west Guangdong coastal waters. Single-factor index ranged between 0.27 and 0.97, and average health risk coefficient was 3.85 × 10 -5 , both suggesting that oyster arsenic levels in northern South China Sea are within the safe range for human consumption. However, long-term attention should be given to seafood market monitoring in China and the risk of arsenic exposure to human health through oyster consumption.

Pressure ulcer prevention in long-term-care facilities: a pilot study implementing standardized nurse aide documentation and feedback reports.

PubMed

Horn, Susan D; Sharkey, Siobhan S; Hudak, Sandra; Gassaway, Julie; James, Roberta; Spector, William

2010-03-01

To design and facilitate implementation of practice-based evidence changes associated with decreases in pressure ulcer (PrU) development in long-term-care (LTC) facilities and promote these practices as part of routine care. Pre/post observational study. Frail older adult residents in 11 US LTC facilities. Project facilitators assisted frontline multidisciplinary teams (certified nurse aides [CNAs], nurses, and dietitians/dietary aides) to develop streamlined standardized CNA documentation and weekly reports to identify high-risk residents and to integrate clinical reports into day-to-day practice and clinical decision making. The program was called "Real-Time Optimal Care Plans for Nursing Home QI" (Real-Time). Prevalence of PrUs using Centers for Medicare & Medicaid Services (CMS) quality measures (QMs), number of in-house-acquired PrUs, and number and completeness of CNA documentation forms. Seven study LTC facilities that reported data to CMS experienced a combined 33% (SD, 36.1%) reduction in the CMS high-risk PrU QM in 18 months and reduction in newly occurring PrUs (number of ulcers in the fourth quarter of 2003: range, 2-19; and in the third quarter of 2005: range, 1-6). Five of these LTC facilities that fully implemented Real-Time experienced a combined 48.1% (SD, 23.4%) reduction in the CMS high-risk PrU QM. Ten facilities reduced by an average of 2 to 5 their number of CNA documentation forms; CNA weekly documentation completeness reached a consistent level of 90% to 95%, and 8 facilities integrated the use of 2 to 4 weekly project reports in routine clinical decision making. Quality improvement efforts that provide access to focused and timely clinical information, facilitate change, and promote staff working together in multidisciplinary teams impacted clinical outcomes. Prevention of PrUs showed a trend of improvement in facilities that fully integrated tools to identify high-risk residents into day-to-day practice. CNA documentation facilitated better information for clinical decision making. More than 70 additional LTC facilities across the United States are implementing this QI program.

Long-term trends of surface ozone and its influencing factors at the Mt Waliguan GAW station, China - Part 1: Overall trends and characteristics

NASA Astrophysics Data System (ADS)

Xu, Wanyun; Lin, Weili; Xu, Xiaobin; Tang, Jie; Huang, Jianqing; Wu, Hao; Zhang, Xiaochun

2016-05-01

Tropospheric ozone is an important atmospheric oxidant, greenhouse gas and atmospheric pollutant at the same time. The oxidation capacity of the atmosphere, climate, human and vegetation health can be impacted by the increase of the ozone level. Therefore, long-term determination of trends of baseline ozone is highly needed information for environmental and climate change assessment. So far, studies on the long-term trends of ozone at representative sites are mainly available for European and North American sites. Similar studies are lacking for China and many other developing countries. Measurements of surface ozone were carried out at a baseline Global Atmospheric Watch (GAW) station in the north-eastern Tibetan Plateau region (Mt Waliguan, 36°17' N, 100°54' E, 3816 m a.s.l.) for the period of 1994 to 2013. To uncover the variation characteristics, long-term trends and influencing factors of surface ozone at this remote site in western China, a two-part study has been carried out, with this part focusing on the overall characteristics of diurnal, seasonal and long-term variations and the trends of surface ozone. To obtain reliable ozone trends, we performed the Mann-Kendall trend test and the Hilbert-Huang transform (HHT) analysis on the ozone data. Our results confirm that the mountain-valley breeze plays an important role in the diurnal cycle of surface ozone at Waliguan, resulting in higher ozone values during the night and lower ones during the day, as was previously reported. Systematic diurnal and seasonal variations were found in mountain-valley breezes at the site, which were used in defining season-dependent daytime and nighttime periods for trend calculations. Significant positive trends in surface ozone were detected for both daytime (0.24 ± 0.16 ppbv year-1) and nighttime (0.28 ± 0.17 ppbv year-1). The largest nighttime increasing rate occurred in autumn (0.29 ± 0.11 ppbv year-1), followed by spring (0.24 ± 0.12 ppbv year-1), summer (0.22 ± 0.20 ppbv year-1) and winter (0.13 ± 0.10 ppbv year-1), respectively. The HHT spectral analysis identified four different stages with different positive trends, with the largest increase occurring around May 2000 and October 2010. The HHT results suggest that there were 2-4a, 7a and 11a periodicities in the time series of surface ozone at Waliguan. The results of this study can be used for assessments of climate and environment change and in the validation of chemistry-climate models.

Solar Radiation and Tidal Exposure as Environmental Drivers of Enhalus acoroides Dominated Seagrass Meadows

PubMed Central

Unsworth, Richard K. F.; Rasheed, Michael A.; Chartrand, Kathryn M.; Roelofs, Anthony J.

2012-01-01

There is strong evidence of a global long-term decline in seagrass meadows that is widely attributed to anthropogenic activity. Yet in many regions, attributing these changes to actual activities is difficult, as there exists limited understanding of the natural processes that can influence these valuable ecosystem service providers. Being able to separate natural from anthropogenic causes of seagrass change is important for developing strategies that effectively mitigate and manage anthropogenic impacts on seagrass, and promote coastal ecosystems resilient to future environmental change. The present study investigated the influence of environmental and climate related factors on seagrass biomass in a large ≈250 ha meadow in tropical north east Australia. Annual monitoring of the intertidal Enhalus acoroides (L.f.) Royle seagrass meadow over eleven years revealed a declining trend in above-ground biomass (54% significant overall reduction from 2000 to 2010). Partial Least Squares Regression found this reduction to be significantly and negatively correlated with tidal exposure, and significantly and negatively correlated with the amount of solar radiation. This study documents how natural long-term tidal variability can influence long-term seagrass dynamics. Exposure to desiccation, high UV, and daytime temperature regimes are discussed as the likely mechanisms for the action of these factors in causing this decline. The results emphasise the importance of understanding and assessing natural environmentally-driven change when interpreting the results of seagrass monitoring programs. PMID:22479541

Similar and yet so different: cash-for-care in six European countries' long-term care policies.

PubMed

Da Roit, Barbara; Le Bihan, Blanche

2010-09-01

In response to increasing care needs, the reform or development of long-term care (LTC) systems has become a prominent policy issue in all European countries. Cash-for-care schemes-allowances instead of services provided to dependents-represent a key policy aimed at ensuring choice, fostering family care, developing care markets, and containing costs. A detailed analysis of policy documents and regulations, together with a systematic review of existing studies, was used to investigate the differences among six European countries (Austria, France, Germany, Italy, the Netherlands, and Sweden). The rationale and evolution of their various cash-for-care schemes within the framework of their LTC systems also were explored. While most of the literature present cash-for-care schemes as a common trend in the reforms that began in the 1990s and often treat them separately from the overarching LTC policies, this article argues that the policy context, timing, and specific regulation of the new schemes have created different visions of care and care work that in turn have given rise to distinct LTC configurations. A new typology of long-term care configurations is proposed based on the inclusiveness of the system, the role of cash-for-care schemes and their specific regulations, as well as the views of informal care and the care work that they require. © 2010 Milbank Memorial Fund. Published by Wiley Periodicals Inc.

Similar and Yet So Different: Cash-for-Care in Six European Countries’ Long-Term Care Policies

PubMed Central

Da Roit, Barbara; Le Bihan, Blanche

2010-01-01

Context: In response to increasing care needs, the reform or development of long-term care (LTC) systems has become a prominent policy issue in all European countries. Cash-for-care schemes—allowances instead of services provided to dependents—represent a key policy aimed at ensuring choice, fostering family care, developing care markets, and containing costs. Methods: A detailed analysis of policy documents and regulations, together with a systematic review of existing studies, was used to investigate the differences among six European countries (Austria, France, Germany, Italy, the Netherlands, and Sweden). The rationale and evolution of their various cash-for-care schemes within the framework of their LTC systems also were explored. Findings: While most of the literature present cash-for-care schemes as a common trend in the reforms that began in the 1990s and often treat them separately from the overarching LTC policies, this article argues that the policy context, timing, and specific regulation of the new schemes have created different visions of care and care work that in turn have given rise to distinct LTC configurations. Conclusions: A new typology of long-term care configurations is proposed based on the inclusiveness of the system, the role of cash-for-care schemes and their specific regulations, as well as the views of informal care and the care work that they require. PMID:20860573

Non-parametric characterization of long-term rainfall time series

NASA Astrophysics Data System (ADS)

Tiwari, Harinarayan; Pandey, Brij Kishor

2018-03-01

The statistical study of rainfall time series is one of the approaches for efficient hydrological system design. Identifying, and characterizing long-term rainfall time series could aid in improving hydrological systems forecasting. In the present study, eventual statistics was applied for the long-term (1851-2006) rainfall time series under seven meteorological regions of India. Linear trend analysis was carried out using Mann-Kendall test for the observed rainfall series. The observed trend using the above-mentioned approach has been ascertained using the innovative trend analysis method. Innovative trend analysis has been found to be a strong tool to detect the general trend of rainfall time series. Sequential Mann-Kendall test has also been carried out to examine nonlinear trends of the series. The partial sum of cumulative deviation test is also found to be suitable to detect the nonlinear trend. Innovative trend analysis, sequential Mann-Kendall test and partial cumulative deviation test have potential to detect the general as well as nonlinear trend for the rainfall time series. Annual rainfall analysis suggests that the maximum changes in mean rainfall is 11.53% for West Peninsular India, whereas the maximum fall in mean rainfall is 7.8% for the North Mountainous Indian region. The innovative trend analysis method is also capable of finding the number of change point available in the time series. Additionally, we have performed von Neumann ratio test and cumulative deviation test to estimate the departure from homogeneity. Singular spectrum analysis has been applied in this study to evaluate the order of departure from homogeneity in the rainfall time series. Monsoon season (JS) of North Mountainous India and West Peninsular India zones has higher departure from homogeneity and singular spectrum analysis shows the results to be in coherence with the same.

Skin Cancer, Irradiation, and Sunspots: The Solar Cycle Effect

PubMed Central

Zurbenko, Igor

2014-01-01

Skin cancer is diagnosed in more than 2 million individuals annually in the United States. It is strongly associated with ultraviolet exposure, with melanoma risk doubling after five or more sunburns. Solar activity, characterized by features such as irradiance and sunspots, undergoes an 11-year solar cycle. This fingerprint frequency accounts for relatively small variation on Earth when compared to other uncorrelated time scales such as daily and seasonal cycles. Kolmogorov-Zurbenko filters, applied to the solar cycle and skin cancer data, separate the components of different time scales to detect weaker long term signals and investigate the relationships between long term trends. Analyses of crosscorrelations reveal epidemiologically consistent latencies between variables which can then be used for regression analysis to calculate a coefficient of influence. This method reveals that strong numerical associations, with correlations >0.5, exist between these small but distinct long term trends in the solar cycle and skin cancer. This improves modeling skin cancer trends on long time scales despite the stronger variation in other time scales and the destructive presence of noise. PMID:25126567

Long-term trends in California mobile source emissions and ambient concentrations of black carbon and organic aerosol.

PubMed

McDonald, Brian C; Goldstein, Allen H; Harley, Robert A

2015-04-21

A fuel-based approach is used to assess long-term trends (1970-2010) in mobile source emissions of black carbon (BC) and organic aerosol (OA, including both primary emissions and secondary formation). The main focus of this analysis is the Los Angeles Basin, where a long record of measurements is available to infer trends in ambient concentrations of BC and organic carbon (OC), with OC used here as a proxy for OA. Mobile source emissions and ambient concentrations have decreased similarly, reflecting the importance of on- and off-road engines as sources of BC and OA in urban areas. In 1970, the on-road sector accounted for ∼90% of total mobile source emissions of BC and OA (primary + secondary). Over time, as on-road engine emissions have been controlled, the relative importance of off-road sources has grown. By 2010, off-road engines were estimated to account for 37 ± 20% and 45 ± 16% of total mobile source contributions to BC and OA, respectively, in the Los Angeles area. This study highlights both the success of efforts to control on-road emission sources, and the importance of considering off-road engine and other VOC source contributions when assessing long-term emission and ambient air quality trends.

A Global Model Simulation of Aerosol Effects of Surface Radiation Budget- Toward Understanding of the "Dimming to Brightening" Transition

NASA Technical Reports Server (NTRS)

Chin, Mian; Diehl, Thomas; Bian, Huisheng; Yu, Hongbin

2008-01-01

We present a global model study on the role aerosols play in the change of solar radiation at Earth's surface that transitioned from a decreasing (dimming) trend to an increasing (brightening) trend. Our primary objective is to understand the relationship between the long-term trends of aerosol emission, atmospheric burden, and surface solar radiation. More specifically, we use the recently compiled comprehensive global emission datasets of aerosols and precursors from fuel combustion, biomass burning, volcanic eruptions and other sources from 1980 to 2006 to simulate long-term variations of aerosol distributions and optical properties, and then calculate the multi-decadal changes of short-wave radiative fluxes at the surface and at the top of the atmosphere by coupling the GOCART model simulated aerosols with the Goddard radiative transfer model. The model results are compared with long-term observational records from ground-based networks and satellite data. We will address the following critical questions: To what extent can the observed surface solar radiation trends, known as the transition from dimming to brightening, be explained by the changes of anthropogenic and natural aerosol loading on global and regional scales? What are the relative contributions of local emission and long-range transport to the surface radiation budget and how do these contributions change with time?

Long Term Care: Report to the Secretary. Service Delivery Assessment, Office of the Inspector General, December 1981.

ERIC Educational Resources Information Center

Department of Health and Human Services, Seattle, WA. Region 10.

The demand for long term care is growing as the population in need of services becomes older and frailer, and as the nature of the family, the economy, and the health care system changes. To investigate the long term care system, its characteristics, trends, financing, policies, availability, and quality of care, 700 health care professionals,…

Rapidly increasing macroalgal cover not related to herbivorous fishes on Mesoamerican reefs

PubMed Central

Suchley, Adam; McField, Melanie D.

2016-01-01

Long-term phase shifts from coral to macroalgal dominated reef systems are well documented in the Caribbean. Although the impact of coral diseases, climate change and other factors is acknowledged, major herbivore loss through disease and overfishing is often assigned a primary role. However, direct evidence for the link between herbivore abundance, macroalgal and coral cover is sparse, particularly over broad spatial scales. In this study we use a database of coral reef surveys performed at 85 sites along the Mesoamerican Reef of Mexico, Belize, Guatemala and Honduras, to examine potential ecological links by tracking site trajectories over the period 2005–2014. Despite the long-term reduction of herbivory capacity reported across the Caribbean, the Mesoamerican Reef region displayed relatively low macroalgal cover at the onset of the study. Subsequently, increasing fleshy macroalgal cover was pervasive. Herbivorous fish populations were not responsible for this trend as fleshy macroalgal cover change was not correlated with initial herbivorous fish biomass or change, and the majority of sites experienced increases in macroalgae browser biomass. This contrasts the coral reef top-down herbivore control paradigm and suggests the role of external factors in making environmental conditions more favourable for algae. Increasing macroalgal cover typically suppresses ecosystem services and leads to degraded reef systems. Consequently, policy makers and local coral reef managers should reassess the focus on herbivorous fish protection and consider complementary measures such as watershed management in order to arrest this trend. PMID:27280075

Tropospheric ozone long term trend observed by lidar and ECC ozonesondes at Observatoire de Haute Provence, Southern France.

NASA Astrophysics Data System (ADS)

Ancellet, G.; Gaudel, A.; Godin-Beekmann, S.

2016-12-01

Tropospheric ozone vertical profile measurements have been carried out at OHP (Observatoire de Haute Provence, 44°N, 6.7°E, 690 m) since 1991 using both UV DIAL (DIfferential Absorption Lidar) and ECC (Electrochemical Concentration Cell) ozonesondes. For the first time, ECC and lidar data measured at the same site, have been compared over a 24 year period. The comparison conducted reveals a bias between both measurement types (ECC - lidar) of the order of 0.6 ppbv. The measurements of both instruments have been however combined to decrease the impact of short-term atmospheric variability on the trend estimate. Air mass trajectories have been calculated for all the ozone observations available at OHP including ECMWF potential vorticity (PV) and humidity chnage along the trajectories. The interannual ozone variability shows a negligible trend in the mid troposphere, but a 0.36 ppbv/year significant positive ozone trend in the upper troposphere. The trends will be discussed using the variability of the meteorological parameters. Data clustering using PV and air mass trajectories is useful to identify the role of Stratosphere-Tropopshere Exchanges and long range transport of pollutants in the observed long term trends. In the lower troposphere, the interannual variability shows contrasted trends with an ozone decrease between 1998 and 2008, consistent with the NOx emission decrease, but a new period of ozone increase since 2008 which is not very well understood.

A Summary of Research in Elementary, Secondary, and College Levels of Science Education for 1970.

ERIC Educational Resources Information Center

Trowbridge, Leslie W.; And Others

A review of 402 documents at all school levels is presented to identify current trends in science education research studies. The documents are limited to journal articles, dissertation abstracts, and abstracted reports, primarily appearing in 1970. Nature of the research conducted is analyzed in terms of curriculum improvement projects, learning…

Climate change in the Fertile Crescent and implications of the recent Syrian drought

PubMed Central

Kelley, Colin P.; Mohtadi, Shahrzad; Cane, Mark A.; Seager, Richard; Kushnir, Yochanan

2015-01-01

Before the Syrian uprising that began in 2011, the greater Fertile Crescent experienced the most severe drought in the instrumental record. For Syria, a country marked by poor governance and unsustainable agricultural and environmental policies, the drought had a catalytic effect, contributing to political unrest. We show that the recent decrease in Syrian precipitation is a combination of natural variability and a long-term drying trend, and the unusual severity of the observed drought is here shown to be highly unlikely without this trend. Precipitation changes in Syria are linked to rising mean sea-level pressure in the Eastern Mediterranean, which also shows a long-term trend. There has been also a long-term warming trend in the Eastern Mediterranean, adding to the drawdown of soil moisture. No natural cause is apparent for these trends, whereas the observed drying and warming are consistent with model studies of the response to increases in greenhouse gases. Furthermore, model studies show an increasingly drier and hotter future mean climate for the Eastern Mediterranean. Analyses of observations and model simulations indicate that a drought of the severity and duration of the recent Syrian drought, which is implicated in the current conflict, has become more than twice as likely as a consequence of human interference in the climate system. PMID:25733898

Climate change in the Fertile Crescent and implications of the recent Syrian drought.

PubMed

Kelley, Colin P; Mohtadi, Shahrzad; Cane, Mark A; Seager, Richard; Kushnir, Yochanan

2015-03-17

Before the Syrian uprising that began in 2011, the greater Fertile Crescent experienced the most severe drought in the instrumental record. For Syria, a country marked by poor governance and unsustainable agricultural and environmental policies, the drought had a catalytic effect, contributing to political unrest. We show that the recent decrease in Syrian precipitation is a combination of natural variability and a long-term drying trend, and the unusual severity of the observed drought is here shown to be highly unlikely without this trend. Precipitation changes in Syria are linked to rising mean sea-level pressure in the Eastern Mediterranean, which also shows a long-term trend. There has been also a long-term warming trend in the Eastern Mediterranean, adding to the drawdown of soil moisture. No natural cause is apparent for these trends, whereas the observed drying and warming are consistent with model studies of the response to increases in greenhouse gases. Furthermore, model studies show an increasingly drier and hotter future mean climate for the Eastern Mediterranean. Analyses of observations and model simulations indicate that a drought of the severity and duration of the recent Syrian drought, which is implicated in the current conflict, has become more than twice as likely as a consequence of human interference in the climate system.

Climate change in the Fertile Crescent and implications of the recent Syrian drought

NASA Astrophysics Data System (ADS)

Kelley, Colin P.; Mohtadi, Shahrzad; Cane, Mark A.; Seager, Richard; Kushnir, Yochanan

2015-03-01

Before the Syrian uprising that began in 2011, the greater Fertile Crescent experienced the most severe drought in the instrumental record. For Syria, a country marked by poor governance and unsustainable agricultural and environmental policies, the drought had a catalytic effect, contributing to political unrest. We show that the recent decrease in Syrian precipitation is a combination of natural variability and a long-term drying trend, and the unusual severity of the observed drought is here shown to be highly unlikely without this trend. Precipitation changes in Syria are linked to rising mean sea-level pressure in the Eastern Mediterranean, which also shows a long-term trend. There has been also a long-term warming trend in the Eastern Mediterranean, adding to the drawdown of soil moisture. No natural cause is apparent for these trends, whereas the observed drying and warming are consistent with model studies of the response to increases in greenhouse gases. Furthermore, model studies show an increasingly drier and hotter future mean climate for the Eastern Mediterranean. Analyses of observations and model simulations indicate that a drought of the severity and duration of the recent Syrian drought, which is implicated in the current conflict, has become more than twice as likely as a consequence of human interference in the climate system.

Forum for discussion and debate

NASA Technical Reports Server (NTRS)

1981-01-01

The application of statistical methods to meteorological data for which there are long, compatible series, and where known trend changes took place were suggested. The effects of optical wedge deterioration, atmospheric aerosol variation, solar irradiance variations, etc., are evaluated. It is recommended that coupled satellite ground based observational system is required to determine global long term trends.

The long-term trend in the diurnal temperature range over Asia and its natural and anthropogenic causes

NASA Astrophysics Data System (ADS)

Liu, Lin; Li, Zhanqing; Yang, Xin; Gong, Hainan; Li, Chao; Xiong, Anyuan

2016-04-01

Understanding the causes of long-term temperature trends is at the core of climate change studies. Any observed trend can result from natural variability or anthropogenic influences or both. In the present study, we evaluated the performance of 18 climate models from the Coupled Model Intercomparison Project Phase 5 on simulating the Asian diurnal temperature range (DTR) and explored the potential causes of the long-term trend in the DTR by examining the response of the DTR to natural forcing (volcanic aerosols and solar variability) and anthropogenic forcing (anthropogenic greenhouse gases (GHG) and aerosols) in the historical period of 1961-2005. For the climatology, the multimodel ensemble mean reproduced the geographical distribution and amplitude of the DTR over eastern China and India but underestimated the magnitudes of the DTR over the Tibetan Plateau and the high-latitude regions of the Asian continent. These negative biases in the DTR over frigid zones existed in most models. Seasonal biases in the DTR pattern from models were similar to the bias in the annual mean DTR pattern. Based on three selected state-of-the-art models, the observed decreasing trend in the DTR over Asia was reasonably reproduced in the all-forcing run. A comparison of separate forcing experiments revealed that anthropogenic forcing plays the dominant role in the declining trend in the DTR. Observations and model simulations showed that GHG forcing is mainly responsible for the negative trends in the DTR over Asia but that anthropogenic aerosol forcing was also behind the decreasing trend in the DTR over China and especially over eastern China.

Measurements of the Solar Spectral Irradiance Variability over Solar Cycles 21 to 24

NASA Astrophysics Data System (ADS)

Woods, T. N.

2017-12-01

The solar irradiance is the primary natural energy input into Earth's atmosphere and climate system. Understanding the long-term variations of the solar spectral irradiance (SSI) over time scales of the 11-year solar activity cycle and longer is critical for most Sun-climate research topics. There are satellite measurements of the SSI since the 1970s that contribute to understanding the solar cycle variability over Solar Cycles 21 to 24. A limiting factor for the accuracy of these results is the uncertainties for the instrument degradation corrections, for which there are fairly large corrections relative to the amount of solar cycle variability at some wavelengths. A summary of these satellite SSI measurements, which are primarily in the ultraviolet and only recently in the visible and near infrared, will be presented. Examining SSI trends using a new analysis technique is helping to identify some uncorrected instrumental trends, which once applied to the SSI trends has the potential to provide more accurate solar cycle variability results. This new technique examines the SSI trends at different levels of solar activity to provide long-term trends in a SSI record, and one of the most common components of these derived long-term trends is a downward trend that we attribute to being most likely from uncorrected instrument degradation. Examples of this analysis will be presented for some of the satellite SSI measurements to demonstrate this new technique and how it has potential to improve the understanding of solar cycle variability and to clarify the uncertainties of the trends.

Changes in erosion and flooding risk due to long-term and cyclic oceanographic trends

USGS Publications Warehouse

Wahl, Thomas; Plant, Nathaniel G.

2015-01-01

We assess temporal variations in waves and sea level, which are driving factors for beach 23 erosion and coastal flooding in the northern Gulf of Mexico. We find that long-term trends in 24 the relevant variables have caused an increase of ~30% in the erosion/flooding risk since the 25 1980s. Changes in the wave climate-which have often been ignored in earlier assessments-26 were at least as important as sea-level rise (SLR). In the next decades, SLR will likely become 27 the dominating driver and may in combination with ongoing changes in the wave climate (and 28 depending on the emission scenario) escalate the erosion/flooding risk by up to 300% over the 29 next 30 years. We also find significant changes in the seasonal cycles of sea level and 30 significant wave height, which have in combination caused a considerable increase of the 31 erosion/flooding risk in summer and decrease in winter (superimposed onto the long-term 32 trends)

The value of long-term silvicultural research studies

Treesearch

Wayne D. Shepperd; Carleton B. Edminster

1997-01-01

Reductions in research operating budgets and recent trends in research management philosophy have in many instances forced Forest Service scientists to realign their research programs to compete for short-term grants and other sources of funding. This approach may prove detrimental in silviculture, a discipline where long-term research is critical for: (1) research in...

Towards a Standard for Provenance and Context for Preservation of Data for Earth System Science

NASA Technical Reports Server (NTRS)

Ramaprian, Hampapuram K.; Moses, John F.

2011-01-01

Long-term data sets with data from many missions are needed to study trends and validate model results that are typical in Earth System Science research. Data and derived products originate from multiple missions (spaceborne, airborne and/or in situ) and from multiple organizations. During the missions as well as well past their termination, it is essential to preserve the data and products to support future studies. Key aspects of preservation are: preserving bits and ensuring data are uncorrupted, preserving understandability with appropriate documentation, and preserving reproducibility of science with appropriate documentation and other artifacts. Computer technology provides adequate standards to ensure that, with proper engineering, bits are preserved as hardware evolves. However, to ensure understandability and reproducibility, it is essential to plan ahead to preserve all the relevant data and information. There are currently no standards to identify the content that needs to be preserved, leading to non-uniformity in content and users not being sure of whether preserved content is comprehensive. Each project, program or agency can specify the items to be preserved as a part of its data management requirements. However, broader community consensus that cuts across organizational or national boundaries would be needed to ensure comprehensiveness, uniformity and long-term utility of archived data. The Federation of Earth Science Information Partners (ESIP), a diverse network of scientists, data stewards and technology developers, has a forum for ESIP members to collaborate on data preservation issues. During early 2011, members discussed the importance of developing a Provenance and Context Content Standard (PCCS) and developed an initial list of content items. This list is based on the outcome of a NASA and NOAA meeting held in 1998 under the auspices of the USGCRP, documentation requirements from NOAA and our experience with some of the NASA Earth science missions. The items are categorized into the following 8 high level categories: Preflight/Pre-Operations, Products (Data), Product Documentation, Mission Calibration, Product Software, Algorithm Input, Validation, Software Tools.

Reference Model for an Open Archival Information System

NASA Technical Reports Server (NTRS)

1997-01-01

This document is a technical report for use in developing a consensus on what is required to operate a permanent, or indefinite long-term, archive of digital information. It may be useful as a starting point for a similar document addressing the indefinite long-term preservation of non-digital information. This report establishes a common framework of terms and concepts which comprise an Open Archival Information System (OAIS). It allows existing and future archives to be more meaningfully compared and contrasted. It provides a basis for further standardization of within an archival context and it should promote greater vendor awareness of, and support of , archival requirements. Through the process of normal evolution, it is expected that expansion, deletion, or modification to this document may occur. This report is therefore subject to CCSDS document management and change control procedures.

Long-term Internal Variability of the Tropical Pacific Atmosphere-Ocean System

NASA Astrophysics Data System (ADS)

Hadi Bordbar, Mohammad; Martin, Thomas; Park, Wonsun; Latif, Mojib

2016-04-01

The tropical Pacific has featured some remarkable trends during the recent decades such as an unprecedented strengthening of the Trade Winds, a strong cooling of sea surface temperatures (SST) in the eastern and central part, thereby slowing global warming and strengthening the zonal SST gradient, and highly asymmetric sea level trends with an accelerated rise relative to the global average in the western and a drop in the eastern part. These trends have been linked to an anomalously strong Pacific Walker Circulation, the major zonal atmospheric overturning cell in the tropical Pacific sector, but the origin of the strengthening is controversial. Here we address the question as to whether the recent decadal trends in the tropical Pacific atmosphere-ocean system are within the range of internal variability, as simulated in long unforced integrations of global climate models. We show that the recent trends are still within the range of long-term internal decadal variability. Further, such variability strengthens in response to enhanced greenhouse gas concentrations, which may further hinder detection of anthropogenic climate signals in that region.

Student Enrollment Data and Trends in the Public Community Colleges of Illinois: Fall 1975, Second Term FY1976, and Fall 1976. Data and Characteristics Volume IV Number 1 [and] Volume V Number 2.

ERIC Educational Resources Information Center

Illinois Community Coll. Board, Springfield.

These documents contain narrative analyses and tables of data pertaining to student enrollment and enrollment trends in Illinois public community colleges for fall 1975, spring 1976, and fall 1976. Data presented in tabular form include: comparison and trends in enrollment data from 1965 through 1975, enrollment data for fall 1975 relating to…

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

Edgar, Thomas W.; Hadley, Mark D.; Manz, David O.

This document provides the methods to secure routable control system communication in the electric sector. The approach of this document yields a long-term vision for a future of secure communication, while also providing near term steps and a roadmap. The requirements for the future secure control system environment were spelled out to provide a final target. Additionally a survey and evaluation of current protocols was used to determine if any existing technology could achieve this goal. In the end a four-step path was described that brought about increasing requirement completion and culminates in the realization of the long term vision.

2010 Vehicle Technologies Market Report

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

Ward, Jacob; Davis, Stacy Cagle; Diegel, Susan W

2011-06-01

In the past five years, vehicle technologies have advanced on a number of fronts: power-train systems have become more energy efficient, materials have become more lightweight, fuels are burned more cleanly, and new hybrid electric systems reduce the need for traditional petroleum-fueled propulsion. This report documents the trends in market drivers, new vehicles, and component suppliers. This report is supported by the U.S. Department of Energy s (DOE s) Vehicle Technologies Program, which develops energy-efficient and environmentally friendly transportation technologies that will reduce use of petroleum in the United States. The long-term aim is to develop "leap frog" technologies thatmore » will provide Americans with greater freedom of mobility and energy security, while lowering costs and reducing impacts on the environment.« less

Comment and response document for the long-term surveillance plan for the Bodo Canyon Disposal Site, Durango, Colorado, Revision 0

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

NONE

1995-11-01

This report contains the comment and response document for the Draft Long-Term Surveillance Plan of the Bodo Canyon Site in Durango, California. This is a part of the Uranium Mill Tailings Remedial Action (UMTRA) Project. Questions and comments regarding specific sections or statements in the report are described and then a response to each review comment or question is provided.

Multi-decade Measurements of the Long-Term Trends of Atmospheric Species by High-Spectral-Resolution Infrared Solar Absorption Spectroscopy

NASA Technical Reports Server (NTRS)

Rinsland, Curtis P.; Chiou, Linda; Goldman, Aaron; Hannigan, James W.

2010-01-01

Solar absorption spectra were recorded for the first time in 5 years with the McMath Fourier transform spectrometer at the US National solar Observatory on Kitt Peak in southern Arizona, USA (31.91 N latitude, 111.61 W longitude, 2.09 km altitude). The solar absorption spectra cover 750-1300 and 1850-5000 cm(sup -1) and were recorded on 20 days during March-June 2009. The measurements mark the continuation of a long-term record of atmospheric chemical composition measurements that have been used to quantify seasonal cycles and long-term trends of both tropospheric and stratospheric species from observations that began i 1977. Fits to the measured spectra have been performed, and they indicate the spectra obtained since return to operational status are nearly free of channeling and the instrument line shape function is well reproduced taking into account the measurement parameters. We report updated time series measurements of total columns for six atmospheric species and their analysis for seasonal cycles and long-term trends. An sn example, the time series fit shows a decrease in the annual increase rate i Montreal-Protocol-regulated chlorofluorocarbon CCL2F2 from 1.51 plus or minus 0.38% yr(sup -1) at the beginning of the time span to -1.54 plus or minus 1.28 yr(sup -1) at the end of the time span, 1 sigma, and hence provides evidence for the impact of those regulations on the trend.

Long-Term Ethylene Oxide Exposure Trends in US Hospitals: Relationship With OSHA Regulatory and Enforcement Actions

PubMed Central

LaMontagne, Anthony D.; Oakes, J. Michael; Lopez Turley, Ruth N.

2004-01-01

Objectives. We assessed long-term trends in ethylene oxide (EtO) worker exposures for the purposes of exposure surveillance and evaluation of the impacts of the Occupational Safety and Health Administration (OSHA) 1984 and 1988 EtO standards. Methods. We obtained exposure data from a large commercial vendor and processor of EtO passive dosimeters. Personal samples (87 582 workshift [8-hr] and 46 097 short-term [15-min] samples) from 2265 US hospitals were analyzed for time trends from 1984 through 2001 and compared with OSHA enforcement data. Results. Exposures declined steadily for the first several years after the OSHA standards were set. Workshift exposures continued to taper off and have remained low and constant through 2001. However, since 1996, the probability of exceeding the short-term excursion limit has increased. This trend coincides with a decline in enforcement of the EtO standard. Conclusions. Results indicate the need for renewed intervention efforts to preserve gains made following the passage and implementation of the 1984 and 1988 EtO standards. PMID:15333324

Meridional displacement of the Antarctic Circumpolar Current

PubMed Central

Gille, Sarah T.

2014-01-01

Observed long-term warming trends in the Southern Ocean have been interpreted as a sign of increased poleward eddy heat transport or of a poleward displacement of the entire Antarctic Circumpolar Current (ACC) frontal system. The two-decade-long record from satellite altimetry is an important source of information for evaluating the mechanisms governing these trends. While several recent studies have used sea surface height contours to index ACC frontal displacements, here altimeter data are instead used to track the latitude of mean ACC transport. Altimetric height contours indicate a poleward trend, regardless of whether they are associated with ACC fronts. The zonally averaged transport latitude index shows no long-term trend, implying that ACC meridional shifts determined from sea surface height might be associated with large-scale changes in sea surface height more than with localized shifts in frontal positions. The transport latitude index is weakly sensitive to the Southern Annular Mode, but is uncorrelated with El Niño/Southern Oscillation. PMID:24891396

Population trends of forest birds at Hakalau Forest National Wildlife Refuge, Hawai'i

USGS Publications Warehouse

Camp, Richard J.; Pratt, Thane K.; Gorresen, P. Marcos; Jeffrey, John J.; Woodworth, Bethany L.

2010-01-01

The Hakalau Forest National Wildlife Refuge was established to protect native Hawaiian forest birds, particularly endangered species. Management for forest restoration on the refuge has consisted mainly of removing feral ungulates, controlling invasive alien plants, and reforesting former pastures. To assess effects of this habitat improvement for forest birds, we estimated density annually by distance sampling and examined population trends for native and alien passerines over the 21 years since the refuge was established. We examined long-term trends and recent short-term trajectories in three study areas: (1) reforested pastureland, (2) heavily grazed open forest that was recovering, and (3) lightly grazed closed forest that was relatively intact. Three species of native birds and two species of alien birds had colonized the reforested pasture and were increasing. In the open forest, densities of all eight native species were either stable or increasing. Long-term trends for alien birds were also generally stable or increasing. Worryingly, however, during the most recent 9 years, in the open forest trajectories of native species were decreasing or inconclusive, but in the reforested pasture they generally increased. The closed forest was surveyed in only the most recent 9 years, and trajectories of native species there were mixed. Overall, long-term population trends in Hakalau are stable or increasing, contrasting with declines in most other areas of Hawai'i over the same period. However, more recent mixed results may indicate emergent problems for this important bird area.

A search for scale in sea-level studies

USGS Publications Warehouse

Larsen, C.E.; Clark, I.

2006-01-01

Many researchers assume a proportional relationship among the atmospheric CO2 concentration, temperature, and sea level. Thus, the rate of sea-level rise should increase in concert with the documented exponential increase in CO2. Although sea surface temperature has increased in places over the past century and short-term sea level rose abruptly during the 1990s, it is difficult to demonstrate a proportional relationship using existing geologic or historic records. Tide gauge records in the United States cover too short a time interval to verify acceleration in the rate of sea-level rise, although multicentury tide gauge and staff records from the Netherlands and Sweden suggest a mid-19th-century acceleration in sea-level rise. Reconstructions of sea-level changes for the past 1000 years derived using benthic foraminifer data from salt marshes along the East Coast of the United States suggest an increased rate of relative sea-level rise beginning in the 1600s. Geologic records of relative sea-level rise for the past 6000 years are available for several sites along the US East Coast from 14C-dated basal peat below salt marshes and estuarine sediments. When these three scales of sea-level variation are integrated, adjusted for postglacial isostatic movement, and replotted, the range of variation in sea level suggested by basal peat ages is within ??1 meter of the long-term trend. The reconstruction from Long Island Sound data shows a linear rise in sea level beginning in the mid-1600s at a rate consistent with the historic record of mean high water. Long-term tide gauge records from Europe and North America show similar trends since the mid-19th century. There is no clear proportional exponential increase in the rate of sea-level rise. If proportionality exists among sea level, atmospheric CO2, and temperature, there may be a significant time lag before an anthropogenic increase in the rate of sea-level rise occurs.

Modeling the Thickness of Perennial Ice Covers on Stratified Lakes of the Taylor Valley, Antarctica

NASA Technical Reports Server (NTRS)

Obryk, M. K.; Doran, P. T.; Hicks, J. A.; McKay, C. P.; Priscu, J. C.

2016-01-01

A one-dimensional ice cover model was developed to predict and constrain drivers of long term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 years (between 1996 and 2012) of ice thickness changes for west lobe of Lake Bonney (average ice thickness = 3.53 m; RMSE = 0.09 m, n = 118) and Lake Fryxell (average ice thickness = 4.22 m; RMSE = 0.21 m, n = 128). Long-term ice thickness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of lakes exceeding a liquid water column depth of 20 m can either impede or facilitate ice thickness change depending on the predominant climatic trend (temperature cooling or warming). As such, shallow (< 20 m deep water columns) perennially ice-covered lakes without deep temperature maxima are more sensitive indicators of climate change. The long-term ice thickness trends are a result of surface energy flux and heat flux from the deep temperature maximum in the water column, the latter of which results from absorbed solar radiation.

Exploring African Aridification and Wet/dry Cycles Over the Last 3 MA

NASA Astrophysics Data System (ADS)

Meyers, C.; Tierney, J. E.; DeMenocal, P. B.

2011-12-01

Marine sediment records document a gradual increase in aeolian dust supply from Africa over the last 3 Ma in the Atlantic, Gulf of Aden, and Mediterranean (Larrasoaña et al., 2003, deMenocal 2004), with 'steps' in period and amplitude at ~2.8 Ma, ~1.7 Ma, and ~1.0 Ma. However, Mediterranean sapropel sequences document regular, precession-paced wet/dry cycles from changes in the strength of the African monsoon and Nile runoff since at least the Miocene (Rossignol-Strick, 1985, Krijgsman et al., 1995, Lourens et al., 1996). The influence of long-term drying trends in Africa on the movements and strength of the African monsoon over the late Pliocene and Pleistocene is not understood. We have constructed a biomarker-based African climate record by analyzing concentrations and δ D from long-chain, saturated fatty acid methyl esters (FAMEs) in eastern Mediterranean ODP Site 967 sediments from 2.8 - 3.1 Ma and 1.6 - 1.8 Ma. Long-chain fatty acids are produced in the leaf waxes of terrestrial plants (Eglinton and Hamilton, 1967) and are transported to marine sediments via aeolian and fluvial action. Sapropel sediments corresponding with precession minima and enhanced Nile River runoff (Rossignol-Strick, 1985) contain much higher concentrations of FAMEs than carbonate-rich sediments. Comparisons of the two intervals will be presented to illustrate changes in monsoon strength from 3 Ma to 1.6 Ma.

Generating Vegetation Leaf Area Index Earth System Data Record from Multiple Sensors. Part 2; Implementation, Analysis and Validation

NASA Technical Reports Server (NTRS)

Ganguly, Sangram; Samanta, Arindam; Schull, Mitchell A.; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramajrushna R,; Knyazikhin, Yuri; Myneni, Ranga B.

2008-01-01

The evaluation of a new global monthly leaf area index (LAI) data set for the period July 1981 to December 2006 derived from AVHRR Normalized Difference Vegetation Index (NDVI) data is described. The physically based algorithm is detailed in the first of the two part series. Here, the implementation, production and evaluation of the data set are described. The data set is evaluated both by direct comparisons to ground data and indirectly through inter-comparisons with similar data sets. This indirect validation showed satisfactory agreement with existing LAI products, importantly MODIS, at a range of spatial scales, and significant correlations with key climate variables in areas where temperature and precipitation limit plant growth. The data set successfully reproduced well-documented spatio-temporal trends and inter-annual variations in vegetation activity in the northern latitudes and semi-arid tropics. Comparison with plot scale field measurements over homogeneous vegetation patches indicated a 7% underestimation when all major vegetation types are taken into account. The error in mean values obtained from distributions of AVHRR LAI and high-resolution field LAI maps for different biomes is within 0.5 LAI for six out of the ten selected sites. These validation exercises though limited by the amount of field data, and thus less than comprehensive, indicated satisfactory agreement between the LAI product and field measurements. Overall, the intercomparison with short-term LAI data sets, evaluation of long term trends with known variations in climate variables, and validation with field measurements together build confidence in the utility of this new 26 year LAI record for long term vegetation monitoring and modeling studies.

A Blueprint for the Ecological Monitoring of Australia's Oceans.

NASA Astrophysics Data System (ADS)

Bax, N. J.; Hayes, K. R.; Dambacher, J. M.; Hosack, G. R.; Dunstan, P. K.; Fulton, E.; Thompson, P. A.; Hartog, J. R.; Hobday, A. J.; Bradford, R.; Foster, S.; Hedge, P.; Smith, D.; Marshall, C. M.

2016-02-01

Monitoring Australia's marine area is fundamental to understanding and documenting how the ocean is changing in response to human pressures. Fifty-four key ecological features (KEFs) were identified as areas of particular value to the Australian Government over the last 8 years. These were divided into six reporting groups: areas of enhanced pelagic productivity, canyons, deep seabeds, seamounts, shelf reefs and seabeds. Ecosystem models were built for 33 KEF systems that have the strongest datasets, based on a theoretical understanding of how they function. Human pressures were identified by regional specialists and combined with the KEF models to create a set of medium-term pressure scenarios for each KEF. Between four and 25 pressure scenarios were identified for each KEF. Examples of human pressures include the strengthening of the East Australian Current and shifts in ocean upwelling due to climate change, major fluctuations in pelagic fish and fur seal populations, and fishing, shipping and oil and gas activities. KEF models encompass parts of the ecosystem that have potential to be monitored as long-term indicators that increase, decrease, or remain unchanged under each pressure scenario. Suitable indicators are those that respond in predictable ways across all pressure scenarios for a KEF. Results from pressure scenarios developed to test indicators for Australia's nine enhanced pelagic productivity KEFs will be presented. Satellite observations were analysed to tease out the long-term trend in phytoplankton and ocean upwelling. The comparison of predicted and observed trends in indicators leads to an improved understanding of KEF systems and the utility of the indicators. A change in indicator is a signal that something was happening to a valued system. The prediction-observation process would explain why. This process is repeatable and can be updated as new information comes available.

Long-term effect of fee-for-service-based reimbursement cuts on processes and outcomes of care for stroke: interrupted time-series study from Taiwan.

PubMed

Tung, Yu-Chi; Chang, Guann-Ming; Cheng, Shou-Hsia

2015-01-01

As healthcare spending continues to increase, reimbursement cuts have become 1 type of healthcare reform to contain costs. Little is known about the long-term impact of cuts in reimbursement, especially under a global budget cap with fee-for-service (FFS) reimbursement, on processes and outcomes of care. The FFS-based reimbursement cuts have been implemented since July 2002 in Taiwan. We examined the long-term association of FFS-based reimbursement cuts with trends in processes and outcomes of care for stroke. We analyzed all 411,487 patients with stroke admitted to general acute care hospitals in Taiwan during the period 1997 to 2010 through Taiwan's National Health Insurance Research Database. We used a quasi-experimental design with quarterly measures of healthcare utilization and outcomes and used segmented autoregressive integrated moving average models for the analysis. After accounting for secular trends and other confounders, the implementation of the FFS-based reimbursement cuts was associated with trend changes in computed tomography/magnetic resonance imaging scanning (0.31% per quarter; P=0.013), antiplatelet/anticoagulant use (-0.20% per quarter; P<0.001), statin use (0.18% per quarter; P=0.027), physiotherapy/occupational therapy assessment (0.25% per quarter; P<0.001), and 30-day mortality (0.06% per quarter; P<0.001). There are improvement trends in processes and outcomes of care over time. However, the reimbursement cuts from the FFS-based global budget cap are associated with trend changes in processes and outcomes of care for stroke. The FFS-based reimbursement cuts may have long-term positive and negative associations with stroke care. © 2014 American Heart Association, Inc.

A power analysis for multivariate tests of temporal trend in species composition.

PubMed

Irvine, Kathryn M; Dinger, Eric C; Sarr, Daniel

2011-10-01

Long-term monitoring programs emphasize power analysis as a tool to determine the sampling effort necessary to effectively document ecologically significant changes in ecosystems. Programs that monitor entire multispecies assemblages require a method for determining the power of multivariate statistical models to detect trend. We provide a method to simulate presence-absence species assemblage data that are consistent with increasing or decreasing directional change in species composition within multiple sites. This step is the foundation for using Monte Carlo methods to approximate the power of any multivariate method for detecting temporal trends. We focus on comparing the power of the Mantel test, permutational multivariate analysis of variance, and constrained analysis of principal coordinates. We find that the power of the various methods we investigate is sensitive to the number of species in the community, univariate species patterns, and the number of sites sampled over time. For increasing directional change scenarios, constrained analysis of principal coordinates was as or more powerful than permutational multivariate analysis of variance, the Mantel test was the least powerful. However, in our investigation of decreasing directional change, the Mantel test was typically as or more powerful than the other models.

Site productivity and diversity of the Middle Mountain long-term soil productivity study, West Virginia: Pre-experimental site characterization

Treesearch

Mary Beth Adams

2018-01-01

To better understand the impacts of a changing environment and interactions with forest management options for forest resources, including soil, large long-term experiments are required. Such experiments require careful documentation of reference or pre-experimental conditions. This publication describes the Middle Mountain Long-term Soil Productivity (LTSP) Study,...

Long term pavement performance program protocol for calibrating traffic data collection equipment

DOT National Transportation Integrated Search

1998-05-10

This document describes the procedures that the Long Term Pavement Performance (LTPP) program recommends for ensuring that traffic data collection equipment used for LTPP traffic monitoring efforts operates correctly and collects valid data.

GATEWAY Demonstrations: Long-Term Evaluation of SSL Field Performance in Select Interior Projects

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

Davis, Tess E.; Davis, Robert G.; Wilkerson, Andrea M.

The GATEWAY program evaluated the long-term performance characteristics (chromaticity change, maintained illuminance, and operations and maintenance) of LED lighting systems in four field installations previously documented in separate DOE GATEWAY reports.

The long-term physical and psychological health impacts of flooding: A systematic mapping.

PubMed

Zhong, Shuang; Yang, Lianping; Toloo, Sam; Wang, Zhe; Tong, Shilu; Sun, Xiaojie; Crompton, David; FitzGerald, Gerard; Huang, Cunrui

2018-06-01

Flooding has caused significant and wide ranging long-term health impacts for affected populations. However, until now, the long-term health outcomes, epidemiological trends and specific impact factors of flooding had not been identified. In this study, the relevant literature was systematically mapped to create the first synthesis of the evidence of the long-term health impacts of flooding. The systematic mapping method was used to collect and categorize all the relevant literature. A study was included if it had a description or measurement of health impacts over six months after flooding. The search was limited to peer reviewed articles and grey literature written in English, published from 1996 to 2016. A total of 56 critical articles were extracted for the final map, including 5 qualitative and 51 quantitative studies. Most long-term studies investigated the psychological impacts of flooding, including PTSD, depression, anxiety, psychiatric disorders, sleep disorder and suicide. Others investigated the physiological impacts, including health-related quality of life, acute myocardial infarction, chronic diseases, and malnutrition. Social support was proved to be protective factors that can improve health outcomes in the long-term after flooding. To date, there have been relatively few reviews had focused on the long-term health impacts of flooding. This study coded and catalogued the existing evidence across a wide range of variables and described the long-term health consequences within a conceptual map. Although there was no boundary between the short-term and the long-term impacts of flooding, the identified health outcomes in this systematic mapping could be used to define long-term health impacts. The studies showed that the prevalence of psychological diseases had a reversed increasing trend occurred even in the long-term in relatively poor post-flooding environments. Further cohort or longitudinal research focused on disability, chronic diseases, relocation population, and social interventions after flooding, are urgently required. Copyright © 2018 Elsevier B.V. All rights reserved.

Evidence based medicine and surgical approaches for colon cancer: evidences, benefits and limitations of the laparoscopic vs open resection.

PubMed

Lorenzon, Laura; La Torre, Marco; Ziparo, Vincenzo; Montebelli, Francesco; Mercantini, Paolo; Balducci, Genoveffa; Ferri, Mario

2014-04-07

To report a meta-analysis of the studies that compared the laparoscopic with the open approach for colon cancer resection. Forty-seven manuscripts were reviewed, 33 of which employed for meta-analysis according to the PRISMA guidelines. The results were differentiated according to the study design (prospective randomized trials vs case-control series) and according to the tumor's location. Outcome measures included: (1) short-term results (operating times, blood losses, bowel function recovery, post-operative pain, return to the oral intake, complications and hospital stay); (2) oncological adequateness (number of nodes harvested in the surgical specimens); and (3) long-term results (including the survivals' rates and incidence of incisional hernias) and (4) costs. Meta-analysis of trials provided evidences in support of the laparoscopic procedures for a several short-term outcomes including: a lower blood loss, an earlier recovery of the bowel function, an earlier return to the oral intake, a shorter hospital stay and a lower morbidity rate. Opposite the operating time has been confirmed shorter in open surgery. The same trend has been reported investigating case-control series and cancer by sites, even though there are some concerns regarding the power of the studies in this latter field due to the small number of trials and the small sample of patients enrolled. The two approaches were comparable regarding the mean number of nodes harvested and long-term results, even though these variables were documented reviewing the literature but were not computable for meta-analysis. The analysis of the costs documented lower costs for the open surgery, however just few studies investigated the incidence of post-operative hernias. Laparoscopy is superior for the majority of short-term results. Future studies should better differentiate these approaches on the basis of tumors' location and the post-operative hernias.

National assessment of shoreline change: historical change along the north coast of Alaska, U.S.-Canadian border to Icy Cape

USGS Publications Warehouse

Gibbs, Ann E.; Richmond, Bruce M.

2015-01-01

Similar to the earlier reports in this series, this report summarizes the methods of analysis, documents and describes the results of the analysis, and explains historical trends and rates of shoreline change. This Alaska shoreline change assessment differs from previously published shoreline change assessments in that: (1) only two historical shorelines (from the 1940s and 2000s eras) were available for the Alaska study area whereas four or more shorelines (from 1850 to 2002) were available for the other assessments and, thus, only end-point rates for one long-term analysis period are reported here, compared to a combination of long-term and short-term rates as reported in other studies; (2) modern (2000s era) shorelines in this study represent a visually derived land-water interface position versus an elevation based, tidally referenced shoreline position; and (3) both exposed open-ocean and sheltered mainland-lagoon shorelines and rates of change are included in this study compared to other locations where only exposed open-ocean sandy shorelines or bluff edges were evaluated. No distinction was made between sand or gravel beaches, and the base of the unconsolidated coastal bluff was considered the shoreline where no fronting beach existed.

AR(p) -based detrended fluctuation analysis

NASA Astrophysics Data System (ADS)

Alvarez-Ramirez, J.; Rodriguez, E.

2018-07-01

Autoregressive models are commonly used for modeling time-series from nature, economics and finance. This work explored simple autoregressive AR(p) models to remove long-term trends in detrended fluctuation analysis (DFA). Crude oil prices and bitcoin exchange rate were considered, with the former corresponding to a mature market and the latter to an emergent market. Results showed that AR(p) -based DFA performs similar to traditional DFA. However, the former DFA provides information on stability of long-term trends, which is valuable for understanding and quantifying the dynamics of complex time series from financial systems.

Factors affecting long-term trends in surface-water quality in the Gwynns Falls watershed, Baltimore City and County, Maryland, 1998–2016

USGS Publications Warehouse

Majcher, Emily H.; Woytowitz, Ellen L.; Reisinger, Alexander J.; Groffman, Peter M.

2018-03-30

Factors affecting water-quality trends in urban streams are not well understood, despite current regulatory requirements and considerable ongoing investments in gray and green infrastructure. To address this gap, long-term water-quality trends and factors affecting these trends were examined in the Gwynns Falls, Maryland, watershed during 1998–2016 in cooperation with Blue Water Baltimore. Data on water-quality constituents and potential factors of influence were obtained from multiple sources and compiled for analysis, with a focus on data collected as part of the National Science Foundation funded Long-Term Ecological Research project, the Baltimore Ecosystem Study.Variability in climate (specifically, precipitation) and land cover can overwhelm actions taken to improve water quality and can present challenges for meeting regulatory goals. Analysis of land cover during 2001–11 in the Gwynns Falls watershed indicated minimal change during the study time frame; therefore, land-cover change is likely not a factor affecting trends in water quality. However, a modest increase in annual precipitation and a significant increase in winter precipitation were apparent in the region. A higher proportion of runoff producing storms was observed in the winter and a lower proportion in the summer, indicating that climate change may affect water quality in the watershed. The increase in precipitation was not reflected in annual or seasonal trends of streamflow in the watershed. Nonetheless, these precipitation changes may exacerbate the inflow and infiltration of water to gray infrastructure and reduce the effectiveness of green infrastructure. For streamflow and most water-quality constituents examined, no discernable trends were noted over the timeframe examined. Despite the increases in precipitation, no trends were observed for annual or seasonal discharge at the various sites within the study area. In some locations, nitrate, phosphate, and total nitrogen show downward trends, and total phosphorus and chloride show upward trends.Sanitary sewer overflows (gray infrastructure) and best management practices (green infrastructure) were identified as factors affecting water-quality change. The duration of sanitary sewer overflows was positively correlated with annual loads of nutrients and bacteria, and the drainage area of best management practices was negatively correlated with annual loads of phosphate and sulfate. Results of the study indicate that continued investments in gray and green infrastructure are necessary for urban water-quality improvement. Although this outcome is not unexpected, long-term datasets such as the one used in this study, allow the effects of gray and green infrastructures to be quantified.Results of this study have implications for the Gwynns Falls watershed and its residents and Baltimore City and County managers. Moreover, outcomes are relevant to other watersheds in the metropolitan region that do not have the same long-term dataset. Further, this study has established a framework for ongoing statistical analysis of primary factors affecting urban water-quality trends as regulatory programs mature.

California travel trends and demographics study

DOT National Transportation Integrated Search

2002-12-01

In collaboration with its regional and citizen planning partners, the California Department of Transportation is currently developing a long-term, multimodal transportation plan for the state of California. The California Travel Trends and Demographi...

Historical trends and high-resolution future climate projections in northern Tuscany (Italy)

NASA Astrophysics Data System (ADS)

D'Oria, Marco; Ferraresi, Massimo; Tanda, Maria Giovanna

2017-12-01

This paper analyzes the historical precipitation and temperature trends and the future climate projections with reference to the northern part of Tuscany (Italy). The trends are identified and quantified at monthly and annual scale at gauging stations with data collected for long periods (60-90 years). An ensemble of 13 Regional Climate Models (RCMs), based on two Representative Concentration Pathways (RCP4.5 and RCP8.5), was then used to assess local scale future precipitation and temperature projections and to represent the uncertainty in the results. The historical data highlight a general decrease of the annual rainfall at a mean rate of 22 mm per decade but, in many cases, the tendencies are not statistically significant. Conversely, the annual mean temperature exhibits an upward trend, statistically significant in the majority of cases, with a warming rate of about 0.1 °C per decade. With reference to the model projections and the annual precipitation, the results are not concordant; the deviations between models in the same period are higher than the future changes at medium- (2031-2040) and long-term (2051-2060) and highlight that the model uncertainty and variability is high. According to the climate model projections, the warming of the study area is unequivocal; a mean positive increment of 0.8 °C at medium-term and 1.1 °C at long-term is expected with respect to the reference period (2003-2012) and the scenario RCP4.5; the increments grow to 0.9 °C and 1.9 °C for the RCP8.5. Finally, in order to check the observed climate change signals, the climate model projections were compared with the trends based on the historical data. A satisfactory agreement is obtained with reference to the precipitation; a systematic underestimation of the trend values with respect to the models, at medium- and long-term, is observed for the temperature data.

Streamflow characteristics and trends along Soldier Creek, Northeast Kansas

USGS Publications Warehouse

Juracek, Kyle E.

2017-08-16

Historical data for six selected U.S. Geological Survey streamgages along Soldier Creek in northeast Kansas were used in an assessment of streamflow characteristics and trends. This information is required by the Prairie Band Potawatomi Nation for the effective management of tribal water resources, including drought contingency planning. Streamflow data for the period of record at each streamgage were used to assess annual mean streamflow, annual mean base flow, mean monthly flow, annual peak flow, and annual minimum flow.Annual mean streamflows along Soldier Creek were characterized by substantial year-to-year variability with no pronounced long-term trends. On average, annual mean base flow accounted for about 20 percent of annual mean streamflow. Mean monthly flows followed a general seasonal pattern that included peak values in spring and low values in winter. Annual peak flows, which were characterized by considerable year-to-year variability, were most likely to occur in May and June and least likely to occur during November through February. With the exception of a weak yet statistically significant increasing trend at the Soldier Creek near Topeka, Kansas, streamgage, there were no pronounced long-term trends in annual peak flows. Annual 1-day, 30-day, and 90-day mean minimum flows were characterized by considerable year-to-year variability with no pronounced long-term trend. During an extreme drought, as was the case in the mid-1950s, there may be zero flow in Soldier Creek continuously for a period of one to several months.

Climate Change and Political Instability in Syria

NASA Astrophysics Data System (ADS)

Kelley, C. P.; Mohtadi, S.; Cane, M. A.; Seager, R.; Kushnir, Y.

2013-12-01

From 2005 to 2010, Syria experienced the most severe and persistent drought in the instrumental record, devastating the agriculture and causing widespread crop failure. A mass migration of farming families to urban peripheries followed the resulting food shortages, unemployment, and disruption of rural social structure. The addition of nearly 1.5 million drought refugees to the recent influx of Iraqi refugees greatly exacerbated conditions in the urban slums. Anger at the government's failure to respond to the drought's impacts contributed to the political unrest that began in March 2011. The recent decrease in Syrian precipitation is a combination of natural variability and long-term drying trend, and the unusual severity of the observed drought is here shown to be highly unlikely without the trend. Precipitation changes in Syria are linked to rising mean sea-level pressure in the Eastern Mediterranean, which also shows a long-term trend. Compared to the natural variability alone, the trend has made the occurrence of such a severe drought eight times more likely. There has been also a long-term warming trend in Syria, adding to the drawdown of soil moisture. No natural cause is apparent for these trends, whereas the observed drying and warming are consistent with observed increases in greenhouse gases. Furthermore, model studies show an increasingly drier and hotter future mean climate for the Eastern Mediterranean. The severity and duration of the recent Syrian drought, implicated as a cause of the current conflict, is highly likely to be a consequence of human interference in the climate system.

Rapid warming of the world's lakes: Interdecadal variability and long-term trends from 1910-2009 using in situ and remotely sensed data

NASA Astrophysics Data System (ADS)

Lenters, J. D.; Read, J. S.; Sharma, S.; O'Reilly, C.; Hampton, S. E.; Gray, D.; McIntyre, P. B.; Hook, S. J.; Schneider, P.; Soylu, M. E.; Barabás, N.; Lofton, D. D.

2014-12-01

Global and regional changes in climate have important implications for terrestrial and aquatic ecosystems. Recent studies, for example, have revealed significant warming of inland water bodies throughout the world. To better understand the global patterns, physical mechanisms, and ecological implications of lake warming, an initiative known as the "Global Lake Temperature Collaboration" (GLTC) was started in 2010, with the objective of compiling and analyzing lake temperature data from numerous satellite and in situ records dating back at least 20-30 years. The GLTC project has now assembled data from over 300 lakes, with some in situ records extending back more than 100 years. Here, we present an analysis of the long-term warming trends, interdecadal variability, and a direct comparison between in situ and remotely sensed lake surface temperature for the 3-month summer period July-September (January-March for some lakes). The overall results show consistent, long-term trends of increasing summer-mean lake surface temperature across most but not all sites. Lakes with especially long records show accelerated warming in the most recent two to three decades, with almost half of the lakes warming at rates in excess of 0.5 °C per decade during the period 1985-2009, and a few even exceeding 1.0 °C per decade. Both satellite and in situ data show a similar distribution of warming trends, and a direct comparison at lake sites that have both types of data reveals a close correspondence in mean summer water temperature, interannual variability, and long-term trends. Finally, we examine standardized lake surface temperature anomalies across the full 100-year period (1910-2009), and in conjunction with similar timeseries of air temperature. The results reveal a close correspondence between summer air temperature and lake surface temperature on interannual and interdecadal timescales, but with many lakes warming more rapidly than the ambient air temperature over 25- to 100-year periods.

Identifying trends in climate: an application to the cenozoic

NASA Astrophysics Data System (ADS)

Richards, Gordon R.

1998-05-01

The recent literature on trending in climate has raised several issues, whether trends should be modeled as deterministic or stochastic, whether trends are nonlinear, and the relative merits of statistical models versus models based on physics. This article models trending since the late Cretaceous. This 68 million-year interval is selected because the reliability of tests for trending is critically dependent on the length of time spanned by the data. Two main hypotheses are tested, that the trend has been caused primarily by CO2 forcing, and that it reflects a variety of forcing factors which can be approximated by statistical methods. The CO2 data is obtained from model simulations. Several widely-used statistical models are found to be inadequate. ARIMA methods parameterize too much of the short-term variation, and do not identify low frequency movements. Further, the unit root in the ARIMA process does not predict the long-term path of temperature. Spectral methods also have little ability to predict temperature at long horizons. Instead, the statistical trend is estimated using a nonlinear smoothing filter. Both of these paradigms make it possible to model climate as a cointegrated process, in which temperature can wander quite far from the trend path in the intermediate term, but converges back over longer horizons. Comparing the forecasting properties of the two trend models demonstrates that the optimal forecasting model includes CO2 forcing and a parametric representation of the nonlinear variability in climate.

Using natural archives to track sources and long-term trends of pollution: an introduction

USGS Publications Warehouse

Jules Blais,; Rosen, Michael R.; John Smol,

2015-01-01

This book explores the myriad ways that environmental archives can be used to study the distribution and long-term trajectories of contaminants. The volume first focuses on reviews that examine the integrity of the historic record, including factors related to hydrology, post-depositional diffusion, and mixing processes. This is followed by a series of chapters dealing with the diverse archives available for long-term studies of environmental pollution.

Remotely-sensed sea surface temperatuares (SST) of Northeaster Pacific Coastal Zones

EPA Science Inventory

Sea surface temperature (SST) is an important indicator of long-term trends and geographical temperature patterns; however there have been relatively few long-term records of SST in near-coastal habitats. In situ SST measurements are irregular in both space and time. Therefore, w...

PERMEABLE REACTIVE BARRIER PERFORMANCE MONITORING: LONG-TERM TRENDS IN GEOCHEMICAL PARAMETERS AT TWO SITES

EPA Science Inventory

A major goal of research on the long-term performance of subsurface reactive barriers is to identify standard ground water monitoring parameters that may be useful indicators of declining performance or impending system failure. Results are presented from ground water monitoring ...

PERMEABLE REACTIVE BARRIER PERFORMANCE MONITORING: LONG-TERM TRENDS IN GEOCHEMICAL PARAMETERS AT TWO SITES

EPA Science Inventory

A major goal of research on the long-term performance of subsurface reactive barriers is to identify standard ground-water monitoring parameters that may be useful indicators of declining performance or impending system failure. Results are presented from studies conducted over ...

Long-term hydrometeorological trends in the Midwest region based on a century long gridded hydrometeorological dataset and simulations from a macro-scale hydrology model

NASA Astrophysics Data System (ADS)

Chiu, C. M.; Hamlet, A. F.

2014-12-01

Climate change is likely to impact the Great Lakes region and Midwest region via changes in Great Lakes water levels, agricultural impacts, river flooding, urban stormwater impacts, drought, water temperature, and impacts to terrestrial and aquatic ecosystems. Self-consistent and temporally homogeneous long-term data sets of precipitation and temperature over the entire Great Lakes region and Midwest regions are needed to provide inputs to hydrologic models, assess historical trends in hydroclimatic variables, and downscale global and regional-scale climate models. To support these needs a new hybrid gridded meteorological forcing dataset at 1/16 degree resolution based on data from co-op station records, the U. S Historical Climatology Network (HCN) , the Historical Canadian Climate Database (HCCD), and Precipitation Regression on Independent Slopes Method (PRISM) has been assembled over the Great Lakes and Midwest region from 1915-2012 at daily time step. These data were then used as inputs to the macro-scale Variable Infiltration Capacity (VIC) hydrology model, implemented over the Midwest and Great Lakes region at 1/16 degree resolution, to produce simulated hydrologic variables that are amenable to long-term trend analysis. Trends in precipitation and temperature from the new meteorological driving data sets, as well as simulated hydrometeorological variables such as snowpack, soil moisture, runoff, and evaporation over the 20th century are presented and discussed.

Subsurface Remediation: Improving Long-Term Monitoring and Remedial Systems Performance Conference Proceedings

EPA Pesticide Factsheets

This document summarizes the presentations and workshops of a conference on improving long-term monitoring (LTM) and remedial systems performance that was held in St. Louis, Missouri between June 8th to 11th, 1999.

Elevation-dependent temperature trends in the Rocky Mountain Front Range: changes over a 56- and 20-year record.

PubMed

McGuire, Chris R; Nufio, César R; Bowers, M Deane; Guralnick, Robert P

2012-01-01

Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953-2008) and a shorter 20-year (1989-2008) record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM) datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data, we caution against an over-reliance on interpolation methods for documenting local patterns of climatic change.

Elevation-Dependent Temperature Trends in the Rocky Mountain Front Range: Changes over a 56- and 20-Year Record

PubMed Central

McGuire, Chris R.; Nufio, César R.; Bowers, M. Deane; Guralnick, Robert P.

2012-01-01

Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953–2008) and a shorter 20-year (1989–2008) record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM) datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data, we caution against an over-reliance on interpolation methods for documenting local patterns of climatic change. PMID:22970205

Multi-Scale Analysis of Trends in Northeastern Temperate Forest Springtime Phenology

NASA Astrophysics Data System (ADS)

Moon, M.; Melaas, E. K.; Sulla-menashe, D. J.; Friedl, M. A.

2017-12-01

The timing of spring leaf emergence is highly variable in many ecosystems, exerts first-order control growing season length, and significantly modulates seasonally-integrated photosynthesis. Numerous studies have reported trends toward earlier spring phenology in temperate forests, with some papers indicating that this trend is also leading to increased carbon uptake. At broad spatial scales, however, most of these studies have used data from coarse spatial resolution instruments such as MODIS, which does not resolve ecologically important landscape-scale patterns in phenology. In this work, we examine how long-term trends in spring phenology differ across three data sources acquired at different scales of measurements at the Harvard Forest in central Massachusetts. Specifically, we compared trends in the timing of phenology based on long-term in-situ measurements of phenology, estimates based on eddy-covariance measurements of net carbon uptake transition dates, and from two sources of satellite-based remote sensing (MODIS and Landsat) land surface phenology (LSP) data. Our analysis focused on the flux footprint surrounding the Harvard Forest Environmental Measurements (EMS) tower. Our results reveal clearly defined trends toward earlier springtime phenology in Landsat LSP and in the timing of tower-based net carbon uptake. However, we find no statistically significant trend in springtime phenology measured from MODIS LSP data products, possibly because the time series of MODIS observations is relatively short (13 years). The trend in tower-based transition data exhibited a larger negative value than the trend derived from Landsat LSP data (-0.42 and -0.28 days per year for 21 and 28 years, respectively). More importantly, these results have two key implications regarding how changes in spring phenology are impacting carbon uptake at landscape-scale. First, long-term trends in spring phenology can be quite different, depending on what data source is used to estimate the trend, and 2) the response of carbon uptake to climate change may be more sensitive than the response of land surface phenology itself.

Long-term growth trends and time series of elemental wood composition from two old-growth forests - natural versus anthropogenic influences

NASA Astrophysics Data System (ADS)

Scharnweber, Tobias; van der Maaten, Ernst; Heinrich, Ingo; Buras, Allan; van der Maaten Theunissen, Marieke; Wilmking, Martin

2014-05-01

In contrast to extreme environments with low human impact, where often one specific (climatic) factor is limiting tree growth, dendrochronological research in the temperate zone has to cope with a wide variety of climatic and non-climatic drivers. Sophisticated statistical tools, like various detrending and filtering techniques, allow for a rather precise analysis of high-frequency (annual) climate-growth relationships. However, as almost all forests in the temperate zone are to some degree influenced by human activities, it is difficult to separate anthropogenic from climatic influence on the lower time-frequencies of decades to centuries. Footprints of human activity in time series of tree-ring parameters might be caused directly through forest utilization (logging) or indirectly through environmental changes such as eutrophication or atmospheric pollution. The former can be elucidated by traditional dendrochronological techniques based on ring parameters; evaluation of the latter requires additional proxies such as dendrochemical data. For the interpretation of long-term trends and the calibration of tree-ring based reconstructions it is therefore necessary to study tree growth in as undisturbed forest environments as possible. Comparison with dendrochronological time series from managed forest might then allow separation of climatic- from anthropogenic signals. Here, we present long-term growth trends for the broadleaved tree species common beech, pedunculate oak and sycamore maple, from two protected old-growth forests in northern Germany (one with a documented last logging activity dating back to 1527), and compare those with well-replicated regional chronologies from other, mostly managed forests. Our results indicate that several low frequency trends that can be found in many regional chronologies are likely caused by synchronous periods of heavy loggings as for example during the years following World War II, and do not relate to climatic drivers. In addition, elemental wood composition of trees growing on an island relatively isolated from agricultural depositions or direct atmospheric pollution is compared to elemental concentrations in the wood of trees from a forest surrounded by intensive agriculture in the vicinity of Greifswald, a medium-sized town in Germany. The aim is to detect historical changes in soil chemistry attributable to either atmospheric depositions or groundwater input of nitrogen or sulphur. Therefore, high-resolution (50 µm) X-ray fluorescence (XRF) analysis is carried out and species-specific annual chronologies of relative concentrations of the most abundant elements as well as of different indicative element-ratios are built. We discuss our findings in the light of ongoing soil acidification that might be responsible for some of the detected trends (e.g. decrease in base cations like Ca or Mn), while considering possible radial translocation processes in the wood that might blur the obtained dendrochemical data.

Trends in polycyclic aromatic hydrocarbon concentrations in the great lakes atmosphere.

PubMed

Sun, Ping; Blanchard, Pierrette; Brice, Kenneth A; Hites, Ronald A

2006-10-15

Atmospheric polycyclic aromatic hydrocarbon (PAHs) concentrations were measured in both the vapor and particle phases at seven sites near the Great Lakes as a part of the Integrated Atmospheric Deposition Network. Lower molecular weight PAHs, including fluorene, phenanthrene, fluoranthrene, and pyrene, were dominant in the vapor phase, and higher molecular weight PAHs, including chrysene, benzo[a]pyrene, and coronene, were dominant in the particle phase. The highest PAH concentrations in both the vapor and particle phases were observed in Chicago followed by the semiurban site at Sturgeon Point, NY. The spatial difference of PAH concentrations can be explained by the local population density. Long-term decreasing trends of most PAH concentrations were observed in both the vapor and particle phases at Chicago, with half-lives ranging from 3-10 years in the vapor phase and 5-15 years in the particle phase. At Eagle Harbor, Sleeping Bear Dunes, and Sturgeon Point, total PAH concentrations in the vapor phase showed significant, but slow, long-term decreasing trends. At the Sturgeon Point site, which was impacted by a nearby city, particle-phase PAH concentrations also declined. However, most particle-phase PAH concentrations did not show significant long-term decreasing trends at the remote sites. Seasonal trends were also observed for particle-phase PAH concentrations, which were higher in the winter and lower in the summer.

Spring onset variations and long-term trends from new hemispheric-scale products and remote sensing

NASA Astrophysics Data System (ADS)

Dye, D. G.; Li, X.; Ault, T.; Zurita-Milla, R.; Schwartz, M. D.

2015-12-01

Spring onset is commonly characterized by plant phenophase changes among a variety of biophysical transitions and has important implications for natural and man-managed ecosystems. Here, we present a new integrated analysis of variability in gridded Northern Hemisphere spring onset metrics. We developed a set of hemispheric temperature-based spring indices spanning 1920-2013. As these were derived solely from meteorological data, they are used as a benchmark for isolating the climate system's role in modulating spring "green up" estimated from the annual cycle of normalized difference vegetation index (NDVI). Spatial patterns of interannual variations, teleconnections, and long-term trends were also analyzed in all metrics. At mid-to-high latitudes, all indices exhibit larger variability at interannual to decadal time scales than at spatial scales of a few kilometers. Trends of spring onset vary across space and time. However, compared to long-term trend, interannual to decadal variability generally accounts for a larger portion of the total variance in spring onset timing. Therefore, spring onset trends identified from short existing records may be aliased by decadal climate variations due to their limited temporal depth, even when these records span the entire satellite era. Based on our findings, we also demonstrated that our indices have skill in representing ecosystem-level spring phenology and may have important implications in understanding relationships between phenology, atmosphere dynamics and climate variability.

Climate change in the Fertile Crescent and implications of the recent Syrian drought

DOE PAGES

Kelley, Colin P.; Mohtadi, Shahrzad; Cane, Mark A.; ...

2015-03-02

Before the Syrian uprising that began in 2011, the greater Fertile Crescent experienced the most severe drought in the instrumental record. For Syria, a country marked by poor governance and unsustainable agricultural and environmental policies, the drought had a catalytic effect, contributing to political unrest. In this paper, we show that the recent decrease in Syrian precipitation is a combination of natural variability and a long-term drying trend, and the unusual severity of the observed drought is here shown to be highly unlikely without this trend. Precipitation changes in Syria are linked to rising mean sea-level pressure in the Easternmore » Mediterranean, which also shows a long-term trend. There has been also a long-term warming trend in the Eastern Mediterranean, adding to the drawdown of soil moisture. No natural cause is apparent for these trends, whereas the observed drying and warming are consistent with model studies of the response to increases in greenhouse gases. Furthermore, model studies show an increasingly drier and hotter future mean climate for the Eastern Mediterranean. Finally, analyses of observations and model simulations indicate that a drought of the severity and duration of the recent Syrian drought, which is implicated in the current conflict, has become more than twice as likely as a consequence of human interference in the climate system.« less

Deteriorating water clarity in shallow waters: Evidence from long term MODIS and in-situ observations

NASA Astrophysics Data System (ADS)

Shi, Kun; Zhang, Yunlin; Zhu, Guangwei; Qin, Boqiang; Pan, Delu

2018-06-01

Water clarity (Secchi disk depth: SDD), as a proxy of water transparency, provides important information on the light availability to the water or lake ecosystem. Shallow lakes have been experienced dramatic environmental and climatic change. This study demonstrated using combination of long-term MODIS and in-situ measurements to track the dynamics of SDD with these environmental and climate changes in shallow water environments. We selected a typical turbid shallow Lake Taihu as our case study. Based on MODIS-Aqua data, an empirical model for estimating SDD was developed and validated. Subsequently, we employed the proposed model to derive the spatial and temporal SDD distribution patterns of Lake Taihu from 2003 to 2015. Combining MODIS-derived SDD time series of 2003-2015 and long-term in-situ SDD observations dated back to 1993, we elucidated SDD long-term variation trends and driving mechanism. Deteriorating water clarity from the long-term SDD observations indicated that Lake Taihu became more and more turbid and water quality was decreasing. Increasing in cyanobacterial bloom area, as a result of decreasing in wind speed and eutrophication, may partially be responsible for the decreasing trend. A predicted future decrease in the wind speed in Lake Taihu region could enhance the formation of cyanobacterial blooms and consequently lead to a further decrease in water clarity. This study suggested that coupling remote sensing monitoring and long-term in-situ observations could provide robust evidence and new insights to elucidate long-term dynamics in aquatic ecosystem evolution.

NASA Contributions to Improve Understanding of Extreme Events in the Global Energy and Water Cycle

NASA Technical Reports Server (NTRS)

Lapenta, William M.

2008-01-01

The U.S. Climate Change Science Program (CCSP) has established the water cycle goals of the Nation's climate change program. Accomplishing these goals will require, in part, an accurate accounting of the key reservoirs and fluxes associated with the global water and energy cycle, including their spatial and temporal variability. through integration of all necessary observations and research tools, To this end, in conjunction with NASA's Earth science research strategy, the overarching long-term NASA Energy and Water Cycle Study (NEWS) grand challenge can he summarized as documenting and enabling improved, observationally based, predictions of water and energy cycle consequences of Earth system variability and change. This challenge requires documenting and predicting trends in the rate of the Earth's water and energy cycling that corresponds to climate change and changes in the frequency and intensity of naturally occurring related meteorological and hydrologic events, which may vary as climate may vary in the future. The cycling of water and energy has obvious and significant implications for the health and prosperity of our society. The importance of documenting and predicting water and energy cycle variations and extremes is necessary to accomplish this benefit to society.

Causes of Glacier Melt Extremes in the Alps Since 1949

NASA Astrophysics Data System (ADS)

Thibert, E.; Dkengne Sielenou, P.; Vionnet, V.; Eckert, N.; Vincent, C.

2018-01-01

Recent record-breaking glacier melt values are attributable to peculiar extreme events and long-term warming trends that shift averages upward. Analyzing one of the world's longest mass balance series with extreme value statistics, we show that detrending melt anomalies makes it possible to disentangle these effects, leading to a fairer evaluation of the return period of melt extreme values such as 2003, and to characterize them by a more realistic bounded behavior. Using surface energy balance simulations, we show that three independent drivers control melt: global radiation, latent heat, and the amount of snow at the beginning of the melting season. Extremes are governed by large deviations in global radiation combined with sensible heat. Long-term trends are driven by the lengthening of melt duration due to earlier and longer-lasting melting of ice along with melt intensification caused by trends in long-wave irradiance and latent heat due to higher air moisture.

The effect of submerged aquatic vegetation expansion on a declining turbidity trend in the Sacramento-San Joaquin River Delta

USGS Publications Warehouse

Hestir, E.L.; Schoellhamer, David H.; Jonathan Greenberg,; Morgan-King, Tara L.; Ustin, S.L.

2016-01-01

Submerged aquatic vegetation (SAV) has well-documented effects on water clarity. SAV beds can slow water movement and reduce bed shear stress, promoting sedimentation and reducing suspension. However, estuaries have multiple controls on turbidity that make it difficult to determine the effect of SAV on water clarity. In this study, we investigated the effect of primarily invasive SAV expansion on a concomitant decline in turbidity in the Sacramento-San Joaquin River Delta. The objective of this study was to separate the effects of decreasing sediment supply from the watershed from increasing SAV cover to determine the effect of SAV on the declining turbidity trend. SAV cover was determined by airborne hyperspectral remote sensing and turbidity data from long-term monitoring records. The turbidity trends were corrected for the declining sediment supply using suspended-sediment concentration data from a station immediately upstream of the Delta. We found a significant negative trend in turbidity from 1975 to 2008, and when we removed the sediment supply signal from the trend it was still significant and negative, indicating that a factor other than sediment supply was responsible for part of the turbidity decline. Turbidity monitoring stations with high rates of SAV expansion had steeper and more significant turbidity trends than those with low SAV cover. Our findings suggest that SAV is an important (but not sole) factor in the turbidity decline, and we estimate that 21–70 % of the total declining turbidity trend is due to SAV expansion.

Do climate model predictions agree with long-term precipitation trends in the arid southwestern United States?

USDA-ARS?s Scientific Manuscript database

Researchers evaluating climate projections across southwestern North America observed a decreasing precipitation trend. Aridification was most pronounced in the cold (non-monsoonal) season, whereas downward trends in precipitation were smaller in the warm (monsoonal) season. In this region, based up...

Time-Series Analysis: A Cautionary Tale

NASA Technical Reports Server (NTRS)

Damadeo, Robert

2015-01-01

Time-series analysis has often been a useful tool in atmospheric science for deriving long-term trends in various atmospherically important parameters (e.g., temperature or the concentration of trace gas species). In particular, time-series analysis has been repeatedly applied to satellite datasets in order to derive the long-term trends in stratospheric ozone, which is a critical atmospheric constituent. However, many of the potential pitfalls relating to the non-uniform sampling of the datasets were often ignored and the results presented by the scientific community have been unknowingly biased. A newly developed and more robust application of this technique is applied to the Stratospheric Aerosol and Gas Experiment (SAGE) II version 7.0 ozone dataset and the previous biases and newly derived trends are presented.

GATEWAY Report Brief: SSL Demonstration: Long-Term Evaluation of Indoor Field Performance

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

None, None

Report brief summarizing a GATEWAY program evaluation of the long-term performance characteristics (chromaticity change, maintained illuminance, and operations and maintenance) of LED lighting systems in four field installations previously documented in separate DOE GATEWAY reports.

Warming trends of perialpine lakes from homogenised time series of historical satellite and in-situ data.

PubMed

Pareeth, Sajid; Bresciani, Mariano; Buzzi, Fabio; Leoni, Barbara; Lepori, Fabio; Ludovisi, Alessandro; Morabito, Giuseppe; Adrian, Rita; Neteler, Markus; Salmaso, Nico

2017-02-01

The availability of more than thirty years of historical satellite data is a valuable source which could be used as an alternative to the sparse in-situ data. We developed a new homogenised time series of daily day time Lake Surface Water Temperature (LSWT) over the last thirty years (1986-2015) at a spatial resolution of 1km from thirteen polar orbiting satellites. The new homogenisation procedure implemented in this study corrects for the different acquisition times of the satellites standardizing the derived LSWT to 12:00 UTC. In this study, we developed new time series of LSWT for five large lakes in Italy and evaluated the product with in-situ data from the respective lakes. Furthermore, we estimated the long-term annual and summer trends, the temporal coherence of mean LSWT between the lakes, and studied the intra-annual variations and long-term trends from the newly developed LSWT time series. We found a regional warming trend at a rate of 0.017°Cyr -1 annually and 0.032°Cyr -1 during summer. Mean annual and summer LSWT temporal patterns in these lakes were found to be highly coherent. Amidst the reported rapid warming of lakes globally, it is important to understand the long-term variations of surface temperature at a regional scale. This study contributes a new method to derive long-term accurate LSWT for lakes with sparse in-situ data thereby facilitating understanding of regional level changes in lake's surface temperature. Copyright © 2016 Elsevier B.V. All rights reserved.

End of Life Strategies Among Patients with Advanced Chronic Obstructive Pulmonary Disease (COPD).

PubMed

Gershon, Andrea S; Maclagan, Laura C; Luo, Jin; To, Teresa; Kendzerska, Tetyana; Stanbrook, Matthew B; Bourbeau, Jean; Etches, Jacob; Aaron, Shawn D

2018-06-11

The burden of advanced COPD is high globally; however, little is known about how often end of life strategies are used by this population. To describe trends in the use of end of life care strategies by people with advanced COPD in Ontario, Canada. A population-based repeated cross-sectional study examining end of life care strategies in individuals with advanced COPD was conducted. Annual proportions of individuals who received formal palliative care, long-term oxygen therapy or opioids from 2004 to 2014 were determined. Results were age- and sex- standardized as well as stratified by age, sex, socioeconomic status, urban/rural residence and immigrant status. Measurement/Main Results: There were 151,912 persons with advanced COPD in Ontario between 2004 and 2014. Use of formal palliative care services increased 1% per year from 5.3% in 2004 to 14.3% in 2014 (p value for trend <0.001), while use of long-term oxygen therapy increased 1.1% per year from 26.4% in 2004 to 35.3% in 2013 (p value for trend <0.001). The use of opioids was relatively stable (40.0% in 2004 and 41.8% in 2014, p value for trend=0.08). Younger individuals were less likely to use formal palliative care services and long-term oxygen therapy. Males were less likely than females to receive long-term oxygen therapy and opioids. The proportion of people with advanced COPD using end of life strategies, although increasing, remains low. Efforts should focus on increasing access to such strategies as well as educating patients and providers of their benefits.

Long-term care for people with developmental disabilities: a critical analysis.

PubMed

Palley, H A; Van Hollen, V

2000-08-01

This article explores how the trends toward long-term community care affecting people with developmental disabilities developed. Appropriateness of care and quality of life issues are discussed. The article also reviews the development of long-term care for frail and disabled elderly people and explores the arguments for a continuum of care that have developed in this area. The authors conclude that future policies with respect to meeting long-term care needs for people with developmental disabilities must be addressed flexibly on an individual basis, related to individual needs, and must provide a continuum of care services.

Short Term Objectives. (SCAT Project, Title VI-G).

ERIC Educational Resources Information Center

Archer, Anita

Developed by the staff of the SCAT (Support, Competency-Assistance and Training) Project, the document deals with the third step of the systematic instructional model--sequencing short term objectives for exceptional students. The manual focuses on reviewing long term goals established by the child study team, converting these goals into long term…

Impacts of Wildfires on Long-term Land Surface Phenology

NASA Astrophysics Data System (ADS)

Wang, J.; Zhang, X.

2016-12-01

Land surface phenology (LSP) detected from satellite data characterizes seasonal dynamics of vegetation communities within a moderate or coarse resolution pixel. Its long-term variation has been widely used to indicate the biological responses to climate changes. However, few studies have focused on the influence of land disturbance on LSP variations. The wildfire is one of the most important drivers of land disturbances across the world, which shows an increasing trend during past decades. To explore the wildfire impacts on LSP, we analyzed post-fire and pre-fire LSP in two forest fire events that are Hayman Fire occurred in 2002 and Mason Fire occurred in 2005 in Colorado. Specifically, we first generated a two band enhanced vegetation index (EVI2) from MODIS daily surface reflectance product (MOD09GQ) at a spatial resolution of 250 m from 2001-2014. The time series of daily EVI2 was then used to detect the start of growing season (SOS) by applying the LSP detection algorithm based on a hybrid piecewise logistic model (HPLM-LSPD). The SOS was further separated for four levels of burn severity obtained from Monitoring Trends in Burn Severity (MTBS) maps for each fire event. The long-term SOS in the burn scars was finally deviated from surrounding areas based on land cover types. Results show that forests were mainly converted to shrubs in both fire events with some grasslands in Hayman. On average, SOS in Hayman burn scar area was advanced 11 days relative to surrounding region while it was delayed 9 days in Mason fire. The deviation also varied with the burn severity spatially. Moreover, the long-term SOS trend in the local area from 2001-2014 was significantly different with and without considerations of the fire influences. This study demonstrates that the long-term LSP SOS trend is significantly influenced by land disturbances in a local and regional scales.

On the relationship between boreal forest browning and tree mortality: insights from Alaska

NASA Astrophysics Data System (ADS)

Rogers, B. M.; Goetz, S. J.

2015-12-01

Long-term satellite measurements of vegetation productivity in high-latitude environments have revealed profound and widespread responses to climate warming. Although warmer and longer summers are causing the Arctic to "green", many regions of boreal forest are showing the opposite response, particularly since the mid 1990s. This "browning" phenomenon was generally unexpected at the time of discovery, is not captured by global models, and may have profound consequences for the boreal biome. A number of studies have linked satellite-based browning trends to tree productivity through tree rings. However, our understanding of the environmental controls and ecosystem consequences of browning remains remarkably limited. Here we examine to what extent browning patterns are related to a fundamental demographic process: tree mortality. We focus on a long-term inventory database in Alaska to characterize mortality events and trends from 1994 to 2014. These patterns were related to vegetation productivity indices from MODIS and the AVHRR-based GIMMS3g data set. We explore three central hypotheses: (1) mortality events are likely to be preceded by 5-10 year browning trends ("press stress"), (2) mortality events are likely to be preceded by distinct pulses of low productivity ("pulse stress"), and (3) long-term trends in mortality are related to long-term browning. Within our study region, which encompasses eastern Alaskan from the Pacific coastal mountains up through the interior, we find strong evidence for the first two hypotheses. The third is weakly supported, which may be a consequence of the episodic nature of mortality in the region. However, preliminary analyses in the southern Canadian boreal reveal a markedly stronger relationship between long-term mortality and browning. Taken together, our study suggests a robust correlation between satellite-based metrics of productivity and forest demography; one that has consequences for forest composition, carbon stocks, and early signs of a biome shift in boreal forests.

Effects of climate variability and human activities on Chesapeake Bay and the implications for ecosystem restoration

USGS Publications Warehouse

Cronin, Thomas M.; Willard, Debra A.; Phillips, Scott

2000-01-01

Chesapeake Bay, the Nation’s largest and most productive estuary (fig. 1), faces complex environmental issues related to nutrients and oxygen, turbidity and sedimentation, toxic dinoflagellates, sea-level rise, and coastal erosion. The Chesapeake Bay Program (CBP) is a partnership among the Chesapeake Bay Commission, the Federal Government, the District of Columbia, and the States of Maryland, Virginia, and Pennsylvania. The CBP is working to preserve, restore, and protect the bay’s living resources, vital habitats, and water quality, to protect human health, and to promote sound land-use policies in the watershed. The CBP began to set restoration goals for the ecosystem in the mid-1980’s and is now refining current goals and setting new ones as part of a new bay agreement— Chesapeake 2000. As the CBP sets restoration goals for the next 10–20 years, it will be critical to understand the long-term changes of the bay ecosystem due to climate variability and the influence of past and future human activities.For the past 4 years, the U.S. Geological Survey (USGS) has been engaged in research designed to provide objective scientific answers to questions about long-term changes in the bay ecosystem: What paleoecological and geochemical methods are best for documenting trends in the bay ecosystem?How does climate variability, including drought, affect the bay?What are historical trends in dissolved oxygen?What is the relationship between sedimentation and water clarity, and what is the effect of turbidity on living resources?How have past land-use changes affected bay habitats and living resources?

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

Blanco, Arthur S.; Gerlagh, Reyer; Suh, Sangwon

Chapter 5 analyzes the anthropogenic greenhouse gas (GHG) emission trends until the present and the main drivers that explain those trends. The chapter uses different perspectives to analyze past GHG-emissions trends, including aggregate emissions flows and per capita emissions, cumulative emissions, sectoral emissions, and territory-based vs. consumption-based emissions. In all cases, global and regional trends are analyzed. Where appropriate, the emission trends are contextualized with long-term historic developments in GHG emissions extending back to 1750.

Farallon de Medinilla seabird and Tinian moorhen analyses

USGS Publications Warehouse

Camp, Richard J.; Leopold, Christina R.; Brinck, Kevin W.; Juola, Franz

2015-01-01

This report assesses the trends in brown booby (Sula leucogaster), masked booby (S. dactylatra), and red-footed booby (S. sula) counts collected on Farallon de Medinilla and Mariana common moorhen (Gallinula chloropus guami) counts on Tinian, Commonwealth of the Northern Mariana Islands to help elucidate patterns in bird numbers. During either monthly or quarterly surveys between 1997 and 2014 counts of all four bird species were recorded, generating a relatively noisy time series revealing inter-annual variation in index counts by as much as 1,000%. For the purposes of assessing long-term population trends across years we chose a single, species-specific month to assess trends. Doing so reduces the effect of intra-annual variation allowing the analysis to focus on inter-annual variation important to long-term trends assessment. There are clear fluctuations in the counts of all four species. Although the trends were non-significant, there is some evidence that masked and red-footed booby species have declined while brown booby and moorhen have increased.

Observations of, and sources of the spatial and temporal variability of ozone in the middle atmosphere on climatological time scales (OZMAP) and equatorial dynamics: Seasonal variations of ozone trends

NASA Technical Reports Server (NTRS)

Entzian, G.; Grasnick, K. H.; Taubenheim, J.

1989-01-01

The long term trends (least square linear regression with time) of ozone content at seven European, seven North American, three Japanese and two tropical stations during 21 years (1964 to 1984) are analyzed. In all regions negative trends are observed during the 1970s, but are partly compensated by limited periods of positive trends during the late 1960s and late 1970s. Solely the North American ozone data show negative trends in all 10 year periods. When the long term ozone trends are evaluated for each month of the year separately, a seasonal variation is revealed, which in Europe and North America has largest negative trends in late winter and spring. While in Europe the negative trends in winter/spring are partly compensated by positive trends in summer, in North America the summer values reach only zero, retaining the significant negative trend in annual mean values. In contrast to the antarctic ozone hole, the spring reduction of ozone in Europe and in North America is associated with stratospheric temperatures increasing in the analyzed period and therefore is consistent with the major natural ozone production and loss processes.

Sandstone: secular trends in lithology in southwestern montana.

PubMed

McLane, M

1972-11-03

Long-term secular trends in the composition and texture of sandstones in southwestern Montana reflect changing provenance and depositional environment, which in turn reflect changing tectonic patterns in the Cordilleran mobile belt just to the west.

Trends in camping participation

Treesearch

Wilbur F. LaPage; Dale P. Ragain; Dale P. Ragain

1971-01-01

Several years ago the Northeastern Forest Experiment Station began a long-term study of per-capita camping participation. The objectives of the research were to identify campers with increasing or decreasing camping participation and to determine the causes of those trends.

Using the North American Breeding Bird Survey as a tool for conservation: A critique of Bart et al. (2004)

USGS Publications Warehouse

Sauer, John R.; Link, William A.; Nichols, James D.; Royle, J. Andrew

2005-01-01

Bart et al. (2004) develop methods for predicting needed samples for estimation of long-term trends from Count survey data, and they apply these methods to the North American Breeding Bird Survey (BBS). They recommend adding approximately 40% more survey routes ill the BBS to allow for estimation of long-term (i.e., 20 year) trends for a collection of species. We critique several aspects of their analysis and suggest that their focus on long-term trends and expansion of the present survey design will provide limited benefits for conservation because it fails to either enhance the credibility of the survey or better tie the survey to regional management activities. A primary innovation claimed by Bart et al. (2004) is the incorporation of bias in estimation of study planning. We question the value of this approach, as it requires reliable estimates of range of future bias. We show that estimates of bias used by Bart et al. (2004) are speculative. Failure to obtain better estimates of this bias is likely to compromise the credibility of future analyses of the survey. We also note that the generic analysis of population trends that they provide is of questionable validity and is unlikely to be relevant for regions and species of management concern.

Long-term sea level trends: Natural or anthropogenic?

NASA Astrophysics Data System (ADS)

Becker, M.; Karpytchev, M.; Lennartz-Sassinek, S.

2014-08-01

Detection and attribution of human influence on sea level rise are important topics that have not yet been explored in depth. We question whether the sea level changes (SLC) over the past century were natural in origin. SLC exhibit power law long-term correlations. By estimating Hurst exponent through Detrended Fluctuation Analysis and by applying statistics of Lennartz and Bunde, we search the lower bounds of statistically significant external sea level trends in longest tidal records worldwide. We provide statistical evidences that the observed SLC, at global and regional scales, is beyond its natural internal variability. The minimum anthropogenic sea level trend (MASLT) contributes to the observed sea level rise more than 50% in New York, Baltimore, San Diego, Marseille, and Mumbai. A MASLT is about 1 mm/yr in global sea level reconstructions that is more than half of the total observed sea level trend during the XXth century.

Long-term performance of a hot in-place recycling project final report.

DOT National Transportation Integrated Search

2016-08-01

This report documents the construction and long-term performance of a hot in-place recycled (HIPR) : project on SR 542. HIPR project selection, mix design, construction and testing are described. It was shown that : the HIPR process successfully reha...

Problems and Issues in Long-Term Care. Hearings before the Subcommittee on Health and the Environment of the Committee on Energy and Commerce. House of Representatives, Ninety-Ninth Congress. Long-Term Care Services for the Elderly (October 18, 1985) and Alzheimer's Disease and Related Disorders (January 27, 1986).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Energy and Commerce.

This document provides testimony from two Congressional hearings, one on the subject of long-term care services for the elderly and the other on Alzheimer's disease and related disorders. In the hearing on long-term care, opening remarks are given by Congressmen Waxman and Wyden. Expert testimony from the following witnesses is provided: (1)…

Bridge scour monitoring methods at three sites in Wisconsin

USGS Publications Warehouse

Walker, John F.; Hughes, Peter E.

2005-01-01

Of the nearly 11,500 bridges in Wisconsin, 89 have been assessed with critical scour conditions. The U.S. Geological Survey, in cooperation with the Wisconsin Department of Transportation, the Marathon County Highway Department, and the Jefferson County Highway Department, performed routine monitoring of streambed elevations for three bridges. Two monitoring approaches were employed: (1) manual monitoring using moderately simple equipment, and (2) automated monitoring, using moderately sophisticated electronic equipment. The results from all three sites demonstrate that both techniques can produce reasonable measurements of streambed elevation. The manual technique has a lower annual operating cost, and is useful for cases where documentation of long-term trends is desired. The automated technique has a higher annual operating cost and is useful for real-time monitoring of episodic events with short time durations. 

Solar cycle and long term variations of mesospheric ice layers

NASA Astrophysics Data System (ADS)

Lübken, Franz-Josef; Berger, Uwe; Kiliani, Johannes; Baumgarten, Gerd; Fiedler, Jens; Gerding, Michael

2010-05-01

Ice layers in the summer mesosphere at middle and polar latitudes, frequently called `noctilucent clouds' (NLC) or `polar mesosphere clouds'(PMC), are considered to be sensitive indicators of long term changes in the middle atmosphere. We present a summary of long term observations from the ground and from satellites and compare with results from the LIMA model (Leibniz Institute Middle Atmosphere Model). LIMA nicely reproduces mean conditions of the summer mesopause region and also mean characteristics of ice layers. LIMA nudges to ECMWF data in the troposphere and lower stratosphere which influences the background conditions in the mesosphere and thereby the morphology of ice clouds. A strong correlation between temperatures and PMC altitudes is observed. Applied to historical measurements this give s negligible temperature trends at PMC altitudes (approximately 0.01-0.02 K/y). Trace gas concentrations are kept constant in LIMA except for water vapor which is modified by variable solar radiation. Still, long term trends in temperatures and ice layer parameters are observed, consistent with observations. As will be shown, these trends originate in the stratosphere. Solar cycle effects are expected in ice layers due to variations in background temperatures and water paper. We will present results from LIMA regarding solar cycle variations and compare with NLC observations at our lidar stations in Kühlungsborn (54°N) and ALOMAR (69°N), and also with satellite measurements.

Globally Increased Crop Growth and Cropping Intensity from the Long-Term Satellite-Based Observations

NASA Astrophysics Data System (ADS)

Chen, Bin

2018-04-01

Understanding the spatiotemporal change trend of global crop growth and multiple cropping system under climate change scenarios is a critical requirement for supporting the food security issue that maintains the function of human society. Many studies have predicted the effects of climate changes on crop production using a combination of filed studies and models, but there has been limited evidence relating decadal-scale climate change to global crop growth and the spatiotemporal distribution of multiple cropping system. Using long-term satellite-derived Normalized Difference Vegetation Index (NDVI) and observed climate data from 1982 to 2012, we investigated the crop growth trend, spatiotemporal pattern trend of agricultural cropping intensity, and their potential correlations with respect to the climate change drivers at a global scale. Results show that 82.97 % of global cropland maximum NDVI witnesses an increased trend while 17.03 % of that shows a decreased trend over the past three decades. The spatial distribution of multiple cropping system is observed to expand from lower latitude to higher latitude, and the increased cropping intensity is also witnessed globally. In terms of regional major crop zones, results show that all nine selected zones have an obvious upward trend of crop maximum NDVI (p < 0.001), and as for climatic drivers, the gradual temperature and precipitation changes have had a measurable impact on the crop growth trend.

Effects of diurnal adjustment on biases and trends derived from inter-sensor calibrated AMSU-A data

NASA Astrophysics Data System (ADS)

Chen, H.; Zou, X.; Qin, Z.

2018-03-01

Measurements of brightness temperatures from Advanced Microwave Sounding Unit-A (AMSU-A) temperature sounding instruments onboard NOAA Polarorbiting Operational Environmental Satellites (POES) have been extensively used for studying atmospheric temperature trends over the past several decades. Intersensor biases, orbital drifts and diurnal variations of atmospheric and surface temperatures must be considered before using a merged long-term time series of AMSU-A measurements from NOAA-15, -18, -19 and MetOp-A.We study the impacts of the orbital drift and orbital differences of local equator crossing times (LECTs) on temperature trends derivable from AMSU-A using near-nadir observations from NOAA-15, NOAA-18, NOAA-19, and MetOp-A during 1998-2014 over the Amazon rainforest. The double difference method is firstly applied to estimation of inter-sensor biases between any two satellites during their overlapping time period. The inter-calibrated observations are then used to generate a monthly mean diurnal cycle of brightness temperature for each AMSU-A channel. A diurnal correction is finally applied each channel to obtain AMSU-A data valid at the same local time. Impacts of the inter-sensor bias correction and diurnal correction on the AMSU-A derived long-term atmospheric temperature trends are separately quantified and compared with those derived from original data. It is shown that the orbital drift and differences of LECTamong different POESs induce a large uncertainty in AMSU-A derived long-term warming/cooling trends. After applying an inter-sensor bias correction and a diurnal correction, the warming trends at different local times, which are approximately the same, are smaller by half than the trends derived without applying these corrections.

Recovery from chronic and snowmelt acidification: Long-term trends in stream and soil water chemistry at the Hubbard Brook Experimental Forest, New Hampshire, USA

NASA Astrophysics Data System (ADS)

Fuss, Colin B.; Driscoll, Charles T.; Campbell, John L.

2015-11-01

Atmospheric acid deposition of sulfate and nitrate has declined markedly in the northeastern United States due to emissions controls. We investigated long-term trends in soil water (1984-2011) and stream water (1982-2011) chemistry along an elevation gradient of a forested watershed to evaluate the progress of recovery of drainage waters from acidic deposition at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, USA. We found slowed losses of base cations from soil and decreased mobilization of dissolved inorganic aluminum. Stream water pH at the watershed outlet increased at a rate of 0.01 units yr-1, and the acid neutralizing capacity (ANC) gained 0.88 µeq L-1 yr-1. Dissolved organic carbon generally decreased in stream water and soil solutions, contrary to trends observed at many North American and European sites. We compared whole-year hydrochemical trends with those during snowmelt, which is the highest-flow and lowest ANC period of the year, indicative of episodic acidification. Stream water during snowmelt had long-term trends of increasing ANC and pH at a rate very similar to the whole-year record, with closely related steady decreases in sulfate. A more rapid decline in stream water nitrate during snowmelt compared with the whole-year trend may be due, in part, to the marked decrease in atmospheric nitrate deposition during the last decade. The similarity between the whole-year trends and those of the snowmelt period is an important finding that demonstrates a consistency between recovery from chronic acidification during base flow and abatement of snowmelt acidification.

Global Water Surface Dynamics: Toward a Near Real Time Monitoring Using Landsat and Sentinel Data

NASA Astrophysics Data System (ADS)

Pekel, J. F.; Belward, A.; Gorelick, N.

2017-12-01

Global surface water dynamics and its long-term changes have been documented at 30m spatial resolution using the entire multi-temporal orthorectified Landsat 5, 7 and 8 archive for the years 1984 to 2015. This validated dataset recorded the months and years when water was present, where occurrence changed and what form changes took (in terms of seasonality), documents inter-annual variability, and multi-annual trends. This information is freely available from the global surface water explorer https://global-surface-water.appspot.com. Here we extend this work (doi:10.1038/nature20584 ) by combining post 2015 Landsat 7 and 8 data with imagery from the Copernicus program's Sentinel 2a and b satellites. Using these data in combination improves the spatial resolution (from 30m to a nominal 10m) and temporal resolution (from 8 days to 4 days revisit time at the equator). The improved geographic and temporal completeness of the combined Landsat / Sentinel dataset also offers new opportunities for the identification and characterization of seasonally occurring waterbodies. These improvements are also being examined in the light of reporting progress against Agenda 2030's Sustainable Development Goal 6, especially the indicator used to measure 'change in the extent of water-related ecosystems over time'.

Difficulties in tracking the long-term global trend in tropical forest area.

PubMed

Grainger, Alan

2008-01-15

The long-term trend in tropical forest area receives less scrutiny than the tropical deforestation rate. We show that constructing a reliable trend is difficult and evidence for decline is unclear, within the limits of errors involved in making global estimates. A time series for all tropical forest area, using data from Forest Resources Assessments (FRAs) of the United Nations Food and Agriculture Organization, is dominated by three successively corrected declining trends. Inconsistencies between these trends raise questions about their reliability, especially because differences seem to result as much from errors as from changes in statistical design and use of new data. A second time series for tropical moist forest area shows no apparent decline. The latter may be masked by the errors involved, but a "forest return" effect may also be operating, in which forest regeneration in some areas offsets deforestation (but not biodiversity loss) elsewhere. A better monitoring program is needed to give a more reliable trend. Scientists who use FRA data should check how the accuracy of their findings depends on errors in the data.

Long-Term Assessment of Critical Radionuclides and Associated Environmental Media at the Savannah River Site - 13038

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

Jannik, G.T.; Baker, R.A.; Lee, P.L.

2013-07-01

During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities. However, only a relatively small number of the released radionuclides have been significant contributors to doses and risks to the public. At SRS dose and risk assessments indicate tritium oxide in air and surface water, and Cs-137 in fish and deer have been, and continue to be, the critical radionuclides and pathways. In this assessment, statistical analyses of the long-term trends of tritium oxide in atmospheric and surface water releases and Cs-137 concentrations in fish and deer are provided. Correlations alsomore » are provided with 1) operational changes and improvements, 2) geopolitical events (Cold War cessation), and 3) recent environmental remediation projects and decommissioning of excess facilities. For example, environmental remediation of the F- and H-Area Seepage Basins and the Solid Waste Disposal Facility have resulted in a measurable impact on the tritium oxide flux to the onsite Fourmile Branch stream. Airborne releases of tritium oxide have been greatly affected by operational improvements and the end of the Cold War in 1991. However, the effects of SRS environmental remediation activities and ongoing tritium operations on tritium concentrations in the environment are measurable and documented in this assessment. Controlled hunts of deer and feral hogs are conducted at SRS for approximately six weeks each year. Before any harvested animal is released to a hunter, SRS personnel perform a field analysis for Cs-137 concentrations to ensure the Hunter's dose does not exceed the SRS administrative game limit of 0.22 milli-sievert (22 mrem). However, most of the Cs-137 found in SRS onsite deer is not from site operations but is from nuclear weapons testing fallout from the 1950's and early 1960's. This legacy source term is trended in the SRS deer, and an assessment of the 'effective' half-life of Cs-137 in deer (including the physical decay half-life and the environmental dispersion half-life) is provided. The 'creek mouth' fisherman is the next most critical pathway at SRS. On an annual basis, three species of fish (panfish, catfish, and bass) are sampled from the mouths of the five SRS streams. Three composites of up to five fish of each species are analyzed from each sampling location. Long-term trending of the Cs-137 concentrations in fish and the subsequent doses from consumption of SRS fish is provided. (authors)« less

Long-Term Assessment of Critical Radionuclides and Associated Environmental Media at the Savannah River Site

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

Jannik, G. T.; Baker, R. A.; Lee, P. L.

2012-11-06

During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities. However, only a relatively small number of the released radionuclides have been significant contributors to doses and risks to the public. At SRS dose and risk assessments indicate tritium oxide in air and surface water, and Cs-137 in fish and deer have been, and continue to be, the critical radionuclides and pathways. In this assessment, indepth statistical analyses of the long-term trends of tritium oxide in atmospheric and surface water releases and Cs-137 concentrations in fish and deer are provided. Correlationsmore » also are provided with 1) operational changes and improvements, 2) geopolitical events (Cold War cessation), and 3) recent environmental remediation projects and decommissioning of excess facilities. For example, environmental remediation of the F- and H-Area Seepage Basins and the Solid Waste Disposal Facility have resulted in a measurable impact on the tritium oxide flux to the onsite Fourmile Branch stream. Airborne releases of tritium oxide have been greatly affected by operational improvements and the end of the Cold War in 1991. However, the effects of SRS environmental remediation activities and ongoing tritium operations on tritium concentrations in the environment are measurable and documented in this assessment. Controlled hunts of deer and feral hogs are conducted at SRS for approximately six weeks each year. Before any harvested animal is released to a hunter, SRS personnel perform a field analysis for Cs-137 concentrations to ensure the hunter's dose does not exceed the SRS administrative game limit of 0.22 millisievert (22 mrem). However, most of the Cs-137 found in SRS onsite deer is not from site operations but is from nuclear weapons testing fallout from the 1950's and early 1960's. This legacy source term is trended in the SRS deer, and an assessment of the ''effective'' half-life of Cs-137 in deer (including the physical decay half-life and the environmental dispersion half-life) is provided. The ''creek mouth'' fisherman is the next most critical pathway at SRS. On an annual basis, three species of fish (panfish, catfish, and bass) are sampled from the mouths of the five SRS streams. Three composites of up to five fish of each species are analyzed from each sampling location. Long-term trending of the Cs-137 concentrations in fish and the subsequent doses from consumption of SRS fish is provided.« less

Labour Flexibility and Older Worker Marginalisation: The Need for a New Strategy.

ERIC Educational Resources Information Center

Standing, Guy

1986-01-01

This article argues that with the growth of flexible labor arrangements, older workers' long-term position in the labor force is being seriously eroded. The author considers the factors behind this trend and then examines possible remedial policies. He concludes by considering one long-term policy that might work. (CT)

Analyzing the Effects of Horizontal Resolution on Long-Term Coupled WRF-CMAQ Simulations

EPA Science Inventory

The objective of this study is to determine the adequacy of using a relatively coarse horizontal resolution (i.e. 36 km) to simulate long-term trends of pollutant concentrations and radiation variables with the coupled WRF-CMAQ model. To this end, WRF-CMAQ simulations over the co...

The California Higher Education Policy Vacuum. The Example of Student Fees.

ERIC Educational Resources Information Center

Callan, Patrick M.

California state legislators are showing a lack of long-term leadership and vision in their planning for the state's higher education needs as indicated in their recent decisions regarding increased tuition and fees. California's public higher education system stands at the nexus of two powerful trends: the long-term social, demographic,…

Exploring Low-Amplitude, Long-Duration Deformational Transients on the Cascadia Subduction Zone

NASA Astrophysics Data System (ADS)

Nuyen, C.; Schmidt, D. A.

2017-12-01

The absence of long-term slow slip events (SSEs) in Cascadia is enigmatic on account of the diverse group of subduction zone systems that do experience long-term SSEs. In particular, southwest Japan, Alaska, New Zealand and Mexico have observed long-term SSEs, with some of the larger events exhibiting centimeter-scale surface displacements over the course of multiple years. The conditions that encourage long-term slow slip are not well established due to the variability in thermal parameter and plate dip amongst subduction zones that host long-term events. The Cascadia Subduction Zone likely has the capacity to host long-term SSEs, and the lack of such events motivates further exploration of the observational data. In order to search for the existence of long-duration transients in surface displacements, we examine Cascadia GPS time series from PANGA and PBO to determine whether or not Cascadia has hosted a long-term slow slip event in the past 20 years. A careful review of the time series does not reveal any large-scale multi-year transients. In order to more clearly recognize possible small amplitude long-term SSEs in Cascadia, the GPS time series are reduced with two separate methods. The first method involves manually removing (1) continental water loading terms, (2) transient displacements of known short-term SSEs, and (3) common mode signals that span the network. The second method utilizes a seasonal-trend decomposition procedure (STL) to extract a long-term trend from the GPS time-series. Manual inspection of both of these products reveals intriguing long-term changes in the longitudinal component of several GPS stations in central Cascadia. To determine whether these shifts could be due to long-term slow slip, we invert the reduced surface displacement time series for fault slip using a principle component analysis-based inversion method. We also utilize forward fault models of various synthetic long-term SSEs to better understand how these events may appear in the time series for a range of magnitudes and durations. Results from this research have direct implications for the possible slip modes in Cascadia and how variations in slip over time can impact stress and strain accumulations along the margin.

[Variation characteristics of maize yield and fertilizer utilization rate on an upland yellow soil under long term fertilization].

PubMed

Luo, Long-Zao; Li, Yu; Zhang, Wen-An; Xiao, Hou-Jun; Jiang, Tai-Ming

2013-10-01

An analysis was made on the 16-year experimental data from the long term fertilization, experiment of maize on a yellow soil in Guizhou of Southwest China. Four treatments, i. e. , no fertilization (CK), chemical fertilization (165 kg N x hm(-2), 82.5 kg P2O5 x hm(-2), and 82.5 kg K2O x hm(-2), NPK), organic manure (30555 kg x hm(-2), M), and combined applicatioin of chemical fertilizers and organic manure (NPKM), were selected to analyze the variation trends of maize yield and fertilizer use efficiency on yellow soil under effects of different long term fertilization modes, aimed to provide references for evaluating and establishing long term fertilization mode and promote the sustainable development of crop production. Overall, the maize yield under long term fertilization had an increasing trend, with a large annual variation. Treatment NPKM had the best yield-increasing effect, with the maize yield increased by 4075.71 kg x hm(-2) and the increment being up to 139.2%. Long term fertilization increased the fertilizer utilization efficiency of maize. In treatment M, the nitrogen and phosphorus utilization rates were increased significantly by 35.4% and 18.8%, respectively. Treatment NPK had obvious effect in improving potassium utilization rate, with an increment of 20% and being far higher than that in treatments M (8.7%) and NPKM (9.2%). The results showed that long term fertilization, especially the combined application of chemical fertilizers and organic manure, was of great importance in increasing crop yield and fertilizer use efficiency.

Trend in land degradation has been the most contended issue in the Sahel. Trends documented have not been consistent across authors and science disciplines, hence little agreement has been gained on the magnitude and direction of land degradation in the Sahel. Differentiated science outputs are related to methods and data used at various scales.

NASA Astrophysics Data System (ADS)

Mbow, C.; Brandt, M.; Fensholt, R.; Ouedraogo, I.; Tagesson, T.

2015-12-01

Thematic gaps in land degradation trends in the SahelTrend in land degradation has been the most contended issue for arid and semi-arid regions. In the Sahel, depending to scale of analysis and methods and data used, the trend documented have not been consistent across authors and science disciplines. The assessment of land degradation and the quantification of its effects on land productivity have been assessed for many decades, but little agreement has been gained on the magnitude and direction in the Sahel. This lack of consistency amid science outputs can be related to many methodological underpinnings and data used for various scales of analysis. Assessing biophysical trends on the ground requires long-term ground-based data collection to evaluate and better understand the mechanisms behind land dynamics. The Sahel is seen as greening by many authors? Is that greening geographically consistent? These questions enquire the importance of scale analysis and related drivers. The questions addressed are not only factors explaining loss of tree cover but also regeneration of degraded land. The picture used is the heuristic cycle model to assess loss and damages vs gain and improvements of various land use practices. The presentation will address the following aspects - How much we know from satellite data after 40 years of remote sensing analysis over the Sahel? That section discuss agreement and divergences of evidences and differentiated interpretation of land degradation in the Sahel. - The biophysical factors that are relevant for tracking land degradation in the Sahel. Aspects such detangling human to climate factors and biophysical factors behind land dynamics will be presented - Introduce some specific cases of driver of land architecture transition under the combined influence of climate and human factor. - Based on the above we will conclude with some key recommendations on how to improve land degradation assessment in the Arid region of the Sahel.

Discriminatory Discipline: Trends and Issues

ERIC Educational Resources Information Center

Whitford, Denise K.; Katsiyannis, Antonis; Counts, Jennifer

2016-01-01

Discriminatory discipline has been widely documented for decades, yet little progress has been made to narrow the gap. Due to the long-standing history of discriminatory discipline, current nationwide data, and recent federal initiatives, there is a need for a comprehensive examination of this critical issue. Therefore, we discuss populations…

Effects of trawl selectivity and genetic parameters on fish body length under long-term trawling

NASA Astrophysics Data System (ADS)

Yu, Yang; Sun, Peng; Cui, He; Sheng, Huaxiang; Zhao, Fenfang; Tang, Yanli; Chen, Zelin

2015-10-01

Long-term fishing pressure affects the biological characteristics of exploited fish stocks. The biological characteristics of hairtail ( Trichiurus lepturus) in the East China Sea are unable to recover because of long-term trawling. Fishing induces evolutionary effects on the fish's biological characteristics. Evidence of these changes includes small size at age, a shift to earlier age structure, and early maturation. Natural and artificial selection usually affect the fish's life history. Selection can induce different chances of reproduction, and individual fish can give a different genetic contribution to the next generation. In this study, analysis of time-dependent probability of significance and test of sensitivity were used to explore the effects of fish exploitation rate, mesh size, and heritability with long-term trawling. Results showed that fishing parameters were important drivers to exploited fish population. However, genetic traits altered by fishing were slow, and the changes in biological characteristics were weaker than those caused by fishing selection. Exploitation rate and mesh size exhibited similar evolutionary trend tendency under long-term fishing. The time-dependent probability of significance trend showed a gradual growth and tended to be stable. Therefore, the direction of fishing-induced evolution and successful management of fish species require considerable attention to contribute to sustainable fisheries in China.

Long-term trend of satellite-observed significant wave height and impact on ecosystem in the East/Japan Sea

NASA Astrophysics Data System (ADS)

Woo, Hye-Jin; Park, Kyung-Ae

2017-09-01

Significant wave height (SWH) data of nine satellite altimeters were validated with in-situ SWH measurements from buoy stations in the East/Japan Sea (EJS) and the Northwest Pacific Ocean. The spatial and temporal variability of extreme SWHs was investigated by defining the 90th, 95th, and 99th percentiles based on percentile analysis. The annual mean of extreme SWHs was dramatically increased by 3.45 m in the EJS, which is significantly higher than the normal mean of about 1.44 m. The spatial distributions of SWHs showed significantly higher values in the eastern region of the EJS than those in the western part. Characteristic seasonality was found from the time-series SWHs with high SWHs (>2.5 m) in winter but low values (<1 m) in summer. The trends of the normal and extreme (99th percentile) SWHs in the EJS had a positive value of 0.0056 m year-1 and 0.0125 m year-1, respectively. The long-term trend demonstrated that higher SWH values were more extreme with time during the past decades. The predominant spatial distinctions between the coastal regions in the marginal seas of the Northwest Pacific Ocean and open ocean regions were presented. In spring, both normal and extreme SWHs showed substantially increasing trends in the EJS. Finally, we first presented the impact of the long-term trend of extreme SWHs on the marine ecosystem through vertical mixing enhancement in the upper ocean of the EJS.

Status and trends monitoring of the mainstem Columbia River: sample frame development and review of programs relevant to the development of an integrated approach to monitoring

USGS Publications Warehouse

Counihan, Timothy D.; Hardiman, Jill M.; Waste, Stephen

2013-01-01

Implementing an Integrated Status and Trends Monitoring program (ISTM) for the mainstem Columbia River will help identify trends in important natural resources and help us understand the long-term collective effects of management actions. In this report, we present progress towards the completion of a stepwise process that will facilitate the development of an ISTM for the mainstem Columbia River. We discuss planning and regulatory documents that can be used to identify monitoring goals and objectives and present existing monitoring and research activities that should be considered as the development of a Columbia River ISTM proceeds. We also report progress towards the development of sample frames for the Columbia and Snake Rivers and their floodplains. The sample frames were formulated using Digital Elevation Models (DEM’s) of the river channel and upland areas and a Generalized Random-Tessellation Stratified (GRTS) algorithm for an area based resource to generate “master sample(s).” Working with the Pacific Northwest Aquatic Monitoring Partnership (PNAMP) we facilitated the transfer of the sample frames to the PNAMP “Monitoring Sample Designer” tool. We then discuss aspects of response and survey designs as they pertain to the formulation of a mainstem Columbia River ISTM. As efforts to formulate an ISTM for the mainstem Columbia River proceed, practitioners should utilize the extensive literature describing the planning and implementation of fish and wildlife mitigation and recovery efforts in the Columbia River Basin. While we make progress towards establishing an ISTM framework, considerable work needs to be done to formulate an ISTM program for the mainstem Columbia River. Long-term monitoring programs have been established for other large rivers systems; scientists that have experience planning, implementing, and maintaining large river monitoring efforts such as those in the Colorado, Illinois, and Mississippi Rivers should be consulted and involved as efforts proceed.

Vitamin E and selenium supplementation and risk of prostate cancer in the Vitamins and lifestyle (VITAL) study cohort.

PubMed

Peters, Ulrike; Littman, Alyson J; Kristal, Alan R; Patterson, Ruth E; Potter, John D; White, Emily

2008-02-01

Vitamin E and selenium are promising nutrients for the prevention of prostate cancer, and both are currently being tested in a large randomized trial for prostate cancer. However, results are not expected for at least 6 years. We aimed to investigate the association of vitamin E and selenium supplementation with prostate cancer in the VITamins And Lifestyle (VITAL) study, a cohort study specifically designed to examine supplement use and future cancer risk. In a prospective design, 35,242 men recruited between 2000 and 2002 from western Washington State completed a questionnaire, including detailed questions about vitamin E and selenium supplement intake during the past 10 years from brand-specific multivitamins and single supplements. Using linkage to the western Washington SEER cancer registry, we documented 830 new cases of prostate cancer from baseline through December 2004. A 10-year average intake of supplemental vitamin E was not associated with a reduced prostate cancer risk overall [hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.65-1.1 for > or =400 IU/day vs. non-use, p for trend 0.36]; however, risk for advanced prostate cancer (regionally invasive or distant metastatic, n = 123) decreased significantly with greater intake of supplemental vitamin E (HR 0.43, 95% CI 0.19-1.0 for 10-year average intake > or =400 IU/day vs. non-use, p for trend 0.03). There was no association between selenium supplementation and prostate cancer risk (HR 0.90, 95% CI 0.62-1.3 for 10-year average intake >50 microg/day vs. non-use, p for trend 0.97). In this prospective cohort, long-term supplemental intake of vitamin E and selenium were not associated with prostate cancer risk overall; however, risk of clinically relevant advanced disease was reduced with greater long-term vitamin E supplementation.

Interactions between lithology and biology drive the long-term response of stream chemistry to major hurricanes in a tropical landscape

Treesearch

W.H. McDowell; R.L. Brereton; F.N. Scatena; J.B. Shanley; N.V. Brokaw; A.E. Lugo

2013-01-01

Humid tropical forests play a dominant role in many global biogeochemical cycles, yet long-term records of tropical stream chemistry and its response to disturbance events such as severe storms and droughts are rare. Here we document the long-term variability in chemistry of two streams in the Luquillo Mountains, Puerto Rico over a period of 27 years. Our two focal...

Climate-induced variations of geyser periodicity in Yellowstone National Park, USA

USGS Publications Warehouse

Hurwitz, S.; Kumar, A.; Taylor, R.; Heasler, H.

2008-01-01

The geysers of Yellowstone National Park, United States, attract millions of visitors each year, and their eruption dynamics have been the subject of extensive research for more than a century. Although many of the fundamental aspects associated with the dynamics of geyser eruptions have been elucidated, the relationship between external forcing (Earth tides, barometric pressure, and precipitation) and geyser eruption intervals (GEIs) remains a matter of ongoing debate. We present new instrumental GEI data and demonstrate, through detailed time-series analysis, that geysers respond to both long-term precipitation trends and to the seasonal hydrologic cycle. Responsiveness to long-term trends is reflected by a negative correlation between the annual averages of GEIs and stream flow in the Madison River. This response is probably associated with long-term pressure changes in the underlying hydrothermal reservoir. We relate seasonal GEI lengthening to snowmelt recharge. ?? 2008 The Geological Society of America.

20 year long term air quality trends in Israel

NASA Astrophysics Data System (ADS)

Luria, M.

2017-12-01

The Israeli air monitoring network was established in the mid 1990's with dozens of measuring sites near most populated areas. During these past 20 years the Israel economy has increased significantly. The population grew by 30%, energy consumption and power generation by more than 40% and the number of motor vehicles increased by nearly 50%. Most of the fossil energy is consumed by the electric power industry that has changed immensely during this period. Until the early 2000's the vast majority of the electricity was generated from coal and heavy oil. However, during the last ten years natural gas has gradually becomes the major source for power generation and for most of the heavy industry. In the present study we examined the impact of these economic trends on the major criteria air pollution parameters; O3, NOx, SO2 and PM10. The analyses was based on the long term trend of median value (50th percentile) and the 90th percentile. The results revealed that SO2 levels throughout the country decreased to very low levels, with the 90th percentile near the detection limit. The levels of PM10, that are relatively high compare with other global regions, did not show any trend during the 20 year period. This is consistent with the fact that most particulate matter results from long range transport of dust from the surrounding deserts. The long term trend of NOx indicates a gradual and steady increase at most measuring sites, which is consistent with the increase of fossil fuel consumption. The increase in NOx levels is most likely the cause for the significant increase in O3 levels found at most sites in a few of them to levels that are considered as an environmental hazard.

A new record of Atlantic sea surface salinity from 1896-2013 reveals the signatures of climate variability and long-term trends

NASA Astrophysics Data System (ADS)

Friedman, A. R.; Reverdin, G. P.; Khodri, M.; Gastineau, G.

2017-12-01

In the North Atlantic, sea surface salinity is both an indicator of the hydrological cycle and an active component of the ocean circulation. As an indirect "ocean rain gauge", surface salinity reflects the net surface fluxes of evaporation - precipitation + runoff, along with advection and vertical mixing. Subpolar surface salinity also may influence the strength of deep convection and the Atlantic Meridional Overturning Circulation (AMOC). However, continuous surface salinity time series beginning before the 1950s are rare, limiting our ability to resolve modes of variability and long-term trends. Here, we present a new gridded surface salinity record in the Atlantic from 1896-2013, compiled from a variety of historical sources. The compilation covers most of the Atlantic from 20°S-70°N, at 100-1000 km length scale and interannual temporal resolution, allowing us to resolve major modes of variability and linkages with large-scale Atlantic climate variations. We find that the low-latitude (tropical and subtropical) Atlantic and the subpolar Atlantic surface salinity are negatively correlated, with subpolar anomalies leading low-latitude anomalies by about a decade. Subpolar surface salinity varies in phase with the Atlantic Multidecadal Oscillation (AMO), whereas low-latitude surface salinity lags the AMO and varies in phase with the low-frequency North Atlantic Oscillation (NAO). Additionally, northern tropical surface salinity is anticorrelated with the AMO and with Sahel rainfall, suggesting that it reflects the latitude of the Intertropical Convergence Zone. The 1896-2013 long-term trend features an amplification of the mean Atlantic surface salinity gradient pattern, with freshening in the subpolar Atlantic and salinification in the tropical and subtropical Atlantic. We find that regressing out the AMO and the low-frequency NAO has little effect on the long-term residual trend. The spatial trend structure is consistent with the "rich-get-richer" hydrological cycle intensification response to global warming, and may also indicate increased Arctic cryosphere melting and surface runoff.

Long-term impact of precision agriculture on a farmer’s field

USDA-ARS?s Scientific Manuscript database

Targeting management practices and inputs with precision agriculture has high potential to meet some of the grand challenges of sustainability in the coming century. Although potential is high, few studies have documented long-term effects of precision agriculture on crop production and environmenta...

Effects of hurricanes and climate oscillations on annual variation in reproduction in wet forest, Puerto Rico.

PubMed

Zimmerman, Jess K; Hogan, James Aaron; Nytch, Christopher J; Bithorn, John E

2018-06-01

Interannual changes in global climate and weather disturbances may influence reproduction in tropical forests. Phenomena such as the El Niño Southern Oscillation (ENSO) are known to produce interannual variation in reproduction, as do severe storms such as hurricanes. Using stationary trap-based phenology data collected fortnightly from 1993 to 2014 from a hurricane-affected (1989 Hugo, 1998 Georges) subtropical wet forest in northeastern Puerto Rico, we conducted a time series analysis of flowering and seed production. We addressed (1) the degree to which interannual variation in flower and seed production was influenced by global climate drivers and time since hurricane disturbance, and (2) how long-term trends in reproduction varied with plant lifeform. The seasonally de-trended number of species in flower fluctuated over time while the number of species producing seed exhibited a declining trend, one that was particularly evident during the second half of the study period. Lagged El Niño indices and time series hurricane disturbance jointly influenced the trends in numbers of flowering and fruiting species, suggesting complex global influences on tropical forest reproduction with variable periodicities. Lag times affecting flowering tended to be longer than those affecting fruiting. Long-term patterns of reproduction in individual lifeforms paralleled the community-wide patterns, with most groups of lifeform exhibiting a long-term decline in seed but not flower production. Exceptions were found for hemiepiphytes, small trees, and lianas whose seed reproduction increased and then declined over time. There was no long-term increase in flower production as reported in other Neotropical sites. © 2018 by the Ecological Society of America.

Validation of Spacecraft Active Cavity Radiometer Total Solar Irradiance (TSI) Long Term Measurement Trends Using Proxy TSI Least Squares Analyses

NASA Technical Reports Server (NTRS)

Lee, Robert Benjamin, III; Wilson, Robert S.

2003-01-01

Long-term, incoming total solar irradiance (TSI) measurement trends were validated using proxy TSI values, derived from indices of solar magnetic activity. Spacecraft active cavity radiometers (ACR) are being used to measure longterm TSI variability, which may trigger global climate changes. The TSI, typically referred to as the solar constant, was normalized to the mean earth-sun distance. Studies of spacecraft TSI data sets confirmed the existence of a 0.1 %, long-term TSI variability component within a 10-year period. The 0.1% TSI variability component is clearly present in the spacecraft data sets from the 1984-2004 time frame. Typically, three overlapping spacecraft data sets were used to validate long-term TSI variability trends. However, during the years of 1978-1984, 1989-1991, and 1993-1996, three overlapping spacecraft data sets were not available in order to validate TSI trends. The TSI was found to vary with indices of solar magnetic activity associated with recent 10-year sunspot cycles. Proxy TSI values were derived from least squares analyses of the measured TSI variability with the solar indices of 10.7-cm solar fluxes, and with limb-darked sunspot fluxes. The resulting proxy TSI values were compared to the spacecraft ACR measurements of TSI variability to detect ACR instrument degradation, which may be interpreted as TSI variability. Analyses of ACR measurements and TSI proxies are presented primarily for the 1984-2004, Earth Radiation Budget Experiment (ERBE) ACR solar monitor data set. Differences in proxy and spacecraft measurement data sets suggest the existence of another TSI variability component with an amplitude greater than or equal to 0.5 Wm-2 (0.04%), and with a cycle of 20 years or more.

Implications of Version 8 TOMS and SBUV Data for Long-Term Trend Analysis

NASA Technical Reports Server (NTRS)

Frith, Stacey M.

2004-01-01

Total ozone data from the Total Ozone Mapping Spectrometer (TOMS) and profile/total ozone data from the Solar Backscatter Ultraviolet (SBUV; SBW/2) series of instruments have recently been reprocessed using new retrieval algorithms (referred to as Version 8 for both) and updated calibrations. In this paper, we incorporate the Version 8 data into a TOMS/SBW merged total ozone data set and an S B W merged profile ozone data set. The Total Merged Ozone Data (Total MOD) combines data from multiple TOMS and SBW instruments to form an internally consistent global data set with virtually complete time coverage from October 1978 through December 2003. Calibration differences between instruments are accounted for using external adjustments based on instrument intercomparisons during overlap periods. Previous results showed errors due to aerosol loading and sea glint are significantly reduced in the V8 TOMS retrievals. Using SBW as a transfer standard, calibration differences between V8 Nimbus 7 and Earth Probe TOMS data are approx. 1.3%, suggesting small errors in calibration remain. We will present updated total ozone long-term trends based on the Version 8 data. The Profile Merged Ozone Data (Profile MOD) data set is constructed using data from the SBUV series of instruments. In previous versions, SAGE data were used to establish the long-term external calibration of the combined data set. The SBW Version 8 we assess the V8 profile data through comparisons with SAGE and between SBW instruments in overlap periods. We then construct a consistently-calibrated long term time series. Updated zonal mean trends as a function of altitude and season from the new profile data set will be shown, and uncertainties in determining the best long-term calibration will be discussed.

76 FR 18807 - Proposed Generic Communication; Licensee Justification of Long-Term Surveillance Charge

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-05

... Documents Access and Management System (ADAMS) under accession number ML102080569. DATES: Comment period... and Management System (ADAMS): Publicly available documents created or received at the NRC are...-25,'' dated September 1980 (Agencywide Documents Access and Management System [ADAMS] accession...

Cloud Ablation by a Relativistic Jet and the Extended Flare in CTA 102 in 2016 and 2017

NASA Astrophysics Data System (ADS)

Zacharias, M.; Böttcher, M.; Jankowsky, F.; Lenain, J.-P.; Wagner, S. J.; Wierzcholska, A.

2017-12-01

In late 2016 and early 2017, the flat spectrum radio quasar CTA 102 exhibited a very strong and long-lasting outburst. The event can be described by a roughly two-month long increase of the baseline flux in the monitored energy bands (optical to γ-rays) by a factor 8, and a subsequent decrease over another two months back to pre-flare levels. The long-term trend was superseded by short but very strong flares, resulting in a peak flux that was a factor 50 above pre-flare levels in the γ-ray domain and almost a factor 100 above pre-flare levels in the optical domain. In this paper, we explain the long-term evolution of the outburst by the ablation of a gas cloud penetrating the relativistic jet. The slice-by-slice ablation results in a gradual increase of the particle injection until the center of the cloud is reached, after which the injected number of particles decreases again. With reasonable cloud parameters, we obtain excellent fits of the long-term trend.

Stratospheric effects on trends of mesospheric ice clouds (Invited)

NASA Astrophysics Data System (ADS)

Luebken, F.; Baumgarten, G.; Berger, U.

2009-12-01

Ice layers in the summer mesosphere at middle and polar latitudes appear as `noctilucent clouds' (NLC) and `polar mesosphere clouds'(PMC) when observed by optical methods from the ground or from satellites, respectively. A newly developed model of the atmosphere called LIMA (Leibniz Institute Middle Atmosphere Model) nicely reproduces the mean conditions of the summer mesopause region and is used to study the ice layer morphology (LIMA/ice). LIMA nudges to ECMWF data in the troposphere and lower stratosphere which influences the background conditions in the mesosphere and ice cloud morphology. Since ice layer formation is very sensitive to the thermal structure of the mesopause region the morphology of NLC and PMC is frequently discussed in terms of long term variations. Model runs of LIMA/ice are now available for 1961 until 2008. A strong correlation between temperatures and PMC altitudes is observed. Applied to historical measurements this gives negligible temperature trends at PMC altitudes (approximately 0.01-0.02 K/y). Trace gas concentrations are kept constant in LIMA except for water vapor which is modified by variable solar radiation. Still, long term trends in temperatures and ice layer parameters are observed, consistent with observations. We present results regarding inter-annual variability of upper mesosphere temperatures, water vapor, and ice clouds, and also long term variations. We compare our model results with satellite borne and lidar observations including some record high NLC parameters measured in the summer season of 2009. The latitudinal dependence of trends and ice layer parameters is discussed, including a NH/SH comparison. We will present an explanation of the trends in the background atmosphere and ice layer parameters.

Long-Term Recovery of Life in the Chicxulub Crater

NASA Astrophysics Data System (ADS)

Lowery, C.; Jones, H.; Bralower, T. J.; Smit, J.; Rodriguez-Tovar, F. J.; Whalen, M. T.; Owens, J. D.; Expedition 364 Science Party, I. I.

2017-12-01

The Chicxulub Crater on the Yucatán Peninsula of Mexico was formed by the impact of an asteroid 66 Ma that caused the extinction of 75% of genera on Earth. Immediately following the impact, the decimated ecosystem began the long process of recovery, both in terms of primary productivity and species diversity. This well-documented process was heterogeneous across the world ocean, but until the present time it has been inaccessible at ground zero of the impact. IODP/ICDP Exp. 364 recovered 9.5 m of pelagic limestone spanning the entire Paleocene, including a continuous section spanning the first 5 myr following the impact. The Chicxulub Crater is the largest known marine impact crater on Earth, and the recovery of the ecosystem presented here is the first such record of long-term primary succession in the sterile zone of a large impact crater. Planktic and benthic foraminifera, calcareous nannoplankton, calcispheres, bioturbation, and geochemical proxies all indicate that export productivity in the Chicxulub Crater recovered rapidly (within 30 kyr) following the impact. Recovery in terms of diversity and species abundance took much longer, and varied between groups. Planktic foraminifera quickly diversified, with all common Paleocene tropical/subtropical species appearing roughly when expected. Trace fossils appear rapidly after the event, with a progressive recovery through the lowermost Paleocene. Calcareous nannoplankton took much longer to recover, and disaster taxa like Braarudosphaera dominated the assemblage well into the late Paleocene. Paleoecology and geochemistry relate these trends to oceanographic conditions within the Chicxulub Crater. Planktic foraminifera from known depth habitats, including Morozovellids, Acarininids, Chiloguembelinids, and Subbotinids, track changes in the water column structure and paleoredox conditions within the crater. Diverse and abundant macro- and microbenthic organisms indicate food availability and good oxygen conditions on the seafloor. The latest Paleocene, just prior to the onset of the PETM, is characterized by a typical and diverse assemblage of foraminifera and calcareous nannoplankton; a normal open-marine assemblage with no trace of long-term negative effects from the impact.

Uncertainty in detecting trend: a new criterion and its applications to global SST

NASA Astrophysics Data System (ADS)

Lian, Tao

2017-10-01

In most parts of the global ocean, the magnitude of the long-term linear trend in sea surface temperature (SST) is much smaller than the amplitude of multi-scale internal variation. One can thus use a specific period in a much longer record to arbitrarily determine the sign of long-term trend, which is statistically significant, in regional SST. This could lead to a controversial conclusion on how global SST responded to the anthropogenic forcing in the recent history. In this study, the uncertainty in the linear trend due to multi-scale internal variation is theoretically investigated. It is found that the "estimated" trend will not change its sign only when its magnitude is greater than a theoretical threshold that scales the influence from the multi-scale internal variation. Otherwise, the sign of the "estimated" trend may depend on the period used. The new criterion is found to be superior over the existing methods when the de-trended time series is dominated by the oscillatory term. Applying this new criterion to a global SST reconstruction from 1881 to 2013 reveals that the influences from multi-scale internal variation on the sign of "estimated" linear trend cannot be excluded in most parts of the Pacific, the southern Indian Ocean and the northern Atlantic; therefore, the warming or/and cooling trends found in these regions cannot be interpreted as the consequences of anthropogenic forcing. It's also suggested that the recent hiatus can be explained by combined uncertainty from internal variations at the interannual and decadal time scales.

Uncertainty in Detecting Trend: A New Criterion and Its Applications to Global SST

NASA Astrophysics Data System (ADS)

Lian, Tao

2017-04-01

In most parts of the global ocean, the magnitude of the long-term linear trend in sea surface temperature (SST) is much smaller than the amplitude of multi-scale internal variation. One can thus use a specific period in a much longer record to arbitrarily determine the sign of long-term trend, which is statistically significant, in regional SST. This could lead to a controversial conclusion on how global SST responded to the anthropogenic forcing in the recent history. In this study, the uncertainty in the linear trend due to multi-scale internal variation is theoretically investigated. It is found that the "estimated" trend will not change its sign only when its magnitude is greater than a theoretical threshold that scales the influence from the multi-scale internal variation. Otherwise, the sign of the "estimated" trend may depend on the period used. The new criterion is found to be superior over the existing methods when the de-trended time series is dominated by the oscillatory term. Applying this new criterion to a global SST reconstruction from 1881 to 2013 reveals that the influences from multi-scale internal variation on the sign of "estimated" linear trend cannot be excluded in most parts of the Pacific, the southern Indian Ocean and the northern Atlantic; therefore, the warming or/and cooling trends found in these regions cannot be interpreted as the consequences of anthropogenic forcing. It's also suggested that the recent hiatus can be explained by combined uncertainty from internal variations at the interannual and decadal time scales.

Cumulative effects of climate change and ice-wedge degradation, Prudhoe Bay oilfield Alaska

NASA Astrophysics Data System (ADS)

Walker, D. A.; Kanevskiy, M. Z.; Shur, Y.; Raynolds, M. K.; Buchhorn, M.

2016-12-01

Development of Arctic oil & gas resources requires extensive networks of roads, pipelines and other forms of infrastructure. The Prudhoe Bay Oilfield is the largest Arctic oilfield in North America with a long, well-documented history. In a previous publication we analyzed the historical record of high-resolution aerial photos to document the long-term changes to infrastructure extent (1949-2010) for the entire oilfield, and an integrated-geoecological-historical-change-mapping (IGHCM) approach to document terrain changes within 22-km2 areas of the oilfield. We reported the recent widespread expansion of thermokarst, starting in about 1989. Here we examine the annual air-photo record to better pinpoint the years of major change. We also conducted detailed field studies of roadside changes using topographic surveys and soil, vegetation and ice-wedge coring studies. Both sites exhibit extensive ice-wedge degradation that is caused by a combination of a long-term warming trend a series of exceptionally warm summers, and infrastructure-related factors that melted the tops of ice wedges. Near-road thermokarst is enhanced by warmer soils associated with road dust, roadside flooding, near-road pipelines, communication cables, and altered snow regimes. These strongly affect roadside ecosystems and the infrastructure itself. Changes to ecosystems include altered hydrology with the drying of polygon centers and the formation of well-developed high-centered polygons occurs in some areas. Other areas develop extensive flooding and erosion of ice-wedge troughs. An unexpected result of flooding is the stabilization of ice-wedge degradation in some areas because the increased productivity of sedges in the flooded areas is producing large amounts of organic material that protects the tops of ice wedges from further degradation. The large increases in productivity in roadside areas also attract large flocks of waterfowl. Changes to the soils with the addition of thick layers of dust cause decreases in the plant diversity. There are also broad social and economic implications. For example, a flood along the Dalton Highway in 2015 caused extensive degradation of ice wedges, major damage to the Dalton Highway and affected transportation to and from the oilfield for several weeks in Spring 2015.

Media Scrutiny of Higher Education: An Ongoing Challenge and Long-Term Trend

ERIC Educational Resources Information Center

Peyronel, Anthony C.

2004-01-01

Increasing skepticism was identified as a key trend in a recent American Journalism Review assessment of media coverage of higher education. However, this trend is hardly new, as American colleges and universities have been subjected to intense media scrutiny for at least the last two decades. This article examines the frequently adversarial…

NAEP Trends: Main NAEP vs. Long-Term Trend

ERIC Educational Resources Information Center

Beaton, Albert E.; Chromy, James R.

2010-01-01

The objectives of this research are to (a) compare the trend lines after some adjustments for level and scale only and determine if and how they differ; (b) describe the methodology of each assessment and identify similarities and differences; and (c) attempt to explain any observed differences based on comparable subsets or on special analysis.…

The browning of Alaska's boreal forest

Treesearch

Mary Beth Parent; David Verbyla

2010-01-01

We used twelve Landsat scenes from the 1980s-2009 and regional 2000-2009 MODIS data to examine the long-term trend in the normalized difference vegetation index (NDVI) within unburned areas of the Alaskan boreal forest. Our analysis shows that there has been a declining trend in NDVI in this region, with the strongest "browning trend" occurring in eastern...

ESTIMATES OF THE ATMOSPHERIC DEPOSITION OF SULFUR AND NITROGEN SPECIES: CLEAN AIR STATUS AND TRENDS NETWORK. 1990 THROUGH 2000

EPA Science Inventory

The Clean Air Status and Trends Network (CASTNet) was established by EPA in response to the requirements of the 1990 Clean Air Act Amendments. To satisfy these requirements CASTNet was designed to assess and report on geographic patterns and long-term, temporal trends in ambient ...

ITS logical architecture : traceability matrix.

DOT National Transportation Integrated Search

2003-11-01

This document provides information to aid in understanding and using the Long-Term Pavement Performance (LTPP) program pavement performance database. This document provides an introduction to the structure of the LTPP program, the relational structur...

Acidification of forest soil in Russia: From 1893 to present

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

Lapenis, A.G.; Lawrence, G.B.; Andreev, A.A.

2003-01-02

It is commonly believed that fine-textured soils developed on carbonate parent material are well buffered from possible acidification. There are no data, however, that document resistance of such soils to acidic deposition exposure on a timescale longer than 30-40 years. In this paper, we report on directly testing the long-term buffering capacity of nineteenth century forest soils developed on calcareous silt loam. In a chemical analysis comparing archived soils with modern soils collected from the same locations similar to 100 years later, we found varying degrees of forest-soil acidification in the taiga and forest steppe regions. Land-use history, increases inmore » precipitation, and acidic deposition were contributing factors in acidification. The acidification of forest soil was documented through decreases in soil pH and changes in concentrations of exchangeable calcium and aluminum, which corresponded with changes in communities of soil microfauna. Although acidification was found at all three analyzed locations, the trends in soil chemistry were most pronounced where the highest loading of acidic deposition had taken place.« less

Acidification of forest soil in Russia: From 1893 to present

USGS Publications Warehouse

Lapenis, A.G.; Lawrence, G.B.; Andreev, A.A.; Bobrov, A.A.; Torn, M.S.; Harden, J.W.

2004-01-01

It is commonly believed that fine-textured soils developed on carbonate parent material are well buffered from possible acidification. There are no data, however, that document resistance of such soils to acidic deposition exposure on a timescale longer than 30-40 years. In this paper, we report on directly testing the long-term buffering capacity of nineteenth century forest soils developed on calcareous silt loam. In a chemical analysis comparing archived soils with modern soils collected from the same locations ???100 years later, we found varying degrees of forest-soil acidification in the taiga and forest steppe regions. Land-use history, increases in precipitation, and acidic deposition were contributing factors in acidification. The acidification of forest soil was documented through decreases in soil pH and changes in concentrations of exchangeable calcium and aluminum, which corresponded with changes in communities of soil microfauna. Although acidification was found at all three analyzed locations, the trends in soil chemistry were most pronounced where the highest loading of acidic deposition had taken place. Copyright 2004 by the American Geophysical Union.

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

Sepanski, R.J.; Boden, T.A.; Daniels, R.C.

This document presents land-based monthly surface air temperature anomalies (departures from a 1951--1970 reference period mean) on a 5{degree} latitude by 10{degree} longitude global grid. Monthly surface air temperature anomalies (departures from a 1957--1975 reference period mean) for the Antarctic (grid points from 65{degree}S to 85{degree}S) are presented in a similar way as a separate data set. The data were derived primarily from the World Weather Records and the archives of the United Kingdom Meteorological Office. This long-term record of temperature anomalies may be used in studies addressing possible greenhouse-gas-induced climate changes. To date, the data have been employed inmore » generating regional, hemispheric, and global time series for determining whether recent (i.e., post-1900) warming trends have taken place. This document also presents the monthly mean temperature records for the individual stations that were used to generate the set of gridded anomalies. The periods of record vary by station. Northern Hemisphere station data have been corrected for inhomogeneities, while Southern Hemisphere data are presented in uncorrected form. 14 refs., 11 figs., 10 tabs.« less

Temporal changes in aquatic-invertebrate and fish assemblages in streams of the north-central and northeastern U.S.

USGS Publications Warehouse

Kennen, Jonathan G.; Sullivan, Daniel J.; May, Jason T.; Bell, Amanda H.; Beaulieu, Karen M.; Rice, Donald E.

2012-01-01

Many management agencies seek to evaluate temporal changes in aquatic assemblages at monitoring sites, but few have sites with ecological time series that are long enough for this purpose. Trends in aquatic-invertebrate and fish assemblage composition were assessed at 27 long-term monitoring sites in the north-central and northeastern United States. Temporal changes were identified using serial trend analysis. Sites with significant serial trends were further evaluated by relating explanatory environmental variables (e.g., streamflow, habitat, and water chemistry) to changes in assemblage composition. Significant trends were found at 19 of 27 study sites; however, differences in the sensitivity of the aquatic fauna to environmental stressors were identified. For example, significant trends in fish assemblages were found at more sites (15 of 27) than for aquatic-invertebrate assemblages (10 of 27 sites). In addition, trends in the invertebrate assemblage were most often explained by changes in streamflow processes (e.g., duration and magnitude of low- and high-flows, streamflow variability, and annual rates of change), whereas trends in the fish assemblage were more related to changes in water chemistry. Results illustrate the value of long-term monitoring for the purpose of assessing temporal trends in aquatic assemblages. The ability to detect trends in assemblage composition and to attribute these changes to environmental factors is necessary to understand mechanistic pathways and to further our understanding of how incremental anthropogenic alterations modify aquatic assemblages over time. Finally, this study's approach to trends analysis can be used to better inform the design of monitoring programs as well as support the ongoing management needs of stakeholders, water-resource agencies, and policy makers.

Families, Schools, and Major Demographic Trends in the United States

ERIC Educational Resources Information Center

Crosnoe, Robert; Benner, Aprile D.

2012-01-01

Although long-term social change is challenging to study, it is theoretically important because its effects are not immediate and it is not usually powered by major social institutions. Another challenge is that individuals are often only vaguely aware of long-term social changes and do not fully consider how they might be affected personally. As…

Long-term soil moisture patterns in a northern Minnesota forest

Treesearch

Salli F. Dymond; Randall K. Kolka; Paul V. Bolstad; Stephen D. Sebestyen

2014-01-01

Forest hydrological and biogeochemical processes are highly dependent on soil water. At the Marcell Experimental Forest, seasonal patterns of soil moisture have been monitored at three forested locations since 1966. This unique, long-term data set was used to analyze seasonal trends in soil moisture as well as the influence of time-lagged precipitation and modified...

Long-Term Pavement Performance Program: Pavement Performance Measures and Forecasting and the Effects of Maintenance and Rehabilitation Strategy on Treatment Effectiveness [Tech Brief

DOT National Transportation Integrated Search

2016-08-01

This document is a technical summary of the Federal Highway Administration Long-Term Pavement Performance Program report, Pavement Performance Measures and Forecasting and the Effects of Maintenance and Rehabilitation Strategy on Treatment Effectiven...

Future changes of interannual variation of the Asian summer monsoon precipitation using the CMIP5

NASA Astrophysics Data System (ADS)

Kamizawa, Nozomi; Takahashi, Hiroshi G.

2015-04-01

The Asian summer monsoon (ASM) region is one of the most populated areas in the world. Since the life of people who live in the region and the industry are strongly dependent on the ASM precipitation, it is interested that how it would change under the circumstance of global warming. Many studies have reported that the mean ASM precipitation would increase by comparing the CMIP models' climatology. Although the changes in mean climate are important, the long-term changes of interannual variability in precipitation are also significant. This study investigated the long-term trend of interannual precipitation variation over the ASM region by using 22 CMIP5 models. The RCP4.5 scenario was used. To investigate the long-term trend of the interannual variation of the ASM precipitation, each model data was recreated to 2.5 degree resolution and a running standard deviation for 21 years of June-July-August (JJA) precipitation were calculated. Next, we created the coefficient variation (CV) by dividing the running standard deviation by the mean JJA precipitation. Then we run a Mann-Kendall test for the CV at each grid. There were more areas which were indicated a statistically significant increasing trend than a decreasing trend in the ASM region. 40.6% of the region indicated an increasing trend in the future. On the other hand, 16.8% of the area was indicated to have a decreasing trend. It was also common in the global scale that the there were more areas that indicated an increasing trend than a decreasing trend. We also divided the area into three groups: land, shore and open ocean. In the ASM region, the shore areas particularly had an increasing CV trend. To investigate the long-term changes of the interannual variability of the precipitation and the atmospheric circulation over the ASM region, we conducted a composite analysis for the five wettest and driest years for two periods: the early 21st century (2007-2031) and the late 21st century (2076-2100). The special patterns of the interannual variation of the precipitation and the atmospheric circulation between the two periods had differed only slightly. A positive deviation precipitation band with a cyclonic circulation was recognized from across the Bay of Bengal to the equatorial Northwest Pacific. The none-big-difference of the patterns may suggest that interannual variation in the ASM region would increase not because the pattern changes, but because the pattern's strength gets stronger or its frequency gets higher.

Ozone time scale decomposition and trend assessment from surface observations

NASA Astrophysics Data System (ADS)

Boleti, Eirini; Hueglin, Christoph; Takahama, Satoshi

2017-04-01

Emissions of ozone precursors have been regulated in Europe since around 1990 with control measures primarily targeting to industries and traffic. In order to understand how these measures have affected air quality, it is now important to investigate concentrations of tropospheric ozone in different types of environments, based on their NOx burden, and in different geographic regions. In this study, we analyze high quality data sets for Switzerland (NABEL network) and whole Europe (AirBase) for the last 25 years to calculate long-term trends of ozone concentrations. A sophisticated time scale decomposition method, called the Ensemble Empirical Mode Decomposition (EEMD) (Huang,1998;Wu,2009), is used for decomposition of the different time scales of the variation of ozone, namely the long-term trend, seasonal and short-term variability. This allows subtraction of the seasonal pattern of ozone from the observations and estimation of long-term changes of ozone concentrations with lower uncertainty ranges compared to typical methodologies used. We observe that, despite the implementation of regulations, for most of the measurement sites ozone daily mean values have been increasing until around mid-2000s. Afterwards, we observe a decline or a leveling off in the concentrations; certainly a late effect of limitations in ozone precursor emissions. On the other hand, the peak ozone concentrations have been decreasing for almost all regions. The evolution in the trend exhibits some differences between the different types of measurement. In addition, ozone is known to be strongly affected by meteorology. In the applied approach, some of the meteorological effects are already captured by the seasonal signal and already removed in the de-seasonalized ozone time series. For adjustment of the influence of meteorology on the higher frequency ozone variation, a statistical approach based on Generalized Additive Models (GAM) (Hastie,1990;Wood,2006), which corrects for meteorological effects, has been developed in order to a) investigate if trends are masked by meteorological variability and b) to understand which part of the observed trends is meteorology driven. By correlating short-term variation of ozone, as obtained from the EEMD, with the corresponding short-term variation of relevant meteorological parameters, we subtract the variation of ozone concentrations that is related to the meteorological effects explained by the GAM. We find that higher frequency meteorological correction reduces further the uncertainty in trend estimation by a small factor. In addition, the seasonal variability of ozone as obtained from the EEMD has been studied in more detail for possible changes in its behavior. A shortening of the seasonal cycle was observed, i.e. reduction of maximum and in-crease of minimum concentration per year, while the occurrence of maximum is shifted to earlier times during a year. In summary, we present a sophisticated and consistent approach for detecting and categorizing trends and meteorological influences on ozone concentrations in long-term measurements across Europe.

Long-term precommercial thinning effects on Larix occidentalis (western larch) tree and stand characteristics

Treesearch

Michael S. Schaedel; Andrew J. Larson; David L. R. Affleck; R. Travis Belote; John M. Goodburn; David K. Wright; Elaine Kennedy Sutherland

2017-01-01

Precommercial thinning (PCT) is used to increase tree size and shorten harvest rotation time. Short-term results from PCT studies often show a trade-off between individual-tree growth and net stand yield, while longer-term effects of PCT on tree growth and stand yield are less well documented. We used a 54-year-old PCT study to test long-term effects of forest density...

Data Stewardship and Long-Term Archive of ICESat Data at the National Snow and Ice Data Center (NSIDC)

NASA Astrophysics Data System (ADS)

Fowler, D. K.; Moses, J. F.; Duerr, R. E.; Webster, D.; Korn, D.

2010-12-01

Data Stewardship is becoming a principal part of a data manager’s work at NSIDC. It is vitally important that our organization makes a commitment to both current and long-term goals of data management and the preservation of our scientific data. Data must be available to researchers not only during active missions, but long after missions end. This includes maintaining accurate documentation, data tools, and a knowledgeable user support staff. NSIDC is preparing for long-term support of the ICESat mission data. Though ICESat has seen its last operational day, the data is still being improved and NSIDC is scheduled to archive the final release, Release 33, starting late in 2010. This release will include the final adjustments to the processing algorithms and will produce the best possible products to date. Along with the higher-level data sets, all supporting documentation will be archived at NSIDC. For the long-term archive, it is imperative that there is sufficient information about how products were prepared in order to convince future researchers that the scientific results are reproducible. The processing algorithms along with the Level 0 and ancillary products used to create the higher-level products will be archived and made available to users. This can enable users to examine production history, to derive revised products and to create their own products. Also contained in the long-term archive will be pre-launch, calibration/validation, and test data. These data are an important part of the provenance which must be preserved. For longevity, we’ll need to archive the data and documentation in formats that will be supported in the years to come.

Climate effects on phytoplankton floral composition in Chesapeake Bay

NASA Astrophysics Data System (ADS)

Harding, L. W.; Adolf, J. E.; Mallonee, M. E.; Miller, W. D.; Gallegos, C. L.; Perry, E. S.; Johnson, J. M.; Sellner, K. G.; Paerl, H. W.

2015-09-01

Long-term data on floral composition of phytoplankton are presented to document seasonal and inter-annual variability in Chesapeake Bay related to climate effects on hydrology. Source data consist of the abundances of major taxonomic groups of phytoplankton derived from algal photopigments (1995-2004) and cell counts (1985-2007). Algal photopigments were measured by high-performance liquid chromatography (HPLC) and analyzed using the software CHEMTAX to determine the proportions of chlorophyll-a (chl-a) in major taxonomic groups. Cell counts determined microscopically provided species identifications, enumeration, and dimensions used to obtain proportions of cell volume (CV), plasma volume (PV), and carbon (C) in the same taxonomic groups. We drew upon these two independent data sets to take advantage of the unique strengths of each method, using comparable quantitative measures to express floral composition for the main stem bay. Spatial and temporal variability of floral composition was quantified using data aggregated by season, year, and salinity zone. Both time-series were sufficiently long to encompass the drought-flood cycle with commensurate effects on inputs of freshwater and solutes. Diatoms emerged as the predominant taxonomic group, with significant contributions by dinoflagellates, cryptophytes, and cyanobacteria, depending on salinity zone and season. Our analyses revealed increased abundance of diatoms in wet years compared to long-term average (LTA) or dry years. Results are presented in the context of long-term nutrient over-enrichment of the bay, punctuated by inter-annual variability of freshwater flow that strongly affects nutrient loading, chl-a, and floral composition. Statistical analyses generated flow-adjusted diatom abundance and showed significant trends late in the time series, suggesting current and future decreases of nutrient inputs may lead to a reduction of the proportion of biomass comprised by diatoms in an increasingly diverse flora.

Temporal trends in motor vehicle fatalities in the United States, 1968 to 2010 - a joinpoint regression analysis.

PubMed

Bandi, Priti; Silver, Diana; Mijanovich, Tod; Macinko, James

2015-12-01

In the past 40 years, a variety of factors might have impacted motor vehicle (MV) fatality trends in the US, including public health policies, engineering innovations, trauma care improvements, etc. These factors varied in their timing across states/localities, and many were targeted at particular population subgroups. In order to identify and quantify differential rates of change over time and differences in trend patterns between population subgroups, this study employed a novel analytic method to assess temporal trends in MV fatalities between 1968 and 2010, by age group and sex. Cause-specific MV fatality data from traffic injuries between 1968 and 2010, based on death certificates filed in the 50 states, and DC were obtained from Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research (CDC WONDER). Long-term (1968 to 2010) and short-term (log-linear piecewise segments) trends in fatality rates were compared for males and females overall and in four separate age groups using joinpoint regression. MV fatalities declined on average by 2.4% per year in males and 2.2% per year in females between 1968 and 2010, with significant declines observed in all age groups and in both sexes. In males overall and those 25 to 64 years, sharp declines between 1968 and mid-to-late 1990s were followed by a stalling until the mid-2000s, but rates in females experienced a long-term steady decline of a lesser magnitude than males during this time. Trends in those aged <1 to 14 years and 15 to 24 years were mostly steady over time, but males had a larger decline than females in the latter age group between 1968 and the mid-2000s. In ages 65+, short-term trends were similar between sexes. Despite significant long-term declines in MV fatalities, the application of Joinpoint Regression found that progress in young adult and middle-aged adult males stalled in recent decades and rates in males declined relatively more than in females in certain age groups. Future research is needed to establish the causes of these observed trends, including the potential role of contemporaneous MV-related policies and their repeal. Such research is needed in order to better inform the design and evaluation of future population interventions addressing MV fatalities nationally.

The Nation's Rivers

ERIC Educational Resources Information Center

Wolman, M. Gordon

1971-01-01

Illustrates difficulties in measuring long term changes in water temperature and content of dissolved oxygen, inorganic ions, radiation, pesticides, and trash and debris by reference to selected U. S. river systems. Concludes that observations to detect polluters may not provide data for assessing trends and trend reversals. (AL)

Atmospheric Chemistry Experiment (ACE) Measurements of Tropospheric and Stratospheric Chemistry and Long-Term Trends

NASA Technical Reports Server (NTRS)

Rinsland, Curtis P.; Bernath, Peter; Boone, Chris; Nassar, Ray

2007-01-01

We highlight chemistry and trend measurement results from the Atmospheric Chemistry Experiment (ACE) which is providing precise middle troposphere to the lower thermosphere measurements with a 0.02/cm resolution Fourier transform spectrometer covering 750-4400/cm

Analysis and prediction of rainfall trends over Bangladesh using Mann-Kendall, Spearman's rho tests and ARIMA model

NASA Astrophysics Data System (ADS)

Rahman, Mohammad Atiqur; Yunsheng, Lou; Sultana, Nahid

2017-08-01

In this study, 60-year monthly rainfall data of Bangladesh were analysed to detect trends. Modified Mann-Kendall, Spearman's rho tests and Sen's slope estimators were applied to find the long-term annual, dry season and monthly trends. Sequential Mann-Kendall analysis was applied to detect the potential trend turning points. Spatial variations of the trends were examined using inverse distance weighting (IDW) interpolation. AutoRegressive integrated moving average (ARIMA) model was used for the country mean rainfall and for other two stations data which depicted the highest and the lowest trend in the Mann-Kendall and Spearman's rho tests. Results showed that there is no significant trend in annual rainfall pattern except increasing trends for Cox's Bazar, Khulna, Satkhira and decreasing trend for Srimagal areas. For the dry season, only Bogra area represented significant decreasing trend. Long-term monthly trends demonstrated a mixed pattern; both negative and positive changes were found from February to September. Comilla area showed a significant decreasing trend for consecutive 3 months while Rangpur and Khulna stations confirmed the significant rising trends for three different months in month-wise trends analysis. Rangpur station data gave a maximum increasing trend in April whereas a maximum decreasing trend was found in August for Comilla station. ARIMA models predict +3.26, +8.6 and -2.30 mm rainfall per year for the country, Cox's Bazar and Srimangal areas, respectively. However, all the test results and predictions revealed a good agreement among them in the study.

Generalized water-level contours, September-October 2000 and March-April 2001, and long-term water-level changes, at the U.S. Air Force Plant 42 and vicinity, Palmdale, California

USGS Publications Warehouse

Christensen, Allen H.

2005-01-01

Historically, the U.S. Air Force Plant 42 has relied on ground water as the primary source of water owing, in large part, to the scarcity of surface water in the region. Groundwater withdrawal for municipal, industrial, and agricultural use has affected ground-water levels at U.S. Air Force Plant 42, and vicinity. A study to document changes in groundwater gradients and to present historical water-level data was completed by the U.S. Geological Survey in cooperation with the U.S. Air Force. This report presents historical water-level data, hydrographs, and generalized seasonal water-level and water-level contours for September?October 2000 and March?April 2001. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water flow systems, and consequently water availability. During September?October 2000 and March?April 2001 the U.S. Geological Survey and other agencies made a total of 102 water-level measurements, 46 during September?October 2000 and 56 during March?April 2001. These data document recent conditions and, when compared with historical data, document changes in ground-water levels. Two water-level contour maps were drawn: the first depicts water-level conditions for September?October 2000 map and the second depicts water-level conditions for March?April 2001 map. In general, the water-level contour maps show water-level depressions formed as result of ground-water withdrawal. One hundred sixteen long-term hydrographs, using water-level data from 1915 through 2000, were constructed to show water-level trends in the area. The hydrographs indicate that water-level decline occurred throughout the study area, with the greatest declines south of U.S. Air Force Plant 42.

Statistical significance of seasonal warming/cooling trends

NASA Astrophysics Data System (ADS)

Ludescher, Josef; Bunde, Armin; Schellnhuber, Hans Joachim

2017-04-01

The question whether a seasonal climate trend (e.g., the increase of summer temperatures in Antarctica in the last decades) is of anthropogenic or natural origin is of great importance for mitigation and adaption measures alike. The conventional significance analysis assumes that (i) the seasonal climate trends can be quantified by linear regression, (ii) the different seasonal records can be treated as independent records, and (iii) the persistence in each of these seasonal records can be characterized by short-term memory described by an autoregressive process of first order. Here we show that assumption ii is not valid, due to strong intraannual correlations by which different seasons are correlated. We also show that, even in the absence of correlations, for Gaussian white noise, the conventional analysis leads to a strong overestimation of the significance of the seasonal trends, because multiple testing has not been taken into account. In addition, when the data exhibit long-term memory (which is the case in most climate records), assumption iii leads to a further overestimation of the trend significance. Combining Monte Carlo simulations with the Holm-Bonferroni method, we demonstrate how to obtain reliable estimates of the significance of the seasonal climate trends in long-term correlated records. For an illustration, we apply our method to representative temperature records from West Antarctica, which is one of the fastest-warming places on Earth and belongs to the crucial tipping elements in the Earth system.

The long-term changes in total ozone, as derived from Dobson measurements at Arosa (1948-2001)

NASA Astrophysics Data System (ADS)

Krzyscin, J. W.

2003-04-01

The longest possible total ozone time series (Arosa, Switzerland) is examined for a detection of trends. Two-step procedure is proposed to estimate the long-term (decadal) variations in the ozone time series. The first step consists of a standard least-squares multiple regression applied to the total ozone monthly means to parameterize "natural" (related to the oscillations in the atmospheric dynamics) variations in the analyzed time series. The standard proxies for the dynamical ozone variations are used including; the 11-year solar activity cycle, and indices of QBO, ENSO and NAO. We use the detrended time series of temperature at 100 hPa and 500 hPa over Arosa to parameterize short-term variations (with time periods<1 year) in total ozone related to local changes in the meteorological conditions over the station. The second step consists of a smooth-curve fitting to the total ozone residuals (original minus modeled "natural" time series), the time derivation applied to this curve to obtain local trends, and bootstrapping of the residual time series to estimate the standard error of local trends. Locally weighted regression and the wavelet analysis methodology are used to extract the smooth component out of the residual time series. The time integral over the local trend values provides the cumulative long-term change since the data beginning. Examining the pattern of the cumulative change we see the periods with total ozone loss (the end of 50s up to early 60s - probably the effect of the nuclear bomb tests), recovery (mid 60s up to beginning of 70s), apparent decrease (beginning of 70s lasting to mid 90s - probably the effect of the atmosphere contamination by anthropogenic substances containing chlorine), and with a kind of stabilization or recovery (starting in the mid of 90s - probably the effect of the Montreal protocol to eliminate substances reducing the ozone layer). We can also estimate that a full ozone recovery (return to the undisturbed total ozone level from the beginning of 70s) is expected around 2050. We propose to calculate both time series of local trends and the cumulative long-term change instead single trend value derived as a slope of straight line fit to the data.

Is Privately Funded Research on the Rise in Ocean Science?

NASA Astrophysics Data System (ADS)

Spring, M.; Cooksey, S. W.; Orcutt, J. A.; Ramberg, S. E.; Jankowski, J. E.; Mengelt, C.

2014-12-01

While federal funding for oceanography is leveling off or declining, private sector funding from industry and philanthropy appears to be on the rise. The Ocean Studies Board of the National Research Council is discussing these changes in the ocean science funding landscape. In 2014 the Board convened experts to better understand the long term public and private funding trends for the ocean sciences and the implications of such trends for the ocean science enterprise and the nation. Specific topics of discussion included: (1) the current scope of philanthropic and industry funding for the ocean sciences; (2) the long-term trends in the funding balance between federal and other sources of funding; (3) the priorities and goals for private funders; and (4) the characteristics of various modes of engagement for private funders. Although public funding remains the dominant source of research funding, it is unclear how far or fast that balance might shift in the future nor what a shifting balance may mean. There has been no comprehensive assessment of the magnitude and impact of privately-funded science, particularly the ocean sciences, as public funding sources decline. Nevertheless, the existing data can shed some light on these questions. We will present available data on long-term trends in federal and other sources of funding for science (focusing on ocean science) and report on preliminary findings from a panel discussion with key private foundations and industry funders.

Salting our freshwater lakes.

PubMed

Dugan, Hilary A; Bartlett, Sarah L; Burke, Samantha M; Doubek, Jonathan P; Krivak-Tetley, Flora E; Skaff, Nicholas K; Summers, Jamie C; Farrell, Kaitlin J; McCullough, Ian M; Morales-Williams, Ana M; Roberts, Derek C; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C; Weathers, Kathleen C

2017-04-25

The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L -1 ), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue.

Long-term ground deformation patterns of Bucharest using multi-temporal InSAR and multivariate dynamic analyses: a possible transpressional system?

PubMed Central

Armaş, Iuliana; Mendes, Diana A.; Popa, Răzvan-Gabriel; Gheorghe, Mihaela; Popovici, Diana

2017-01-01

The aim of this exploratory research is to capture spatial evolution patterns in the Bucharest metropolitan area using sets of single polarised synthetic aperture radar (SAR) satellite data and multi-temporal radar interferometry. Three sets of SAR data acquired during the years 1992–2010 from ERS-1/-2 and ENVISAT, and 2011–2014 from TerraSAR-X satellites were used in conjunction with the Small Baseline Subset (SBAS) and persistent scatterers (PS) high-resolution multi-temporal interferometry (InSAR) techniques to provide maps of line-of-sight displacements. The satellite-based remote sensing results were combined with results derived from classical methodologies (i.e., diachronic cartography) and field research to study possible trends in developments over former clay pits, landfill excavation sites, and industrial parks. The ground displacement trend patterns were analysed using several linear and nonlinear models, and techniques. Trends based on the estimated ground displacement are characterised by long-term memory, indicated by low noise Hurst exponents, which in the long-term form interesting attractors. We hypothesize these attractors to be tectonic stress fields generated by transpressional movements. PMID:28252103

Long-term ground deformation patterns of Bucharest using multi-temporal InSAR and multivariate dynamic analyses: a possible transpressional system?

PubMed

Armaş, Iuliana; Mendes, Diana A; Popa, Răzvan-Gabriel; Gheorghe, Mihaela; Popovici, Diana

2017-03-02

The aim of this exploratory research is to capture spatial evolution patterns in the Bucharest metropolitan area using sets of single polarised synthetic aperture radar (SAR) satellite data and multi-temporal radar interferometry. Three sets of SAR data acquired during the years 1992-2010 from ERS-1/-2 and ENVISAT, and 2011-2014 from TerraSAR-X satellites were used in conjunction with the Small Baseline Subset (SBAS) and persistent scatterers (PS) high-resolution multi-temporal interferometry (InSAR) techniques to provide maps of line-of-sight displacements. The satellite-based remote sensing results were combined with results derived from classical methodologies (i.e., diachronic cartography) and field research to study possible trends in developments over former clay pits, landfill excavation sites, and industrial parks. The ground displacement trend patterns were analysed using several linear and nonlinear models, and techniques. Trends based on the estimated ground displacement are characterised by long-term memory, indicated by low noise Hurst exponents, which in the long-term form interesting attractors. We hypothesize these attractors to be tectonic stress fields generated by transpressional movements.

Temperature and ice layer trends in the summer middle atmosphere

NASA Astrophysics Data System (ADS)

Lübken, F.-J.; Berger, U.

2012-04-01

We present results from our LIMA model (Leibniz Institute Middle Atmosphere Model) which nicely reproduces mean conditions of the summer mesopause region and also mean characteristics of ice layers known as noctilucent clouds. LIMA nudges to ECMWF data in the troposphere and lower stratosphere which influences the background conditions in the mesosphere. We study temperature trends in the mesosphere at middle and polar latitudes and compared with temperature trends from satellites, lidar, and phase height observations. For the first time large observed temperature trends in the summer mesosphere can be reproduced and explained by a model. As will be shown, stratospheric ozone has a major impact on temperature trends in the summer mesosphere. The temperature trend is not uniform in time: it is moderate from 1961 (the beginning of our record) until the beginning of the 1980s. Thereafter, temperatures decrease much stronger until the mid 1990s. Thereafter, temperatures are nearly constant or even increase with time. As will be shown, trends in ozone and carbon dioxide explain most of this behavior. Ice layers in the summer mesosphere are very sensitive to background conditions and are therefore considered to be appropriate tracers for long term variations in the middle atmosphere. We use LIMA background conditions to determine ice layer characteristics in the mesopause region. We compare our results with measurements, for example with albedos from the SBUV satellites, and show that we can nicely reproduce observed trends. It turns out that temperature trends are positive (negative) in the upper (lower) part of the ice layer regime. This complicates an interpretation of NLC long term variations in terms of temperature trends.

Long-Term Trends in Hematological and Nutritional Status After Gastrectomy for Gastric Cancer.

PubMed

Kim, Ji-Hyun; Bae, You-Jin; Jun, Kyong-Hwa; Chin, Hyung-Min

2017-08-01

This study investigated long-term trends in hematological and nutritional parameters after gastrectomy for gastric cancer and evaluated the influence of the reconstruction type on these trends. The medical records of 558 patients who underwent curative gastrectomy with standard lymph node dissection for stage I gastric cancer between January 2006 and December 2013 were reviewed. The hematological and nutritional parameters evaluated included hemoglobin, ferritin, vitamin B 12 , total protein, albumin, total cholesterol, triglyceride, and calcium. The patients were followed up for 6 months postoperatively and then annually until death, cancer recurrence, or follow-up loss. In the long term, ferritin and triglyceride gradually decreased after gastrectomy, while the other parameters decreased slightly or were stable. In the comparisons according to reconstruction type, the Roux-en-Y group had the lowest levels of hemoglobin, ferritin, vitamin B12, total protein, albumin, and total cholesterol beginning 6 months postoperatively compared with the Billroth I and II groups. However, only ferritin and vitamin B 12 had significant differences in the 5-year cumulative incidences of deficiency/reduction according to the reconstruction type, whereas albumin, triglyceride, total cholesterol, and calcium did not. Although malabsorption and malnutrition are common in patients after a gastrectomy, most nutritional parameters were stable or decreased slightly in the long-term and were not markedly influenced by the reconstruction type or extent of gastrectomy. Therefore, for more accurate nutritional assessment after gastrectomy, multidirectional monitoring should be considered rather than simply measuring biochemical parameters.

Trends and variations of pH and hardness in a typical semi-arid river in a monsoon climate region during 1985-2009.

PubMed

Hao, Shaonan; Li, Xuyong; Jiang, Yan; Zhao, Hongtao; Yang, Lei

2016-09-01

The rapid growth of urbanization and industrialization, along with dramatic climate change, has strongly influenced hydrochemical characteristics in recent decades in China and thus could cause the variation of pH and general total hardness of a river. To explore such variations and their potential influencing factors in a river of the monsoon climate region, we analyzed a long-term monitoring dataset of pH, SO4 (2-), NOx, general total hardness (GH), Mg(2+), Ca(2+), and Cl(-) in surface water and groundwater in the Luan River basin from 1985 to 2009. The nonparametric Seasonal Kendall trend test was used to test the long-term trends of pH and GH. Relationship between the affecting factors, pH and GH were discussed. Results showed that pH showed a decreasing trend and that GH had an increasing trend in the long-term. Seasonal variation of pH and GH was mainly due to the typical monsoon climate. Results of correlation analysis showed that the unit area usage amounts of chemical fertilizer, NO3 (-), and SO4 (2-) were negatively correlated with pH in groundwater. In addition, mining activity affected GH spatial variation. Acid deposition, drought, and increasing the use of chemical fertilizers would contribute to the acidification trend, and mining activities would affect the spatial variation of GH. Variations of precipitation and runoff in semi-arid monsoon climate areas had significant influences on the pH and GH. Our findings implied that human activities played a critical role in river acidification in the semi-arid monsoon climate region of northern China.

Incidence and mortality trends of aspiration pneumonia in Parkinson's disease in the United States, 1979-2010.

PubMed

Akbar, Umer; Dham, Bhavpreet; He, Ying; Hack, Nawaz; Wu, Samuel; Troche, Michelle; Tighe, Patrick; Nelson, Eugene; Friedman, Joseph H; Okun, Michael S

2015-09-01

Careful examination of long-term analyses and trends is essential in understanding the medico-economic burden of this common complication. We sought to describe the long-term (32-year) trends of incidence and mortality in PD patients hospitalized with aspiration pneumonia (AsPNA). Incidence and mortality of AsPNA in hospitalized PD versus non-PD patients was assessed by logistic regression analysis applied to a national database between the years 1979 and 2010. Covariates such as age-decennium, gender, year AsPNA occurred, and the interactions with PD diagnosis were investigated. Rate of AsPNA and mortality over the 32-years was trended and compared. AsPNA occurred in 3.6% of PD patients and 1.0% of non-PD patients. The average mortality for PD patients was less (17% vs. 22%). Long-term (32-year) trends revealed a nearly 10-fold increase in incidence of AsPNA in PD (0.4% in 1979, 4.9% in 2010), decreasing mortality overtime, higher likelihood in males, and increasing average age of AsPNA patients (steeper increase in PD). All p-values<0.05. In regression analysis, each successive year had a slight increase in odds of AsPNA (OR 1.03 in PD, OR1.06 in non-PD). Trends over 32 years revealed a 10-fold increase in AsPNA among PD and non-PD patients, and an associated decrease in mortality. Our data suggest that PD patients are living longer, have slightly more AsPNA, but a lower mortality than was seen in past decades. Further research should investigate the causes of AsPNA in PD, and also potential interventions to decrease its occurrence. Copyright © 2015 Elsevier Ltd. All rights reserved.

Firearm homicide in Australia, Canada, and New Zealand: what can we learn from long-term international comparisons?

PubMed

McPhedran, Samara; Baker, Jeanine; Singh, Pooja

2011-01-01

Although firearm homicide remains a topic of interest within criminological and policy discourse, existing research does not generally undertake longitudinal comparisons between countries. However, cross-country comparisons provide insight into whether "local" trends (e.g., declines in firearm homicide in one particular country) differ from broader, international trends. This in turn can improve knowledge about the role of factors such as policing practices and socioeconomic variables in the incidence of lethal violence using firearms. The current study compares long-term firearm homicide trends in three countries with similar social histories but different legislative regimes: Australia, Canada, and New Zealand. Using negative binomial regression, the study found that the most pronounced decline in firearm homicide over the past two decades occurred in New Zealand. Connections between social disadvantage, policing policy, and violence are discussed.

Analysis of long-term trends (1950–2009) in precipitation, runoff and runoff coefficient in major urban watersheds in the United States

USGS Publications Warehouse

Velpuri, N.M.; Senay, G.B.

2013-01-01

This study investigates the long-term trends in precipitation, runoff and runoff coefficient in major urban watersheds in the United States. The seasonal Mann–Kendall trend test was performed on monthly precipitation, runoff and runoff coefficient data from 1950 to 2009 obtained from 62 urban watersheds covering 21 major urban centers in the United States. The results indicate that only five out of 21 urban centers in the United States showed an uptrend in precipitation. Twelve urban centers showed an uptrend in runoff coefficient. However, six urban centers did not show any trend in runoff coefficient, and three urban centers showed a significant downtrend. The highest rate of change in precipitation, runoff and runoff coefficient was observed in the Houston urban watershed. Based on the results obtained, we also attributed plausible causes for the trends. Our analysis indicated that while a human only influence is observed in most of the urban watersheds, a combined climate and human influence is observed in the central United States.

Trend and recovery of the total ozone column in South America and Antarctica

NASA Astrophysics Data System (ADS)

Toro A., Richard; Araya, Consuelo; Labra O., Felipe; Morales, Luis; Morales, Raúl G. E.; Leiva G., Manuel A.

2017-12-01

South America is one of the most vulnerable areas to stratospheric ozone depletion; consequently, an increased amount of UV radiation reaches the Earth's surface in this region. In this study, we analyzed the long-term trend in the total ozone column (TOC) over the southern part of the South American continent from 1980 to 2009. The database used was obtained by combining several satellite measurements of the TOC on a 1° (latitude) × 1.25° (longitude) grid. Analysis of the long-term trend was performed by applying the Theil-Sen estimator and the Mann-Kendall significance test to the deseasonalized time series. The long-term trend was also analyzed over several highly populated urban zones in the study area. Finally, multiple linear regression (MLR) modeling was used to identify and quantify the drivers of interannual variability in the TOC over the study area with a pixel-by-pixel approach. The results showed a decrease in the TOC ranging from -0.3 to -4% dec-1 from 1980 to 2009. On a decadal timescale, there is significant variability in this trend, and a decrease of more than -10% dec-1 was found at high latitudes (1980-1989). However, the trends obtained over much of the study area were not statistically significant. Considering the period from 1980 to 1995, we found a decrease in the TOC of -2.0 ± 0.6% dec-1 at latitudes below 40° S and -6.9 ± 2.0% dec-1 at latitudes above 40° S, for a 99.9% confidence level over most of the study area. Analysis of the period from 1996 to 2009 showed a statistically significant increase of 2.3 ± 0.1% dec-1 at high latitudes (> 60° S), confirming the initial TOC recovery in the Antarctic. Despite evidence for initial recovery of the TOC in some parts of the study area between 1996 and 2009, the long-term increase from September to November is not yet statistically significant. In addition, large parts of the study area and most of the urban areas continue to show a decreasing trend in the TOC. The MLR results show that at high latitudes, the main driver of interannual variability in the TOC is the total effective amount of halogens, followed by the eddy heat flux.

Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA great plains: Part II. Temporal trends

NASA Astrophysics Data System (ADS)

Kukal, M.; Irmak, S.

2016-11-01

Detection of long-term changes in climate variables over large spatial scales is a very important prerequisite to the development of effective mitigation and adaptation measures for the future potential climate change and for developing strategies for future hydrologic balance analyses under changing climate. Moreover, there is a need for effective approaches of providing information about these changes to decision makers, water managers and stakeholders to aid in efficient implementation of the developed strategies. This study involves computation, mapping and analyses of long-term (1968-2013) county-specific trends in annual, growing-season (1st May-30th September) and monthly air temperatures [(maximum (Tmax), minimum (Tmin) and average (Tavg)], daily temperature range (DTR), precipitation, grass reference evapotranspiration (ETo) and aridity index (AI) over the USA Great Plains region using datasets from over 800 weather station sites. Positive trends in annual Tavg, Tmax and Tmin, DTR, precipitation, ETo and AI were observed in 71%, 89%, 85%, 31%, 61%, 38% and 66% of the counties in the region, respectively, whereas these proportions were 48%, 89%, 62%, 20%, 57%, 28%, and 63%, respectively, for the growing-season averages of the same variables. On a regional average basis, the positive trends in growing-season Tavg, Tmax and Tmin, DTR, precipitation, ETo and AI were 0.18 °C decade-1, 0.19 °C decade-1, 0.17 °C decade-1, 0.09 °C decade-1, 1.12 mm yr-1, 0.4 mm yr-1 and 0.02 decade-1, respectively, and the negative trends were 0.21 °C decade-1, 0.06 °C decade-1, 0.09 °C decade-1, 0.22 °C decade-1, 1.16 mm yr-1, 0.76 mm yr-1 and 0.02 decade-1, respectively. The temporal trends were highly variable in space and were appropriately represented using monthly, annual and growing-season maps developed using Geographic Information System (GIS) techniques. The long-term and spatial and temporal information and data for a large region provided in this study can be used to analyze county-level trends in important climatic/hydrologic variables in context of climate change, water resources, agricultural and natural resources response to climate change.

Nutrient concentrations and loads in the northeastern United States - Status and trends, 1975-2003

USGS Publications Warehouse

Trench, Elaine C. Todd; Moore, Richard B.; Ahearn, Elizabeth A.; Mullaney, John R.; Hickman, R. Edward; Schwarz, Gregory E.

2012-01-01

The U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) began regional studies in 2003 to synthesize information on nutrient concentrations, trends, stream loads, and sources. In the northeastern United States, a study area that extends from Maine to central Virginia, nutrient data were evaluated for 130 USGS water-quality monitoring stations. Nutrient data were analyzed for trends in flow-adjusted concentrations, modeled instream (non-flow-adjusted) concentrations, and stream loads for 32 stations with 22 to 29 years of water-quality and daily mean streamflow record during 1975-2003 (termed the long-term period), and for 46 stations during 1993-2003 (termed the recent period), by using a coupled statistical model of streamflow and water quality developed by the USGS. Recent trends in flow-adjusted concentrations of one or more nutrients also were analyzed for 90 stations by using Tobit regression. Annual stream nutrient loads were estimated, and annual nutrient yields were calculated, for 47 stations for the long-term and recent periods, and for 37 additional stations that did not have a complete streamflow and water-quality record for 1993-2003. Nutrient yield information was incorporated for 9 drainage basins evaluated in a national NAWQA study, for a total of 93 stations evaluated for nutrient yields. Long-term downward trends in flow-adjusted concentrations of total nitrogen and total phosphorus (18 and 19 of 32 stations, respectively) indicate regional improvements in nutrient-related water-quality conditions. Most of the recent trends detected for total phosphorus were upward (17 of 83 stations), indicating possible reversals to the long-term improvements. Concentrations of nutrients in many streams persist at levels that are likely to affect aquatic habitat adversely and promote freshwater or coastal eutrophication. Recent trends for modeled instream concentrations, and modeled reference concentrations, were evaluated relative to ecoregion-based nutrient criteria proposed by the U.S. Environmental Protection Agency. Instream concentrations of total nitrogen and total phosphorus persist at levels higher than proposed criteria at more than one-third and about one-half, respectively, of the 46 stations analyzed. Long-term trends in nutrient loads were primarily downward, with downward trends in total nitrogen and total phosphorus loads detected at 12 and 17 of 32 stations, respectively. Upward trends were rare, with one upward trend for total nitrogen loads and none for total phosphorus. Trends in loads of nitrite-plus-nitrate nitrogen included 7 upward and 8 downward trends among 32 stations. Downward trends in loads of ammonia nitrogen and total Kjeldahl nitrogen were detected at all six stations evaluated. Long-term downward trends detected in four of the five largest drainage basins evaluated include: total nitrogen loads for the Connecticut, Delaware, and James Rivers; total Kjeldahl nitrogen and ammonia nitrogen loads for the Susquehanna River; ammonia nitrogen and nitrite-plus-nitrate nitrogen loads for the James River; and total phosphorus loads for the Connecticut and Delaware Rivers. No trends in load were detected for the Potomac River. Nutrient yields were evaluated relative to the extent of land development in 93 drainage basins. The undeveloped land-use category included forested drainage basins with undeveloped land ranging from 75 to 100 percent of basin area. Median total nitrogen yields for the 27 undeveloped drainage basins evaluated, including 9 basins evaluated in a national NAWQA study, ranged from 290 to 4,800 pounds per square mile per year (lb/mi2/yr). Total nitrogen yields even in the most pristine drainage basins may be elevated relative to natural conditions, because of high rates of atmospheric deposition of nitrogen in parts of the northeastern United States. Median total phosphorus yields ranged from 12 to 330 lb/mi2/yr for the 26 undeveloped basins evaluated. The undeveloped category includes some large drainage basins with point-source discharges and small percentages of developed land; in these basins, streamflow from undeveloped headwater areas dilutes streamflow in more urbanized reaches, and dampens but does not eliminate the point-source "signal" of higher nutrient loads. Median total nitrogen yields generally do not exceed 1,700 lb/mi2/yr, and median total phosphorus yields generally do not exceed 100 lb/mi2/yr, in the drainage basins that are least affected by human land-use and waste-disposal practices. Agricultural and urban land use has increased nutrient yields substantially relative to undeveloped drainage basins. Median total nitrogen yields for 24 agricultural basins ranged from 1,700 to 26,000 lb/mi2/yr, and median total phosphorus yields ranged from 94 to 1,000 lb/mi2/yr. The maximum estimated total nitrogen and total phosphorus yields, 32,000 and 16,000 lb/mi2/yr, respectively, for all stations in the region were in small (less than 50 square miles (mi2)) agricultural drainage basins. Median total nitrogen yields ranged from 1,400 to 17,000 lb/mi2/yr in 26 urbanized drainage basins, and median total phosphorus yields ranged from 43 to 1,900 lb/mi2/yr. Urbanized drainage basins with the highest nutrient yields are generally small (less than 300 mi2) and are drained by streams that receive major point-source discharges. Instream nutrient loads were evaluated relative to loads from point-source discharges in four drainage basins: the Quinebaug River Basin in Connecticut, Massachusetts, and Rhode Island; the Raritan River Basin in New Jersey; the Patuxent River Basin in Maryland; and the James River Basin in Virginia. Long-term downward trends in nutrient loads, coupled with similar trends in flow-adjusted nutrient concentrations, indicate long-term reductions in the delivery of most nutrients to these streams. However, the absence of recent downward trends in load for most nutrients, coupled with instream concentrations that exceed proposed nutrient criteria in several of these waste-receiving streams, indicates that challenges remain in reducing delivery of nutrients to streams from point sources. During dry years, the total nutrient load from point sources in some of the drainage basins approached or equaled the nutrient load transported by the stream.

Quantifiable long-term monitoring on parks and nature preserves

USGS Publications Warehouse

Beck, Scott; Moorman, Christopher; DePerno, Christopher S.; Simons, Theodore R.

2013-01-01

Herpetofauna have declined globally, and monitoring is a useful approach to document local and long-term changes. However, monitoring efforts often fail to account for detectability or follow standardized protocols. We performed a case study at Hemlock Bluffs Nature Preserve in Cary, NC to model occupancy of focal species and demonstrate a replicable long-term protocol useful to parks and nature preserves. From March 2010 to 2011, we documented occupancy of Ambystoma opacum(Marbled Salamander), Plethodon cinereus (Red-backed Salamander), Carphophis amoenus (Eastern Worm Snake), and Diadophis punctatus (Ringneck Snake) at coverboard sites and estimated breeding female Ambystoma maculatum (Spotted Salamander) abundance via dependent double-observer egg-mass counts in ephemeral pools. Temperature influenced detection of both Marbled and Red-backed Salamanders. Based on egg-mass data, we estimated Spotted Salamander abundance to be between 21 and 44 breeding females. We detected 43 of 53 previously documented herpetofauna species. Our approach demonstrates a monitoring protocol that accounts for factors that influence species detection and is replicable by parks or nature preserves with limited resources.

Tennessee long-range transportation plan : modal needs

DOT National Transportation Integrated Search

2005-12-01

This report documents one of several major steps in the long-range planning process. This report examines each component of the states transportation network to identify the long-term needs of the transportation modes to 2030. The determination of...

Long-Term Trends in Private School Enrollments by Family Income. CEPA Working Paper No. 17-07

ERIC Educational Resources Information Center

Murnane, Richard J.; Reardon, Sean F.

2017-01-01

We use data from multiple national surveys to describe trends in private elementary school enrollment by family income from 1968-2013. We note several important trends. First, the private school enrollment rate of middle-income families declined substantially over the last five decades, while that of high-income families remained quite stable.…

Pulling Apart: A State-by-State Analysis of Income Trends.

ERIC Educational Resources Information Center

Bernstein, Jared; McNichol, Elizabeth C.; Mishel, Lawrence; Zahradnik, Robert

This report examines trends in income distribution from the late 1970s to the late 1990s in the 50 states. It is based on before-tax income for families from the Census Bureau's March Current Population Survey public use files. All figures are expressed in 1997 dollars and adjusted for inflation. The paper examines the long term trend from the…

Estimating trends in the global mean temperature record

NASA Astrophysics Data System (ADS)

Poppick, Andrew; Moyer, Elisabeth J.; Stein, Michael L.

2017-06-01

Given uncertainties in physical theory and numerical climate simulations, the historical temperature record is often used as a source of empirical information about climate change. Many historical trend analyses appear to de-emphasize physical and statistical assumptions: examples include regression models that treat time rather than radiative forcing as the relevant covariate, and time series methods that account for internal variability in nonparametric rather than parametric ways. However, given a limited data record and the presence of internal variability, estimating radiatively forced temperature trends in the historical record necessarily requires some assumptions. Ostensibly empirical methods can also involve an inherent conflict in assumptions: they require data records that are short enough for naive trend models to be applicable, but long enough for long-timescale internal variability to be accounted for. In the context of global mean temperatures, empirical methods that appear to de-emphasize assumptions can therefore produce misleading inferences, because the trend over the twentieth century is complex and the scale of temporal correlation is long relative to the length of the data record. We illustrate here how a simple but physically motivated trend model can provide better-fitting and more broadly applicable trend estimates and can allow for a wider array of questions to be addressed. In particular, the model allows one to distinguish, within a single statistical framework, between uncertainties in the shorter-term vs. longer-term response to radiative forcing, with implications not only on historical trends but also on uncertainties in future projections. We also investigate the consequence on inferred uncertainties of the choice of a statistical description of internal variability. While nonparametric methods may seem to avoid making explicit assumptions, we demonstrate how even misspecified parametric statistical methods, if attuned to the important characteristics of internal variability, can result in more accurate uncertainty statements about trends.

Farming Approaches for Greater Biodiversity, Livelihoods, and Food Security.

PubMed

Garibaldi, Lucas A; Gemmill-Herren, Barbara; D'Annolfo, Raffaele; Graeub, Benjamin E; Cunningham, Saul A; Breeze, Tom D

2017-01-01

Scientists and policy-makers globally are calling for alternative approaches to conventional intensification of agriculture that enhance ecosystem services provided by biodiversity. The evidence reviewed here suggests that alternative approaches can achieve high crop yields and profits, but the performance of other socioeconomic indicators (as well as long-term trends) is surprisingly poorly documented. Consequently, the implementation of conventional intensification and the discussion of alternative approaches are not based on quantitative evidence of their simultaneous ecological and socioeconomic impacts across the globe. To close this knowledge gap, we propose a participatory assessment framework. Given the impacts of conventional intensification on biodiversity loss and greenhouse gas emissions, such evidence is urgently needed to direct science-policy initiatives, such as the United Nations (UN) 2030 Agenda for Sustainable Development. Copyright © 2016 Elsevier Ltd. All rights reserved.

Present state of knowledge of the upper atmosphere: An assessment report; processes that control ozone and other climatically important trace gases

NASA Technical Reports Server (NTRS)

Watson, R. T.; Geller, M. A.; Stolarski, R. S.; Hampson, R. F.

1986-01-01

The state of knowledge of the upper atmosphere was assessed as of January 1986. The physical, chemical, and radiative processes which control the spatial and temporal distribution of ozone in the atmosphere; the predicted magnitude of ozone perturbations and climate changes for a variety of trace gas scenarios; and the ozone and temperature data used to detect the presence or absence of a long term trend were discussed. This assessment report was written by a small group of NASA scientists, was peer reviewed, and is based primarily on the comprehensive international assessment document entitled Atmospheric Ozone 1985: Assessment of Our Understanding of the Processes Controlling Its Present Distribution and Change, to be published as the World Meteorological Organization Global Ozone Research and Monitoring Project Report No. 16.

Scenario analysis of the future of medicines.

PubMed Central

Leufkens, H.; Haaijer-Ruskamp, F.; Bakker, A.; Dukes, G.

1994-01-01

Planning future policy for medicines poses difficult problems. The main players in the drug business have their own views as to how the world around them functions and how the future of medicines should be shaped. In this paper we show how a scenario analysis can provide a powerful teaching device to readjust peoples' preconceptions. Scenarios are plausible, not probable or preferable, portraits of alternative futures. A series of four of alternative scenarios were constructed: "sobriety in sufficiency," "risk avoidance," "technology on demand," and "free market unfettered." Each scenario was drawn as a narrative, documented quantitatively wherever possible, that described the world as it might be if particular trends were to dominate development. The medical community and health policy markers may use scenarios to take a long term view in order to be prepared adequately for the future. PMID:7987110

Reuse Requirements for Generating Long Term Climate Data Sets

NASA Astrophysics Data System (ADS)

Fleig, A. J.

2007-12-01

Creating long term climate data sets from remotely sensed data requires a specialized form of code reuse. To detect long term trends in a geophysical parameter, such as global ozone amount or mean sea surface temperature, it is essential to be able to differentiate between real changes in the measurement and artifacts related to changes in processing algorithms or instrument characteristics. The ability to rerun the exact algorithm used to produce a given data set many years after the data was originally made is essential to create consistent long term data sets. It is possible to quickly develop a basic algorithm that will convert a perfect instrument measurement into a geophysical parameter value for a well specified set of conditions. However the devil is in the details and it takes a massive effort to develop and verify a processing system to generate high quality global climate data over all necessary conditions. As an example, from 1976 until now, over a hundred man years and eight complete reprocessings have been spent on deriving thirty years of total ozone data from multiple backscattered ultraviolet instruments. To obtain a global data set it is necessary to make numerous assumptions and to handle many special conditions (e.g. "What happens at high solar zenith angles with scattered clouds for snow covered terrain at high altitudes"?) It is easier to determine the precision of a remotely sensed data set than to determine its absolute accuracy. Fortunately if the entire data set is made with a single instrument and a constant algorithm the ability to detect long term trends is primarily determined by the precision of the measurement system rather than its absolute accuracy. However no instrument runs forever and new processing algorithms are developed over time. Introducing the resulting changes can impact the estimate of product precision and reduce the ability to estimate long term trends.Given an extended period of time when both the initial measurement system and the new one provide simultaneous measurements it may be possible to identify differences between the two systems and produce a consistent merged long term data set. Unfortunately this is often not the case. Instead it is necessary to understand the exact details of all the assumptions built into the initial processing system and to evaluate the impact of changes in each of these assumptions and of new features introduced into the next generation processing system. This is not possible without complete understanding of exactly how the original data was produced. While scientific papers and algorithm theoretical basis documents provide substantial details about the concepts they do not provide the necessary detail. Only exact processing codes with all the necessary ancillary data to run them provide the needed information. Since it will be necessary to modify the code for the new instrument it is also necessary to provide all of the tools such as table generation routines and input parameters used to generate the code. This has not been a problem for the people that make the first set of measurements of a given parameter. There was no similar predecessor global data set to match and they know what they assumed in making their measurements. But we are entering an era when it is necessary to consider the next generation. For instance the entire 30 year global ozone data set that started with the Total Ozone Mapping Spectrometer instrument launched in 1978 on the Nimbus 7 spacecraft was produced by a single science team. Similar measurements will be made well into the middle of the coming century with instruments to be flown on the National Polar Orbiting Environmental Satellite System but the original science team (unfortunately) will not be there to explain what they did over that period

The impact of baseline hemoglobin A1c levels prior to initiation of pump therapy on long-term metabolic control.

PubMed

Pinhas-Hamiel, Orit; Tzadok, Michal; Hirsh, Galit; Boyko, Valentina; Graph-Barel, Chana; Lerner-Geva, Liat; Reichman, Brian

2010-07-01

This study was done to identify factors influencing long-term metabolic control in youth with type 1 diabetes mellitus (T1DM) treated with an insulin pump. Data were obtained from retrospective chart review of 113 patients (52 males) with T1DM treated with an insulin pump for up to 7 years. Their mean +/- SD age at diagnosis of T1DM was 9.7 +/- 5.1 years, and that at pump therapy initiation was 13.8 +/- 6.1 years. Linear trends and changes in hemoglobin A1c (HbA1c) levels following pump insertion were evaluated according to gender, metabolic control prior to initiation of pump therapy, time from diagnosis of diabetes until pump therapy, age at initiation, and the duration of pump treatment. Mean HbA1c levels of patients with good baseline metabolic control (HbA1c level 9%) control groups (8.1 +/- 0.9% and 8.2 +/- 1.1%, respectively; P < 0.001). However, with time a significant trend for increasing HbA1c level was demonstrated in the group with good metabolic control (P value for trend = 0.004). HbA1c levels of patients with poor baseline metabolic control decreased significantly immediately after pump initiation (9.4 +/- 1.6% vs. 8.0 +/- 1.2%, P = 0.0001) and thereafter remained stable (P value for trend = 0.54). In the multivariable analyses, baseline HbA1c level

Trends in polycyclic aromatic hydrocarbon concentrations in the Great Lakes atmosphere

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

Ping Sun; Pierrette Blanchard; Kenneth A. Brice

2006-10-15

Atmospheric polycyclic aromatic hydrocarbon (PAHs) concentrations were measured in both the vapor and particle phases at seven sites near the Great Lakes as a part of the Integrated Atmospheric Deposition Network. Lower molecular weight PAHs, including fluorene, phenanthrene, fluoranthrene, and pyrene, were dominant in the vapor phase, and higher molecular weight PAHs, including chrysene, benzo(a)pyrene, and coronene, were dominant in the particle phase. The highest PAH concentrations in both the vapor and particle phases were observed in Chicago followed by the semiurban site at Sturgeon Point, NY. The major sources of PAHs in and around Chicago are vehicle emissions, coalmore » and natural gas combustion, and coke production. The spatial difference of PAH concentrations can be explained by the local population density. Long-term decreasing trends of most PAH concentrations were observed in both the vapor and particle phases at Chicago, with half-lives ranging from 3-10 years in the vapor phase and 5-15 years in the particle phase. At Eagle Harbor, Sleeping Bear Dunes, and Sturgeon Point, total PAH concentrations in the vapor phase showed significant, but slow, long-term decreasing trends. At the Sturgeon Point site, which was impacted by a nearby city, particle-phase PAH concentrations also declined. However, most particle-phase PAH concentrations did not show significant long-term decreasing trends at the remote sites. Seasonal trends were also observed for particle-phase PAH concentrations, which were higher in the winter and lower in the summer. 36 refs., 4 figs., 1 tab.« less

Long-term urban carbon dioxide observations reveal spatial and temporal dynamics related to urban characteristics and growth

NASA Astrophysics Data System (ADS)

Mitchell, Logan E.; Lin, John C.; Bowling, David R.; Pataki, Diane E.; Strong, Courtenay; Schauer, Andrew J.; Bares, Ryan; Bush, Susan E.; Stephens, Britton B.; Mendoza, Daniel; Mallia, Derek; Holland, Lacey; Gurney, Kevin R.; Ehleringer, James R.

2018-03-01

Cities are concentrated areas of CO2 emissions and have become the foci of policies for mitigation actions. However, atmospheric measurement networks suitable for evaluating urban emissions over time are scarce. Here we present a unique long-term (decadal) record of CO2 mole fractions from five sites across Utah’s metropolitan Salt Lake Valley. We examine “excess” CO2 above background conditions resulting from local emissions and meteorological conditions. We ascribe CO2 trends to changes in emissions, since we did not find long-term trends in atmospheric mixing proxies. Three contrasting CO2 trends emerged across urban types: negative trends at a residential-industrial site, positive trends at a site surrounded by rapid suburban growth, and relatively constant CO2 over time at multiple sites in the established, residential, and commercial urban core. Analysis of population within the atmospheric footprints of the different sites reveals approximately equal increases in population influencing the observed CO2, implying a nonlinear relationship with CO2 emissions: Population growth in rural areas that experienced suburban development was associated with increasing emissions while population growth in the developed urban core was associated with stable emissions. Four state-of-the-art global-scale emission inventories also have a nonlinear relationship with population density across the city; however, in contrast to our observations, they all have nearly constant emissions over time. Our results indicate that decadal scale changes in urban CO2 emissions are detectable through monitoring networks and constitute a valuable approach to evaluate emission inventories and studies of urban carbon cycles.

Long-Term Care: Need for a National Policy. Hearing before the Subcommittee on Health and Long-Term Care of the Select Committee on Aging. House of Representatives, Ninety-Eighth Congress, First Session (December 15, 1983, San Francisco, California).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Select Committee on Aging.

This document contains transcripts of witness testimony and prepared statements from the Congressional hearing called to review the need for a national health care policy for long-term care. Opening statements are presented from committee chairman Claude Pepper and from Representatives Sala Burton and Barbara Boxer. Testmonies are presented from…

Data for Figures and Tables in Journal Article Assessment of the Effects of Horizontal Grid Resolution on Long-Term Air Quality Trends using Coupled WRF-CMAQ Simulations, doi:10.1016/j.atmosenv.2016.02.036

EPA Pesticide Factsheets

The dataset represents the data depicted in the Figures and Tables of a Journal Manuscript with the following abstract: The objective of this study is to determine the adequacy of using a relatively coarse horizontal resolution (i.e. 36 km) to simulate long-term trends of pollutant concentrations and radiation variables with the coupled WRF-CMAQ model. WRF-CMAQ simulations over the continental United State are performed over the 2001 to 2010 time period at two different horizontal resolutions of 12 and 36 km. Both simulations used the same emission inventory and model configurations. Model results are compared both in space and time to assess the potential weaknesses and strengths of using coarse resolution in long-term air quality applications. The results show that the 36 km and 12 km simulations are comparable in terms of trends analysis for both pollutant concentrations and radiation variables. The advantage of using the coarser 36 km resolution is a significant reduction of computational cost, time and storage requirement which are key considerations when performing multiple years of simulations for trend analysis. However, if such simulations are to be used for local air quality analysis, finer horizontal resolution may be beneficial since it can provide information on local gradients. In particular, divergences between the two simulations are noticeable in urban, complex terrain and coastal regions.This dataset is associated with the following publication

Long-Term Trends in Loblolly Pine Site Productivity and Stand Characteristics Observed at the Impac Research Site in Alachua County, Florida

Treesearch

Timothy A. Martin; Eric J. Jokela

2002-01-01

While nutrient availability is a dominant factor controlling leaf area development and pine productivity in the southeastern USA, few studies have explored the long-term interactions among nutrient inputs, canopy foliage production, and aboveground biomass production. In order to address these questions, the Intensive Management Practices Assessment Center (IMPAC)...

Estimating site occupancy and detection probabilities for cooper's and sharp-shinned hawks in the Southern Sierra Nevada

Treesearch

Jennifer E. Carlson; Douglas D. Piirto; John J. Keane; Samantha J. Gill

2015-01-01

Long-term monitoring programs that can detect a population change over time can be useful for managers interested in assessing population trends in response to forest management activities for a particular species. Such long-term monitoring programs have been designed for the Northern Goshawk (Accipiter gentilis), but not for the more elusive Sharp...

Landscape context and long-term tree influences shape the dynamics of forest-meadow ecotones in mountain ecosystems

Treesearch

R.E. Haugo; C.B. Halpern; J.D. Bakker

2011-01-01

Forest-meadow ecotones are prominent and dynamic features of mountain ecosystems. Understanding how vegetation changes are shaped by long-term interactions with trees and are mediated by the physical environment is critical to predicting future trends in biological diversity across these landscapes. We examined 26 yr of vegetation change (1983-2009) across 20 forest-...

Use of Long-Term Opportunistic Surveys to Estimate Trends in Abundance of Hibernating Townsend's Big-Eared Bats

Treesearch

Theodore J. Weller; Shawn C. Thomas; James A. Baldwin

2014-01-01

The advent of broad-scale threats to bats such as white-nose syndrome and climate change highlights the need for reliable baseline assessment of their populations. However, few long-term, rigorously designed assessments of bat populations exist, particularly in western North America. Consequently, results of informal monitoring efforts are often the only data available...

Long-term watershed research and monitoring to understand ecosystem change in parks and equivalent reserves

USGS Publications Warehouse

Herrmann, R.

1997-01-01

Integrated watershed ecosystem studies in National Parks or equivalent reserves suggest that effects of external processes on 'protected' resources are subtle, chronic, and long-term. Ten years of data from National Park watersheds suggests that temperature and precipitation changes are linked to nitrogen levels in lakes and streams. We envision measurable biotic effects in these remote watersheds, if expected climate trends continue. The condition of natural resources within areas set aside for preservation are difficult to ascertain, but gaining this knowledge is the key to understanding ecosystem change and of processes operating among biotic and abiotic ecosystem components. There is increasing evidence that understanding the magnitude of variation within and between such processes can provide an early indication of environmental change and trends attributable to human-induced stress. The following four papers are case studies of how this concept has been implemented. These long-term studies have expanded our knowledge of ecosystem response to natural and human-induced stress. The existence of these sites with a commitment to gathering 'long-term' ecosystem-level data permits research activities aimed at testing more important hypotheses on ecosystem processes and structure.

Long-term Trend of Satellite-observed Chlorophyll-a Concentration Variations in the East/Japan Sea

NASA Astrophysics Data System (ADS)

Park, J. E.; PARK, K. A.

2016-02-01

Long-term time-series of satellite ocean color data enable us to analyze the effects of climate change on ocean ecosystem through chlorophyll-a concentration as a proxy for phytoplankton biomass. In this study, we constructed a 17 year-long time-series dataset (1998-2014) of chlorophyll-a concentration by combining SeaWiFS (Obrview-2, 1997-2010) and MODIS (Aqua, 2002-present) data in the East Sea (Japan Sea). Several types of errors such as anonymously high values (a speckle error), stripe-like patterns, discrepancy originating from time gap between the two satellites were eliminated to enhance the accuracy of chlorophyll-a concentration data. The composited chlorophyll-a concentration maps, passing through the post-processing of the speckle errors, were improved significantly, by 14% of abnormal variability in maximum. Using the database, we investigated spatial and temporal variability of chlorophyll-a concentration in the East Sea. Spatial distribution of long-term trend of chlorophyll-a concentration indicated obvious distinction between northern and southern regions of the subpolar front. It revealed predominant seasonal variabilities as well as long-term changes in the timings of spring bloom. This study addresses the important role of local climate change on fast changing ecosystem of the East Sea as one of miniature oceans.

Horry-Georgetown Technical College Summary Report on Institutional Effectiveness.

ERIC Educational Resources Information Center

Wilson, H. Neyle

This document is the Horry-Georgetown Technical College comprehensive assessment of missions, goals, and objectives. The assessment addressed the mission statement of the college as well as its long-term goals. The mission statement was unchanged. In regards to long-term goals for the college, the college deleted one goal that had already been…

Long-Term Autobiographical Memory for Legal Involvement: Individual and Sociocontextual Predictors

ERIC Educational Resources Information Center

Quas, Jodi A.; Alexander, Kristen Weede; Goodman, Gail S.; Ghetti, Simona; Edelstein, Robin S.; Redlich, Allison

2010-01-01

We examined adults' long-term autobiographical memory for a dramatic life event-participating as a child victim in a criminal prosecution because of alleged sexual abuse. The study is unique in several ways, including that we had extensive documentation concerning the sexual abuse allegations, the children's involvement in their legal case, and…

Research on dissociative seizures: A bibliometric analysis and visualization of the scientific landscape.

PubMed

Popkirov, Stoyan; Jungilligens, Johannes; Schlegel, Uwe; Wellmer, Jörg

2018-06-01

Dissociative seizures are a common and often elusive differential diagnosis in epilepsy centers. Considering their high prevalence, long diagnostic delays, and disappointing rates of treatment response, scientific research dedicated to dissociative seizures is surprisingly scarce. In order to chart the scientific landscape of dissociative seizures and to visualize thematic clusters and trends in research, a comprehensive bibliometric analysis was performed. The Web of Science database was examined to identify relevant English language documents from the last half-century. A total of 1751 documents with titles referring to dissociative seizures were identified. Automated textual analysis of all titles and abstracts revealed that research clusters around three major topics: differential diagnosis in epilepsy centers, management and treatment, and psychopathology. Time analysis of term networks revealed that the focus of clinical research has moved from diagnostic procedures to treatment approaches. Furthermore, interest within etiological research is shifting from an emphasis on early life trauma and personality traits to the role of anxiety and emotion regulation. With respect to individual contributing authors, a relatively small network of prolific scientists with a remarkable degree of collaboration emerges. By mapping relevant publications, it becomes evident that dissociative seizures still represent a subject mostly within the realm of neurology and epileptology, with a tendency to settle in the latter domain. This analysis sheds light on an important niche subject and highlights trends in research focus and output. Copyright © 2018 Elsevier Inc. All rights reserved.

Can MODIS detect trends in aerosol optical depth over land?

NASA Astrophysics Data System (ADS)

Fan, Xuehua; Xia, Xiang'ao; Chen, Hongbin

2018-02-01

The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard NASA's Aqua satellite has been collecting valuable data about the Earth system for more than 14 years, and one of the benefits of this is that it has made it possible to detect the long-term variation in aerosol loading across the globe. However, the long-term aerosol optical depth (AOD) trends derived from MODIS need careful validation and assessment, especially over land. Using AOD products with at least 70 months' worth of measurements collected during 2002-15 at 53 Aerosol Robotic Network (AERONET) sites over land, Mann-Kendall (MK) trends in AOD were derived and taken as the ground truth data for evaluating the corresponding results from MODIS onboard Aqua. The results showed that the AERONET AOD trends over all sites in Europe and North America, as well as most sites in Africa and Asia, can be reproduced by MODIS/Aqua. However, disagreement in AOD trends between MODIS and AERONET was found at a few sites in Australia and South America. The AOD trends calculated from AERONET instantaneous data at the MODIS overpass times were consistent with those from AERONET daily data, which suggests that the AOD trends derived from satellite measurements of 1-2 overpasses may be representative of those from daily measurements.

The Cassini Reaction Wheels: Drag and Spin-Rate Trends from an Aging Interplanetary Spacecraft at Saturn

NASA Technical Reports Server (NTRS)

Brown, Todd S.

2016-01-01

The purpose of this paper is to provide a summary of the long-term trends of the estimated drag torque and spin-rates of the Cassini reaction wheel assemblies during eleven years of intensive science operations at Saturn..

The Use of Citation Counting to Identify Research Trends

ERIC Educational Resources Information Center

Rothman, Harry; Woodhead, Michael

1971-01-01

The analysis and application of manpower statistics to identify some long-term international research trends in economic entomology and pest conrol are described. Movements in research interests, particularly towards biological methods of control, correlations between these sectors, and the difficulties encountered in the construction of a…

Upward trend in vehicle-miles resumed during 2009 : a time series analysis

DOT National Transportation Integrated Search

2010-04-01

After a 2-year interruption to a long-term upward trend, the : number of vehicle-miles traveled (VMT) on the Nations highways : appears to have resumed a pattern of upward growth in : 2009. While VMT rises and falls seasonally, the years 2007 : an...

Limnological Monitoring on the Upper Mississippi River System, 1993-1996: Long Term Resource Monitoring Program Havana Field Station

DTIC Science & Technology

2002-11-01

synopsis of the collected data and collection methods, as well as a preliminary report of remarkable or unusual conditions in the system. They are intended...resource requires scientific understanding of the ecosystem and of its long-term trends and conditions . To meet this need, Congress authorized a Long...chemical oxygen demand, biochemical oxygen demand, total coliform bacteria , fecal coliform bacteria , fecal streptococcus, heavy metals, pesticides, and

Globalization, women's migration, and the long-term-care workforce.

PubMed

Browne, Colette V; Braun, Kathryn L

2008-02-01

With the aging of the world's population comes the rising need for qualified direct long-term-care (DLTC) workers (i.e., those who provide personal care to frail and disabled older adults). Developed nations are increasingly turning to immigrant women to fill these needs. In this article, we examine the impact of three global trends-population aging, globalization, and women's migration-on the supply and demand for DLTC workers in the United States. Following an overview of these trends, we identify three areas with embedded social justice issues that are shaping the DLTC workforce in the United States, with a specific focus on immigrant workers in these settings. These include world poverty and economic inequalities, the feminization and colorization of labor (especially in long-term care), and empowerment and women's rights. We conclude with a discussion of the contradictory effects that both population aging and globalization have on immigrant women, source countries, and the long-term-care workforce in the United States. We raise a number of policy, practice, and research implications and questions. For policy makers and long-term-care administrators in receiver nations such as the United States, the meeting of DLTC worker needs with immigrants may result in greater access to needed employees but also in the continued devaluation of eldercare as a profession. Source (supply) nations must balance the real and potential economic benefits of remittances from women who migrate for labor with the negative consequences of disrupting family care traditions and draining the long-term-care workforce of those countries.

Long-term variability of aerosol optical properties and radiative effects in Northern Finland

NASA Astrophysics Data System (ADS)

Lihavainen, Heikki; Hyvärinen, Antti; Asmi, Eija; Hatakka, Juha; Viisanen, Yrjö

2017-04-01

We introduce long term dataset of aerosol scattering and absorption properties and combined aerosol optical properties measured in Pallas Atmosphere-Ecosystem Supersite in Norhern Finland. The station is located 170 km north of the Arctic Circle. The station is affected by both pristine Arctic air masses as well as long transported air pollution from northern Europe. We studied the optical properties of aerosols and their radiative effects in continental and marine air masses, including seasonal cycles and long-term trends. The average (median) scattering coefficient, backscattering fraction, absorption coefficient and single scattering albedo at the wavelength of 550 nm were 7.9 (4.4) 1/Mm, 0.13 (0.12), 0.74 (0.35) 1/Mm and 0.92 (0.93), respectively. We observed clear seasonal cycles in these variables, the scattering coefficient having high values during summer and low in fall, and absorption coefficient having high values during winter and low in fall. We found that the high values of the absorption coefficient and low values of the single scattering albedo were related to continental air masses from lower latitudes. These aerosols can induce an additional effect on the surface albedo and melting of snow. We observed the signal of the Arctic haze in marine (northern) air masses during March and April. The haze increased the value of the absorption coefficient by almost 80% and that of the scattering coefficient by about 50% compared with the annual-average values. We did not observe any long-term trend in the scattering coefficient, while our analysis showed a clear decreasing trend in the backscattering fraction and scattering Ångström exponent during winter. We also observed clear relationship with temperature and aerosol scattering coefficient. We will present also how these different features affects to aerosol direct radiative forcing.

Past Changes in the Vertical Distribution of Ozone Part 1: Measurement Techniques, Uncertainties and Availability

NASA Technical Reports Server (NTRS)

Hassler, B.; Petropavlovskikh, I.; Staehelin, J.; August, T.; Bhartia, P. K.; Clerbaux, C.; Degenstein, D.; Maziere, M. De; Dinelli, B. M.; Dudhia, A.;

Decrease in glacier coverage contributes to increased winter baseflow of Arctic rivers

NASA Astrophysics Data System (ADS)

Liljedahl, A. K.; Gaedeke, A.; Baraer, M.; Chesnokova, A.; Lebedeva, L.; Makarieva, O.; O'Neel, S.

2016-12-01

Rising minimum daily flows in northern Eurasian and North American rivers suggest a growing influence of groundwater in the Arctic hydrological cycle, while the impact of a warmer high-latitude climate system is evident in decreased glacier coverage and increasing permafrost temperatures. Multiple mechanisms have been proposed to explain the increased discharge, which is well documented but relatively poorly understood. Here we assess the long-term (up to 88 yrs) linkages between climate, glaciers and hydrology in Alaska, Canadian and Russian glacierized (from 0.3 to 60% glacier cover) and non-glacierized watersheds (31 to 186 000 km2). We are specifically interested in analyzing trends in late winter discharge from larger watersheds to refine our understanding of the regional aquifer status and annual discharge from smaller headwater basins. Field measurements of differential runoff in Interior Alaska show that glaciated headwater streams can lose significant amounts of water in summer to the underlying aquifer. The aquifer is in turn feeding the larger lowland river system throughout the year. Groundwater storage status in Arctic regions is especially prominent through winter river discharge as it is typically the only source of water to the river system for at least 6 months of the year. Our analyses aim to explore the hypothesis that the documented increase in later winter river discharge of larger watersheds can be explained at least partly, by increased glacier melt in summer as observed by long-term decreases in glacier coverage. If true, a decrease in winter freshwater exports to the Arctic Ocean could potentially follow as glaciers retreat to higher (cooler) elevations. Increased Arctic river baseflow can favor sea ice growth and fish habitats, while negatively impacting local communities in their river ice travel.

Recent trends in the registered nurse labor market in the U.S.: short-run swings on top of long-term trends.

PubMed

Buerhaus, Peter I; Auerbach, David I; Staiger, Douglas O

2007-01-01

Drawing from labor economics, background information is provided for a deeper understanding of recent changes in the nurse labor market. The difference between the short and long-run supply of RNs are distinguished, and the economic forces that determine RNs' decision to be active in the labor market are explained. The ways the nurse labor market may change in the next few years are discussed.

Spatiotemporal trends in human vulnerability to the heat across the United States

NASA Astrophysics Data System (ADS)

Sheridan, S. C.; Dixon, P. G.

2016-12-01

While human vulnerability to excessive heat has been well documented, relatively few studies have examined long-term trends in vulnerability to heat events. In this research, we examine temporal trends in mortality associated with heat waves, defined using three different definitions of heat wave, for the largest 51 metropolitan areas of the US, over a 36-year period (1975-2010). Regardless of the definition of heat wave, an overall decline in heat vulnerability is seen over the period. While in the first years of the study, 18 to 26 metropolitan areas showed statistically significant increases in mortality on heat wave days, by the final decade of the study period, this had decreased to 6 to 7. Within this narrative, however, examining individual metropolitan areas shows greater variability within the downward trend. Several contributing factors to the variability were observed, including the occurrence of an extreme heat wave affecting the overall heat wave-mortality relationship, and the frequency of heat events over a given period. These broad decreases in heat vulnerability, while encouraging, should be viewed in a cautionary sense. With society aging, there will be a greater number of highly susceptible individuals in the future; further adaptation gains are difficult in many places as air conditioning is now available in most homes in the US. Further, increased use of air conditioning has been associated with a stronger heat island; which, moving forward, is likely to occur alongside a greater number of heat events.

Long-term (2005-2014) trends in formaldehyde (HCHO) columns across North America as seen by the OMI satellite instrument: Evidence of changing emissions of volatile organic compounds

NASA Astrophysics Data System (ADS)

Zhu, Lei; Mickley, Loretta J.; Jacob, Daniel J.; Marais, Eloïse A.; Sheng, Jianxiong; Hu, Lu; Abad, Gonzalo González; Chance, Kelly

2017-07-01

Satellite observations of formaldehyde (HCHO) columns provide top-down information on emissions of highly reactive volatile organic compounds (VOCs). We examine the long-term trends in HCHO columns observed by the Ozone Monitoring Instrument from 2005 to 2014 across North America. Biogenic isoprene is the dominant source of HCHO, and its emission has a large temperature dependence. After correcting for this dependence, we find a general pattern of increases in much of North America but decreases in the southeastern U.S. Over the Houston-Galveston-Brazoria industrial area, HCHO columns decreased by 2.2% a-1 from 2005 to 2014, consistent with trends in emissions of anthropogenic VOCs. Over the Cold Lake Oil Sands in the southern Alberta in Canada, HCHO columns increased by 3.8% a-1, consistent with the increase in crude oil production there. HCHO variability in the northwestern U.S. and Midwest could be related to afforestation and corn silage production. Although NOx levels can affect the HCHO yield from isoprene oxidation, we find that decreases in anthropogenic NOx emissions made only a small contribution to the observed HCHO trends.