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This paper summarizes the main results of a study on the costs of abatement of CO2 emissions in Brazil. It discusses three possible futures for the long run (2010 and 2025) activity of the Brazilian economy and -- with the help of a linear programming model for Brazil's energy sector -- three scenarios for energy production and use. One of these scenarios illustrates the possibility of halving future carbon emissions originating from energy generation and consumption, with relatively small increases in energy associated costs and investments. This abatement scenario would require, on the supply side of the Brazilian energy balance, increased amounts of hydropower, ethanol and bagasse from sugarcane, plus wood and...
Many of the most cost-effective options for reducing emissions of hydrofluorocarbons (HFCs) involve: reducing leaks; responsible handling practices; replacement with a substance with little or no global warming potential; or reducing the amount of the greenhouse gas (GHG) needed. Some of these options can be implemented immediately for quick emission reductions. However, because many of the types of equipment that rely on these gases have lifetimes ranging from 10 to 30 years, fully implementing these emission reductions can take decades. Reductions in HFC consumption, however, can generally be seen more immediately. Recent US proposals for climate legislation have considered limits on HFC consumption under a cap...
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The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2021. The RCMAP product suite consists of nine fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub, and tree, in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, we have trained time-series predictions directly from 331 high-resolution sites collected from 2013-2018 from Assessment, Inventory, and Monitoring (AIM) instead of using the 2016 “base” map as an intermediary....
Tags: AZ, Arizona, Arizona Plateau, Black Hills, Blue Mountains, All tags...
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In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been conducted on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS also has collected long-term water-quality data to support additional assessments of changing water-quality conditions. These data have been combined to provide insight into how natural features and human activities have contributed...
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In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been conducted on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS and other Federal, State, and local agencies also have collected long-term water-quality data to support their own assessments of changing water-quality conditions. Data from these multiple sources have been combined to support...
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A previously published MODFLOW-NWT groundwater-flow model for the Rush Springs aquifer in western Oklahoma (using 1 steady state stress period followed by 444 monthly stress periods representing 1979-2015; Ellis, 2018a) was used as the basis of several groundwater-use scenarios. The model is a 3-layer model including the Cloud Chief formation (confining unit of the Rush Springs aquifer), alluvial and terrace deposits, and the Rush Springs aquifer. The scenarios were used to assess the effects of increasing groundwater withdrawals from the Rush Springs aquifer on base flows to streams that flow into Fort Cobb Reservoir to address concerns over groundwater use reducing inflows to the lake. The effects of groundwater...
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Climate change over the past century has altered vegetation community composition and species distributions across rangelands in the western United States. The scale and magnitude of climatic influences are largely unknown. We used fractional component cover data for rangeland functional groups and weather data from the 1985 to 2023 reference period in conjunction with soils and topography data to develop empirical models describing the spatio-temporal variation in component cover. To investigate the ramifications of future change across the western US, we extended models based on historical relationships over the reference period to model landscape effects based on future weather conditions from two emissions scenarios...
Tags: AB, AZ, Alberta, Arizona, Arizona Plateau, All tags...
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Groundwater-quality data collected between 1993 and 2015 were compiled from the U.S. Geological Survey (USGS) National Water Information System (NWIS) database for 722 wells in the San Joaquin Valley (SJV). Groundwater-quality data retrieved included lab analyses of complete major ion data (calcium, magnesium, sodium, potassium, chloride, sulfate, nitrate, alkalinity, bicarbonate, carbonate, silica, and TDS) for 613 samples, and an additional 109 samples with measured values of specific conductance. Most of these wells were sampled as part of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project or the USGS National Water Quality Assessment (NAWQA) Program. In addition...
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This dataset utilized available water-quality data from the Mississippi Department of Environmental Quality and streamflow from the U.S. Geological Survey to estimate total nitrogen and total phosphorus loads and changes in loads from water years 2008 through 2018. Nutrient loads and changes in loads were estimated at 22 state ambient water-quality network sites, and were estimated using LOADEST regression models, Beale-Ratio Estimator, or WRTDS (Weighted Regression on Time, Discharge, and Season). The method selected is based on the evaluation of the flux-bias statistic and use of multiple graphical tools through EGRET to identify and characterize issues with particular models for each given dataset and is included...
Trends are identified changes over time in the characteristics of groundwater and (or) surface water. The characteristics analyzed can include descriptions of both quantity and quality. The calculated trends are dependent upon the available data and the methods used to identify trends. (Updated 12/23/2015)
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Groundwater quality data were collected in 5,000 wells between 1988-2001 by the National Water-Quality Assessment Project. About 1,500 of these wells were sampled again between 2002-2012 to evaluate decadal changes in groundwater quality. Monitoring wells, domestic supply wells, and some public supply wells were included in this study. All water was collected prior to treatment. Groundwater samples used to evaluate decadal change were collected from networks of wells with similar characteristics. Some networks, consisting of domestic or public supply wells, were used to assess changes in the quality of groundwater used for drinking water supply. Other networks, consisting of monitoring wells, assessed changes in...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring Network (RIM) stations for the period 1985 through 2019. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the RIM watersheds.
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This product consists of time-series calculations of anthropogenic characteristics derived for 16 data themes for multiple scales covering the conterminous United States. The characteristics are those which (a) have consistent data sources, and (b) have the potential to affect the water quality of streams and rivers. All 16 data themes are provided for Hydrologic Unit Code level-10 (HUC-10) boundaries (n = 15,458). Additionally, measures of land use and imperviousness are provided for U.S. Environmental Protection Agency (USEPA) Level 4 ecoregions (n = 967) and for U.S. counties (n = 3,109). The data may be scaled up to broader areas; that is, HUC-10 data may be scaled up to HUC-8, 6, 4, or HUC-2 areas, Level 4...
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The importance of monitoring shrublands to detect and understand changes through time is increasingly recognized as critical to management. This dataset focuses on ecological change observation over ten years of field observation at 134 plots within two sites that are located in Southwestern of Wyoming, USA from 2008-2018. At sites 1 and 3, 134 long-term field observation plots were measured annually from 2008 to 2018. General plot locations were selected in 2006 using segments and spectral clusters on QuickBird imagery to identify the best locations for representing the variability of the entire site (one QuickBird image). Ground measurements were conducted using ocular measurements with cover was estimated from...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations for the period 1985 through 2018 Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). A recently published extension of WRTDS allows users to separate these estimates into high- and low-flow conditions. This data release contains (1) a table of daily high- and low-flow concentration and load estimates for NTN stations between 1985 - 2018 and (2) an R file that contains...
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Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations for the period 1985 through 2018. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the NTN watersheds. To determine the trend in loads, the annual load results are flow normalized to integrate out the year-to-year variability in river discharge....
This paper summarizes the main results of a study on the costs of abatement of CO2 emissions in Brazil. It discusses three possible futures for the long run (2010 and 2025) activity of the Brazilian economy and -- with the help of a linear programming model for Brazil's energy sector -- three scenarios for energy production and use. One of these scenarios illustrates the possibility of halving future carbon emissions originating from energy generation and consumption, with relatively small increases in energy associated costs and investments. This abatement scenario would require, on the supply side of the Brazilian energy balance, increased amounts of hydropower, ethanol and bagasse from sugarcane, plus wood and...
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In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been conducted on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS also has collected long-term water-quality data to support additional assessments of changing water-quality conditions. These data have been combined to provide insight into how natural features and human activities have contributed...
thumbnail
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been conducted on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS and other Federal, State, and local agencies also have collected long-term water-quality data to support their own assessments of changing water-quality conditions. Data from these multiple sources have been combined to support...