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The atmospheric water balance over the upper Colorado River is evaluated twice daily for the seven winter seasons 1957?1963. The atmospheric water balance yields the exchange of water and water vapor at the earth-atmosphere interface through the observation of the spatial and time distributions and fluxes of water vapor in the atmosphere over the basin. The quantity precipitation minus evaporation is determined as a residual of the computation and is accumulated for daily and seasonal values. In addition, a natural period analysis is performed; the natural periods are delineated by homogeneity in the parameter precipitation minus evaporation. The dry periods are shown to exhibit a seasonal trend in evaporation rate...
Recent research has suggested that changes in temperature and precipitation events due to climate change have had a significant impact on the availability and timing of streamflow. In this study, monthly temperature and precipitation data collected over 29 climate divisions covering the entire Colorado River basin and monthly natural flow data from 29 U.S. Geological Survey (USGS) gauge locations along the Colorado River are investigated for trend or step changes using parametric and nonparametric statistical tests. Temperature increases are persistent (at least 10 climate divisions over 6 months in trend analysis) throughout the year over the Colorado River basin, whereas precipitation only notably increased over...
In the White River basin, water demand has increased with human development. Water development projects impact White River hydrology and sediment transport which can, in turn, affect resident Colorado pikeminnow populations. The objectives for this study were: 1) to compile historical biological, hydrological and physical data for the White River, 2) to analyze physical, chemical and biological features of the White River important to endangered fishes and, 3) to identify parameters for long-term monitoring to insure these features are maintained. We examined physical, chemical and biological characteristics during three development periods in the UCRB: early (1895-1945), middle (1946-1984) and post Taylor Draw...
We investigate herein the hypothesis that there is a significant relationship between bed particle mobility and benthic invertebrate abundance in the gravel-bed channel of the upper Colorado River in Rocky Mountain National Park. A large diversion channel called the Grand Ditch normally diverts a significant portion (?50%) of the annual snowmelt runoff from the watershed northward out of the basin. In May 2003, a ?30-m section of the ditch was breached, contributing substantially to the magnitude and duration of discharge in the Colorado River until the ditch breach was repaired in July of that year. As a result, all grain sizes in the river channel were mobilized, which contrasted sharply with the minimal gravel...
The Colorado River supplies water to 27 million users in 7 states and 2 countries and irrigates over 3 million acres of farmland. Global climate models almost unanimously project that human-induced climate change will reduce runoff in this region by 10-30%. This work explores whether currently scheduled future water deliveries from the Colorado River system are sustainable under different climate-change scenarios. If climate change reduces runoff by 10%, scheduled deliveries will be missed approximately 58% of the time by 2050. If runoff reduces 20%, they will be missed approximately 88% of the time. The mean shortfall when full deliveries cannot be met increases from approximately 0.5-0.7 billion cubic meters per...
The development and the application of ArcCN-Runoff tool, an extension of ESRI@ ArcGIS software, are reported. This tool can be applied to determine curve numbers and to calculate runoff or infiltration for a rainfall event in a watershed. Implementation of GIS techniques such as dissolving, intersecting, and a curve-number reference table improve efficiency. Technical processing time may be reduced from days, if not weeks, to hours for producing spatially varied curve number and runoff maps. An application example for a watershed in Lyon County and Osage County, Kansas, USA, is presented.
Daily VEMAP output from the Hadley Coupled Climate Model (HadCM2) and land use projections from the Southeastern Michigan Council of Governments are used to examine the impacts of climate change and land use change on a regional watershed in southeastern lower Michigan. The precipitation, temperature, moisture, and solar radiation output from HadCM2 are processed before they are used as input to a modified version of the Biosphere-Atmosphere Transfer Scheme (BATS). The modified BATS model (BATS/HYDRO) includes the original 18 BATS land use types along with six new urban land classes as well as an improved surface runoff model, which accounts for impervious surfaces and depression storage. The daily VEMAP output...
Summary Non-point nitrogen (N) and phosphorus (P) pollution from agriculture has increasingly received more public attention. In this study, NO3–N, dissolved P (DP) and particulate P (PP) concentrations and loads were investigated for four sub-basins (labeled 1–4 going up the watershed) within a mixed land use watershed (39.5 ha) in the Appalachian Valley and Ridge Physiographic Province. The hot moments of NO3–N concentration and load occurred in base flow and during the non-growing season. Great and temporally variable DP and PP concentrations were observed in storm flow. The hot moments of DP concentration and load were in storm flow from May to December and from September to Nov, respectively, while the hot...
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The U.S. Geological Survey (USGS) is providing an online map of water-table altitude contours in the upper glacial and Magothy aquifers on Long Island, New York, April-May 2013. USGS serves this map and geospatial data as a REST Open Map Service (as well as HTTP, JSON, KML, and shapefile), so end-users can use the map and data on mobile and web clients. A companion report, U.S. Geological Survey Scientific Investigations Map 3326 (Como and others, 2015; http://dx.doi.org/10.3133/sim3326) further describes data collection and map preparation and presents 68x22 in. PDF versions, 4 sheets, scale 1:125,000. This polyline shapefile consists of digital contours that represent the water table altitude in the upper...
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Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in distribution and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtropical drylands is well constrained, whereas soil moisture and ecological droughts, which drive vegetation productivity and composition, remain poorly understood in temperate drylands. Here we show that, over the 21st century, temperate drylands may contract by a third, primarily converting to subtropical drylands,...
In 2015, the Red River Basin experienced the tail end of a severe drought followed by exceptional flooding, both of which cause impacts to industry, agriculture, tourism and the environment. Scientists, water managers and other stakeholders are interested in knowing what is in store for the future of the Red River Basin. Researchers at the University of Oklahoma and the Choctaw and Chickasaw Nations developed projections of future hydrology for the Red River Basin under possible future climate conditions. A methodology was developed for using current state of the art Global Climate Models (GCM) and applying them on a scale suitable for hydrologic models, ultimately making the information useful to water managers...
The influence of woody vegetation and biological soil crusts on infiltration capacity is one of the several uncertainties associated with the ecohydrologic effects of woody plant encroachment into arid and semi-arid land systems. The objective of this study was to quantify the effects of Utah juniper (Juniperus osteosperma) and pinyon pine (Pinus edulis) on subcanopy and intercanopy ecohydrologic properties. We measured soil sorptivity, unsaturated hydraulic conductivity [K(h)], soil water content (SWC), and water repellency along radial line transects from under Juniperus and Pinus trees into the centre of the intercanopy space between trees. In the subcanopy, litter mounds, hydrophobic soils, and roots all appear...
The hydrology and geomorphology of large rivers in America reflect the pervasive influence of an extensive water control infrastructure including more than 75,000 dams. One hundred thirty-seven of the very large dams, each storing 1.2 km3 (106 acre feet) of water or more, alter the flows of every large river in the country. The hydrologic effects of these very large dams emerge from an analysis of the stream gage records of 72 river reaches organized into 36 pairs. One member of each pair is an unregulated reach above a dam, whereas the other is a regulated reach downstream from the same structure. Comparison of the regulated and unregulated reaches shows that very large dams, on average, reduce annual peak discharges...
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The U.S. Geological Survey (USGS) is providing an online map of stream and lake gage water level measurements on Long Island, New York, April-May 2013. USGS serves this map and geospatial data as a REST Open Map Service (as well as HTTP, JSON, KML, and shapefile), so end-users can use the map and data on mobile and web clients. A companion report, U.S. Geological Survey Scientific Investigations Map 3326 (Como and others, 2015; http://dx.doi.org/10.3133/sim3326) further describes data collection and map preparation and presents 68x22 in. PDF versions, 4 sheets, scale 1:125,000. Continuous records of water level altitude at 16 U.S. Geological Survey (USGS) streamgaging stations (15 streams and...
How groundwater flow varies when long-term external conditions change is little documented. Geochemical evidence shows that sea-level rise at the end of the last glacial period led to a shift in the flow patterns of coastal groundwater beneath Florida.
Aim A regional analysis was used to explore the influence of river regulation on the dominance of non-native, invasive shrubs and trees. We addressed the following questions: (1) How do large dams affect hydrological parameters that influence riparian vegetation? (2) How do flow regimes affect the dominance of non-native woody species? (3) How do changes in flow regimes affect the dominance of non-native woody species? Location South-western USA. Methods We sampled the canopy cover of woody species on 179 point bars along seven non-dammed and thirteen dammed river segments. Wilcoxon rank sum tests were used to determine differences between flow parameters in dammed and non-dammed rivers. We used correlation analyses...
Agriculture is the leading source of nonpoint-source pollution on a national scale. the driving force of nonpoint-source pollution is the rainfall-runoff process, which is the transformation of rainfall to streamflow. This is a complex, nonlinear, time-varying, and spatially distributed process on the watershed scale that is difficult to effectively model by conventional, deterministic means. Artificial neural networks (ANNs) offer a new approach to forecasting the hydrologic and water quality response of a watershed system. The goal of this work is to develop an ANN model as a long-term forecuating tool for predicting the hydrology and water quality of agricultural watersheds where the physical processes are difficult...
This recorded presentation is from the April 17, 2014 workshop for the "Integrated Scenarios of the Future Northwest Environment" project. The recording is available on YouTube. The Integrated Scenarios project is an effort to understand and predict the effects of climate change on the Northwest's climate, hydrology, and vegetation. The project was funded by the Northwest Climate Science Center and the Climate Impacts Research Consortium.
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The U.S. Geological Survey (USGS) is providing an online map of water level measurements in the Magothy and Jameco aquifers on Long Island, New York, April-May 2013. USGS serves this map and geospatial data as a REST Open Map Service (as well as HTTP, JSON, KML, and shapefile), so end-users can use the map and data on mobile and web clients. A companion report, U.S. Geological Survey Scientific Investigations Map 3326 (Como and others, 2015; http://dx.doi.org/10.3133/sim3326) further describes data collection and map preparation and presents 68x22 in. PDF versions, 4 sheets, scale 1:125,000. The potentiometric surface altitude was measured at 70 observation wells and 31 supply wells screened...
map background search result map search result map Water Level Data in the Magothy and Jameco Aquifers, April-May 2013 Stream and Lake Average Water-Level Altitudes, April-May 2013 Contours of Water Table Altitudes in the Upper Glacial and Magothy Aquifers, April-May 2013 Stream and Lake Average Water-Level Altitudes, April-May 2013 Water Level Data in the Magothy and Jameco Aquifers, April-May 2013 Contours of Water Table Altitudes in the Upper Glacial and Magothy Aquifers, April-May 2013