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A time and frequency-domain analysis is made of the effects of averaging and sampling methods used for constructing magnetic-observatory hourly data values. Using 1-min data as a proxy for continuous, geomagnetic variation, we construct synthetic hourly values of two standard types: instantaneous "spot" measurements and simple 1-h "boxcar" averages. We...

This data set represents the area of each level 3 nutrient ecoregion in square meters, compiled for every catchment of NHDPlus for the conterminous United States. The source data are from the 2002 version of the U.S. Environmental Protection Agency's (USEPA) Aggregations of Level III Ecoregions for National Nutrient...

We present 29 movie‐maps of low‐latitude horizontal‐intensity magnetic disturbance for the years 1999–2006: 28 recording magnetic storms and 1 magnetically quiescent period. The movie‐maps are derived from magnetic vector time series data collected at up to 25 ground‐based observatories. Using a technique similar to that used in the calculation of Dst,...

The U.S. Geological Survey (USGS) used six distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program / National Trends Network (NTN) and Mercury Deposition Network (MDN) during 2007-08. The field-audit program assessed the effects of onsite exposure, sample handling, and shipping on the chemistry of NTN...

This data set represents the mean percent impervious surface from the Imperviousness Layer of the National Land Cover Dataset 2001 (LaMotte and Wieczorek, 2010), compiled for every catchment of NHDPlus for the conterminous United States. The source data set represents imperviousness for the conterminous United States for 2001. The Imperviousness...

This report documents methods for data compilation and analysis of statistics for stormflows that meet data-quality objectives for order-of-magnitude planning-level water-quality estimates at unmonitored sites in the conterminous United States. Statistics for prestorm streamflow, precipitation, and runoff coefficients are used to model stormflows for use with the Stochastic Empirical Loading and Dilution Model...

We use laser altimetry from the Ice, Cloud, and land Elevation Satellite (ICESat) to map the grounding zone (GZ) of the Ross Ice Shelf, Antarctica, at 491 locations where ICESat tracks cross the grounding line (GL). Ice flexure in the GZ occurs as the ice shelf responds to short-term sea-level...

This tabular data set represents the mean value for infiltration-excess overland flow as estimated by the watershed model TOPMODEL, compiled for every catchment of NHDPlus for the conterminous United States. Infiltration-excess overland flow, expressed as a percent of total overland flow, is simulated in TOPMODEL as precipitation that exceeds the...

This data set represents the area of bedrock geology types in square meters compiled for every catchment of NHDPlus for the conterminous United States. The source data set is the "Geology of the Conterminous United States at 1:2,500,000 Scale--A Digital Representation of the 1974 P.B. King and H.M. Beikman Map"...

This tabular data set represents the mean base-flow index expressed as a percent, compiled for every catchment in NHDPlus for the conterminous United States. Base flow is the component of streamflow that can be attributed to ground-water discharge into streams. The source data set is Base-Flow Index for the Conterminous...

This data set represents the area of Hydrologic Landscape Regions (HLR) compiled for every catchment of NHDPlus for the conterminous United States. The source data set is a 100-meter version of Hydrologic Landscape Regions of the United States (Wolock, 2003). HLR groups watersheds on the basis of similarities in land-surface...

This data set represents basin characteristics, compiled for every catchment in NHDPlus for the conterminous United States. These characteristics are basin shape index, stream density, sinuosity, mean elevation, mean slope, and number of road-stream crossings. The source data sets are the U.S. Environmental Protection Agency's NHDPlus and the U.S. Census...

Precipitation chemistry and depth measurements obtained by the Canadian Air and Precipitation Monitoring Network (CAPMoN) and the US National Atmospheric Deposition Program/National Trends Network (NADP/NTN) were compared for the 10-year period 1995–2004. Colocated sets of CAPMoN and NADP instrumentation, consisting of precipitation collectors and rain gages, were operated simultaneously per...

This data set represents the estimated amount of phosphorus and nitrogen fertilizers applied to selected crops for the year 2002, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is based on 2002 fertilizer data (Ruddy and others, 2006) and tabulated by crop type...

This data set represents the average atmospheric (wet) deposition, in kilograms per square kilometer, of inorganic nitrogen for the year 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data set for wet deposition was from the USGS's raster data set atmospheric (wet) deposition of...

A new waveform inversion for crosswell radar is formulated in the frequency-domain for a 2.5D model. The inversion simulates radar waves using the vector Helmholtz equation for electromagnetic waves. The objective function is minimized using a backpropagation method suitable for a 2.5D model. The inversion is tested by processing crosswell...

Wildfire enhances the geomorphic response of a watershed to precipitation events, effectively altering the form of the hillslope and channel drainage network. Typically, drainage networks expand following rainfall on a recently burned watershed. Expansion of drainage networks following wildfire increases in erosion and sediment transport rates, and the probability of...

This tabular dataset represents the estimated area of artificial drainage for the year 1992 and irrigation types for the year 1997 compiled for every catchment of NHDPlus for the conterminous United States. The source datasets were derived from tabular National Resource Inventory (NRI) datasets created by the National Resources Conservation...

This data set represents the average contact time, in units of days, compiled for every catchment of NHDPlus for the conterminous United States. Contact time, as described in Wolock and others (1989), is the baseflow residence time in the subsurface. The source data set was the U.S. Geological Survey's (USGS)...

Proper understanding of the physical properties of hydrate-bearing sediments is required for interpretation of borehole logs and exploration geophysical data, the analysis of borehole and submarine slope stability, and the formulation of reservoir simulation and production models. Yet current knowledge of geophysical and geotechnical properties of hydrate-bearing sediments is still...

This data set represents the 30-year (1971-2000) average annual maximum temperature in Celsius multiplied by 100 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the United States Average Monthly or Annual Minimum Temperature, 1971 - 2000 raster dataset produced by the PRISM Group...

Executive Summary: The classification and distribution mapping of the vegetation of Canyon de Chelly National Monument (CACH) and surrounding environment was accomplished through a multi-agency effort between 2003 and 2007. The National Park Service’s Southern Colorado Plateau Network facilitated the team that conducted the work, which comprised the U.S. Geological...

We explored the use of continuous waterborne electrical imaging (CWEI), in conjunction with fiber‐optic distributed temperature sensor (FO‐DTS) monitoring, to improve the conceptual model for uranium transport within the Columbia River corridor at the Hanford 300 Area, Washington. We first inverted resistivity and induced polarization CWEI data sets for distributions...

This data set represents the average monthly maximum temperature in Celsius multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the Near-Real-Time High-Resolution Monthly Average Maximum/Minimum Temperature for the Conterminous United States for 2002 raster dataset produced by the...

The Greater Yellowstone Ecosystem (GYE) supports the southernmost of the 2 largest remaining grizzly bear (Ursus arctos) populations in the contiguous United States. Since the mid-1980s, this population has increased in numbers and expanded in range. However, concerns for its long-term genetic health remain because of its presumed continued isolation....