As part of the U.S. Geological Survey Groundwater Resources Program study of Appalachian Plateaus aquifers, mean-annual and mean-seasonal water-budget estimates for the period 1980 through 2011 were determined for a 162,000 square-mile area covering parts of New York, Pennsylvania, Maryland, Ohio, West Virginia, Kentucky, Virginia, Tennessee, North Carolina, Georgia, Alabama, and Mississippi. Mean-annual and mean-seasonal precipitation, recharge, and actual evapotranspiration (ET) estimates were derived from annual and monthly Soil-Water-Balance (SWB) model (McCoy and others, 2015; Westenbroek and others, 2010) output and compiled in a geodatabase. Precipitation estimates from the Appalachian Plateaus SWB model were derived from daily Daymet climate grids (Thornton and others, 2012). Estimates of recharge from the SWB model were calculated using a modified Thornthwaite-Mather soil-water accounting method (Thornthwaite and Mather, 1957; Westenbroek and others, 2010). Estimates of ET from the SWB model were derived by adjusting a spatially-variable estimate of potential ET (Hargreaves and Samani, 1985) with estimates of precipitation and soil-moisture (Westenbrok and others, 2010). The geodatabase contains polygon and point feature classes representing the model grid cells and their centers, respectively, and two tables containing mean-annual and mean-seasonal estimates for each cell. Mean-annual estimates were computed for full calendar years (January through December) and are presented in inches per year (in/yr) for the 1980 through 2011 period. Mean-seasonal estimates for spring (March through May), summer (June through August) and fall (September through November) are presented in inches for the 1980 through 2011 period. Mean-seasonal estimates for winter (December through February), also presented in inches, were calculated for December 1980 through February 2011.

As part of the U.S. Geological Survey’s Groundwater Resources Program study of the Appalachian Plateaus aquifers, estimates of annual water-budget components were determined at 849 continuous-record streamflow gaging stations from Mississippi to New York. Base flow, which can serve as a proxy for annual recharge, streamflow, and runoff were estimated from computer programs—PART (Rutledge, 1993), HYSEP (Sloto and Crouse, 1996), and BFI (Wahl and Wahl, 1988)—that are included in the hydrograph analysis component provided with version 1.0 of the U.S. Geological Survey Groundwater Toolbox. Only complete years (January to December) of record at each gage were used to determine annual estimates. Estimates of base-flow index, which is the percentage of streamflow from base flow, are included in the annual and average tables. Precipitation was estimated by calculating the average of cell values in the PRISM dataset intercepted by basin boundaries where previously defined in the GAGES-II dataset (Falcone, 2011). Estimates of evapotranspiration were then calculated from the difference between precipitation and streamflow.

As part of the U.S. Geological Survey’s Groundwater Resources Program study of the Appalachian Plateaus aquifers, estimates of annual water-budget components were determined at 849 continuous-record streamflow gaging stations from Mississippi to New York. Base flow, which can serve as a proxy for annual recharge, streamflow, and runoff were estimated from computer programs—PART (Rutledge, 1993), HYSEP (Sloto and Crouse, 1996), and BFI (Wahl and Wahl, 1988)—that are included in the hydrograph analysis component provided with version 1.0 of the U.S. Geological Survey Groundwater Toolbox. Only complete years (January to December) of record at each gage were used to determine annual estimates. Estimates of base-flow index, which is the percentage of streamflow from base flow, are included in the annual and average tables. Precipitation was estimated by calculating the average of cell values in the PRISM dataset intercepted by basin boundaries where previously defined in the GAGES-II dataset (Falcone, 2011). Estimates of evapotranspiration were then calculated from the difference between precipitation and streamflow.

As part of the U.S. Geological Survey’s Groundwater Resources Program study of the Appalachian Plateaus aquifers, estimates of annual water-budget components were determined at 849 continuous-record streamflow gaging stations from Mississippi to New York. Base flow, which can serve as a proxy for annual recharge, streamflow, and runoff were estimated from computer programs—PART (Rutledge, 1993), HYSEP (Sloto and Crouse, 1996), and BFI (Wahl and Wahl, 1988)—that are included in the hydrograph analysis component provided with version 1.0 of the U.S. Geological Survey Groundwater Toolbox. Only complete years (January to December) of record at each gage were used to determine annual estimates. Estimates of base-flow index, which is the percentage of streamflow from base flow, are included in the annual and average tables. Precipitation was estimated by calculating the average of cell values in the PRISM dataset intercepted by basin boundaries where previously defined in the GAGES-II dataset (Falcone, 2011). Estimates of evapotranspiration were then calculated from the difference between precipitation and streamflow.

As part of the U.S. Geological Survey’s Groundwater Resources Program study of the Appalachian Plateaus aquifers, estimates of annual water-budget components were determined at 849 continuous-record streamflow gaging stations from Mississippi to New York. Base flow, which can serve as a proxy for annual recharge, streamflow, and runoff were estimated from computer programs—PART (Rutledge, 1993), HYSEP (Sloto and Crouse, 1996), and BFI (Wahl and Wahl, 1988)—that are included in the hydrograph analysis component provided with version 1.0 of the U.S. Geological Survey Groundwater Toolbox. Only complete years (January to December) of record at each gage were used to determine annual estimates. Estimates of base-flow index, which is the percentage of streamflow from base flow, are included in the annual and average tables. Precipitation was estimated by calculating the average of cell values in the PRISM dataset intercepted by basin boundaries where previously defined in the GAGES-II dataset (Falcone, 2011). Estimates of evapotranspiration were then calculated from the difference between precipitation and streamflow.

This data release provides 64 forecasted water budget simulations for the Mississippi Embayment Regional Aquifer System (MERAS) during the period 2019 to 2055. Gridded daily data (1-kilometer resolution) include net infiltration (potential groundwater recharge), rejected net infiltration, interception, runoff, runoff outside (runoff that cannot be routed downslope), irrigation, actual evapotranspiration, minimum and maximum temperatures, and gross precipitation. The gridded representations of water budget components are output from USGS Soil-Water-Balance (SWB) model (Nielsen and Westenbroek, 2023; Westenbroek and Nielsen, 2023) simulations in netcdf4 format, and all water budget components are in inches. The precipitation, maximum air temperature, and minimum air temperature data used as climatic input to the SWB model application were derived from Coupled Model Intercomparison Project Phase 5 (CMIP5) projections (Brekke and others, 2013), downscaled using Localized Constructed Analogs (LOCA; Pierce and others, 2014) to a 1/16 degree spatial resolution. The SWB model produced output based on 64 CMIP5 climate projections, half of which are Representative Concentration Pathway (RCP) 4.5 and half of which are RCP 8.5 greenhouse gas concentration trajectories. All 64 forecasted climate model outputs can be accessed through the child items: RCP_4_5 and RCP_8_5. Outputs for each climate model scenario are housed in a zipped folder named after the respective climate scenario. Each zipped folder contains ten files: actual_et__2019-01-01_to_2055-12-31__989_by_661.nc, gross_precipitation__2019-01-01_to_2055-12-31__989_by_661.nc, interception__2019-01-01_to_2055-12-31__989_by_661.nc, irrigation__2019-01-01_to_2055-12-31__989_by_661.nc, net_infiltration__2019-01-01_to_2055-12-31__989_by_661.nc, rejected_net_infiltration__2019-01-01_to_2055-12-31__989_by_661.nc, runoff__2019-01-01_to_2055-12-31__989_by_661.nc, runoff_outside__2019-01-01_to_2055-12-31__989_by_661.nc, tmax__2019-01-01_to_2055-12-31__989_by_661.nc, and tmin__2019-01-01_to_2055-12-31__989_by_661.nc. Further details about the SWB model used to produce the water budget forecasts can be found in Nielsen and Westenbroek (2023).

This data release provides 64 forecasted water budget simulations for the Mississippi Embayment Regional Aquifer System (MERAS) during the period 2019 to 2055. Gridded daily data (1-kilometer resolution) include net infiltration (potential groundwater recharge), rejected net infiltration, interception, runoff, runoff outside (runoff that cannot be routed downslope), irrigation, actual evapotranspiration, minimum and maximum temperatures, and gross precipitation. The gridded representations of water budget components are output from USGS Soil-Water-Balance (SWB) model (Nielsen and Westenbroek, 2023; Westenbroek and Nielsen, 2023) simulations in netcdf4 format, and all water budget components are in inches. The precipitation, maximum air temperature, and minimum air temperature data used as climatic input to the SWB model application were derived from Coupled Model Intercomparison Project Phase 5 (CMIP5) projections (Brekke and others, 2013), downscaled using Localized Constructed Analogs (LOCA; Pierce and others, 2014) to a 1/16 degree spatial resolution. The SWB model produced output based on 64 CMIP5 climate projections, half of which are Representative Concentration Pathway (RCP) 4.5 and half of which are RCP 8.5 greenhouse gas concentration trajectories. All 64 forecasted climate model outputs can be accessed through the child items: RCP_4_5 and RCP_8_5. Outputs for each climate model scenario are housed in a zipped folder named after the respective climate scenario. Each zipped folder contains ten files: actual_et__2019-01-01_to_2055-12-31__989_by_661.nc, gross_precipitation__2019-01-01_to_2055-12-31__989_by_661.nc, interception__2019-01-01_to_2055-12-31__989_by_661.nc, irrigation__2019-01-01_to_2055-12-31__989_by_661.nc, net_infiltration__2019-01-01_to_2055-12-31__989_by_661.nc, rejected_net_infiltration__2019-01-01_to_2055-12-31__989_by_661.nc, runoff__2019-01-01_to_2055-12-31__989_by_661.nc, runoff_outside__2019-01-01_to_2055-12-31__989_by_661.nc, tmax__2019-01-01_to_2055-12-31__989_by_661.nc, and tmin__2019-01-01_to_2055-12-31__989_by_661.nc. Further details about the SWB model used to produce the water budget forecasts can be found in Nielsen and Westenbroek (2023).

Data used to estimate monthly water budgets at Panola Mountain Research Watershed, Panola Mountain State Park, Stockbridge, Ga. for water years 1986–2015. Data include: (1) hourly air temperature and solar radiation data used to calculate potential evapotranspiration using the Priestly-Taylor equation; (2) unit-value streamwater stage and streamflow; (3) unit-value base flow determined from a hydrography separation using the Eckhardt filter, (4) daily water budgets components, and; (5) edit code descriptions for streamwater stage and precipitation data for items 2 and 4.

Data used to estimate monthly water budgets at Panola Mountain Research Watershed, Panola Mountain State Park, Stockbridge, Ga. for water years 1986–2015. Data include: (1) hourly air temperature and solar radiation data used to calculate potential evapotranspiration using the Priestly-Taylor equation; (2) unit-value streamwater stage and streamflow; (3) unit-value base flow determined from a hydrography separation using the Eckhardt filter, (4) daily water budgets components, and; (5) edit code descriptions for streamwater stage and precipitation data for items 2 and 4.

As part of the National Water Census program in the Apalachicola-Chattahoochee-Flint (ACF) River Basin, the U.S. Geological Survey evaluated the groundwater budget of the lower ACF, with particular emphasis on recharge, characterizing the spatial and temporal relation between surface water and groundwater, and groundwater pumping. To evaluate the hydrologic budget of the lower ACF River Basin, a groundwater-flow model, constructed using MODFLOW-2005, was developed for the Upper Floridan aquifer and overlying semiconfining unit for 2008–12. Model input included temporally and spatially variable specified recharge, estimated using a preliminary version of a Precipitation-Runoff Modeling System (PRMS) model for the ACF River Basin, and pumping, partly estimated on the basis of measured agricultural pumping rates in Georgia. The model was calibrated to measured groundwater levels, and base flows which were estimated using hydrograph separation. The simulated groundwater flow budget resulted in a net cumulative loss in groundwater storage during the study period. Spatial variability in simulated hydrologic budgets for eight subbasins was attributed to such factors as soil storage capacity, Lake Seminole impoundment, and the presence of in-channel springs. The model simulated a net storage loss for all the subbasins. The model is limited by its conceptualization, the data used to represent and calibrate the model, and the mathematical representation of the system; therefore, any interpretations should be considered in light of these limitations. In spite of these limitations, the model provides insight regarding water availability in the lower ACF River Basin. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20175141).