Mathematical model of the groundwater system in this area includes 13 types of data and spans multiple aquifers over more than a century. This enables us to assess the quantity of groundwater, where and how it is being used, and how pumping affects it.
Wildlife you see in a national park or other reserved area don't know about the park boundary. Bobcat, martens, mink, and moose need different types of living space and habitat. Development outside the park affects their ability to inhabit the park.
Congress asked us (in the Energy Independence and Security Act of 2007) to figure out how to assess the effects of carbon storage, sequestration, and greenhouse gas fluxes in our ecosystems. Here's how we plan to do that.
Using ground-water geochemical analyses, and mathematical models, the factors affecting the quality of public water supply were identified as pumping schedule, screened interval, past land use within the recharge area, and natural geochemical conditions.
Using ground-water geochemical analyses and mathematical models, the factors affecting the quality of public water supply were identified as mixing of very recent recharge with older water, karst features, natural geochemical processes, and pumping.
Well vulnerability results from the young age of groundwater. Karst features permit contaminants to move into the aquifer easily, leading to a well mixed aquifer; geochemical processes do not degrade contaminants quickly.
Explains the natural and human-affected factors that determine the concentration of contaminants in groundwater, especially where the concentration is different at the surface than at depth, and where pumping varies with time.
Small wetlands in this large area have hosted migratory birds for a long time, but with changes in agricultural practice and regional climate those habitats may not remain hospitable to the wild populations.
Boston Harbor/Massachusetts Bay Studies research project conducted as part of Boston Harbor cleanup to predict the fate of contaminants and sediments introduced to Massachusetts' coastal waters from sources that include Boston sewage outfall.
Summary of an investigation of the Cascadia subduction zone with detailed density-modeling experiments of the crust and mantle along two transects across Vancouver Island and the Canadian margin and the other on the margin of central Oregon.
Polar bears are endangered by reduction in Arctic sea-ice concentration and by reduction in their supply of prey for food. Models shown here indicate anticipated effects on polar bear populations of several climate change scenarios.
Three themes of ongoing research: forecasting polar bear and walrus population response to changing marine ecosystems; measuring wildlife population changes in the Arctic coastal plain, and wildlife communities in the boreal-Arctic transition zone.
Three mathematical models using information about the geographic distribution and character of land surface characteristics along with proposed modifications or plausible events to determine the likely costs and benefits of actions and events.
Proposed removal of dams will change the characteristics of stream flow and will affect fish that swim upstream to spawn. A mathematical model of the river flow tells us where the likely problems will be located and how the flow will change.
Research exploring the mathematical properties of kriging, a widely-used surface interpolation method. The continuity properties of kriging digital terrain models over a wide range of terrain types helps hydrologists assess the usefulness of kriging for D
The Vegetation Drought Response Index is a drought monitoring and mapping tool integrating satellite observations of vegetation and climate with land cover, soil characteristics, and other environmental factors.
Site to locate most recent or archive reports for end-of-the-month hydrologic conditions with descriptions, data, charts, and maps giving an overview of water conditions during the month for the state of New York.
Methods to depict the connectedness of rock units across fault and fracture zones, allowing us to determine the distribution of geologic units, structural features, and other controlling factors, such as porosity and permeability.
Lead page to connect to ground water information on the Nation's ground water resources and ground water activities of the USGS. Includes links to ground-water data, news reports, publications, field techniques, models, programs, and issues.
Using a geographic dataset of structures, with more than 5500 structures that were destroyed or damaged by wildfire since 2001, we identified the main contributors to property loss in two extensive, fire-prone regions in southern California.
Shows how observations and modeling can help anticipate practical problems in coastal areas when hurricanes arrive. Focuses primarily on areas where people have built houses and roads that may be destroyed during storms.
Recent physical changes over time, including trends toward earlier snowmelt runoff, decreasing river ice, and increasing spring water temperatures, may affect salmon populations; we want to know how important these effects are.
Complex geographic information can be analyzed with mathematical models to show us the spatial patterns of human building, vegetation growth, and other landscape characteristics that may result from environmental changes we may expect in the future.
Study to identify grasslands that may be suitable for cellulosic feedstock production. Producing ethanol from non-cropland areas such as grassland will minimize the effects of biofuel developments on global food supplies.
Provides standards and guidance for measuring, estimating, collecting, and analyzing water-use data. Includes brief descriptions of water-use activities, commonly used water-use terminology, and approaches and methods used in estimating water use.
Primary homepage for the National Water Quality Assessment (NAWQA) Program studying water quality in river, aquifer and coastal water basins throughout the nation. Links to reports, data, models, maps and national synthesis studies.
Links to reports for Pennsylvania on borehole geophysical studies, aquifer tests and properties, modeling, and hydrologic effects of an earthquake with links to MOC3D solute transport software package, program mission, and bibliography.
Report on the Sirenia Project use of a radio tracking study to determine manatee movement patterns and habitat to develop ecological models to understand and predict the effects of hydrologic restoration on manatees in Southwest Florida.
Research projects intended to create regional and national data that conform to conditions predicted by general circulation models, so that land and wildlife managers can understand the likely consequences of climatic changes in their areas of study.
This report consists of materials prepared for a GIS spatial analysis course intended for instructors preparing spatial-modeling training and scientists with advanced GIS expertise. Downloads available in many formats (PDF, ArcView, Word, etc.)
Software based on the MODFLOW modeling framework, used for studies of saltwater intrusion coastal aquifers, storage and recovery in brackish limestone aquifers, and brine migration in continental aquifers.
GIS application for assessing, mapping, and quantifying the social value of ecosystem services. Helps decision makers consider tradeoffs among them with the human attitudes and preferences that express underlying social values.
The USGS Surface-water quality and flow Modeling Interest Group (SMIG) is interested in surface-water quality and flow modeling activities with links to articles, model archives, data archives, clearinghouse, mailing list, classes, and meetings.
Explains 16 distinct types of scientific information that are needed to understand climate change, including the specific parameters measured, why they are needed, who measures them, and the type and amount of information that are not yet available.
Upcoming interagency study to assess status of ecological conditions, their relationships with contaminants and nutrients, anthropogenic factors affecting these, and develop models that may predict these ecological conditions.
To assess the effectiveness of ecological carbon sequestration, we plan to define ecosystem reporting units, model baseline and potential carbon sequestration, develop spatial models that simulate ecosystems, and integrate remote sensing data.
Usually we choose to put water monitoring stations in places where we have no data already. But it's more efficient to place stations so that they help to reduce uncertainty in the results of modeling. This analysis shows how to choose.
This report presents a visual, statistical presentation of five modeled flow-management alternatives and two reference alternatives for four selected sites on the Lower Missouri to aid in decision making for flow management of the river.
Description of the development and use of models to study watersheds supporting a broad range of applications and user skills. Includes links to related memos, training, software, projects, and references
Links to published materials produced by the Watershed Processes and Modeling Project on watershed model TOPMODEL, compilation of STATSGO soils data, climate change, landscape heterogeneity in ecoregions, and other links.