Summer rains have remained steady over the past 20 years, but are less than historic highs. Temperature has increased, and while the farmland per person is decreasing, population growth has been offset with improved yields.
While summer rains have increased during the past 20 years, temperatures have increased as well, amplifying the effects of droughts. Crop yields are low but the population is growing, pointing to rising food insecurity.
Long-term reduction in rainfall and increasing temperature threaten Chad's future food production prospects; combined with rapid population growth and zones of substantial conflict, increasing numbers of people will be at risk.
Summer rains have remained steady for the past 20 years, but are below the long-term average. Current population and agricultural trends indicate increasing yields have offset population expansion, keeping per capita cereal production steady.
Modest declines in rainfall, accompanied by increases in air temperatures, declining farmland per person, along with trends in population and agriculture could lead to a 30% reduction in per capita cereal production by 2025.
Long-term reduction in rainfall and increasing temperature threaten Uganda's future food production prospects; combined with rapid population growth these factors could increase the number of people who are at risk during the next 20 years.
Analysis of sea-surface temperature in the Indian Ocean shows that warming correlates with east African rainfall; the effect on atmospheric convection and precipitation over the Indian Ocean is greater than that associated with El Niño (ENSO).
Acidified soils caused toxic aluminum in 66 percent of 565 assessed streams. Diatoms and aquatic macroinvertebrates were moderately to severely affected. These effects have not improved in areas surveyed in the early 1980s
Site for a USGS project under the U.S. Global Change Research Program for a national assessment of the impacts of climate variability and change on resources with links to impacts in Alaska, western U.S., public lands, and water resources.
Relations between the geographic distributions of woody plant species and climatic variables in North America. Shows how the spatial distribution of these plants may be expected to change in response to given climatic scenarios.
Document on the federally supported interagency National Acid Precipitation Assessment Program (NAPAP) covering research on causes and effects of acid precipitation with the USGS as the lead agency for monitoring wet acid deposition.
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.
Combining genetic data with current and predicted climate scenarios, we are modeling the predicted future distributions of wildlife populations in the Arctic and identifying key environmental variables that determine important animal habitat.
Overview of interdisciplinary research studies in Glacier National Park to understand how this mountain wilderness responds to present climatic variability and other external stressors, such as air pollution, and links to detailed reports.
Home page for Coastal and Marine Geology with links to topics of interest (sea level change, erosion, corals, pollution, sonar mapping, and others), Sound Waves monthly newsletter, field centers, regions of interest, and subject search system.
USGS responses to and studies of the hazards and impact of major hurricanes, tsunamis, and El Nino storms. Includes links to oblique aerial photography and LIDAR surveys recording coastal changes and other effects of storms and waves.
Report with mini-movie and photos on the hypothesis that the atmospheric transport of dust arising from the desertification in northern Africa led to algal infestation of corals, coral diseases, and the near extinction of associated sea urchins.
Locations for nine species of large constrictors, from published sources, along with monthly precipitation and average monthly temperature for those locations. Shapefiles for each snake species studied.
Storms bring rains strong enough to cause rock-falls and landslides that are hazardous to people. Includes examples in the eastern US with information about the weather events that precipitated the debris flows.
Explains the important paleoclimatic information we have obtained from this subaqueous cavern. The time-series data show important contrasts with what would be predicted from orbital theory, provoking extensive scientific discussion.
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.
Map display that highlights states where the streamflow index at USGS streamgages, averaged statewide, were below normal for the past seven days with links to comparison of recent streamflow values with historic values.
Homepage for Earth Surface Processes Team with research studies in two general categories: climate change and geologic mapping. Links to research activities, available data sets, workshop, and programs.
How climate change affects ground water is more complex than surface water because the residence time of ground water can range from days to tens of thousands of years. Discusses some broad climatic processes may affect groundwater resources.
Comparison of water in two adjacent watersheds before and after implementing a brush management strategy in one of the watersheds helps us see what water resource characteristics are sensitive to brush management and how.
Information from climate model forecasts, projections of future flows, paleoclimatic indicators, timing of snowmelt, airborne dust, and the effects on vegetation of troublesome pest species indicate the nature and severity of problems looming.
Integrated network of real-time water-level monitoring, ground-elevation modeling, and water-surface modeling that provides scientists and managers with current on-line water-depth information for the entire freshwater portion of the Greater Everglades.
Direct measurement of an important indicator of interannual variability is extended, using geological proxy measures, farther back in time to well before modern measurements were made. This tells us about the history of climate variability.
Map of Pleistocene pluvial lakes in the western Great Basin (Nevada, eastern California, southern Oregon). Includes metadata, online PDF map view, and downloadable ArcInfo export files, ArcView shapefiles, and TIFF files.
Accelerating loss of mass, weakening correlation with the Pacific Decadal Oscillation, and increasing mass turnover likely are the result of changes to warmer and drier climate conditions that are affecting three well-studied glaciers.
Review of the Global Change Hydrology Program components relating to hydroclimatology and studies of the biogeochemistry of greenhouse gases with links to research activities, datasets, fact sheets, and other publications and websites.
Proxy methods allow us to estimate ancient ocean temperatures but only if the method is calibrated using modern samples for which we measure the temperature. This is a proxy method using a sediment trap to collect planktonic foraminifera.
Fact sheet on the historic and current conditions of mangroves of Dry Tortugas National Park, a cluster of islands and coral reefs west of Key West, Florida. Mangroves and nesting frigate bird colonies are at risk to destruction by hurricanes.
Photographic survey of the impacts of Hurricane Katrina on the barrier islands, barrier shoreline, and the Mississippi River Delta along the Louisiana coastline. Primary focus is on the ecosystems such as fish, rookeries, and seagrass beds.
Information on video and still photography used to supplement laser altimetry measurements of the coast. The photography is used for recognizing geomorphic and cultural features impacted by storms. Links to photo collections of hurricanes and El Nino.
Airborne scanning laser surveys (LIDAR) are used to obtaining data to investigate the magnitude and causes of coastal changes that occur during severe storms. Links to examples of coastal mapping during specific hurricanes.
Description of three types of severe coastal storm impacts: hurricane impacts on the southeast U.S., extra-tropical storm impacts on the U.S. west coast during El-Nino winters, and 'northeaster' impacts on the U.S. east coast.
The Hydro-Climatic Data Network, or HCDN, consists of streamflow records for 1,659 sites throughout United States and its Territories. Records span the period 1874 through 1988, and represent a total of 73,231 water years of information.
Hydrologic monitoring data for Long Valley caldera, California, on springs, streams, wells, fumaroles, and precipitation to study the natural hydrologic variations and the response of the hydrologic system to volcanic and tectonic processes.
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.
Overview of the environmental monitoring component of the international program at the EROS Data Center using Geographic Information Systems (GIS) technology, with links to data, partners, publications, and workshops.
The Maine Cooperative Snow Survey collects, interprets, and distributes information on the depth and water content of Maine's snowpack in the late winter and early spring, when the danger of flooding in Maine's rivers and streams is greatest.
We combine long-term records from aerial photographs, detailed mapping using survey-grade GPS, and ground-based lidar with meteorological monitoring. Sand dune migration rates are currently about 35 meters per year.
The National Assessment of Coastal Change Hazards is a multi-year undertaking to identify and quantify the vulnerability of U.S. shorelines to coastal change hazards such as the effects of severe storms, sea-level rise, and shoreline erosion and retreat.
Brief report on map showing the relative vulnerability of the Atlantic coast to changes due to future rise in sea level. Includes links to similar maps in Open-file report 2000-178 on the Pacific Coast and 2000-179 on the Gulf of Mexico Coast.
Cooperative national project with the Federal Highway Administration (FHWA) to evaluate FHWA's guidelines for highway-runoff quality. Links to searchable online bibliography of related publications by the USGS, EPA, FHWA, and state agencies.
Shows where current natural hazard events are occurring within the US or worldwide, with information about the geographic extent of the hazard, the US agency engaged to work on it, and how long the hazard is expected be active.
Research and monitoring to provide the Nation with a clear understanding of natural hazards and their potential threats to society, and assists with developing smart, cost-effective strategies for achieving preparedness and resilience.
Access to map of data collection sites of the National Atmospheric Deposition Program/National Trends Network (NADP/NTN) with links to other maps and reports on wet atmospheric deposition (chemicals deposited via rain, sleet and snow).
The so-called "100-year" flood is really more like the 4 ½ year flood. This can help emergency managers enhance public awareness of how often flooding truly occurs in a region. It also could help convince those people in harm's way that preparedness is m
Planned analysis of the sensitivity of groundwater levels to changes in air temperature and precipitation. Changes in groundwater recharge and discharge also will be correlated with other hydrologic indicators.
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.
Sulfate deposition to high-elevation areas has decreased here as a result of reductions in SO2 emissions. Nitrate deposition did not change, whereas ammonium deposition increased, particularly at sites near urban and agricultural areas.
Report on the hypothesis that variations of the total solar irradiance reaching the Earth and its atmosphere affect the precipitation and runoff of the western U.S. Includes links to research papers, bibliography, and climatic data.
In 1931, the USGS established a statewide network of wells in Pennsylvania to monitor water-level fluctuations. This network consists of 68 wells to monitor ground water conditions during droughts. Links to ground-water data, hydrographs, and levels.
Lead page for detailed United States surface water information with links to real-time and historic streamflow data, suspended sediment data, USGS programs and facilities, publications, techniques, and featured news releases.
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.
Here we study effects of climate and groundwater on surface-water levels, the hydrological effects on wetland water chemistry, and the combined effects of climate, hydrology, and water chemistry on plant and animal communities of prairie pothole wetlands.
Summary of a circular on USGS environmental research and Chesapeake Bay with links to full document. Includes discussion of the problems of the estuary, restoration efforts, water quality, and effects on ecosystem.
Summary of part of the USGS interdivisional Mississippi Basin Carbon project that will study the changes in climate and the environment through carbon cycle changes recorded in lake sediments in the Upper Mississippi River Basin.
Article from American Scientist on study of the San Francisco Bay estuary as a component of the global climate system showing that natural fluctuations might be mistaken for anthropogenic trends affecting waterflow and salinity.
Topics in Coastal and Marine Sciences provides background science materials, definitions, and links to give a common context for users from a variety of backgrounds. Coastal erosion was chosen as the first topic.
Broad overview of USGS research and monitoring designed to understand current changes in the context of prehistoric and recent earth processes, distinguishing between natural and human-influenced changes, and recognizing ecological and physical responses
This updated subset of USGS streamgages for which the streamflow primarily reflects prevailing meteorological conditions for specified years, screened to exclude sites where human activity affects the natural flow of the watercourse.
Overview of research in the Hawaiian Islands and Guam to gain insight into the structure of coral reefs, to provide the basis for future monitoring, and to understand the influences of natural processes and human activities on coral reef health.
Fact sheet on the formation of acid rain, its effects, investigations, and the program of a nationwide network of acid rain monitoring stations called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN).
Over 30 years of substantial warming, the timing of life cycle events in maize here has changed, threatening the crop yield by exposing the plant at sensitive phases in its life cycle to increased heat and drought, and lowering the weight of its grains.
U.S. map of real-time streamflow compared to historical values with links to U.S. maps and data of surface water, ground water, precipitation, river conditions and floods and other information on current and past water resources conditions.
USGS water resources home page for Idaho with links to detailed hydrologic studies and real-time and long-term data on streamflow, ground and surface water, water quality, and water use, plus drought watch and relevant publications.
USGS water resources home page for Illinois with links to detailed hydrologic studies and real-time and long-term data on streamflow, ground and surface water, droughts, flooding, and water quality with highlights and project information.
USGS water resources home page for Kansas with links to detailed hydrologic studies and real-time and historical data on streamflow, ground and surface water, and water quality plus flood watch, drought watch, publications, and district news.
USGS water resource home page for Massachusetts and Rhode Island with detailed hydrologic studies and historic and real-time data on streamflow, ground and surface water, basins, floods, droughts, and water quality, plus district news.
USGS water resources home page for Michigan with links to detailed hydrologic studies and historic and real-time data on streamflow, ground and surface water, weather, water management, droughts, floods, and water quality.
USGS water resources home page for Montana with links to detailed hydrologic studies and historic and real-time data on streamflow, ground and surface water, floods, and water quality plus publications and district information.
USGS water resources home page for Nevada with links to detailed hydrologic studies and long-term and real-time data on streamflow, ground and surface water, droughts, and water quality plus district and publications information.
USGS water resources home page for New Jersey with links to hydrologic studies and historic and real-time data on streamflow, ground and surface water, droughts, weather, and water quality plus district information.
USGS water resources home page for North Carolina with links to hydrologic studies and long-term and real-time data on streamflow, ground and surface water, floods, droughts, precipitation, and water quality plus district information.
USGS water resources home page for North Dakota with links to hydrologic studies and long-term and real-time data on streamflow, ground and surface water, droughts, and water quality plus district and publications information.
USGS water resources home page for Oklahoma with links to hydrologic studies and long-term and real-time data on streamflow, ground and surface water, climatology, droughts, and water quality plus district and publications information.
USGS water resources home page for Texas with links to historic and real-time data on streamflow, ground and surface water, floods, droughts, coastal storm surge, lakes and reservoirs, and water quality plus district and publications information.
USGS water resources home page for Utah with links to detailed hydrologic studies and long-term and real-time data on streamflow, ground and surface water, and water quality plus district and publications information.
USGS water resources home page for Wyoming with links to detailed hydrologic studies and long-term and real-time data on streamflow, ground and surface water, droughts, and water quality plus district and publications information.
Homepage for project on Bear Lake, Idaho-Utah, to study past climate change and effect on lake catchment basins. Includes link to summary, personnel, geology, methods used including coring and seismic surveying, and publications.