USGS Science⌕ Search

SEARCH · USGS Science

Results for “Climate Change”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources

Simulation of streamflows and basin-wide hydrologic variables over several climate-change scenarios, Methow River basin, Washington

The purpose of this project was to demonstrate the capabilities of an existing watershed model and downscaling procedures to provide simulated hydrological data over various greenhouse gas emission scenarios for use in the Methow River framework prototype. An existing watershed model was used to simulate daily time series of streamflow and basin-wide hydrologic variables for baseline conditions (1990–2000), and then for all combinations of three greenhouse gas emission scenarios and five general circulation models for future conditions (2008–2095). Input data for 18 precipitation and 17 temperature model input sites were generated using statistical techniques to downscale general circulation model data. The simulated results were averaged using an 11-year moving window to characterize the central year of the window to provide simulated data for water years 2008–2095. Simulation results indicate that substantial changes of monthly mean streamflows will occur. For all greenhouse gas emission scenarios, the future streamflows are greater in the winter than baseline conditions because a greater percentage of future precipitation is projected to fall as rain rather than as snow. The simulated future spring streamflows are less than baseline conditions because the spring snowpacks are smaller; therefore, flow contributions from snowmelt are less. A database was developed to automate model execution and to provide users with Internet access to voluminous data products ranging from summary figures to model output timeseries. Database-enabled Internet tools were developed to allow users to create interactive graphs of output results based on their analysis needs. For example, users were able to create graphs by selecting time intervals, greenhouse gas emission scenarios, general circulation models, and specific hydrologic variables.

Washington↗

Prairie wetland complexes as landscape functional units in a changing climate

The wetland complex is the functional ecological unit of the prairie pothole region (PPR) of central North America. Diverse complexes of wetlands contribute high spatial and temporal environmental heterogeneity, productivity, and biodiversity to these glaciated prairie landscapes. Climatewarming simulations using the new model WETLANDSCAPE (WLS) project major reductions in water volume, shortening of hydroperiods, and less-dynamic vegetation for prairie wetland complexes. The WLS model portrays the future PPR as a much less resilient ecosystem: The western PPR will be too dry and the eastern PPR will have too few functional wetlands and nesting habitat to support historic levels of waterfowl and other wetland-dependent species. Maintaining ecosystem goods and services at current levels in a warmer climate will be a major challenge for the conservation community.

BioScience↗

Paper birch: Sentinels of climate change in the Niobrara River Valley, Nebraska

The Niobrara River Valley in the northern Great Plains supports scattered stands of paper birch ( Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation. Localized summer microclimates have likely facilitated the persistence of birch populations in a region otherwise unsuitable for the species. Dieback of canopy-sized birch has been observed throughout the valley in recent years, although no onset dates are documented. Changes in spring weather patterns may be causing rootlet injury so that trees die in spite of the still-cool summer microclimates. Current weather patterns, combined with little evidence of recruitment of young birch and great geographic distances from potential immigrant sources, make the future persistence of birch in the Niobrara River Valley stands uncertain.

Nebraska↗