Climate Change: Evaluating Your Local and Regional Water Resources

Ongoing changes in climate, particularly rises in air temperature, are influencing water resources throughout the world, with shifts in the timing of precipitation, reductions in snowpack (fig. 1), and earlier springtime snowmelt among the most important challenges to water availability (fig. 2). These changes are affecting landscapes, vegetation and animal species, and agriculture, with longer dry seasons, which also create more demand on water resources, more frequent extreme storms, fewer chilling hours, and higher snow lines.

To plan for future water- and land-resource demands, resource managers have generally relied on data from global climate model projections of precipitation and air temperature trends that lack the detail needed for precision planning at regional and local scales. Recently, the U.S. Geological Survey (USGS) has developed modeling tools that integrate climate data with rigorously developed regional and local environmental data to understand the hydrologic response to climate change and the effects on regional and local watersheds and landscapes.