The Earth’s climate has changed significantly over the last 100 years. Changes however have not been uniform—different ecological systems have experienced different changes. Here, we use 4 km resolution climate data maps from 1901 to 2006 in conjunction with the 2002 National Land Cover Dataset, to assess the degree to which different habitat types have differentially experienced changes in minimum temperature, maximum temperature, and precipitation within 57 major ecoregions in the contiguous United States.

Results/Conclusions

In the entire study area, we found agricultural areas experienced the greatest change in minimum temperatures (2.0 ^oC per century), shrub/grasslands experienced the greatest change in maximum temperatures (0.83 ^oC per century), and barren areas experienced the greatest percent change in precipitation (15% per century). When analyzing specific ecoregions, we found that forests within the Mojave desert ecoregion (southwest US) have experienced the greatest change in maximum temperatures (2.4 ^oC per century), agricultural areas in the great central valley of California have experienced the greatest change in minimum temperatures (2.4 ^oC per century), and barren areas in the west Cascades ecoregion (northwest US) have experienced the greatest change in precipitation (42.1 cm per century). The greatest decreases in maximum temperatures were Mississippi alluvial plains barren areas (-0.8 ^oC per century), the greatest decreases in minimum temperatures were in south Atlantic coastal plains barren areas (-0.7 ^oC per century), and the greatest decreases in precipitation were in southern Rocky mountains forests (-12.4 cm per century). Our results demonstrate the need to analyze climatic change within specific ecosystems and habitat types. This approach can be used for prioritizing ecological systems in terms of climate change impacts and provides an environmental context for ecological studies within specific ecosystems.