"Climate change impacts on winter and spring hydrology in a temperate region"

Monday, April 8, 2013 - 4:00pm
Eastern Daylight Time
Evan Murdock
University of Wisconsin Madison

As the scientific consensus on the reality of climate change has become near-absolute,  there has grown to be considerable interest in predicting its impacts on environmental services. Of particular concern are impacts on water resources, as flooding, drought, water availability, and other water-related issues have profound impacts on people’s lives and livelihoods.

Unfortunately, considerable uncertainty remains about how precipitation patterns may change in the future, limiting the ability of planners to react to these changes. Given this difficulty it is reasonable to pursue those elements of water resources that are most influenced by temperature change. In Wisconsin’s temperate climate, these processes are winter snowfall, snowmelt, and soil frost formation.

The one-dimensional Simultaneous Heat and Water (SHAW) model was used to simulate two continuous 29-year periods representing historical (1970-1999) and future (2040-2069) climate conditions in southern Wisconsin, based on downscaled GCM data from the North American Regional Climate Change Assessment Program (NARCCAP).

Modeling showed that warmer winter and spring temperatures lead to a decrease in runoff and a commensurate increase in recharge. Additional modeling with the frost portion of the model disabled confirmed the importance of soil frost formation to the results. These results held across different climate models and a wide range of soil types.