Grantee Research Project Results
Assessing Climate Change Impacts to the Quantity and Seasonality of Ground Water Recharge in the Basin and Range Province of the Western United StatesEPA Grant Number: FP917491
Title: Assessing Climate Change Impacts to the Quantity and Seasonality of Ground Water Recharge in the Basin and Range Province of the Western United States
Investigators: Neff, Kirstin L
Institution: University of Arizona
EPA Project Officer: Just, Theodore J.
Project Period: August 20, 2012 through August 19, 2015
Project Amount: $126,000
RFA: STAR Graduate Fellowships (2012)
Research Category: Academic Fellowships , Fellowship - Hydrology
Ground water recharge replenishes aquifers, a primary source of freshwater for human consumption and riparian areas. It is critical to understand the current ground water recharge regimes in the Western United States and how those regimes might shift in the face of climate change, impacting the quantity and composition of riparian ground water. This research will address the following questions: How does the seasonality of ground water recharge vary in the Basin and Range Province? How is the quantity and seasonality of ground water recharge related to the size of riparian areas? How will the quantity and seasonality of ground water recharge change with climate change?Approach:
This research will characterize ground water recharge regimes in study basins throughout the Basin and Range Province, extending from northern Mexico to the U.S. states of Nevada and Utah. It is comprised of new field investigations using water chemistry analysis and computer modeling to partition incoming precipitation into recharge, runoff and evapotranspiration, as well as the amalgamation and analysis of existing data for the region. The result will be a survey of current conditions with an eye toward how they might change with climate change.Expected Results:
Watersheds in the Basin and Range Province are characterized by a bimodal precipitation regime of dry summers and wet winters. The current assumption is that the relative contributions to ground water recharge by summer and winter precipitation varies throughout the province, with winter precipitation dominating in the northern parts of the region and summer floods playing a more significant role in the south, where the North American Monsoon extends its influence. In the future, climatologists expect a shift northward of precipitation and temperature norms as surface temperatures increase across the region, and a survey of recharge regimes up and down the basin and range could provide a space-for-time substitution in predicting future hydrologic conditions throughout the region.
Potential to Further Environmental/Human Health Protection
Establishing a robust understanding of the current relationship between the seasonality and quantity of precipitation and ground water recharge processes will allow for predictions of how recharge regimes might change in the future, and thus how the quantity and quality of freshwater for human use and ecosystems also might change. This research will provide the foundation for better management of ground water resources, helping to plan for future human use and the conservation of delicate ground water-fed riparian ecosystems and the valuable ecosystem services they provide to the surrounding semi-arid communities, including public health and economic benefits.Supplemental Keywords:
ground water recharge, climate change, riparian health