Evaluation of Exposure and Vulnerability of Selected Inland National Wildlife Refuges in the Pacific Southwest to Water Resources Constraints in the Face of Climate Change using Downscaled Climate Change Modeling

Science Center Objects

As competition for water is growing, a major challenge is to ensure that sufficient quantities of good quality water are available for fish, wildlife, and plants. Competition for a limited supply of water with adequate water quality to support National Wildlife Refuges are a dominant threat for many National Wildlife Refuges across the U.S. and is only heightened during times of drought and in the light of climate change.

Map of Modoc Regional Wildlife Refuge.

Map of Modoc Regional Wildlife Refuge.

(Public domain.)

The purpose of this project is to evaluate the effect of climate change on refuge water management at the refuge scale to assist with identifying water resources constraints to current and planned habitat management objectives. This analysis will include estimates of the effects of projected climate change on (1) water supply and availability (amount, timing of delivery, and frequency of extreme events), and (2) potential and actual evapotranspiration within refuge boundaries and calculation of climatic water deficit.

The U.S. Geological Survey California Water Science Center (USGS), in cooperation with many partners and processing support from University of California, Davis Information Center for the Environment (ICE) has developed a regional water balance model (Basin Characterization Model, BCM). This model is driven by high resolution (270 meter) downscaled precipitation and temperature data that is used to characterize water budget at the land surface for current and future climates. This project proposes to use this dataset to estimate potential changes in water availability and demand for one FWS refuge as a phase I exercise to establish proof of concept. ICE will participate to provide processing and analytical support.

This project will consider several priority water-resource issues identified in Circular 1309 (USGS, 2007), including developing tools with which to predict ecosystem change on the basis of water availability, quantifying, forecasting, and securing freshwater for our future, and, in particular, assessing the consequences of climate change. This proposal will also support capabilities within the CAWSC to develop hydrologic modeling tools relevant to the present science issues underlying the management of watersheds and hydrologic hazards in light of changes expected under future climate conditions. This project relates explicitly to the mission of WRD to provide scientific information that will be utilized by decision-makers to effectively manage the landscape and water resources for water-related natural hazards, recreational and ecological use, aquatic health, and environmental quality. In addition, the development of these basin-scale modeling tools describing climate scenarios are relevant to other federally managed lands in California for optimization of water resources.