Wildfire and climate change amplify knowledge gaps linking mountain source-water systems and agricultural water supply in the western United States

Authors: Barnard, David; Green, Timothy; Mankin, Kyle; DeJonge, Kendall; RHOADES, CHARLES - Us Forest Service (FS); KAMPF, STEPHANIE - Colorado State University; GIOVANDO, JEREMY - Us Army Corp Of Engineers (USACE); WILKINS, MIKE - Colorado State University; Mahood, Adam; SEARS, MEGAN - Colorado State University; Comas, Louise; Gleason, Sean; Zhang, Huihui; FASSNACHT, STEVEN - Colorado State University; Harmel, Daren; ALTENHOFEN, JON - Northern Water

Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/2023
Publication Date: 8/1/2023
Citation: Barnard, D.M., Green, T.R., Mankin, K.R., DeJonge, K.C., Rhoades, C.C., Kampf, S., Giovando, J., Wilkins, M., Mahood, A.L., Sears, M., Comas, L.H., Gleason, S.M., Zhang, H., Fassnacht, S.R., Harmel, R.D., Altenhofen, J. 2023. Wildfire and climate change amplify knowledge gaps linking mountain source-water systems and agricultural water supply in the western United States. Agricultural Water Management. 286. Article e108377. https://doi.org/10.1016/j.agwat.2023.108377.
DOI: https://doi.org/10.1016/j.agwat.2023.108377

Interpretive Summary: Water resources from seasonal snowpack and rainfall in high elevation mountains are an essential freshwater source in many semi-arid regions. However, these areas are increasingly impacted by a changing climate and disturbance such as wildfire, resulting in streamflow volumes that are variable and difficult to predict. This difficulty is especially impactful to agricultural producers who rely on snowmelt and streamflow forecasts for crop selection and irrigation planning. The future of sustainable food production in the western United States depends on a reliable and predictable water source, but little research has been done to link together mountain source-water systems and agricultural water supply forecasting. In this paper we review how source water systems function and are impacted by disturbance and climate change, and relate these topics back to water supply management and forecasting, and on-farm decision making for agricultural production. Improved understanding of how mountains source waters and agricultural end users are linked will improve forecasting ability and improve food production.

Technical Abstract: Streamflow from seasonal snowpack and rainfall in high elevation mountains is an essential freshwater source in many semi-arid regions and is increasingly impacted by the effects of wildfire and a changing climate. The resulting unpredictability of water supply complicates water-use planning for downstream users, especially agricultural producers who rely on snowmelt and streamflow forecasts for irrigation planning. Securing a reliable source of clean water for agriculture that can be forecast with high confidence is made difficult by multiple sources of uncertainty, including disturbance, shifting patterns of climate and precipitation, measurement and modeling limitations, crop selection, and management strategies. To date, much research has focused on mountain processes and agricultural production separately, but there is substantial need for focused research connecting these disparate systems with improved forecasting power. Here, we overview changes to the functioning of source-water systems in the context of wildfire and a shifting climate, identify key knowledge gaps and uncertainties, and encourage researchers, resource managers, and agricultural producers to consider the interdependency of water supply source and sink relationships through improved observations and modeling to ensure sustainable food production in the western U.S.