The Airborne Snow Observatory makes a stop at Truckee Tahoe Airport in Nevada County, California. Kelly M. Grow / California Department of Water Resources

As California’s climate continues to warm, bringing more inter-seasonal climate and weather extremes, traditional hydrometeorological observation networks and forecasting procedures face significant challenges in capturing the increasingly complex hydrological responses of Sierra Nevada watersheds. Over a decade ago, the California Department of Water Resources (DWR) partnered with snow and earth science experts at NASA’s Jet Propulsion Laboratory to develop an innovative remote sensing method for measuring California’s snowpack. This collaboration resulted in the Airborne Snow Observatory (ASO) program, now an integral part of DWR’s historic California Cooperative Snow Surveys program. By providing precise snowpack measurements, the ASO program has enabled state, federal, and local water managers to better quantify the water content in California’s snowpack, leading to significant improvements in seasonal runoff forecasting and water supply management. This presentation will cover the history of DWR's ASO program and its key contributions to advancing forecasting accuracy and enhancing water management operations across California.

Meet the speaker

David Rizzardo, P.E., is a licensed Civil Engineer with over 27 years of experience in hydrology and water resources engineering. He currently manages the Hydrology Section at the California Department of Water Resources (DWR). For 23 years, David has played a pivotal role in DWR’s Hydrology Section, focusing on real-time reservoir inflow forecasting, seasonal runoff modeling, and water year predictions. Over the past 15 years, he has led several teams, including the historic California Cooperative Snow Surveys program, and has overseen the establishment and expansion of California’s Airborne Snow Observatory program, driving advancements in snowpack measurement and runoff forecasting.