Atmospheric River Research

Atmospheric river storms provide approximately half of California’s annual precipitation, but also are the cause of more than 90 percent of the floods in Northern California, resulting in staggering financial costs.

Those costs are all too familiar to Yuba County, which experienced devastating flooding in both 1986 and 1997. Elements of Yuba County’s economy have never recovered.

Research partnerships

Yuba Water Agency is partnering with the Center for Western Weather and Water Extremes at UC San Diego's Scripps Institution of Oceanography, the California Department of Water Resources, U.S. Army Corps of Engineers, the National Weather Service and others on atmospheric river research and development of new tools specific to the Yuba and Feather River watersheds. This work, combined with Yuba Water’s planned Atmospheric River Control (ARC) Spillway, will substantially reduce flood risk, with potential water supply benefits as well. 

The research is focused on the Yuba and Feather River watersheds simultaneously, as Bullards and Oroville dams are operated in coordination to minimize downstream flood impacts.

All of this will be vitally important to address the adverse flood and water supply impacts expected with changing hydrology due to climate change.

Atmospheric river research in Yuba County

Throughout the winter months, Scripps scientists launch weather balloons, called radiosondes, from two locations in Yuba County for storm-specific sampling. The weather balloons measure and collect temperature, pressure, moisture and wind data to help researchers better understand the vertical structure of the atmosphere during storms, to improve atmospheric river forecasting. Researchers also use radar and drop airborne sensors from aircraft flying above the storms while they are still out over the Pacific Ocean (similar to “Hurricane Hunters”), to help build a robust data collection, while weather stations on the ground help "ground truth" conditions.

All of this data informs global weather and climate forecast models, which agencies like Yuba Water and DWR use to plan water releases from Lake Oroville and New Bullards Bar Reservoir, a coordination that is key to managing flows on the Yuba and Feather rivers and reducing flood risk for surrounding communities.

This research and the actions that will result from it are critical to reduce the risk of catastrophic flooding for the people of Yuba County.