21-02-2025
U.S. Air Force hurricane hunters being used to study atmospheric rivers in California
YUBA COUNTY – The Yuba Water Agency is partnering with the Scripps Institute of Oceanography to collect data on atmospheric rivers through weather balloons. Now, part of that research includes heavy-duty hurricane aircraft.
Researchers are using a U.S. Air Force WC-130 J Hurricane Hunter to study atmospheric rivers.
"We do have our hurricane season and we do fly hurricanes in tropical systems. But we also, in the winter time, fly winter storms and now we're also a part of atmospheric rivers," said U.S. Air Force Aerial Reconnaissance Weather Officer Amaryllis Cotto.
A partnership spanning several agencies—Yuba Water, the Department of Water Resources, the U.S. Air Force, and Scripps Institute of Oceanography—is working to better understand atmospheric rivers.
"The one thing with California is that it's really the land of extremes, it's either feast or famine. The variability from year to year, in terms of the amount of precipitation that falls, is the most varied compared to anywhere else in the United States," said research and operations meteorologist for the Center for Western Weather and Water Extremes Chad Hecht.
Too many or too few atmospheric rivers can be a determining factor of flood or drought. So researchers are learning more about them to help with the forecast and optimize water management.
"This place is a very good location for us because of, one, the proximity of the atmospheric rivers for us and, two, just how the weather is here we can easily come in and come out," Cotto said.
Atmospheric river research flights are typically done from January through March. Teams are flying out from Mather Air Base to the Pacific Ocean.
"The Pacific Ocean is very data smart and these are really the best ways to go out and observe these storms. And if these forecast models don't know what's going on over the Pacific Ocean, they're not going to forecast them well as they make landfall over California," Hecht said.
"They're looking at how the storm is developing as it comes closer to the shore, to the west coast," Cotto said.
During a typical mission, there are about 25 drop sondes that are dropped out of the plane to collect data.
"It has a parachute on it and as it drops through the storm it collects data that allows them to draw a vertical map of the storm," said U.S. Air Force Master Sgt. John Douglas.
"If we've had a couple atmospheric rivers that aren't really producing a lot of rain then they try to conserve more water in certain areas. But if it is going to be a heavy rainfall event, they might be talking about releasing the water from the dams," Cotto said.
All of this data collected from the flights are sent back to weather centers to compile and compare, ultimately improving storm predictability and forecasting.
"In a warming climate, we're seeing that variability is becoming even more so and California is becoming even more dependent on these atmospheric rivers to provide the water necessary for agriculture and drinking and other uses across the state," Hecht said.
While atmospheric rivers have been around throughout history, they were only given a name in the 1990s. Researchers say understanding them could play a key role in California's water management going forward.
