RENO-TAHOE INTERNATIONAL AIRPORT, Nev. --
The 53rd Weather Reconnaissance Squadron “Hurricane Hunters” have temporarily traded the mild climate of their home station, Keesler Air Force Base, Mississippi, for chilly Reno, Nevada 1,800 miles away, in order to support atmospheric river reconnaissance in conjunction with the National Oceanic and Atmospheric Association and the National Centers for Environmental Protection.
For the past several years, during the winter, the Air Force Reserve unit has deployed some of its aircraft and aircrews to various places such as Hawaii, Alaska, and California to into fly large swaths of moisture over the pacific called atmospheric rivers.
“An atmospheric river is a ribbon of concentrated moisture in the atmosphere that moves with weather systems and transports water vapor from the tropics,” said Maj. Sonia Walker, 53rd WRS aerial reconnaissance weather officer. “This condensed moisture becomes rain and snow when the river makes landfall.”
Similar to hurricane operations, the 53rd flies, with their specially equipped WC-130J Super Hercules aircraft, and releases dropsondes able to collect various atmospheric data such as humidity, pressure, and wind speed and direction, but other than that the missions are quite different.
Unlike during a hurricane mission where the crew flies at around 10,000 feet, Walker said AR missions are flown at much higher altitudes, around the 25,000 to 30,000 feet range.
“In an AR mission, we fly as high as we can and track through and around the river,” said Walker. “The altitude allows our dropsondes the maximum time and space to measure atmospheric conditions from flight level to the ocean’s surface.”
Also, according to Master Sgt. Chris Becvar, loadmaster for the 53rd, one of the main differences is the amount of dropsondes released.
“During a hurricane we drop around 12 to 18, but because the atmospheric rivers often cover a larger, more undefined area, and are not organized like hurricanes, we drop around 30 per mission to make sure we sample as much as possible,” said Becvar.
Walker said that the purpose of the mission is strictly data collection during the AR flights as opposed to hurricane missions where there are the objectives of locating the center of the storm and measuring its intensity.
The data collected is sent to NCEP that disseminates the information to forecasters to integrate the atmospheric data into models and researchers at Scripps Institution of Oceanography at the University of California – San Diego.
Considering the remote and vast area the atmospheric rivers are coming from, meteorologists do not have access to much data for forecasting purposes without the reconnaissance flights, and ultimately, it is important and beneficial to the millions of people who inhabit the West Coast.
Flying these systems supports water management decisions and flooding forecasts which is crucial in a region prone to droughts and wildfires, said Walker. Long periods of time without moisture, or freshly scorched earth can result in lack of absorption of the precipitation caused by AR’s leading to flooding, landslides and more.
“With hurricanes, it’s very easy to see the direct impacts of a storm because they’re so violent; thus, it’s easy to see the importance of our mission into them,” said Walker. “Just because the impacts aren’t always so dramatic or obvious, the data we collect in these atmospheric rivers is just as important.”
The unit expects to continue providing AR support until mid-March.