May 22, 2023 - NASA has selected a new mission to help humanity better understand Earth's dynamic atmosphere - specifically, ice clouds that form at high altitudes throughout tropical and sub-tropical regions. The PolSIR instrument - short for Polarized Submillimeter Ice-cloud Radiometer - will study such ice clouds to determine how and why they change throughout the day. This will provide crucial information about how to accurately simulate these high-altitude clouds in global climate models.
The investigation consists of two identical CubeSats - each small satellite is just a little over a foot tall - flying in orbits separated by three to nine hours. Over time, these two instruments will observe the clouds' daily cycle of ice content.
"Studying ice clouds is crucial for improving climate forecasts - and this will be the first time we can study ice clouds in this level of detail," said Nicola Fox, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. "Every NASA mission is carefully chosen to better understand our home planet."
The award is for for lifecycle costs no more than $37 million, which does not include launch costs. The radiometer is an Earth Venture instrument - lower-cost instruments with a targeted research goal, which typically catch a ride along with another mission or commercial satellite in order to minimize launch costs. The Earth Venture class also focuses on providing frequent flight opportunities, so innovative science investigations can be flown relatively quickly, generally within five years or less. Missions like this provide key targeted research opportunities, which help us improve our understanding of what's driving change in the entire Earth system.
"Understanding how these ice clouds respond to a changing climate - and then, in turn, contribute to further changes - remains one of the great challenges to predicting what the atmosphere will do in the future," said Karen St. Germain, who leads NASA's Earth Sciences Division. "The radiometers, which measure the radiant energy emitted by clouds, will significantly improve our understanding of how ice clouds change and respond throughout the day."
The mission is led by Ralf Bennartz, principal investigator at Vanderbilt University in Nashville, Tennessee, and by Dong Wu, deputy principal investigator at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
NASA Goddard will provide the project management team that builds the two instruments, while science operations will be conducted by the Space Science and Engineering Center at the University of Wisconsin - Madison. The two spacecraft will be built by Blue Canyon Technologies in Lafayette, Colorado.