How much heat is escaping through Earth's polar windows?
The Arctic is warming three times faster than the rest of the planet. To understand why, NASA is launching two shoebox-sized satellites to solve an atmospheric mystery: how clouds and water vapor at the poles regulate the heat escaping into space.
Earth’s climate relies on a delicate energy balance. While the tropics absorb significant solar energy, weather and ocean currents transport much of that heat toward the poles. To regulate the planet's temperature, the Arctic and Antarctic must radiate much of this heat back into space. However, scientists have lacked a systematic way to measure this heat in the form of far-infrared radiation.
NASA’s PREFIRE mission—the Polar Radiant Energy in the Far-InfraRed Experiment—aims to fill this gap using two CubeSats. These small satellites will monitor the amount of heat Earth emits from its most remote regions. The mission is particularly focused on the role of clouds and water vapor, which act like windows for the planet. On a clear, dry day, heat escapes easily; on a cloudy, humid day, the atmosphere acts like a closed window, trapping radiation and contributing to the greenhouse effect.
The complexity lies in the clouds themselves. Low-altitude clouds made of water droplets often have a cooling effect, while high-altitude clouds composed of ice particles tend to absorb heat and warm the atmosphere. Mid-altitude clouds are even more unpredictable, capable of either warming or cooling depending on their composition. Because these microscopic particles change within seconds, they are notoriously difficult to model. By measuring far-infrared emissions, PREFIRE will provide the data necessary to improve the computer models used to predict sea ice loss, ice-sheet melting, and future global climate change.
Source: A Mission to Better Understand Earth’s Polar Regions (Mission Overview)
