NASA and the University of Wisconsin-Madison have collaborated to develop two miniature satellites, known as CubeSats, for a mission called PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment). These CubeSats, about the size of a shoebox, will be launched into space in a few months to study heat loss from Earth’s polar regions. The data collected by PREFIRE will help scientists predict how global warming will affect our ice, seas, and weather.
The polar regions play a crucial role in Earth’s energy balance. Heat energy received from the Sun is transported to the poles through weather and ocean currents, where it is emitted as thermal infrared radiation. However, about 60% of this energy flows out to space in far-infrared wavelengths that have never been systematically measured. PREFIRE aims to close this gap by measuring the full spectrum of heat loss from Earth’s polar regions for the first time.
Brian Drouin, scientist and deputy principal investigator for the mission at NASA’s Jet Propulsion Laboratory, explains the significance of measuring this radiation: “In climate projections, a lot of the uncertainty comes from what we don’t know about the North and South poles and how efficiently radiation is emitted into space. The importance of that radiation wasn’t realized for much of the Space Age, but we know now and are aiming to measure it.”
The CubeSats will be launched from New Zealand two weeks apart in May. Each satellite will carry a thermal infrared spectrometer, which includes specially shaped mirrors and detectors for splitting and measuring infrared light. This technology has been proven successful in studying Mars’ atmosphere and weather. Miniaturizing these instruments to fit on CubeSats was a challenge for the PREFIRE engineering team, but they managed to develop a scaled-down design optimized for Earth’s conditions.
To maximize coverage, the PREFIRE twins will orbit Earth along different paths, overlapping near the poles every few hours. This is crucial because the polar regions have experienced significant changes due to global warming. The Arctic, for example, has warmed at least three times faster than anywhere else on Earth since the 1970s. Winter sea ice in the Arctic has been shrinking rapidly, and Antarctica’s ice sheets are losing mass at an alarming rate.
These changes have far-reaching implications. Fluctuations in sea ice affect polar ecosystems and influence ocean temperatures and circulation. The melting of ice sheets in Greenland and Antarctica contributes to rising sea levels. Additionally, changes in the polar regions can impact weather patterns around the world, leading to extreme storms, flooding, and coastal erosion.
To understand and project these changes, scientists use climate models that consider various physical processes. However, uncertainties about parameters like the efficiency of thermal radiation emission from the poles can significantly impact the projections. PREFIRE aims to provide new data on climate variables such as atmospheric temperature, surface properties, water vapor, and clouds. This additional information will improve the accuracy of climate models and help scientists better understand the future of the Arctic and Antarctic.
Tristan L’Ecuyer, a professor at the University of Wisconsin-Madison and the mission’s principal investigator, emphasizes the importance of PREFIRE’s data: “As our climate models converge, we’ll start to really understand what the future’s going to look like in the Arctic and Antarctic.”
In conclusion, NASA’s PREFIRE mission using CubeSats will study heat loss from Earth’s polar regions to improve climate predictions. By measuring the full spectrum of heat loss for the first time, scientists hope to gain a better understanding of how global warming will impact our ice, seas, and weather. The data collected by PREFIRE will contribute to more accurate climate models and help us prepare for the changes that lie ahead in the Arctic and Antarctic.