NASA: The chill of solar minimum is being felt in our atmosphere – cooling trend seen

by Anthony Watts, September 28, 2018 in WUWT

These results come from the SABER instrument onboard NASA’s TIMED satellite. SABER monitors infrared emissions from carbon dioxide (CO2) and nitric oxide (NO), two substances that play a key role in the energy balance of air 100 to 300 kilometers above our planet’s surface. By measuring the infrared glow of these molecules, SABER can assess the thermal state of gas at the very top of the atmosphere–a layer researchers call “the thermosphere.”

When the thermosphere cools, it shrinks, literally decreasing the radius of Earth’s atmosphere. This shrinkage decreases aerodynamic drag on satellites in low-Earth orbit, extending their lifetimes. That’s the good news. The bad news is, it also delays the natural decay of space junk, resulting in a more cluttered environment around Earth.