NASA: Lack of sunspots to bring record cold

11/21/2018 08:36 - Posted by Tom van Leeuwen
“The sun is entering one of the deepest Solar Minima of the Space Age,” wrote Dr Tony Phillips just six weeks ago, on 27 Sep 2018.

Data from NASA’s TIMED satellite show that the thermosphere (the uppermost layer of air around our planet) is cooling and shrinking, literally decreasing the radius of the atmosphere.

NASA launched the Thermosphere-Ionosphere-Mesophere Energetics and Dynamics (TIMED) mission in 2001 to get a better picture of this outer layer. The energy that comes into it from the sun is absorbed by air molecules and reradiated to space during the normal ups and downs in solar energy that occur over a roughly 11-year time span.

The exact temperature of the thermosphere can vary substantially, but the average temperature above 180 miles (300 km) is about 800 degrees Fahrenheit (427 degrees Celsius) at solar minimum and 1,700 degrees Fahrenheit (927 degrees Celsius) at solar maximum. Though these temperatures sound hot, you would not actually feel warm in the thermosphere, because the molecules in that layer are too far apart.

During the last solar minimum, in 2009, NASA blamed part of the cooling on... CO2.

"This same cooling effect is expected to happen (somewhat counterintuitively) as carbon dioxide concentrations increase from emissions at Earth's surface, so understanding the natural variability of this layer is important to detecting any changes from carbon dioxide increases."