Scientists have found that the upper part of the Earth’s atmosphere is gradually shrinking – they believe this is a response to growing anthropogenic greenhouse gas emissions.
Combined data from three NASA satellites made it possible to obtain data that the mesosphere, the layer of the atmosphere at an altitude of 40-50 to 80-90 km above the surface, is cooling and contracting. Scientists have long predicted this effect of anthropogenic climate change, but could not observe the phenomenon in real-time.
“We need several decades to understand these trends and isolate what is happening due to greenhouse gas emissions, changes in the solar cycle, and other effects,” said Scott Bailey of the Virginia Institute of Technology. “In the meantime, we have managed to collect data from three satellites to answer some of the questions.”
The satellites provided materials for about 30 years of observations. They showed that the summer mesosphere over the Earth’s poles cools by 10 degrees Celsius and shrinks by 120 m per decade. The researchers expect these rates to continue unchanged by anthropogenic carbon dioxide emissions.
This cooling and contraction did not come as a surprise to scientists. They already assumed that phenomena exist and talked about them, since several AI-based models at once indicated their existence. “It would be weirder if our analysis of the data did not show this,” the researchers note.
Although researchers have tried to record the cooling before, none of them used data of this duration and did not show the compression of the upper atmosphere. The researchers say the new findings boost their confidence in their ability to simulate complex changes in the upper atmosphere.