Climate scientists have found that greenhouse gases are shrinking the stratosphere, a crucial layer of our planet’s atmosphere that houses ozone and filters out ultraviolet radiation. The 35 kilometres thick stratosphere, the second layer of the Earth’s atmosphere, when going upward has shrunk by approximately 400 metres since 1980, which is about 1% of its thickness. Juan Antonio Anel, a co-author of the study and associate professor of Earth sciences at the University of Vigo in Spain, told Anadolu agency, “We discovered that the stratosphere has been contracting by more than 100 meters per decade since 1980, and we have proved that it’s due to greenhouse gases.”
The international team of scientists that Anel is a part of found that the rising emission of greenhouse gases was the main cause of this shrinkage. Greenhouse gases warm the lowest layer of the atmosphere, the troposphere, which expands as a result. An expanding troposphere creates pressure and pushes the stratosphere. Simultaneously, the carbon monoxide enters the stratosphere to cool it down. The combined result is a shrinking stratosphere, which according to scientists, will continue and the thickness of the stratosphere will decrease by an average of 1.3 kilometres by 2080 — about 4% of its total thickness. The research was published in the Environmental Research Letters journal on May 5.
To study the changing stratosphere, climate scientists used satellite data since the 1980s and combined it with chemistry-climate computer models to gain insights into the impact of greenhouse gases on the layers of the atmosphere.
The scientists have not yet studied the impacts of a shrinking stratosphere in detail, but it is likely to affect the satellite trajectories and radio communication, which the global navigation systems (GPS) use. According to the scientists, the short emergence time — 15 years — of this shrinkage makes it “a novel and independent indicator” of climate change induced by greenhouse gases. The implications of research might lead scientists to study its possible impacts on the ozone layer, housed by the shrinking stratosphere.