Planet Earth's atmosphere consists of several layers. Humans live in the lower part, the troposphere, above which the stratosphere is 20-60 km above the surface of the planet. Carbon dioxide from the troposphere heats and expands the air mass, pushing the lower end of the stratosphere upwards. Once in the stratosphere, CO2 cools the air, causing it to shrink and thin the layer.
A new study by an international team of scientists, published in Environmental Research Letters, confirms earlier knowledge. The experts analyzed satellite observations made since the 1980s and carried out computer modelling to show that stratospheric thinning is occurring across the world, The Guardian reports.
Scientists had believed that stratospheric thinning was due to the loss of ozone, which absorbs ultraviolet light, but new research has shown that it is the rise of CO2, rather than ozone, which has begun to regrow after the banning of chemicals that deplete it.