The reason for this are particularly low temperatures in a high air layer, the stratosphere, and a stable polar vortex, the Research Center Julich announced on Thursday.
According to this, the ozone content has steadily decreased over the past three months and is now at the beginning of March 18 percent lower than in winters without special weather influences. Currently, however, there is no danger from high UV radiation due to the still low position of the sun.
Reading will normalize soon
The ozone layer over the Arctic is always particularly thin at this time of year during the annual cycle. According to the Julich stratospheric researchers Jens-Uwe Grooss and Rolf Muller, however, it will soon recover. “If it gets too warm for these ozone-depleting processes, the spook is quickly over,” said Muller. As soon as the temperatures rise in the next few days or weeks, the ozone depletion is stopped and the measured values normalize.
In the past decade, ozone depletion was even greater than in the past decade only in winter 2015/16. Even then, a cold period was the cause.
No recovery from CFCs yet
The production of ozone-depleting CFCs (chlorofluorocarbons) has long been banned. Nevertheless, no clear trend towards recovery has yet been discernible in the Arctic, said Muller. CFCs have a lifespan of 50 to 100 years. In the long run with one Recovery to be expected – in roughly 50 years if the production of ozone-depleting substances does not increase again, said Muller.
The ozone hole closes slowly
The ozone hole over Antarctica, the discovery of which in 1985 led to the adoption of the Montreal Protocol and the gradual ban on CFCs, seems to be slowly closing. In 2019 it was as small as it had been in around 30 years. (SDA)
Ground-level ozone acts as an irritant gas. Ozone is created in the lower atmosphere through photochemical processes. Transport, industry and solvent-based products produce nitrogen oxides and volatile organic compounds. This forms ozone in intense sunlight.
While ozone is harmful below, it is useful and even vital in the stratosphere at a height of 10 to 50 kilometers. The ozone present there envelops the earth and protects us from the ultraviolet radiation from the sun, which can cause sunburn, skin cancer and eye damage. This ozone layer is partially damaged, one speaks of the ozone hole.
The thinner the ozone layer, the more ultraviolet radiation reaches the ground. This can destroy sensitive plants that are at the beginning of the food chain. In humans, the increased ultraviolet radiation can lead to skin cancer, eye damage and other diseases.