the Unusual weather conditions were not only in the Arctic but also in Antarctica for a record to be responsible. The ozone hole over the South pole was in the last October never been so small since 1982 as the U.S. space Agency Nasa reported on the basis of satellite data.

The researchers put into perspective, however: It was not a "sudden accelerated recovery" for the people of the vital ozone layer. The reason for the amazing phenomenon of certain weather conditions, which resulted in the Antarctic late winter and spring, in September and October, an unusual warming of the higher air layers are.

This was a single event. Generally speaking, the ozone layer is recovering more slowly than scientists expected. The Montreal Protocol, the production and consumption of ozone-depleting substances, especially chlorofluorocarbons (CFCs), controlled, been in force since 1989. Since then, the substances were reduced in the atmosphere massively. Nevertheless, the recovery is slow. Since the year 2000, has stabilized the ozone layer, but the fluctuations from year to year are still big. Studies even show that the ozone levels anywhere in the stratosphere at a height of between 10 and 50 kilometers, signs of improvement show. So far, scientists puzzle over the cause. According to the current Knowledge of ozone, researchers expect that the ozone layer over the Antarctic, the natural state before 1980 to 2070 again.

on success of the Montreal Protocol is not only of benefit to the ozone layer. With the ban of CFCs, the production of these substances was prevented, as the greenhouse gas CO2 have a warming effect on the atmosphere. New model calculations show that the CFCs for the strong warming of the Arctic could be responsible. (lae)

Created: 05.03.2020, 12:51 PM