An analysis of satellite observations shows that ozone levels in the Arctic have reached an all-time low in March, NASA researchers said. The ozone level reached its lowest point on March 12 at 205 Dobson units. Depletion was caused by unusually weak upper air wave events from December 2019 to March of this year.
"As far as the overall health of the ozone layer is concerned, this is a concern as ozone levels in the Arctic are usually high in March and April," said Paul Newman, chief earth scientist at NASA's Goddard Space Flight Center.
Ozone is a highly reactive molecule of three oxygen atoms that naturally occurs in small amounts. The stratospheric ozone layer, which is about 11-40 km above the Earth's surface, acts as a sunscreen that absorbs ultraviolet radiation that is harmful to living things.
These waves travel upward from the mid-latitude of the lower atmosphere to interrupt the circumpolar winds that revolve around the Arctic. When they destroy the polar winds, they capture ozone from other parts of the stratosphere with them, rebuilding the reservoir over the Arctic.
