The Antarctic ozone hole in the Southern Hemisphere is known for its yearly variations. This year, it has a counterpart. An ozone hole has developed over the Arctic, a rare occurrence that scientists say is the biggest such atmospheric opening ever recorded over the planet’s northernmost regions. Persistent cold temperatures in the polar region and unusually quiet ozone dynamics have caused record depletion of Earth’s protective ozone layer over the Arctic, according to Paul Newman, chief scientist for Earth sciences at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
This year, frigid temperatures caused so-called polar stratospheric clouds to form at high altitudes in the Arctic. Scientists have long known that these types of clouds play a key role in the destruction of Earth’s ozone because they provide a surface high in the atmosphere for chemical reactions to take place that release harmful forms of chlorine.
The Arctic ozone hole is expected to heal and will likely disappear in the next month or so. “Our forecasts suggest that temperatures have now started to increase in the polar vortex,” Vincent-Henri Peuch, director of the European Union’s Copernicus Atmosphere Monitoring Service, which is studying the phenomenon, said in a statement. “This means that ozone depletion will slow down and eventually stop, as polar air will mix with ozone-rich air from lower latitudes.”
Source: NBC
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