Record depletion of Arctic ozone layer caused increased UV radiation in Scandinavia

Published: Tuesday, April 5, 2011 

Bremerhaven/Vienna, 05.04.2011. Over the past few days ozone-depleted air masses extended from the north pole to southern Scandinavia leading to higher than normal levels of ultraviolet (UV) radiation during sunny days in southern Finland.

These air masses will move east over the next few days, covering parts of Russia and perhaps extend as far south as the Chinese/Russian border. Such excursions of ozone-depleted air may also occur over Central Europe and could reach as far south as the Mediterranean.

On an international press conference by the World Meteorological Organisation (WMO) in Vienna today, atmospheric researcher Dr. Markus Rex from Germany´s Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association (AWI) pointed out that the current situation in the Arctic ozone layer is unparalleled.

“Such massive ozone loss has so far never occurred in the northern hemisphere, which is densely populated even at high latitudes,” AWI researcher Markus Rex describes the situation. The ozone layer protects life on Earth’s surface from harmful solar ultraviolet radiation. Because of the low inclination angle of the sun, exposure to ultraviolet radiation is not normally a public health concern at high northern latitudes.

However, if ozone-depleted air masses drift further south over Central Europe, south Canada, the US, or over Central Asiatic Russia, for example, the surface intensity of UV radiation could lead to sunburn within minutes for sensitive persons, even in April.

Whether and when this may occur can be forecasted reliably only in the short term. People should thus follow the UV forecasts of regional weather services. “If elevated levels of surface UV occur, they will last a few days and sun protection will be necessary on those days, especially for children”, Rex recommends.

“The concern is that people don’t expect to get sunburn so rapidly early in the year and consequently don’t take sun protection as seriously as in the middle of summer or while on vacation,” states Rex. Any sunburn increases the risk of developing skin cancer later in life and this adverse effect is particularly pronounced in children.

“But provided that UV-protection is used it is safe and even healthy to exercise normal outdoor activities even during low ozone episodes. Particularly in countries high up in the north people tend to suffer from vitamin D deficit after the dark winter and Sun is a natural source of it”, adds Dr. Esko Kyrö from Arctic Research Center at Finnish Meteorological Institute.

The air masses with very low ozone concentrations will eventually disperse, as the sun warms the stratosphere and the winds change, as happens every year in spring. This will lead to somewhat lower ozone in spring and early summer this year, as the low ozone from the Arctic mixes with other stratospheric air throughout the northern hemisphere. This effect will be small, due to the large dilution of the ozone depleted air masses in background air.