UV Radiation

Inuit elders often tell the Global Warming 101 team that they get sunburned much more than in the old days.

Warmer Arctic temperatures are a double-whammy when it comes to Ultraviolet (UV) radiation exposure on living things. Although the stratospheric ozone layer is recovering over much of the world after the banning of ozone-depleting chlorofluorocarbons (CFCs), the ozone layer over the Arctic is not expected to improve much for at least a few decades. This is because of the effect of heat-trapping (greenhouse) gases on the stratospheric temperatures over the Arctic. The largest increases in UV radiation occur during the spring.

Increased levels of UV radiation are the first hit. The second blow to living things in the Arctic is reduced snow and ice cover. Plants and animals find shelter under snow and ice from UV radiation. Earlier spring thaws mean more UV exposure for living things.

Increased radiation combined with less shelter puts Arctic ecosystems at risk. Unfortunately, this increased exposure comes during the spring at the early life stages for fish and amphibians when they are most vulnerable. This increased UV radiation can also disrupt photosynthesis in plants.

Increased UV affects humans as well. Skin cancer, cataracts, and immune system disorders are all associated with UV radiation. The current generation of Arctic young people are projected to be exposed to 30% more UV than any prior generation.

Polar explorer Richard Weber told expedition member Elizabeth Andre about a North Pole expedition when all the members’ faces swelled up beyond recognition. He is convinced this swelling was due to UV radiation.

Note: Although in the Arctic, global warming is compounding the effects of reduced stratospheric ozone layers, the two issues of ozone depletion and global warming are separate. These two issues should not be confused with each other.

Stratospheric ozone depletion is caused by CFCs. Global warming, on the other hand, is caused by emissions of heat trapping [greenhouse] gases. These gases trap energy that would otherwise escape into space.

Some people erroneously think that the “hole” in the ozone layer lets more heat in from the sun and that this is a cause of global warming. This is not the case.

After CFCs were banned in 1991, the ozone layer began to repair itself. Heat-trapping (greenhouse) gases, however, continue to be emitted at ever-increasing levels.

Elizabeth

(source: ACIA, 2004)

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