Ozone & UV Facts Antarctica is the only region with more severe ozone depletions than the Arctic. Ultraviolet radiation can cause eye diseases, sunburn, & skin cancer. Marine organisms that spawn in shallow Arctic waters are particularly vulnerable to damage. Recent measurements of low ozone levels have occurred with increasing frequency, especially during the spring. Man-made chemicals called Chloroflouro-carbons (CFC's) are responsible for much of the ozone layer depletion. Did you know? The reflective snow surfaces of the Arctic can result in damaging levels of UV to unprotected eyes. Spring is often the time when Arctic biological systems are most susceptible to UV damage. Higher UV levels can jeopardize the survival of fish larvae resulting dramatic impacts for the fishing industry. Current estimates indicate that stratospheric ozone levels will continue to deplete for the next two decades.

Ozone Depletion
and UV Radiation

In the last few decades, particularly in the 1990s, attacks on Earth's protective stratospheric ozone layer have resulted in severe ozone depletion and increased ultraviolet radiation (UV) in polar regions. Considerably larger in the Arctic than at mid-latitudes, the severity of Artic ozone depletion is surpassed only by that in Antarctica. The combination of biological sensitivity, already high UV levels and increased ozone depletion in the spring could mean serious challenges for the fragile ecosystems (and human communties) of the Arctic.

Normally, ozone in the stratosphere shields the Earth from much of the harmful UV radiation. However, recent measurements in the Arctic show long-term decreases in the total ozone column, in addition to more frequent short term episodes of extremely low ozone, particularly during the springtime. Although the sun never rises far above the horizon, the highly reflective snow surface results in damaging levels of UV to unprotected eyes and vertical surfaces such as faces, trees and shrubs. Spring is often the time when biological systems are most susceptible to UV damage: natural protective measures, such as pigmentation and thickening of leaves, have not had time to develop and fish and insect larvae are most exposed.

The short growing seasons of plants and animals makes them highly vulnerable to increases in harmful solar radiation. UV effects can be particularly damaging to species at the base of the food chain. Cod, herring, pollock, salmonids, and other fish species spawn in shallow waters where the larvae can be fully exposed to ambient solar and UV radiation. UV can also affect immune suppression in humans and cause long-term health problems including cataracts, skin cancer and a number of related skin diseases. Recent research has explored the role of UV radiation in enhancing the toxicity of certain chemical compounds, especially those associated with petroleum contamination (oil spills, for example). Called photo-enhanced toxicity, the combination of UV light and certain molecules can seriously injure, and even kill, sensitive species.

Because decreased ozone levels in the Arctic are determined not only by man-made chemicals, but also by climate change, it is unclear whether or not, under current international legislation, Arctic ozone levels will return to normal. Current estimates indicate that stratospheric ozone levels will continue to deplete for the next two decades.