Atmosphere Facts Height of Aurora B. 60 to 200 miles in sky Discovery of Arctic Haze 1950's by military planes Main Source of Arctic Haze Mid-latitude fossil fuel emissions Avg. Height of Arctic Haze 3 to 5 miles up Max. ozone layer depletions in Arctic 25% to 40% (Arctic Ocean, Greenland, Siberia) Did you know? The High Frequency Active Auroral Research Program (HAARP) located in Gakona, Alaska consists of 180 antenna towers in a 33 acre area. The term Arctic haze was coined in the 1950s to describe an unusual reduction in visibility that the crews of North American weather reconnaissance planes observed during their flights in the High Arctic. Arctic ozone depletion is less serious than in the Antarctic simply because the northern stratosphere is not as cold. The Arctic vortex is much more disturbed and "leaky" than its southern cousin, allowing the temperatures within it to rise.

Aurora Borealis

Auroral studies are concerned with the electromagnetic properties of the solar wind and its interaction with Earth's atmosphere, specifically at the poles. Scientists in the Arctic are attempting to predict auroral disturbances in the upper polar atmosphere based on their correlations with known solar activity. This is necessary as auroras can cause power grid outages, and can interfere with high-latitude communication, satellite orbiting, and various defense systems. In one project in Alaska, researchers are studying the artificial effects on a small region of the ionosphere caused by high power radio transmissions. In Tromso, Norway, radar sites take sensitive optical observations of the Auroral Borealis to better understand its composition.

Arctic Haze

During the 50's, reconnaissance military aircraft observed unusually reduced visibility in the Arctic. Research has shown that man-made mid-latitude emissions consisting of soot, dust, and sulphate from fossil fuel combustion were being transported northward to the Arctic from Europe and Asia. Intensive monitoring and research of 'haze' particles has identified seasonal wind and weather-induced pathways which allow contaminants to remain suspended for up to 30 days. Upon reaching the cold air masses of the higher latitudes, these sub-micrometer particles tend to 'settle' into layers of dirty air within the lower atmosphere. Here they can be leached out as acid precipitation, potentially damaging sensitive Arctic ecosystems.

Ozone Depletion & UV Radiation

Thinning of the stratospheric ozone layer has been observed and studied in the Arctic since the 1970's. Crucial to the absorption of harmful ultraviolet radiation from the sun, ozone is extremely susceptible to damage by man-made aerosol and refrigerant compounds. Readings in the Arctic over the past 30 years have shown 10% to 40% decreases in some areas. Several research sites throughout the Arctic have been established to not only better understand the mechanisms of ozone destruction but also to monitor the long term effects of UV radiation on humans and wildlife.