Kim Holmen, research director of the Norwegian Polar Institute, stands on the roof of the Zeppelin air pollution monitoring centre on the Norwegian island of Spitsbergen, 1,200 km (750 miles) from the North Pole, in this photo taken August 21, 2007. Picture taken August 21, 2007. In the apparently pure Arctic air, a research station on a Norwegian island mountain ridge finds tiny chemical traces from factories in Russia, pesticides in Israel or China's coal-fired power plants. To match feature ARCTIC-POLLUTION/
REUTERS/STAFF