Study: Northern Canada Ponds Drying Up

WASHINGTON -- Ponds that have provided summertime water in the high arctic for thousands of years are drying up as global warming advances, Canadian researchers say. Falling water levels and changes in chemistry in the ponds first were noticed in the 1990s, and by last July some of the ponds that dot the landscape were dry, according to a report in Tuesday's Proceedings of the National Academy of Sciences.