Ancient Arctic ponds drying up as climate warms

CHICAGO – Ancient ponds in the Arctic are drying up during the polar summer as warmer temperatures evaporate shallow bodies of water, Canadian researchers said this week.

They said the evaporation of these ponds – some of which have been around for thousands of years – illustrates the rapid effects of global warming, threatening bird habitats and breeding grounds and reducing drinking water for animals. For the past 24 years, researchers at the University of Alberta in Edmonton and Queen’s University in Kingston, Ontario, have been tracking ponds at Cape Herschel, located on the east coast of Ellesmere Island in Nunavut, formerly the Northwest Territories of Canada.Last year, when they went back to check, some of these 6 000-year-old ponds had vanished.”We were surprised.We arrived in early to mid-July and the ponds we had been monitoring were dry.Some of them had dried up completely.Some were just about to lose the last remaining centimetres of water,” said Marianne Douglas, director of the Canadian Circumpolar Institute at the University of Alberta.”It’s really interesting to see how quickly it is happening.We could see this trend had started a while ago but at no time did we expect it to accelerate,” said Douglas, whose work appears in the journal Proceedings of the National Academy of Sciences.Douglas said a study of the fossilised sediments in these pools of water – which are less than two metres deep – showed climate changes beginning as long as 150 years ago.The researchers had thought these ponds were permanent.But change has come rapidly.”It is a bit of a tipping point.We don’t know how far this warming or drying will go,” she said in a telephone interview.Douglas, John Smol of Queen’s University and colleagues took water samples to measure the concentration of minerals and sediments in the water.They compared it to data from the 1980s and found a significant change.Evaporation had made the sediments much more concentrated.They also discovered that ponds that formerly remained frozen until mid-July were free of ice as early as late May.”No small wonder that we are seeing evaporation occurring,” she said.”An extra month is tremendously long up there where the growing season is so short.”The changes will have significant impact on the birds and animals that rely on these sources of fresh water to survive and breed.”The ecological ramifications of these changes …will cascade throughout the Arctic ecosystem….Lower water levels will have many indirect environmental effects, such as further concentration of pollutants,” they wrote.Nampa-ReutersFor the past 24 years, researchers at the University of Alberta in Edmonton and Queen’s University in Kingston, Ontario, have been tracking ponds at Cape Herschel, located on the east coast of Ellesmere Island in Nunavut, formerly the Northwest Territories of Canada.Last year, when they went back to check, some of these 6 000-year-old ponds had vanished.”We were surprised.We arrived in early to mid-July and the ponds we had been monitoring were dry.Some of them had dried up completely.Some were just about to lose the last remaining centimetres of water,” said Marianne Douglas, director of the Canadian Circumpolar Institute at the University of Alberta.”It’s really interesting to see how quickly it is happening.We could see this trend had started a while ago but at no time did we expect it to accelerate,” said Douglas, whose work appears in the journal Proceedings of the National Academy of Sciences.Douglas said a study of the fossilised sediments in these pools of water – which are less than two metres deep – showed climate changes beginning as long as 150 years ago.The researchers had thought these ponds were permanent.But change has come rapidly.”It is a bit of a tipping point.We don’t know how far this warming or drying will go,” she said in a telephone interview.Douglas, John Smol of Queen’s University and colleagues took water samples to measure the concentration of minerals and sediments in the water.They compared it to data from the 1980s and found a significant change.Evaporation had made the sediments much more concentrated.They also discovered that ponds that formerly remained frozen until mid-July were free of ice as early as late May.”No small wonder that we are seeing evaporation occurring,” she said.”An extra month is tremendously long up there where the growing season is so short.”The changes will have significant impact on the birds and animals that rely on these sources of fresh water to survive and breed.”The ecological ramifications of these changes …will cascade throughout the Arctic ecosystem….Lower water levels will have many indirect environmental effects, such as further concentration of pollutants,” they wrote.Nampa-Reuters