WINNIPEG -- Rapidly melting Arctic sea ice is changing the world's weather, releasing contaminants into the food chain and threatening the survival of whales and polar bears, a massive international study on climate change has found.
Some 300 scientists from 27 countries spent months on an icebreaker in 2009 studying the effect of climate change in the Arctic and they released their preliminary results today at a youth summit in Winnipeg.
David Barber, one of the world's top Arctic researchers, said the rapid sea-ice melt is affecting everything from polar bears to micro-organisms.
"We know we're losing sea ice. The world is all aware of that," said Barber, who holds the Canada research chair in Arctic science at the University of Manitoba. "What you're not aware of is that it has impacts on everything else that goes on in this system. We're just starting to understand that from a scientific perspective."
The expedition discovered there is more open water than ever before in the Arctic, he said. That is creating more cyclones -- Arctic storms, characterized by snow and high winds.
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The storms further erode the sea ice crucial to the region's ecosystem.
"Those storms are having a very dramatic impact on the sea ice -- they are melting the ice from underneath," Barber said. "The other thing the cyclones do is they bring winds with them. Those winds remove snow from the surface but they also break up the ice as well."
Scientists found the loss of that sea ice has both far-reaching and immediate consequences, from boosting temperatures further south to threatening whales and releasing toxic contaminants.
Steve Ferguson, who studied marine mammals on the expedition, said the melting ice has removed a barrier that once kept killer whales and other predators from entering the Arctic. Now there are more killer whales in the region and the loss of ice means there are fewer safe havens from the predator, he said.
Polar bears and other species who live on the ice are running out of room, he added.
"I think we will have ice for a long time, at least for part of the year, but it may only be located in a certain area in the world," said Ferguson, a biologist at the University of Manitoba. "These species are going to be crowded into a small area, so that's going to be challenging."
The eroding ice is also threatening mammals in another way -- by releasing contaminants into the Arctic food chain. Gary Stern, who studied the level of PCBs and mercury on the expedition, said the contaminants latch on to the increased carbon in the surface water, which is drawn downwards.
The contaminants are then consumed by zooplankton, fish and, eventually, beluga whales.
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"If you get more mercury or more PCBs into the biological system, then as the beluga feed, they're going to be feeding on those animals that have higher levels and exposing themselves to higher levels," said Stern, senior scientist with the Department of Fisheries and Oceans.
Scientists on the mission say what is happening in the Arctic is a bellwether of what will eventually happen further south.
John Hanesiak, who studied weather patterns on the expedition, said the early melt and late freeze of sea ice is contributing to more extreme weather. Not only are there more Arctic cyclones, but Hanesiak said the open water is influencing jet streams.
The increasing open water means warmer air masses further south, he said.
"We essentially see warmer falls," said Hanesiak, adding extreme weather will likely become more common as the Earth continues to heats up. "You are changing the Earth's happy place. When you start fiddling with that, then you are going to start seeing more extremes."
