About Professor Michael Retelle: Arctic meltdown

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Hometown: Grew up in Lawrence, Mass.

Came to the area: In 1987 from the University of Massachusetts

What led him to become a geologist: Was interested in hiking, skiing, climbing in the White Mountains. In high school was hiking above the tree line in Mt. Washington and met a geology class studying evidence for glaciers and ice sheets. The idea of glaciers in New Hampshire fascinated him.

What he likes about it: Being able to work outdoors on lakes and glaciers.

Family: Married to Julie Retelle, one son.

Arctic meltdown
Bates professor sees ‘big changes’ in the land of ice and snow.
The Maine economy has ‘a lot at stake.’

LEWISTON – Most people read or hear about the effects of global warming.

Michael Retelle sees it.

Since 1981, the Bates College geology professor has left his Monmouth home to spend summers in the Arctic, researching climate change for the National Science Foundation.

He, other scientists and Bates students go where the land is ice and snow, barren. The last leg of the trip is made by bush planes. It’s a place where the sun shines 24 hours a day during the summer. Where walruses roar and polar bears roam. Where in the summer the lakes never thaw.

Or, they didn’t used to.

“When I stand on the ground in the Arctic, I see that lake ice is disappearing in places where we had ice year-round,” said Retelle. “There are big changes.”

Retelle, 52, has seen those climate changes develop during the past five to 10 years.

“We’ve noticed glaciers melting more and faster,” Retelle said. “The melt season is longer, more extensive. Snow cover is changing. Some people are noting there are more winter rain events. It’s warmer.”

Sea ice used to be extensive. “It’s been retreating up Lancaster Sound, up the Northwest Passage,” he said.

As recently as 1992, lake ice was permanent. Retelle would drill a hole in May, and the next summer the drill mark would still be visible. That indicated that the ice did not melt at all. “Now, these lakes are going ice-free in the summer.”

Because of greenhouse gases from human use of fossil fuel, the planet’s warming has diverged from its natural trend, scientists warn. Retelle sees it in the lake mud cores he recovers and brings to Bates for study.

In northern Canada and Norway, Retelle and his teams drill deep into lakes, removing cores of frozen mud. Each core has annual layers of mud that represent past decades and centuries. Like tree rings, the sediment shows what’s happened to the environment.

In three lakes his team has worked on, the annual layer thickness has increased, he said. “It means the glaciers in the watershed are melting faster.” More glacier melt is carrying more sediment to the lakes.

That and other global warming evidence are cause for concern.

“The ‘Day After Tomorrow’ movie is very exaggerated,” Retelle said. “But there are parts of it we have to worry about, surprises that have to do with the links between the ocean and the atmosphere and the land.”

When glaciers and ice sheets melt, that water drains into the North Atlantic, which can dramatically cool regions. In the movie there was an instant ice age. That was a Hollywood exaggeration, Retelle said, but Arctic melt can contribute to abrupt changes.

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Maine has much at stake

Retelle doesn’t like to offer lifestyle advice on the topic of global warming. He doesn’t tell people to park their SUVs or drive less.

“I don’t like politics. I don’t like to preach,” he said.

His job, he said, is to show evidence. And that evidence is showing climate change is the biggest environmental problem facing the Earth. “It probably won’t be my generation that sees the impact. It will be the next two generations.”

Greenhouse gases in the atmosphere are melting glaciers and raising sea levels at a slow rate, about 2 millimeters a year, he said. Climate models project sea levels will rise more. By 2,100, the ocean is expected to be 6 feet higher in Maine.

“At 6 feet, you can pick up and move. But what’s a big problem is when you increase sea level and you have storm surges, that’s going to carry the impact to low-lying areas further inland.”

Maine also could feel all kinds of other impacts, he said.

With warmer temperatures, the fisheries could change. There could be more insects.”We’ve had ticks survive winters because of the temperature change,” Retelle said.

Crops and agriculture could change. “The maple sugar industry could migrate out of New England by the next century,” he said.

The winter seasons have changed. Cold snaps where temperatures plunged to below zero and stayed there for a week haven’t happened in 10 years. This year’s lack of cold and snow may become the norm. That may be fine with turnpike commuters, but much of Maine’s economy is built on the weather, Retelle said.

“Look at tourism, the snowmobile industry, the ski industry. Fishing camps. All those things depend on the Maine climate we have today. We’ve got a lot at stake.”

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