Meteorologists were stunned this week when three successive thunderstorms swept through the icy Arctic from Siberia to northern Alaska, triggering lightning in an unusual phenomenon that scientists say will become less rare with global warming.
“Forecasters have never seen anything like this before,” said Ed Plumb, a meteorologist with the National Weather Service in Fairbanks, of the storms that started on Saturday.
Typically, the air over the Arctic Ocean, especially when the water is covered with ice, does not have the convective heat necessary to generate thunderstorms. But as climate change warms the Arctic faster than the rest of the world, that is changing, scientists say.
Tripling in frequency
Summer lightning episodes in the Arctic Circle have tripled since 2010, a trend directly linked to climate change and increasing sea ice loss in the High North, scientists reported in a March study published in review. Geophysical research letters. As sea ice disappears, more water can evaporate, adding moisture to the warming atmosphere.
“It’s going to go along with the temperatures,” said co-author Robert Holzworth, atmospheric physicist at the University of Washington in Seattle.
These electrical storms threaten the boreal forests bordering the Arctic as they start fires in remote areas that are already baking in the summer sun 24 hours a day.
The document also documented more frequent lightning over arctic treeless tundra regions, as well as over the Arctic Ocean and pack ice. In August 2019, lightning even struck less than 100 kilometers from the North Pole, the researchers found.
In Alaska alone, thunderstorm activity is set to triple by the turn of the century if current climate trends continue, according to two studies by scientists at the National Center for Atmospheric Research in Boulder, Colo., Published l last year in the review. Climate dynamics.
“What was very rare now is just plain rare,” said Rick Thoman, climatologist at the University of Alaska Fairbanks. As the Arctic Storm Parade demonstrated this week, lightning is already appearing in unexpected places, he said. “I have no recollection of three consecutive days of this sort of thing” in the Arctic.
On the water
On the water, lightning is a growing danger to sailors, and shipping traffic increases as the sea ice recedes, Holzworth said.
People can become lightning rods and usually try to stoop for safety reasons. It is difficult to do on a flat tundra or an expanse of ocean. âWhat you really need is to pay more attention to the lightning forecast,â he said.