As they churn across the top of the globe each year they leave warm water and air in their wakes, melting sea ice in the Arctic Ocean, scientists at Ohio State University reported Wednesday.
An analysis of arctic storms from 2000 to 2010 found 40 percent more of the cyclones that had previously been estimated, they said.
"We now know there were more cyclones than previously thought, simply because we've gotten better at detecting them," geography Professor David Bromwich said.
Many of the cyclones previously missed were small in size and short in duration, or occurred in unpopulated areas, he said.
The study area was north of 55 degrees latitude, which includes the northern reaches of Canada, Scandinavia and Russia, along with the state of Alaska.
"We can't yet tell if the number of cyclones is increasing or decreasing, because that would take a multidecade view," Bromwich said. "We do know that, since 2000, there have been a lot of rapid changes in the arctic -- Greenland ice melting, tundra thawing -- so we can say that we're capturing a good view of what's happening in the Arctic during the current time of rapid changes."
As an example, he cited an especially large cyclone that hit the arctic in August 2012, which scientists say they believe played a significant role in the record retreat of sea ice that year.
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