The stubbornly persistent idea about climate change that just won’t go away
By Chelsea Harvey
Jul 10 2017
As if melting glaciers, thawing permafrost and starving polar bears weren’t enough, scientists are finding that the effects of climate change in the Arctic are even more complex — and far-reaching — than we thought. New research suggests that warm spells at the top of the world can, surprisingly, cause unusually cold weather in parts of North America — and that could be hurting plants, damaging agriculture and even affecting the amount of carbon dioxide that goes into our atmosphere.
Plus, it further reinforces a controversial but persistent theory suggesting that the fast-warming of the Arctic could be causing weather extremes in the heavily populated mid-latitudes as well.
The new study, just out Monday in the journal Nature Geoscience by a team of researchers from South Korea, China and the United States, finds that warmer-than-usual springtime temperatures in the Arctic Ocean are followed by colder-than-usual temperatures across much of North America, as well as a reduction in precipitation in some parts of the southern United States. And these conditions are also associated with a reduction in plant growth and development, in some cases even leading to reduced crop yields.
“This study adds to the growing pile of evidence that the indirect effects of Arctic meltdown will affect us all in surprising ways,” said Arctic climate expert Jennifer Francis of Rutgers University, who was not involved with the new research, in an email to The Washington Post.
The new study builds on a previous paper, published by some of the same authors two years ago, which explored the link between unusually warm conditions in the Arctic Ocean and unusually cold winters in both East Asia and North America. This study, along with other similar research conducted in the past few years, suggests that warming ocean temperatures and declines in Arctic sea ice can cause atmospheric changes that significantly affect weather patterns in other parts of the world.
Some scientists have suggested, for instance, that Arctic sea ice declines are contributing to longer, fiercer winters in North America by causing a shift in the “polar vortex,” the large patch of cold air flowing around the North Pole. Some of Francis’s own recent research has focused on the potential for Arctic sea ice declines to alter the circulation of a fast-flowing current of air known as the jet stream, causing it to weaken. However, these ideas remain controversial and debated within climate science.
The study from two years ago — the precursor to this week’s new research — suggested that warming over the Arctic Ocean is accompanied by a change in the circulation of winds, which cause more cold air to flow into North America. But the researchers didn’t want to stop there.
“As an extension of the paper, we thought the Arctic warming can eventually influence on the ecosystem over North America by modulating climate factors in controlling vegetation growth,” said climate scientist Jong-Seong Kug of Pohang University in South Korea, one of the new study’s authors, in an email to The Post.