For lovers of the forests of this country, sightings of a destructive, tree-eating beetle increasing in recent years have been nothing short of alarming.
And now, new research from the climatologists at Columbia Unversity has confirmed what ecologists have feared, that warmer winters mean the southern pine beetle is here to stay, and is set to march further across the country as temperatures continue to rise.
Historically, the tiny beetles, which starve evergreens to death, were unheard of north of the Delaware river, and the cold winters across the northern parts of the country tended to kill any intruders who managed to crawl their way up.
But now, winter is no longer cold enough.
Over the last fifty years, the average annual temperature in the northeastern United States have been warmed by about one degree Fahrenheit. But crucially for the beetles, the year’s coldest nights — which determine whether they survive the winter — have warmed by as much as 7 degrees Fahrenheit.
Southern pine beetles are now frequently spotted in New Jersey, New York and parts of New England. And their range will only grow farther as the planet continues to warm, according to a study published on Monday in the journal Nature Climate Change.
By 2020, tracks of previously unaffected land along the Atlantic Coast up all the way to Nova Scotia will become vunerable to a southern pine beetle infestation, according to the study.
By midcentury, some 40,000 square miles of the pitch pine forests from eastern Ohio to southern Maine will be hospitable to the beetle. And by 2080, vast areas of forest in the northeastern United States and into Ontario and Quebec will be vulnerable.
“You’ve probably spent summers hiking in the Adirondacks, Cape Cod, Long Island, upstate New York, the New Jersey Pinelands,” said Corey Lesk, a climate scientist at the Columbia University Center for Climate Systems Research and the study’s lead author. “All those forests are now facing a clear threat, directly, from climate change.”