NEW YORK — New England's maple trees stop producing sap. The Long Island and Cape Cod beaches shrink, shift and disappear in places. Cases of heatstroke triple.
And every 10 years or so, a winter storm floods portions of Lower Manhattan, Jersey City and Coney Island with seawater.
The Northeast of recent historical memory could disappear this century, replaced by a hotter and more flood-prone region where New York could have the climate of Miami, and Boston could become as sticky as Atlanta, according to the first comprehensive federal studies of the possible effects of global warming on the Northeast.
"In the most optimistic projection, we still end up with a six- to nine-degree increase in temperature," said George Hurtt, a University of New Hampshire scientist and co-author of the study on the New England region. "That's the greatest increase in temperature at any time since the last Ice Age."
Commissioned by Congress, the separate reports on New England and the New York region explore how global warming could affect the coastline, economy and public health of the Northeast. The language is often technical, the projections reliant on middle-of-the-road and sometimes contradictory predictive models.
But the predictions are arresting.
New England, where the regional character was forged by cold and long, dark winters, could face a balmy future that within 30 to 40 years could result in increased crop production but also destroy prominent native tree species.
"The brilliant reds, oranges and yellows of the maples, birches and beeches may be replaced by the browns and dull greens of oaks," the New England report concludes. Within 20 years, it says, "the changes in climate could potentially extirpate the sugar maple industry in New England."
The reports' origins date to 1990, when Congress passed the Global Change Research Act. Seven years later, the Environmental Protection Agency appointed 16 regional panels to examine global warming, and how the nation might adapt. These Northeast reports, completed last fall, are among the last to be released.
The scientists on the panels employed conventional assumptions, such as an annual 1% increase in greenhouse gases in the atmosphere. They conclude that global warming is already occurring, noting that, on average, the Northeast became 2 degrees warmer in the last century. And they say that the temperature rise in the 21st century "will be significantly larger than in the 20th century." One widely used climate model cited in the report predicted a 6-degree increase, the other 10 degrees.
