Warmer climates creeping northward threaten Long Island

If scientists studying climate change are on the mark, Riverhead farmer Phil Schmitt ought to consider the weather in Virginia when planning his crop list in coming decades.

Warmer climate zones have been creeping northward in recent years and could transform Long Island to conditions much nearer those of Virginia in 30 years, scientists say. The number of days above 90 and 100 degrees has increased, along with major rain events and rising sea levels - all connected to climate change that is expected to continue.

Federal and state officials say coastal communities need to start planning now to protect buildings, wetlands, lowlands and barrier islands. That could mean limiting development in low-lying areas and elevating existing homes and infrastructure including roads and sewage treatment plants. Public health experts caution warmer, wetter weather could also bring heightened risk of West Nile virus and other mosquito-borne diseases.

By 2100, the average annual temperature for New York is expected to increase between 6.6 and 9 degrees, depending on the effectiveness of efforts to curtail emissions, according to a 2009 report by the New York City Panel on Climate Change. The number of days above 90 degrees could triple, from an average of 14 a year to up to 45 by 2050. By 2080, sea levels in and around Manhattan are expected to have risen 12 to 23 inches, according to the report. All predictions about the impact of climate change are variable, and the range of effects depends on the success of efforts to curb greenhouse gas emissions. Still, there's little debate that effects are already being felt.

Among current trends scientists and others cite:

Grapes in Long Island's expanding vineyards are consistently budding weeks earlier, which could risk damage to the fruit of the vines from late frost, East End farmers and agricultural experts say.

Crops are becoming more vulnerable to proliferating pests, requiring better management and more chemical treatments, says Cornell University.

Rising seas pose acute problems in coastal regions, particularly during storm surges, and insurance companies have taken note, according to an EPA official.

Rising water temperatures are chasing once-thriving species such as lobsters and winter flounder from local waters, according to Stony Brook's Marine Sciences Research Center.

Higher temperatures have encouraged proliferation of jellyfish, sea squirts and starfish, in some cases pressuring other species, according to Citizens Campaign for the Environment.

For Schmitt, who has doubts that global warming is at fault, growing lettuce has become particularly challenging in recent years - 90 percent of his 2009 spring crop was wiped out by torrential rains and humid weather. (Experts say extreme rain events are part of the new norm of climate change.)

One state scientist said there's no doubting the trend.

"Spring is definitely coming earlier," said David Wolfe, professor of horticulture at Cornell University who has served on state panels examining the impact of warming on agriculture. The northward creep of southern climate zones brings with it challenges and opportunities, he said. With warmer weather and more moisture, farmers should expect an extended growing season, and more diseases, weeds and insects.

On the waters, the warming trend might cause a northward shift in the habitat range for cold-water species. That could mean the end of lobsters in Long Island Sound, said David Conover, dean and director of the Marine Sciences Research Center at Stony Brook University.

And as waters warm, they are also expected to continue rising. "Long Island is particularly vulnerable to sea level rise, and I think this is going to be a much bigger problem than people realize," said Judith Enck, regional administrator for the Environmental Protection Agency.

"I think in our generation we're going to be looking at impacts from sea level rise. . . . Increased storm surge, flooding," she said.

Long Islanders in coastal areas face loss of home insurance or prohibitive premiums. "The question of floods not being covered unless you have flood insurance is going to be a big one," said Neal Lewis, executive director of the Sustainability Institute at Molloy College. "I think a lot of Long Islanders will have to live with that risk."