From fish migrations to stronger storms overwhelming aging infrastructure, global warming is already affecting life in Maine and other New England states in alarming ways, says a new federal report aimed at pressuring policymakers to take action on climate change.

Nationwide, the warming climate is producing deeper droughts in some areas and more frequent deluges in others. The report, released Tuesday, says that more severe heat waves, coastal flooding, massive wildfires and other trends underscore the need for local, state and federal action.

“Climate change, once considered an issue for a distant future, has moved firmly into the present,” says the report’s introduction.

At more than 800 pages and involving hundreds of scientists, the National Climate Assessment report is largely a synthesis of earlier research. The White House called it “the most comprehensive scientific assessment ever generated of climate change and its impacts across every region of America.”

By the end of the century, temperatures could be up to 5 degrees higher, even if the nation acts aggressively to reduce greenhouse gas emissions. It could be up to 10 degrees hotter if emissions are high, according to The Washington Post.

The higher the temperature, the more dire the impact. Extreme weather in the United States caused by climate change has increased in recent decades, the report said.

The decade starting in 2000 was the hottest on record, and 2012, the year Hurricane Sandy followed an epic summer drought, was the hottest ever recorded in the nation’s history, the report said. U.S. temperatures are 1.3 degrees to 1.9 degrees Fahrenheit higher now than they were in 1895, and most of that increase – 80 percent – occurred in the past 44 years, the assessment says.

Reaction to the study on Capitol Hill reflected the political polarization over climate change and the dim prospects for any effort to pass sweeping legislation in a divided Congress before November’s elections.

“It is just one more piece of evidence” of man-made climate change, said independent Sen. Angus King of Maine, who is among about two dozen Democratic and independent senators who are pushing the issue. “Eventually, I think the people who don’t want anything to be done are going to get worn down.”

Republican Sen. David Vitter of Louisiana said the report was supposed to be scientific but “it’s more of a political one used to justify government overreach” that will only hurt businesses and the economy, according to The Associated Press.

The report outlines effects on Maine and New England, including:

The spread of invasive plant and insect species. One potential victim is the moose, which faces greater infestations of ticks that survive milder winters.

More frequent heat waves. One study projected that northern New England communities near the Canadian border could eventually have 15 days a year when temperatures exceed 90 degrees. They now have fewer than five.

At the same time, the report says warmer summers will likely draw more tourists to Maine’s beaches.

The migration of commercial fish species northward as ocean water temperatures rise. The shift creates potential for the loss of historic cold-water fisheries, but opportunities for fishing for new species.

The Northeast’s sea surface temperatures rose by nearly twice the global average from 1982 to 2006, bringing warm-water species into New England waters as bottom-dwelling, cool-water species such as lobster and cod migrated farther up the coast.

Lobster fisheries off New York’s Long Island and in Connecticut have declined dramatically over the past decade, while Maine fishermen have had record catches. Some fishermen can adapt by diversifying, but sustained climate-related changes “may push these fishermen beyond their ability to cope,” the report says.

“Larger fishing boats can follow the fish to a certain extent as they shift northward, while smaller inshore boats will be more likely to leave fishing or switch to new species,” the report says. “Long-term viability of fisheries in the region may ultimately depend on a transition to new species that have shifted from regions farther south.”

The report says some states and communities are already responding to the perceived threats posed by global warming.

Nine northeastern states, including Maine, established the nation’s first cap-and-trade system to regulate the amount of carbon dioxide emissions from fossil fuel-burning power plants. The Obama administration has praised the Regional Greenhouse Gas Initiative, and is finalizing work on its national approach to power plant emissions.

The climate report also highlights Maine’s work to improve culverts – which carry storm runoff under roads, train tracks and footpaths or through embankments – in anticipation of climate change. Also, Maine’s permitting rules restrict the size and location of coastal development based on assumptions of a 2-foot rise in sea level within 100 years.

But the administration of Republican Gov. Paul LePage has been far less engaged on climate change issues than its predecessor, under Democratic Gov. John Baldacci. For instance, the LePage administration halted efforts to create a climate change adaptation plan begun during the Baldacci administration.

Bob Kates, a professor of sustainability science at the University of Maine’s Climate Change Institute and co-author of the report’s section on northeastern states, said many people perceive beach erosion as the most pressing threat for Maine’s coastal communities. In fact, officials in coastal communities are often more concerned about aging or inadequate culverts to deal with the increasing number of severe storms.

“The culvert problem is real,” said Kates, who has worked with a Sustainability Solutions Initiative at UMaine that helps communities develop long-term plans for culverts.

U.S. Rep. Chellie Pingree, D-Maine, cited the report’s findings on fisheries to call for more aggressive policy action on climate change.

“The heart of the lobster fishery keeps moving east along the coast,” Pingree said in a prepared statement. “This means that communities that have traditionally depended on lobstering will start to lose out. And an even bigger concern is the risk of warming temperatures contributing to a rapid, overall decline in the fishery, not to mention the threats to groundfish and shrimp.”

U.S. Sen. Susan Collins, a Republican from Maine who has resisted efforts by her party colleagues to prohibit regulation of greenhouse gases, said Tuesday’s report “reinforces my belief that climate change is a threat to our communities and a challenge that requires global solutions in order to reduce greenhouse gas pollution.”

“By promoting clean-energy alternatives and efficiency, we can reduce pollution, advance the goal of energy independence for our nation, and spur the creation of new manufacturing jobs in our country rather than in China,” Collins said in a prepared statement.

King, meanwhile, said he doesn’t expect anything “comprehensive” to emerge from Congress this year, but lawmakers could agree on smaller pieces of climate change legislation. In his experience as governor and senator, he said he knows that debates over contentious issues can drag on for years, only to reach a sudden tipping point.

“I think it is going to happen in the foreseeable future, but whether that’s this year or next year I don’t know,” King said. “In the meantime, I think my job is to continue to warn people that this is an impending problem that is going to have a real impact.”

Kevin Miller can be contacted at 791-6312 or at:

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