Rising oceans could inflict coastal harm NRCM scenarios depict need to reduce greenhouse gases

An environmental organization predicted Tuesday that rising ocean levels tied to global warming could submerge tens of thousands of acres along coastal Maine, severely damaging popular oceanfront communities and inflicting “incalculable” harm on local tourism.

Natural Resources Council of Maine representatives said that, based on their calculations, 20,000-plus acres and 58 miles of roads in 20 towns from Kittery to Beals could end up underwater if sea levels rose about 3 feet.

And that is under the optimistic scenario.

If sea levels rose 20 feet – a real but unlikely possibility in the coming centuries, according to some scientists – the Cranberry Isles could shrink by 30 percent. Downtown Portland, meanwhile, would lose more than 1,000 acres, including part of Commercial Street. An estimated 128,000 acres all along the coast would be submerged.

While NRCM’s press release described downtown Portland being “wiped out” and Bath Iron Works being “ruined” by rising sea levels, a representative acknowledged in an interview that most of the scenarios laid out in the report would happen gradually over decades or even centuries.

But they said the report should serve as a wake-up call to state and local officials, businesses and average citizens about the need to reduce greenhouse gas emissions.

“It’s something that’s preventable,” said Dylan Voorhees, the group’s clean energy director. “We wanted to take this sense of urgency and do something with it.”

Working with students from Colby College’s geographic information systems program, NRCM produced a number of maps showing how popular coastal communities would be affected by sea level rises of about 3 feet over several decades or 20 feet likely over centuries.

Faculty from the University of Maine’s Climate Change Institute provided scientific input to NRCM.

The town of Tremont on Mount Desert Island, for instance, would lose 371 acres under the optimistic scenario and more than 1,500 acres – or 14 percent of its land mass – if waters rose 20 feet. Cranberry Isles would actually gain islands under the 20-foot scenario because many of the lower-lying areas of the larger islands would be submerged.

Vinalhaven and Deer Isle in Penobscot Bay would also shrink considerably with the current locations of schools, fire departments and libraries ending up underwater.

President Bush’s family home on Walker’s Point near Kennebunkport would be submerged by a 3-foot rise while the entire peninsula would be below sea-level if waters rose 20 feet. The Bush family compound’s inclusion in the report was no coincidence.

Environmental groups have assailed the Bush administration for refusing to go along with the international Kyoto treaty on cutting global warming emissions. Voorhees said Walker Point was included in the report to encourage the president to do more to curb global warming.

While global warming remains a divisive political issue, there appears to be an emerging scientific consensus worldwide that human pollution from smokestacks, power plants and vehicle tailpipes are driving up atmospheric temperatures.

Gordon Hamilton, an associate research professor at UMaine’s Climate Change Institute who advised NRCM, said the group’s predictions for coastal Maine were based on scientifically realistic sea level rises.

He called a 3-foot rise during the next generation to 50 years a “very reasonable scenario.” A 20-foot rise over the next 400 or so years is more unlikely but not impossible, he said.

Scientists predict that ocean levels could rise 20 feet if Greenland’s or East Antarctica’s ice sheets melt or break away. Hamilton said researchers worldwide have documented alarming changes in both Greenland and Antarctic ice sheets.

“I would not be totally surprised if by the time I retired from my job in Orono there would be a 3-foot rise in sea levels, and that’s a lot,” the 40-year-old researcher said. “I think it’s time people started paying attention to these possibilities … because the sooner we start, the better prepared we will be.”

Terrance Joyce, director of the Ocean and Climate Change Institute at the Woods Hole Oceanographic Institution in Massachusetts, predicted that sea levels would rise about 1 foot or slightly more during the next century.

But Joyce, who was not involved in the NRCM study, agreed that a 20-foot rise is possible if the ice sheets melt in Greenland and Antarctica. In any case, Terrance said modeling helps people near the coast understand how global warming could affect their property years or generations in the future.

NRCM’s Voorhees pointed out that many scientists now consider a 3-foot rise as falling in the “middle-range.”

“Twenty feet is very dramatic, and the impact would be immense,” he said. “But it’s a possibility that would be irresponsible for us not to consider.”