Cape Cod Times: Study finds rapid warming in Northeast waters

Study finds rapid warming in Northeast waters

 The Cape Cod Canal, Buzzards Bay and the Massachusetts Maritime Academy are pictured during the canal's 100th anniversary celebrations. A new study from NOAA indicates that area waters are warming up at a much faster rate than scientists had previously thought. Steve Heaslip/Cape Cod Times

By Mary Ann Bragg
Cape Cod Times

Posted Jan. 15, 2016 at 3:24 PM 

WOODS HOLE — The ocean off Cape Cod is warming at a rate more than double what prior modeling predicted, according to a report released Thursday by the National Oceanic and Atmospheric Administration.

The finding by researchers at the federal agency matches what has already been recognized locally over the past 10 years, said the report's lead author, fisheries scientist Vincent Saba.

The climate change computer model used in the research has a greater resolution than models used to predict ocean temperature changes for the latest U.N. Intergovernmental Panel on Climate Change report from 2013, Saba said.

Read more about how climate change is affecting Southeastern New England:SouthCoastToday.com/Climate.

The IPCC report used data from more than two dozen climate change computer models from laboratories around the world, all of which tend to be less precise than the more refined computer model used by NOAA, Saba said.

“It is like comparing an old standard definition television screen to today’s ultra high definition screens,” he said.

The more refined computer models are expensive to run, and very few are used throughout the world, he said.

The model developed by NOAA scientists has incorporated the complex seafloor terrain on and near the U.S. continental shelf in the Northeast, such as Georges Bank, east of Cape Cod, which other less-refined models have not, Saba said. The model also incorporated regional current patterns such as the position of the Gulf Stream, he said. The result is that the predictions of the more precise model appear to match the warming of local seas, a well-known phenomenon within the region but under-estimated by global computer models, he said.

The NOAA model estimates that with a doubling of carbon dioxide in the atmosphere over a 70-year period, the Gulf of Maine would warm by as much as 3 to 4 degrees Celsius, or 5.4 to 7.2 degrees Fahrenheit, about twice as fast as what less-refined models predict, the study says. The model suggests ocean temperatures off New England would warm nearly three times faster than the global average, according to the study.

“What we’re projecting for the future seems to be on par with what we’re seeing today,” Saba said. “Prior climate change projections for the region may be far too conservative.”

The report was published online in December in the Journal of Geophysical Research-Oceans, which is published by the American Geophysical Union. The refined model and others used for comparison were developed at a NOAA laboratory in Princeton, New Jersey.

The warming of waters in the Gulf of Maine has changed the distribution and composition of species in the region, and the new predictions of greater warming “will cause more extreme effects on the ecosystem,” according to the report.

Ocean researchers and conservationists on Cape Cod as well as the commercial fishing community have already seen a warming of seas that exceeds the global average, Center for Coastal Studies President Richard Delaney said. Delaney represented the center at the Paris climate talks in December during a day-long event to raise awareness of how oceans are linked to climate change.

“It certainly reinforces some of the early studies that suggested the same thing, that North Atlantic waters off Massachusetts will have an enhanced rate of ocean warming that exceeds the global average,” Delaney said Thursday.

One documented change in local ocean habitat due to warming waters is the apparent movement of cod north and east to deeper, colder water, said Delaney, who had not read Saba's research. Less well-documented is the movement of microscopic marine life such as plankton that serves as food for fish and whales, he said.

“There are going to be profound effects on ecosystems,” said biologist Barbara Brennessel, a member of a working group on the impact of climate change on shellfishing in Wellfleet Harbor.

The Wellfleet group has just released its findings on a new website: wellfleet.seri-us.org.

“Species that inhabit warming climates are going to be in our area,” Brennessel said. “There’s probably going to be an increase in invasive species that normally colonize warmer climates. We’re certainly expecting to see a change in oyster diseases. We already know that vibrio is a big concern.”

West Barnstable bluefin tuna fisherman Eric Hesse said Thursday the fishery has changed dramatically over the last 15 to 20 years, with what appears to be a strong correlation with warming waters. The largest fish, traditionally seeking out the coldest water, now stay around Cape Cod less frequently, Hesse said.

“We get a crack at them in early June and into July and then we start to see an influx of smaller fish,” he said. “Then by August it’s all the fish that used to swim around off the mid-Atlantic.”

There are also fewer and fewer ice seals from Canada found among the stranded marine mammals attended to by the International Fund for Animal Welfare, based in Yarmouth Port, Marine Mammal Rescue and Research Manager Brian Sharp said.

“We do note differences,” Sharp said.

In addition to predictions for warming of ocean temperatures over time, the more refined NOAA model predicted a more substantial increase in salinity as well, according to the study. Both the increase in temperature and salinity are associated with a northerly shift of Gulf Stream-associated waters, a retreat of the northern Labrador Current and a mixing of cold fresher water with warm, saltier water, according to Saba.

http://www.southcoasttoday.com/article/20160115/NEWS/160119591/101061/NEWSLETTER100