Climate change could alter many aspects of life in the Northeast, according to a new report.
Jennifer Weeks
New England’s output of signature products like maple syrup, cranberries, and cod could fall sharply by 2100 due to climate change, according to a report released yesterday by the Cambridge, MA-based nonprofit group, Union of Concerned Scientists (UCS). But reducing greenhouse gas emissions by about 3 percent per year over the next several decades could lessen these impacts by roughly half.
The study draws on peer-reviewed research by some 60 experts from universities, government agencies, and nongovernmental organizations (mostly in the Northeast) to predict specific impacts of rising temperatures in a wide range of areas, including agriculture, air quality, and weather events, under two different scenarios of varying greenhouse gas emission levels. “Under the high scenario, we lose the character of seasons and climate in New England that we’ve grown up with,” says University of New Hampshire associate professor Cameron Wake, co-leader of the project’s climate modeling team.
The report, Confronting Climate Change in the U.S. Northeast_, is the second from the Northeast Climate Impact Assessment (NECIA), a collaboration between the Union of Concerned Scientists and other researchers. The first reportfinal.pdf in October 2006 used three global climate models to forecast regional temperature changes through 2100. If today’s high-emission path continues, it estimated, annual average temperatures will rise 6.5 to 12.5^o^F. Sharp cuts in greenhouse gas emissions would reduce this warming to between 3.5 and 6.5^o^F.
The newest report predicts that Boston’s 100-year flood zone—the maximum flood elevation likely to occur once a century—will stretch from Faneuil Hall to North Station by 2100 in the high-emission scenario, in which greenhouse gas levels continue to rise at the current rate. Today, that flood zone covers limited areas along the waterfront east of Atlantic Avenue.
Hot and smoggy
Rising temperatures will likely produce more summer heat waves, the study says. From 1961 through 1990, temperatures in Boston exceeded 100^o^F on average once a year. By the late 21st century, NECIA projects, the mercury will hit triple digits six to 24 days annually.
With hotter temperatures come higher levels of ground-level ozone, the main component of smog. The report estimates that the number of days when ozone concentrations exceed federal limits in Boston, Buffalo, New York City, and Philadelphia will increase by 50 percent in the low-emission scenario and quadruple in the high-emission scenario.
“They’ve done a great job of showing how climate change alone will affect air quality,” says Praveen Amar, director of science and policy at Northeast States for Coordinated Air Use Management, a Boston nonprofit that provides research support to Northeast state air regulators. However, Amar says, the actual forecast is more complicated because regulations now in place will reduce air pollutants that contribute to ozone formation over the next several decades. “This report assumes that traditional pollutants will stay constant,” he says.
Other impacts predicted by NECIA include lower yields of crops that need cold weather to flourish, including cranberries and many apple varieties. Warmer temperatures will extend the northern ranges of insect pests like the hemlock woolly adelgid and invasive weeds like kudzu. Suitable habitat for most of the region’s tree species will shift 350 to 500 miles northward by 2100. Ocean waters south of Cape Cod will become too warm for cod, a major New England fishery. And spruce-fir forests could virtually disappear under the high-emission scenario, along with associated animals such as snowshoe hares and Canadian lynxes, according to the report.
Next steps
The study recommends reducing greenhouse gas emissions worldwide to 80 percent below current levels. That would mean cutting emissions by a little more than 3 percent annually, which would put the Northeast well on track to reach the 80 percent goal by about 2050.
“We’re far from helpless. We have the intellectual capital to lead on this issue,” says UCS president Kevin Knobloch, citing initiatives such as a regional agreement in the Northeast to cap carbon dioxide emissions from power plants and a new Boston building code requirement for large projects to meet “green” building standards.