Boston could spend nearly three months a year sweltering in 90 degree heat by the year 2100 -- much more than the city currently experiences -- if enough isn't done to reduce greenhouse gas emissions, a new climate report warns.
And along with temperatures rising by as much as 10 degrees, the Greater Boston Research Advisory Group report released Wednesday by UMass Boston warns of rising sea levels and stronger storms coming for the Boston area if emissions levels hold steady or get worse.
"To think we've caused this much change in our climate is astounding," UMass Boston climate adaptation professor Paul Kirshen, one of the authors of the report, told The Boston Globe. "We've already done a hell of a lot of damage, and this report emphasizes the need to get to net zero emissions."
While the impacts of climate change are broadly accepted by the scientific and public policy communities, the local impacts aren't often laid out in detail. The Greater Boston Research Advisory Group's analysis looks at the impacts of climate change on 101 cities and towns in the Boston metropolitan area.
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The increase in temperatures could be as high as 10 degrees by 2100, leading to up to 80 days of the year with at least 90-degree weather in Boston, the report found; the area currently has about 10 days where the thermometer hits 90. That would affect local industries, including cranberry growers and winter sports; raise residents' energy costs by up to 12%; and hit especially urban heat islands especially hard, exacerbating the already increased risk of death.
If greenhouse gas emissions continue to increase, Boston Harbor could have nuisance flooding about half the year by 2050, up from about 15 days a year now. And the intensity of the region's regular rainfall could lead to increase flooding across the whole area, the report notes.
The intensity of the impacts projected in the report depends on several factors, including whether and how much greenhouse gas emissions can be limited. But the authors note that, even if climate change is mitigated, its effects could still be felt.
Boston Mayor Michelle Wu said in a statement that the report's analysis helps the city "make the most informed decisions" about protecting
"We know that the window of time to act on climate change is closing quickly and it is critical to align our policies and programs with the latest science," she said. The GBRAG report analyzes Boston's climate risk projections so we can make the most informed decisions on how to protect our communities from unavoidable impacts while mitigating emissions that contribute to climate change.”