Massachusetts' air quality predicted to backslide due to climate change

After decades of progress in the U.S. toward cleaner air, climate change-related events will set back gains in parts of Massachusetts through 2054.

Driving the news: At least six counties in Massachusetts — primarily in Western and Central Massachusetts — over the next 30 years will see an increase in "bad air quality" days per year, when pollution is above 100 on the air quality index , per new research from the nonprofit First Street Foundation.

• Hampden, Hampshire and Worcester Counties may see the number of "bad air quality" days double from two to four in that time frame, thanks in part to smoke from wildfires thousands of miles away.
• Boston and surrounding cities may not see an increase in the number of "bad air quality" days, at least in that time frame.

Why it matters: These regions are now expected to have fewer bad air quality days than they did 15 years ago, but climate change and the increased likelihood of wildfires as far away as Canada stand to reverse those gains, per First Street's research.

Flashback: The smoke from Canadian wildfires last year sparked air quality alerts for millions of people in the northeast, including in Central and Western Massachusetts .

The big picture: The population exposed to "dangerous" days on the air quality index is likely to grow to 11.2 million, a roughly 13% increase, by 2054.

• A 27% gain in the population exposed to "hazardous" days on the AQI is likely by then, the report found.
• While the West, particularly Washington, Oregon and California, are projected to see some of the worst air quality impacts, chiefly from wildfire smoke, other parts of the country are also vulnerable from heat-induced jumps in ozone concentrations.

Between the lines: Pollutants from cars and factories could be targeted by regulations over the past few decades (and the EPA wants to tighten some further ), but climate-related deterioration in air quality is a much tougher problem to solve, Jeremy Porter, head of climate implications at First Street, told Axios in an interview.

• Instead of national regulations, climate action requires global emissions cuts, and even sharp declines in greenhouse gas emissions may not alter trend lines for the next few decades.

What they're saying: "The climate penalty, associated with the rapidly increasing levels of air pollution, is perhaps the clearest signal we've seen regarding the direct impact climate change is having on our environment," Porter told Axios via email.

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