Smoky Anchorage has the worst air quality in the U.S.

It's been the city's smokiest summer on record.
 By 
Mark Kaufman
 on 
Smoky Anchorage has the worst air quality in the U.S.
The McKinley Fire burns north of Anchorage on August 18, 2019. Credit: Maureen Clark / AP / Shutterstock

Anchorage's smoky summer won't relent. As of Tuesday morning, the most populated city in Alaska had the worst air quality in the nation, according to the World Air Quality Index.

A number of late-season wildfires have perpetuated Anchorage's hazy summer, which has been the city's smokiest summer on record. On Tuesday morning, smoke levels ranked as "unhealthy," with an air quality index of 175.

Warming Alaska -- the fastest-changing state in the U.S. -- has been primed for wildfire this summer, after the Last Frontier experienced record-breaking heat waves and its hottest July ever recorded (reliable temperature data in Alaska goes back nearly a century, to 1925). The area burned this summer, while not record-breaking, still amounts to one of Alaska's largest documented fire years, having scorched some 2.44 million acres, an area about twice the size of Delaware.

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Original image has been replaced. Credit: Mashable

It hasn't just been warm in the Anchorage region. It's been dry. Summer rainfall has been about a third to half of average, noted Rick Thoman, a climate specialist at the Alaska Center for Climate Assessment and Policy. So conditions have been ripe for flames.

Smoke is expected to persist in the region through Wednesday.

Beyond Alaska, the greater Arctic -- a region warming twice as fast as the rest of the planet -- has had a historic wildfire year. Fires have been atypical in Siberia, with hundreds of separate blazes. "The unusual thing about this year has been the number and distribution of fires north of the Arctic Circle in Siberia, Alaska, and more recently in Canada," Mark Parrington, a senior scientist at the European Union's Copernicus Atmosphere Monitoring Service, told Mashable at the end of July.

The World Meteorological Organization called the high Arctic wildfires "unprecedented." In June alone, wildfires released more carbon into the atmosphere than Sweden does in an entire year. 

On a related note, last week the National Oceanic and Atmospheric Administration confirmed that the month of July was the hottest month on Earth in 140 years of record-keeping. Increased temperatures boost the odds for fire weather, and consequently, blazes.

On Monday, the National Weather Service said that, for the first time since June 20, Anchorage dropped below 50 degrees Fahrenheit, marking the second-longest streak on record.

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Mark Kaufman
Science Editor

Mark was the science editor at Mashable. After working as a ranger with the National Park Service, he started a reporting career after seeing the extraordinary value in educating people about the happenings on Earth, and beyond.

He's descended 2,500 feet into the ocean depths in search of the sixgill shark, ventured into the halls of top R&D laboratories, and interviewed some of the most fascinating scientists in the world.

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