Can smog be beneficial?
A new study says yes, sort of.
Tiny pieces of air pollution — also called fine particulates — contribute to human cases of asthma, lung disease, even premature death and therefore are a target for removal by state and federal air quality agencies looking to protect public health.
But researchers from the Jet Propulsion Laboratory in La Canada Flintridge and Caltech in Pasadena have discovered these same microscopic dirt balls fouling the air act as barriers that ricochet sun beams back into the atmosphere, blocking the rise in surface temperatures and possibly slowing global warming.
Known as aerosols, these microscopic pieces of diesel exhaust, dust, soot and factory emissions form what some dubbed “a warming hole,” meaning they create a cool spot over an increasingly warming Earth.
“I would never say air pollution is beneficial because obviously it is bad for human health. And I’m not going to say it has a positive effect, but it appears in some cases it slows down warming,” said Mika Tosca, lead scientist on the study released last week and published in the journal Remote Sensing in July.
Yes, there’s a catch.
The warming holes disappear once the concentration of pollution particles is reduced. Then, after that, surface warming accelerates, Tosca said. It’s like putting a movie on pause and then fast forward.
Tosca and her team began the study by noticing that temperatures in the Southeast United States — Mississippi, Alabama, Georgia and parts of Louisiana — had remained steady as compared to the rest of the world. In the 20th century, this part of the country saw no temperature rises, while the average temperature in the continental U.S. rose by almost 1 degree Fahrenheit.
Temperatures actually decreased in the Southeast at times but began to rise in the 1990s. From 2000 to 2015, the temperatures rose sharply, by 1.5 degrees Fahrenheit, higher and faster than the rest…