Inversion Layer News Today

An ongoing fire is producing a plume of smoke that's combining with fog, held close to ground, under a temperature inversion to create this dangerous situation

In the 1950s, regulators knew every source of air pollution, from the incinerator to the automobile, had to be controlled. Polluting industries weren't happy.

Southern California's May gray has been stubborn. Here's an explanation. But be prepared for June gloom.

Is it just clean up time? >> reporter: were not at clean up time because this is an active fire zone. the fire fight continues in the areas that surrounded this area and for hot spots that still remain within the city limits or within the town limits. what were seeing is not much because, again, we continue to be under this inversion layer where the smoke just settles and rests in one place which is terrible, really terrible for air quality. county health departments as far away as the bay area ...

Little town there. what are officials telling you? >> reporter: fire officials say they caught a break this weekend because of the red flag winds that pushed the fire into town here died down before the weekend. an inversion layer formed. it all formed in one spot, there was nothing to move it. so it settled. it makes the atmosphere cooler, humidity rises, temperatures drop, and they can get a handle on it, because theres no wind to move the fire to a new front. you can finally see behind me, th...

Has a car in front of it or in the drive way. so thats kind of telling me that it hit so hard, people had no time. >> i mean, i understand its not just the flames and the wind, the smoke is also causing significant difficulties. >> yes and no. during the course of this fire, after that particular firestorm went through, we have whats called an inversion layer. the coal holds the smoke down close to the ground. sometimes we do have visibility issues, and that would hamper our aircraft efforts at ...

And those choices could improve air quality at the expense of climate or it could improve both climate and air quality at the same time. the decisions they make will be critical over the next five years and how that trajectory works. >> wow. it is getting -- the world is getting smaller and smaller and smaller. we are dependent upon everybody else. thank you. >> pleasure. create ideals conditions for the air in china. pedram has more on this. we were chatting last hour. this is a lot to do wit...

Diesel engine. it creates an inversion layer of air that raises ground temperature a couple degrees. >> its powerful for 10 to 15 acres. >> growers also warm the ground by saturating it with water. they must do that before the pipes freeze. >> putting moisture in the ground generates warmth. >> its a tricky job that he refuses to delegate to anyone else. >> i have a great crew with me, but no, hands on. you have to be out here. >> so far, despite temperatures in the low 20s, so good. >> you can ...

Around yosemite national park. were now told that it could be weeks before this is fully contained. some good news for one small community, though, as evacuation orders have been lifted bringing relief to those who are able to return home to their houses. listen. >> packing up and leaving your house and looking back at it -- [laughter] thats what gets you, you know? >> you wonder if youre going to see it again. >> right, exactly. martha: boy, how scary would that be? claudia cowan joins us live ...

Francisco. there has been ash detected on the top of the reservoir but the water comes from the bottom. officials say the water supply has not been tainted. the fire spread to 18 had,000 acres, its 20% contained which fire officials say its a good number, they feel confidence about stopping the spread into yosemite. yosemite national park 800,000 acres, 24,000 acres of yosemite burned so far, about 3% of the park, one change since yesterday and over the last camel of days. its been so smoky beca...