A menacing air in the Central Valley
http://www.latimes.com/local/la-me-central-valley-air-20140125,0,7934435.story
The downtown Fresno skyline, cloaked in thick haze, on Jan. 17. The amount of fine particles known as PM-2.5 in the air is now so high that even otherwise healthy adults are at risk.
A menacing air in the Central Valley
By Diana Marcum
January 24, 2014, 4:56 p.m.
FRESNO On bad-air days here in the Central Valley, school officials hoist red flags to warn parents and pupils that being outside is officially deemed unhealthful for all groups.
This winter, though, the most polluted on record, schools have not only raised red flags. On several days, they have had to send out notices saying the red flags should really be purpleindicating very unhealthful air if only they had them. But such warnings have been be so rare that schools don't even have the flags designating the most extreme conditions.
Of course, parents could just look at the sky itself.
From Stockton to Bakersfield, a haze of chemical-laced particles has tinted the air a rusty gray all winter. In the evenings there's a charcoal stripe across the horizon. The Sierra Nevada hasn't been visible for more than a month.