The central valley of California has been having a particle air pollution episode from December 2 to today. Towns like Fresno, Modesto, the Sacramento area, Chico and Bakersfield have been experiencing PM 2.5 air pollution in the Code Orange (unhealthy for sensitive groups) to Code Red (unhealthy for everybody) range during this period.
San Jose and Livermore had at least a day of these conditions also during mid-episode.
Do you like to breathe air that you can see?
Here is the view from Sequoia-Kings Canyon National Park in real time; at 12:45 PM PST, the area around Visalia and Exeter California are completely obscured; note the heavy haze layer aloft with a top at about 3-5000 feet over the central valley.
Real Time:
http://www2.nature.nps.gov/...
Here is a 1 PM, December 5 static view for those who might see this tonight (real time webcam goes dark for the night)
http://www2.nature.nps.gov/...
As I write at 4:15 PM today, Fresno and Bakersfields are under Code Orange conditions:
http://www.airnow.gov/...
Here is the Sequoia-Kings Canyon webcam view on December 2, 2006:
http://www2.nature.nps.gov/...
But now.....here is a different, even more interesting view of the December 2, 2006 episode from space.
Here is NASA
MODIS satellite imagery from that day showing a extensive
PM 2.5 haze cloud covering the California central valley area
east of the San Francisco area.
http://rapidfire.sci.gsfc.nasa.gov/...
[pan down the coastline until you see the
familiar shape of San Francisco bay area....
...and then pan to the right (east) to see the
extensive haze area SSE of Sacramento.]
Unfortunately, imagery was taken at a different time
further south down the central valley so conditions
further south are not as readily apparent.
Both Modesto and Fresno went to a Code Red PM 2.5
condition that day.
http://www.airnow.gov/...
Sacramento map AIRNOW imagery also indicates a
site just west of the city also went Code Red on 12/2