Most of the US has passable air quality on the weekend. There is an area of code yellow PM2.5 and a small area of code orange ozone in Southern California. The ozone loop lower left shows the spot of elevated ozone in LA. There is one feature in the east which looks like dense smoke but it appears to be cloud or fog over Kentucky. The VIIRS Aerosol Optical Depth today shows it in RGB so it did not pass the cloud mask.
Mike Fromm of NRL is always on the lookout for high altitude smoke and he sent along a mystery today from the pyroCb webpage. There is a high altitude layer in the NSF HSRL lidar in Boulder Colorado (Ed Eloranta's data). That layer looks to me like small spherical droplets and would indicate a volcanic source. There was, however, no recent high altitude explosive eruption noted on the Alaska Volcanic Observatory page. The OMI SO2 columns show that there was an eruption of the Pavlov volcano in the Aleutians on June 3 but the SO2 dissipated by June 6.
Update: Sunday June 15, 20:30 EDT
Haze continues in Southern California but the new story is elevated PM2.5 in the US Southeast. The GASP loop shows elevated AOD off the coast of Texas and it is believed that this is Saharan dust. The CALIPSO processing has not caught up from their downtime last week and June 12 is the last set of CALIPSO images. Two images however show a pulse of Saharan dust from Thursday's overpasses. This is likely the elevated AOD in Texas.
Posted by Ray Hoff at June 14, 2014 10:03 PM