Air Quality conditions today are very similar to those reported this week. PM2.5 concentrations were good in most of the nation except in the Great Lakes, Northwest regions and California. In California unhealthy levels for sensitive groups were reached. Ozone levels were good throughout the entire country. Regional Tropospheric NO2 columns from OMI reported high NO2 level over a significant area in the northern states (top right). HMS detected different fires in several regions; however, no significant smoke was seen so far.
With reference to the smoke over Alaska posted initially by Ruben last week (November 7th), Earth Observatory has posted a couple of pictures acquired by MODIS were thick smoke plumes can be observed in that area that proves the initial guess.
According to Earth Observatory : Dust plumes hovered over the ocean off southwestern Alaska in early November 2012. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite observed dust over Bristol Bay on November 6, and dust over the Gulf of Alaska on November 7. While the dust over the Gulf of Alaska could easily be traced to sediments along the Copper River, the source of the dust over Bristol Bay was not as obvious (bottom).