As the 2012 agricultural fire season progressed in Indochina, smoke blanketed the region and aerosol particulates increased to potentially unhealthy levels. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite captured this true-color image of the vast amount of smoke and haze hovering over the region on February 23, 2012.
The image is centered in northern Thailand, where thick ropes of gray smoke lie in each valley, obscuring the land except for the green lines of mountain ridges. To the west is Myanmar (Burma) and to the east is Laos. Fires also burn in Vietnam (far east) and southern China (northeast). Although the smoke is heaviest in valleys and near the red hot spots that mark heat from fires, no section of sky in this entire region is free of smoke.
On February 19, the Bangkok Post reported that the Public Health Ministry had begun to hand out 50,000 face masks to residents of the haze-shrouded northern provinces of Thailand. The masks were to be distributed to eight provinces where the PM10 (particulate matter level of up to 10 micrometers in diameter) were found to be higher than acceptable standards. These provinces were Phayao, Nan, Phrae, Mae Hong Son, Lamphun, Lampang, Chiang Rai, and Chiang Mai.
On February 23, the day this image was captured it was reported that the situation had clearly worsened, causing the local airport in Lampang to turn the runway lights on in daylight, to aid in the safe landing of aircraft.