Smoke from the Rim Fire choked Yosemite National Park during the busy Labor Day weekend. Air quality reached unhealthy levels from Yosemite to the San Joaquin Valley, according to an air quality alert from the National Weather Service. People were advised to avoid strenuous outdoor activity or to remain indoors because fine particles in smoke can irritate the eyes and respiratory system and aggravate chronic heart and lung disease.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this true-color image of the Rim Fire and its smoke on August 31, 2013. Red boxes outline the active fire areas. The smoke is brown and smooth in texture compared to the bright white clouds; it was thick enough at the time to entirely block the view of the ground from space. The smoke is brown and smooth in textured compared to the bright white clouds. It was thick enough at the time to entirely block the view of the ground from space.
For people in the park, the smoke obscured Yosemite’s normally pristine views. Though smoke had the greatest impact on local communities, the carbon monoxide from the plume has been tracked across most of North America. By September 6, the Rim Fire had burned 246,350 acres (385 square miles), making it the third largest fire in California history and the largest fire this in the United States so far in 2013. On that date, the fire was 80% contained, but fire officials warned that the fire intensity was expected to increase in the next day, as unburned areas within the control lines are expected to ignite. Hotter and drier weather is expected to persist through September 8, increasing the chance of spotting or embers crossing containment lines.