Thick fog and haze obscured much of the North China Plain from view when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite flew over on October 7, 2004. The fog has been clinging to the landscape for the past several days. In the top center of the image, the fog creeping up the river valleys cut through the Jundu Mountains, tracing out the contours of the land as it clings to the lower elevations. MODIS also detected a few scattered fires, which have been marked with red dots.
Incomplete burning of carbon-based fuels like coal and wood leads to a build-up of haze in eastern China, where mountains and weather patterns can trap it for days at a time. This Terra MODIS image is a comparison of a hazy day and a relatively clear day in February 2005.