Thick haze accumulated over China for most of March 2007. Besides pollutants visible to human eyes, the haze contained substantial amounts of carbon monoxide. This image shows carbon monoxide measurements from March 1-27, 2007, as recorded by the Measurements of Pollution in the Troposphere (MOPITT) sensor on NASA’s Terra satellite.
In this color-coded image, colors indicate the average number of carbon monoxide molecules in the lower atmosphere. Dark blue indicates none. Deep red indicates 400 carbon monoxide molecules per ten quadrillion total molecules in a one-square-centimeter column of atmosphere. This image shows some of the mildest concentrations over central Asia, and some of the heaviest concentrations over India, Southeast Asia, the South China Sea, and the Sea of Japan. Wind often blows haze eastward over the ocean.
Carbon monoxide is a colorless, odorless gas. Because the gas results from combustion, it is a good indicator of urban and industrial pollution as well as fires. The high carbon monoxide concentrations observed by MOPITT in March 2007 were likely due to multiple sources, including pollution across China’s eastern coastal plain and fires in Southeast Asia.
NASA image created by Jesse Allen, using data provided courtesy of the National Center for Atmospheric Research (NCAR) and the University of Toronto MOPITT Teams.
The conspicuous haze over China in mid- to late October 2007 not only obscured the view of the land surface. It also contained substances harder to detect but just as troublesome. Odorless, colorless, and toxic, carbon monoxide can be lethal in large amounts. Additionally, it acts as a precursor to smog and ground-level ozone.