Carbon Monoxide - 2000

Carbon monoxide is known as "The Silent Killer" because it is a colorless, odorless, tasteless gas that is poisonous to humans and other oxygen breathing organisms. It is also naturally occurring in the atmosphere. Only in high concentrations is carbon monoxide deadly. At the Earth's surface the concentration of carbon monoxide is 100 ppb (parts per billion), however, in urban areas it can get up to 10 ppm (parts per million) or 100 times higher. One of the main anthropogenic sources of carbon monoxide in the atmosphere is emissions from automobiles. In areas with heavy traffic the carbon monoxide can be measured at 50 ppm. The natural sources of carbon monoxide include volcanoes and brush burning. Between the anthropogenic and natural sources, scientists estimate that the annual production of carbon monoxide is 2-5 gigatons.

This dataset tracks the carbon monoxide in ppb at 500mb (about 12,000ft) from March 1, 2000 through December 31, 2000. The measurements were made using MOPITT, Measurements of Pollution in the Troposphere, an instrument on the NASA satellite Terra. The lifespan of carbon monoxide in the atmosphere is several months. This lifespan is shorter than the time it takes the gas to completely mix through the atmosphere, so the carbon monoxide can be seen moving in concentrated masses. Often the carbon monoxide from one continent has an impact on other continents down wind from the first. Carbon monoxide is one of six pollutants regulated in the United States and other countries. It is not a direct greenhouse gas, but it reacts with other chemicals in the atmosphere that would otherwise destroy methane and ozone. Therefore, carbon monoxide indirectly leads to an increase in the greenhouse gases methane and ozone. There is a distinct difference in the concentrations of carbon monoxide in the northern hemisphere versus the southern hemisphere. This is likely due to the fact that many more people live in the northern hemisphere than the southern hemisphere. The carbon monoxide coming from Africa and South America is largely due to agricultural burning.