MIT's Matthew Rigby and Ronald Prinn, the TEPCO Professor of Atmospheric Chemistry in MIT's Department of Earth, Atmospheric and Planetary Science, state that this imbalance has resulted in several million metric tons of additional methane in the atmosphere. Methane is produced by wetlands, rice paddies, cattle, and the gas and coal industries, and is destroyed by reaction with the hydroxyl free radical (OH), often referred to as the atmosphere's "cleanser."Methane accounts for roughly one-fifth of greenhouse gases in the atmosphere, though its effect is 25x greater than that of carbon dioxide. Its impact on global warming comes from the reflection of the sun's light back to the Earth. Methane is broken down in the atmosphere by the free radical hydroxyl (OH), a naturally occuring process. This atmospheric cleanser has been shown to adjust itself up and down periodically, and is believed to account for the lack of increases in methane levels in Earth's atmosphere over the past ten years despite notable simultaneous increases by man.
Prinn has said, "The next step will be to study [these changes] using a very high-resolution atmospheric circulation model and additional measurements from other networks. The key thing is to better determine the relative roles of increased methane emission versus [an increase] in the rate of removal. Apparently we have a mix of the two, but we want to know how much of each [is responsible for the overall increase]."
The primary concern now is that while the collected data in 2007 reflects a simultaneous world-wide increase in emissions, how relevant are any of the data findings at this late date? (Daily Galaxy)
