10-10-2005 - Earth

sagar: Author=’Marc Airhart’ program=’4663′ video=”Rice paddies in Yunnan Province, China. Rice farming is one of several human activities that release methane, which is thought to contribute by as much as a third to all climate warming from greenhouse gases. (Changsheng Li)_JB:_ This is Earth and Sky. Most climate scientists agree that one of the largest contributors to global warming is carbon dioxide – or CO2.

_DB:_ Now a study has shown that methane might be responsible for a third of all climate warming from greenhouse gases. “Dr. Drew Shindell”:http://www.giss.nasa.gov/staff/dshindell.html is a climatologist at NASA’s Goddard Institute for Space Studies in New York. He and his colleagues used computers to determine the impact of different gases on Earth’s climate. He said methane’s effect is now known to be greater because some methane reacts with other chemicals to produce yet another greenhouse gas – ozone.

_JB:_ Some methane in our atmosphere is released by bacteria in wetlands. But much of it comes from human activities such as livestock farming, oil and gas drilling, rice farming and landfills. Environmental treaties have focused on curbing CO2 emissions as a way to reduce global warming. But Drew Shindell thinks we should also focus on methane.

_Drew Shindell:_ Cleaning up methane gives you a reduction in worldwide ozone in the lowest level where it’s a toxic respiratory irritant for people and bad for crop yield and ecosystems in general and it helps reduce climate warming.

_DB:_ Unlike C02, methane that’s captured before it reaches the atmosphere can be sold – and later used as a source of energy.

_JB: Methane capture and resale is already generating energy and revenue at some landfills. Our thanks today to “NASA”:http://www.nasa.gov:_ explore, discover, understand. We’re Block and Byrd for Earth and Sky.

Written by EarthSky