Natural gas, also known as methane, is one of several “greenhouse gases” that trap heat radiation trying to leave the Earth. Molecule-for-molecule, methane warms our planet’s atmosphere about 25X more than carbon dioxide.
Methane concentrations are increasing in our atmosphere, likely due to human activities. Culprits range from leakage from the oil and gas industry to emissions from rice paddies and cow burps. Rice cultivation and diets rich in meats have increased markedly during the past 100 years, along with our consumption of petroleum.
Industries responsible for methane leakage are quick to point the finger to other potential sources. Several recent studies have reported methane emissions from trees. Hollow trees harbor anaerobic bacteria inside, which release methane. Other trees, living in flooded soils, conduct methane upward inside their trunks, emitting methane from the surface of their leaves and bark.
Emissions of methane from trees are part of Earth’s total methane budget, which includes natural and human-derived sources. We should not let this minor source of methane divert our attention from emissions from our own activities, which have tripled methane concentrations in our atmosphere over the past century.
Plugging methane leaks from gas wells and pipelines is the most effective and straightforward way to curtail the rise of methane in our atmosphere and mitigate the potential for undesirable climate change. The companies that supply natural gas to our homes will benefit by reducing the waste of a product they want to sell.
Pinning the blame on trees is little more than a distraction.
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–This segment was adapted from a blog post by William Schlesinger, biogeochemist and Emeritus President of the Cary Institute of Ecosystem Studies.
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Photo, posted March 13, 2010, courtesy of Schristia via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio, with script contribution from the Cary Institute of Ecosystem Studies.