Is Food Production Our Best Hope For Reducing Methane Emissions?

Wednesday, December 13th, 2017 | 842 Views

A major opportunity for avoiding climate change’s worst impacts lies in reducing methane emissions, particularly from food production, according to two studies published in the journals Earth System Science Data and Environmental Research Letters.

Emissions of methane have increased significantly in recent years and are approaching an internationally recognised worst-case scenario for greenhouse gas emissions, according to the studies. If left unchecked, this increase could see temperatures rise as much as 4 deg C, accelerating rise of the sea level, and more extreme weather.

The alarming increase in methane raises an increasing need to manage the emissions for climate change mitigation.

While most mitigation efforts have focussed on carbon dioxide, methane warming potential is about 28 times greater in a hundred-year time span, and its lifespan in the atmosphere is much shorter. In other words, it can do major damage, but getting it under control could change the climate change equation relatively swiftly.

“Methane presents the best opportunity to slow climate change quickly,” said Rob Jackson, co-author of the studies, chair of US-based Stanford University’s Earth System Science Department and head of the Global Carbon Project. “Carbon dioxide has a longer reach, but methane strikes faster.”

The research findings revealed that methane concentrations were stagnant for years up until a decade ago. And unlike carbon dioxide, the bulk of methane emissions are human-driven. Chief among those, according to the analysis, are agricultural sources such as livestock, which emit methane through bodily functions and manure, and rice fields, which emit methane when flooded. Humans are responsible for 60 percent of all methane emissions globally.

To resolve discrepancies on the magnitude of emissions and regional trends, the team of researchers recommend more accurate partitioning of methane emissions and sinks by region and process, and more interactions among scientific groups developing emissions inventories.

A few potential solutions for agriculture include breeding rice to require less flooding, altering feed for livestock to lessen intestinal processes that create methane, promoting less meat-intensive diets and deploying more farm bio-digesters.

Other opportunities to cut methane emissions include venting and flaring of methane in coal mines, detecting and removing natural gas leaks from oil and gas drilling operations and covering landfills to capture methane emissions.