DAILY NEWS BRIEF: A team of earth and atmospheric scientists claimed that the U.S.’s methane emission is about 50 percent higher than previously recorded. The difference is due to an underestimation of the impact of human activities in methane emission.
Cattle farming and fossil fuel production are among the main suspects behind the larger rate of emissions.
Anna Michalak, co-author of the new study and an associate professor in Stanford’s Department of Environmental Earth System Science, explained in to the Stanford Report that the Environmental Protection Agency (EPA) and the international Emissions Database for Global Atmospheric Research (EDGAR) previously recorded emissions from human activities using a “bottom-up approach.” This consisted of calculating totals by measuring methane produced per cow and per unit of fossil fuel.
“It is essentially a book-keeping approach, and the uncertainties of the individual line items can compound when they are added up to estimate total emissions,” Michalak said.
The new study employed a more “top-down” methodology, developed in part by Michalak, which looks to atmospheric methane data that is then traced to a source.
The new method provides complementary data to previous methane emissions records that Michalak hopes can serve as a baseline for future analysis and research.