Source: Sid Perkins, Science Mag, July 19
Natural gas, long touted as a cleaner burning alternative to coal, has a leakage problem. A new study has found that leaks of methane, the main ingredient in natural gas and itself a potent greenhouse gas, are twice as big as official tallies suggest in major cities along the U.S. eastern seaboard. The study suggests many of these fugitive leaks come from homes and businesses—and could represent a far bigger problem than leaks from the industrial extraction of the fossil fuel itself.
“This is an issue that people tend to ignore when trying to estimate methane emissions,” says Kathryn McKain, an atmospheric scientist with the National Oceanic and Atmospheric Administration’s Earth System Research Laboratory in Boulder, Colorado, who wasn’t involved in the new research. When compared with the global amount of natural and human-driven methane emissions, she notes, “These emissions are small, but they’re preventable.”
When burned for heat or power, methane emits less carbon dioxide (CO2) than fossil fuels such as coal. But when leaked directly into the atmosphere, its warming effect can be dozens of times stronger than CO2, depending on the time scale over which the warming is measured.