Rapid rise in the global-warming gas, 86 times more powerful than CO2, is spotted by satellites
By Geoffrey Lean
Startling increases in one of the main pollutants that cause global warming have been unexpectedly discovered over the United States – and the main suspect is the country’s booming fracking industry.
New Harvard University research, drawing on satellite measurements, concludes that US emissions of methane – a much more powerful warming gas than carbon dioxide – have “increased by more than 30 per cent over the past decade”.
The researchers say they “cannot readily attribute” the rise to any particular source but point out that US production of shale gas increased nine times during the same period, while other studies show that many fracking operations are emitting much more methane than has been officially recognised.
If the extraction process proves to be the culprit, it will show that exploiting and burning shale gas has been much more potent in global warming even than using coal, severely undermining energy and climate-change strategies. Both the British and US governments have been banking on shale gas as a relatively clean fuel that would act as a “bridge” to the low carbon economy needed in the next few decades if the world is not to heat up uncontrollably.
Their policy is based on the fact that burning gas emits half as much CO2 as coal. But if large amounts of methane – 86 times more powerful in causing global warming – is emitted via fracking then this advantage will be negated, or overturned.
The findings are an unpleasant surprise, as the US Environmental Protection Agency (EPA) has held there has been no significant rise in emissions of the gas since 2002. But it relies on estimates based on data from emitting industries, while the new study is based on independent satellite measurements.
Oil and gas exploitation, coal mining, livestock and landfills all emit methane, with wetlands the major natural source. The study, published in the journal Geophysical Research Letters, says the rise in emissions is “largest in the central part of the country”. It points out that “the US has seen a 20 per cent increase in oil and gas production, and a ninefold increase in shale gas production” over the relevant period, but adds that the “spatial pattern” of the methane does not “clearly point” to the industry, and calls for more research.