However, the sheer number of abandoned wells, combined with poor documentation and record-keeping, made it difficult to even know how many wells existed, much less develop reasonable strategies for mitigation.Kang, Jackson, and colleagues combined new field measurements from 88 wells in Pennsylvania with information gathered from old books, published literature, historical state documents, and modern databases to paint a more accurate picture of both the number of abandoned wells and the traits of highest emitters.Instead, the real culprits behind the spike – previously blamed on fracking of natural gas in the US and elsewhere – are wetlands and rice paddies in the tropics.Methane is the second-most important greenhouse gas responsible for global warming, after carbon dioxide.
“In a way that’s good news—if we can identify the super emitters quickly and cheaply, we can address most of the problems,” Jackson says.
The finding that the fossil fuel industry’s claims about the size of its methane emissions are serious underestimates mean that many national emissions inventories submitted to UN climate negotiators may be wrong.
The team’s estimate that fossil fuel emissions are twice as big as thought included figures from natural geological seepage of gas.
With those excluded, the estimates for the fossil fuel industry alone are still between 20 and 60 per cent greater than inventories suggest.
“The natural gas industry is becoming much better at controlling gas leaks,” says Nisbet.
, are from the largest study of high methane-emitting abandoned oil and gas wells in the state, which has oil and gas infrastructure dating back to 1859.