Researchers at the Lamont-Doherty Earth Observatory, part of the Columbia Climate School, published the findings today in Atmospheric Chemistry and Physics. Their conclusion is that natural gas use is the main driver of methane emissions in the New York City metropolitan area.

Methane is a potent greenhouse gas, and the study frames unused natural gas as an overlooked target for cities trying to cut emissions. The same waste, the authors note, carries a cost to consumers.

What the study does not settle, on the evidence here, is how much of the total comes from each specific source or how quickly any fix would pay off. The figures behind the $300 million framing are not detailed in the material available to us.