A recent McGill study published in Environmental Science and Technology finds that annual methane emissions from abandoned oil and gas (AOG) wells in Canada and the US have been greatly underestimated—by as much as 150% in Canada, and by 20% in the US. Indeed, the research suggests that methane gas emissions from AOG wells are currently the 10th and 11th largest sources of anthropogenic methane emission in the US and Canada, respectively. Since methane gas is a more important contributor to global warming than carbon dioxide, especially over the short term, the researchers believe that it is essential to gain a clearer understanding of methane emissions from AOG wells to understand their broader environmental impacts and move towards mitigating the problem.