U.S. oil and gas production has tripled in the last 15 years, but new CIRES and NOAA research finds ethane emissions decreased relative to oil and gas production from 2014 to 2020. The results indicate oil and gas operators have gotten better at reducing emissions of greenhouse gases and other pollutants — but scientists still need to track these emissions over time. 

Ethane is one of many gases emitted during oil production. Ethane is not a greenhouse gas itself, but is used as a tracer to detect emissions of methane, the second-most important greenhouse gas after carbon dioxide. 

Scientists have struggled to measure oil and gas emissions consistently over time, but CIRES researcher Colby Francoeur and his colleagues developed a new method of observing ethane from space. In a new study published in Geophysical Research Letters, the researchers describe how they tracked ethane using the Cross-track Infrared Sounder on a NOAA polar-orbiting weather satellite. 

In the new study, Francoeur and his colleagues used the satellite data to measure daily ethane emissions from 2014 to 2020 over the Permian Basin, the largest oil and gas field in the United States. Located in southern New Mexico and western Texas, the Permian Basin accounts for about a quarter of U.S. oil and gas production annually. 

The researchers found ethane increased by 5.6 percent every year, but because oil and gas production in the basin increased by about 30 percent each year during the same period, the proportion of ethane entering the atmosphere has been getting significantly smaller. The findings are consistent with improved operating practices and leak repairs, according to the study authors. Getting an accurate estimate of how much is leaking into the atmosphere helps scientists understand how much oil and gas activities are contributing to climate change.