NASA scientists are helping California create a detailed, nationwide inventory of methane source sources ̵
Like carbon dioxide, methane stores heat in the atmosphere, but more efficiently and for a shorter period of time. Scientists estimate that most of the methane emissions in California are caused by industrial plants such as oil and gas fields, large dairies and landfills. To reduce the impact of methane on the climate, the state has made reducing human-induced emissions a priority. However, to reduce these hard-to-detect emissions, they must be measured and sources identified.
NASA, in partnership with the California Air Resources Board (CARB) and the California Energy Commission, has decided to do just that. Over a two-year period, a research team from NASA's Jet Propulsion Laboratory in Pasadena, California, deployed a plane equipped with the next generation Airborne Visible InfraRed Imaging Spectrometer (AVIRIS-NG) with over 300,000 facilities and infrastructure components these sectors. The instrument can detect methane clouds in great detail. Each pixel covers an area of about 3 meters (10 feet), so scientists can spot small, often undiscovered flags.
The team identified more than 550 individual point sources emitting high-concentration methane flags. Ten percent of these sources, considered super-emitters, contributed most of the observed emissions. The team estimates that nationwide super-emitters account for about one-third of California's total methane budget.
Such emissions data can help plant operators identify and fix problems – and help bring California closer to its emissions targets. For example, it was observed that out of the 270 landfills surveyed, only 30 emitted large amounts of methane. However, these 30 accounted for 40% of the total emissions from point sources identified in the survey. This type of data could help these facilities identify potential leaks or disruptions in their gas separation systems.
"These results illustrate the importance of monitoring point sources across multiple sectors [of the economy] and across broader regions, both for a better understanding of methane." Riley Duren, lead researcher, led the work for the Jet Propulsion Laboratory of the NASA.
Initial results have been shared with plant operators in California to raise awareness of the need to improve their methane leak detection processes and introduce better control of methane emissions. The results will also be used to help government and local authorities and companies prioritize investment in methane emissions reduction.
Although the survey provides a detailed map of methane emissions for the areas observed in the state, researchers warn that this was the first attempt to estimate the emissions of individual methane sources from a large population spread over such a large area over several years.
In addition, this study should include highly concentrated releases of methane from a single component or an industrial device, such as oil well. The survey excluded non-point sources such as small gas leaks from millions of households, as their individual emissions are below the levels of detection of this method, although they may have a collective impact on atmospheric methane levels.
builds on a decade of collaboration between NASA, CARB, and the California Energy Commission to support the state's ambitious climate protection program, particularly with a view to investigating the effects of air pollution from the oil and gas sector.
"This new remote sensing technology addresses the continuing need for detailed and high-quality data on methane," said Mary D. Nichols, chair of the California Air Resources Board. "It will help us and the Energy Commission to develop the best strategies for the capture of this highly efficient greenhouse gas."
The Californian Methane Final Report will be available in the fall.
The map and data of this survey can be viewed here: methane.jpl.nasa.gov/
Natural gas leaks are an important source of greenhouse gas emissions in Los Angeles
Riley M. Duren et al. California's Methane Super Emitter, Nature (2019). DOI: 10.1038 / s41586-019-1720-3
One-third of Californian methane is due to some super-emitters (2019, 7 November)
retrieved on November 7, 2019
This document is subject to copyright. Apart from any fair dealings for the purpose of private learning or research, no
Part may be reproduced without written permission. The content is for informational purposes only.