Launched in 2017 aboard the Copernicus Sentinel-5 Precursor satellite, the TROPOMI (TROPOspheric Monitoring Instrument Monitoring Instrument) is the first instrument in space that can reliably track methane emissions into the atmosphere. In particular, in 2019 and 2020, the researchers found about 1800 cases of the release of this gas.
Methane is the second largest contributor to climate change after carbon dioxide, but until recently it has received far less attention when it comes to climate action. Although methane lingers in the atmosphere for much less time than CO 2 , in the short term it is a much more powerful warming gas and has a huge impact on global warming.
“One of the problems with methane is that it’s not always easy to know where it comes from. The vast majority of human methane emissions on the planet today remain “invisible” because they are not monitored — at least not comprehensively and irregularly,” said Riley Duren, Carbon Mapper executive director and researcher at the University of Arizona.
An analysis in February by the International Energy Agency found that methane emissions from oil, gas and coal are about 70% higher than officially reported by governments. According to Lena Höglund-Isaksson, a methane researcher at the International Institute for Applied Systems Analysis, if the world is ever going to achieve significant reductions in the gas, it needs to know where it’s coming from. And it is TROPOMI and other new generation satellites that can help in this.
“Several new satellites with much higher resolution are planned to be launched over the next few years, including MethaneSat, which is scheduled to launch by the non-profit US Environmental Defense Fund (EDF) in early 2023, and two satellites from Carbon Mapper in late 2023. In general, Carbon Mapper plans to launch an entire “constellation” of satellites into orbit by 2025, ”said the scientist.
These satellites will enable unprecedented precision in tracking the sources of the potent greenhouse gas, she said, and are expected to eventually help stop emissions.
“In particular, MethaneSat will be able to detect leaks of up to 5 kg per hour per square kilometer, which is much less than the 25 tons per hour that Tropomi can detect. It will provide information on how much emissions come from a particular area, which can then be aggregated by country. MethaneSat will be especially useful for better understanding methane coming from parts of the world where it is more difficult to fly an aircraft with a sensor, such as Russia,” said EDF climatologist Ilissa Okko.
The Carbon Mapper satellites, in turn, will be able to focus on individual methane sources with a spatial resolution of just 30 meters.
“Their ultimate goal is to provide daily or weekly monitoring of all high emission regions around the planet and make these methane and CO 2 data publicly available,” Düren said.
Once all 20 satellites are in orbit in the mid-2020s, Carbon Mapper hopes to increase satellite detection to around 90% of leaks in the oil and gas sector.
While the largest man-made source of methane is agriculture (specifically cow raising and rice farming), scientists believe that the greatest potential for reducing methane emissions easily in the short term is the fossil fuel industry. The researchers said that by 2030 it is possible to cut 50% of methane emissions from the oil and gas sector at no net cost.