NASA Instrument on ISS Pinpoints Over 750 Greenhouse Gas Sources, Unveiling a Climate Reality Check

The more we learn about our climate, the better prepared we will be to confront the things that are hurting it. So, in July 2022, NASA launched the Earth Surface Mineral Dust Source Investigation (EMIT) instrument to investigate 10 critical minerals in some of the world’s most dry regions, as well as how lofted dust in those locations influences our climate.

However, a recent study has utilized data from the device to detect over 750 point-source emissions of greenhouse gases, including methane sources from landfills, agricultural locations, and oil and gas installations.

Carbon dioxide and methane emissions are the two main anthropogenic climate-forcing agents, and they constitute a significant source of uncertainty in the global carbon budget. Uncertainties are exacerbated when emissions occur at tiny spatial scales, making attribution difficult. We report the first results from NASA’s Earth Surface Mineral Dust Source Investigation (EMIT) imaging spectrometer, demonstrating the measurement and attribution of fine-scale methane and carbon dioxide sources from the oil and gas, waste, and energy industries. Methane emissions varied on a regional scale for selected nations monitored during the first 30 days of EMIT operations, with Turkmenistan having the highest overall emissions. These findings emphasize the roles of existing and proposed point source imagers in closing global carbon budgets.

While detecting greenhouse gases such as methane was not part of EMIT’s core function, the image spectrometer aboard the International Space Station (ISS) has demonstrated such capability. “We were a little cautious at first about what we could do with the instrument,” said Andrew Thorpe, the paper’s main author, in a statement.

“It has exceeded our expectations,” he said.

EMIT was able to detect both major sources (emitting tens of thousands of pounds of methane per hour) and tiny sources (releasing hundreds of pounds of methane per hour) among the 750 methane sources. This is significant because it gives reliable data on “super-emitters,” or methane sources that account for a disproportionate fraction of emissions.

Methane is a very potent—and harmful—greenhouse gas. It traps heat up to 80 times more effectively than carbon dioxide. As these emissions are typically caused by humans, being able to identify their origins can eventually help scientists devise measures to control harmful emissions. They are also directly accountable for the global warming catastrophe.

Methane-detecting sensors are typically launched from airplanes. These devices are more sensitive at detecting methane sources at a lower altitude (around a few thousand feet) than EMIT, but such aircraft can only cover a restricted region for a limited period. These missions are frequently deemed too remote, dangerous, or expensive, and occasionally a mix of the three.

However, from 250 miles (402 kilometers) above our globe on the ISS, EMIT managed to observe 60% to 80% of the methane plumes generally recorded in similar aerial experiments in its first 30 days of observation. EMIT’s imaging spectrometer captures pictures of the planet’s surface, measuring 50 miles by 50 miles (80 kilometers by 80 kilometers). These are referred to by researchers as “scenes.”

Many pictures contain areas that are much outside the range of most methane detection planes.

While NASA missions frequently focus on gazing outward into space, EMIT demonstrates that it is equally necessary to gaze within.

NASA’s Green Guardian: Mission Excelling in Identifying Greenhouse Gas Emission Sources

Since its arrival on the International Space Station 16 months ago, the EMIT imaging spectrometer has demonstrated the ability to identify more than simply surface minerals.

Data from NASA’s EMIT instrument, which first detected methane plumes from its perch atop the International Space Station more than a year ago, is now being used to pinpoint point-source emissions of greenhouse gases with a precision that has shocked even its inventors.

EMIT, which stands for Earth Surface Mineral Dust Source Investigation, was begun in July 2022 with the goal of mapping 10 important minerals on the surface of the world’s dry areas. Those mineral-related measurements, which are now available to academics and the general public, will contribute to a better understanding of how dust in the atmosphere influences climate.

EMIT has proven to be successful in detecting both large (tens of thousands of pounds of methane per hour) and small (hundreds of pounds of methane per hour) emission sources. This is significant because it allows for the identification of a higher number of “super-emitters”—sources  that contribute disproportionately to overall emissions.

According to the latest study, EMIT can identify 60% to 85% of the methane plumes normally found in aerial operations in its first 30 days of operation.

Methane-detecting devices aboard planes are more sensitive from several thousand feet above the ground, but to justify deploying a plane, researchers require previous evidence that they would detect methane. Many locations are not investigated because they are deemed too remote, dangerous, or expensive. Furthermore, the campaigns that do exist cover very small areas for short periods of time.

EMIT, on the other hand, collects data across a vast swath of the earth from roughly 250 miles (400 kilometers) above the space station, notably the dry regions that lie between 51.6 degrees north and south latitude. The imaging spectrometer records 50-mile-by-50-mile (80-kilometer-by-80-kilometer) photographs of the surface, dubbed “scenes” by researchers, and includes many locations previously out of reach of airborne instrumentation.

“The number and scale of methane plumes measured by EMIT around our planet is stunning,” said Robert O. Green, senior research scientist at JPL and EMIT’s main investigator.