NASA’s EMIT-missie detecteert meer dan 50 methaan „superstralers“ vanuit de ruimte

EMIT Carlsbad New Mexico

Deze afbeelding toont een methaanpluim van 3 kilometer lang die NASA’s Earth Surface Mineral Dust Source Investigation-missie heeft gedetecteerd ten zuidoosten van Carlsbad, New Mexico. Methaan is een krachtig broeikasgas dat veel effectiever is in het vasthouden van warmte in de atmosfeer dan koolstofdioxide. Krediet: NASA/JPL-Caltech

EMIT (Earth Surface Mineral Dust Source Investigation) is gebouwd om wetenschappers te helpen begrijpen hoe stof het klimaat beïnvloedt. Het kan ook de uitstoot van het krachtige broeikasgas lokaliseren.

EMIT was installed on the International Space Station (ISS) in July. In the data it has collected since, the science team has identified more than 50 “super-emitters” in Central Asia, the Middle East, and the Southwestern United States. Super-emitters are facilities, equipment, and other infrastructure that emit methane at exceptionally high rates. They are typically in the fossil fuel, waste, or agriculture sectors.

„Het inperken van de methaanemissies is de sleutel tot het beperken van de opwarming van de aarde. Deze opwindende nieuwe ontwikkeling zal onderzoekers niet alleen helpen om beter vast te stellen waar methaanlekken vandaan komen, maar ook inzicht geven in hoe ze snel kunnen worden aangepakt“, aldus NASA-beheerder Bill Nelson. “Het internationale ruimtestation en de meer dan twee dozijn satellieten en instrumenten van NASA in de ruimte zijn lange tijd van onschatbare waarde geweest bij het bepalen van veranderingen in het klimaat op aarde. EMIT blijkt een cruciaal instrument te zijn in onze gereedschapskist om dit krachtige broeikasgas te meten – en het bij de bron te stoppen.”

Methaan absorbeert infraroodlicht in een uniek patroon – een spectrale vingerafdruk genaamd – dat de beeldspectrometer van EMIT met grote precisie kan onderscheiden en[{“ attribute=““>accuracy. Carbon dioxide can also be measured by the instrument.

The new observations stem from the broad coverage of the planet afforded by the space station’s orbit, as well as from EMIT’s ability to scan swaths of Earth’s surface dozens of miles wide while resolving areas as small as a soccer field.

EMIT East of Hazar Turkmenistan

East of Hazar, Turkmenistan, a port city on the Caspian Sea, 12 plumes of methane stream westward. The plumes were detected by NASA’s Earth Surface Mineral Dust Source Investigation mission and some of them stretch for more than 20 miles (32 kilometers). Credit: NASA/JPL-Caltech

“These results are exceptional, and they demonstrate the value of pairing global-scale perspective with the resolution required to identify methane point sources, down to the facility scale,” said David Thompson. “It’s a unique capability that will raise the bar on efforts to attribute methane sources and mitigate emissions from human activities.” Thompson is EMIT’s instrument scientist and a senior research scientist at NASA’s Jet Propulsion Laboratory (

Relative to carbon dioxide, methane makes up a fraction of human-caused greenhouse-gas emissions, but it’s estimated to be 80 times more effective, ton for ton, at trapping heat in the atmosphere in the 20 years after release. Moreover, where carbon dioxide lingers for centuries, methane persists for about a decade, meaning that if emissions are reduced, the atmosphere will respond in a similar timeframe, leading to slower near-term warming.

EMIT Tehran Iran

A methane plume at least 3 miles (4.8 kilometers) long billows into the atmosphere south of Tehran, Iran. The plume, detected by NASA’s Earth Surface Mineral Dust Source Investigation mission, comes from a major landfill, where methane is a byproduct of decomposition. Credit: NASA/JPL-Caltech

Identifying methane point sources can be a key step in the process. With knowledge of the locations of big emitters, operators of facilities, equipment, and infrastructure giving off the gas can quickly act to limit emissions.

EMIT’s methane observations came as scientists verified the accuracy of the imaging spectrometer’s mineral data. Over its mission, EMIT will collect measurements of surface minerals in arid regions of Africa, Asia, North and South America, and Australia. The data will help researchers better understand airborne dust particles’ role in heating and cooling Earth’s atmosphere and surface.

“We have been eager to see how EMIT’s mineral data will improve climate modeling,” said Kate Calvin, NASA’s chief scientist and senior climate advisor. “This additional methane-detecting capability offers a remarkable opportunity to measure and monitor greenhouse gases that contribute to climate change.”

Detecting Methane Plumes

The mission’s study area coincides with known methane hotspots around the world, enabling researchers to look for the gas in those regions to test the capability of the imaging spectrometer.

“Some of the plumes EMIT detected are among the largest ever seen – unlike anything that has ever been observed from space,” said Andrew Thorpe, a research technologist at JPL leading the EMIT methane effort. “What we’ve found in a just a short time already exceeds our expectations.”

EMIT Methane Turkmenistan

The cube (left) shows methane plumes (purple, orange, yellow) over Turkmenistan. The rainbow colors are the spectral fingerprints from corresponding spots in the front image. The blue line in the graph (right) shows the methane fingerprint EMIT detected; the red line is the expected fingerprint based on an atmospheric simulation. Credit: NASA/JPL-Caltech

For example, the instrument detected a plume about 2 miles (3.3 kilometers) long southeast of Carlsbad, New Mexico, in the Permian Basin. One of the largest oilfields in the world, the Permian spans parts of southeastern New Mexico and western Texas.

In Turkmenistan, EMIT identified 12 plumes from oil and gas infrastructure east of the Caspian Sea port city of Hazar. Blowing to the west, some plumes stretch more than 20 miles (32 kilometers).

The team also identified a methane plume south of Tehran, Iran, at least 3 miles (4.8 kilometers) long, from a major waste-processing complex. Methane is a byproduct of decomposition, and landfills can be a major source.

Scientists estimate flow rates of about 40,300 pounds (18,300 kilograms) per hour at the Permian site, 111,000 pounds (50,400 kilograms) per hour in total for the Turkmenistan sources, and 18,700 pounds (8,500 kilograms) per hour at the Iran site.

Who are the biggest methane emitters?

China, the United States, Russia, India, Brazil, Indonesia, Nigeria, and Mexico are estimated to be responsible for nearly half of all anthropogenic methane emissions. The major methane emission sources for these countries vary greatly. For example, a key source of methane emissions in China is coal production, whereas Russia emits most of its methane from natural gas and oil systems. The largest sources of methane emissions from human activities in the United States are oil and gas systems, livestock enteric fermentation, and landfills.

The Turkmenistan sources together have a similar flow rate to the 2015 Aliso Canyon gas leak, which exceeded 110,000 pounds (50,000 kilograms) per hour at times. The Los Angeles-area disaster was among the largest methane releases in U.S. history.

With wide, repeated coverage from its vantage point on the space station, EMIT will potentially find hundreds of super-emitters – some of them previously spotted through air-, space-, or ground-based measurement, and others that were unknown.

“As it continues to survey the planet, EMIT will observe places in which no one thought to look for greenhouse-gas emitters before, and it will find plumes that no one expects,” said Robert Green, EMIT’s principal investigator at JPL.

EMIT is the first of a new class of spaceborne imaging spectrometers to study Earth. One example is Carbon Plume Mapper (CPM), an instrument in development at JPL that’s designed to detect methane and carbon dioxide. JPL is working with a nonprofit, Carbon Mapper, along with other partners, to launch two satellites equipped with CPM in late 2023.

More About the Mission

EMIT was selected from the Earth Venture Instrument-4 solicitation under the Earth Science Division of NASA Science Mission Directorate and was developed at NASA’s Jet Propulsion Laboratory (JPL), which is managed for the agency by the California Institute of Technology (Caltech) in Pasadena, California. It launched aboard a

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