This image shows a methane plume 2 miles (3 kilometers) long that NASA’s Earth Surface Mineral Dust Source Investigation mission detected southeast of Carlsbad, New Mexico. Methane is a potent greenhouse gas that is much more effective at trapping heat in the atmosphere than carbon dioxide. Credits: NASA/JPL-Caltech
Built to help scientists understand how dust affects climate, the Earth
Surface Mineral Dust Source Investigation can also pinpoint emissions of the
potent greenhouse gas.
NASA’s Earth Surface Mineral Dust Source Investigation (EMIT) mission is mapping the prevalence of key
minerals in the planet’s dust-producing deserts – information that will advance
our understanding of airborne dust’s effects on climate. But EMIT has
demonstrated another crucial capability: detecting the presence of methane, a
potent greenhouse gas.
In the data EMIT
has collected since being installed on the International Space Station in July,
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, typically in the fossil-fuel,
waste, or agriculture sectors, that emit methane at high rates.
“Reining in methane emissions is key to
limiting global warming. This exciting new development will not only help
researchers better pinpoint where methane leaks are coming from, but also
provide insight on how they can be addressed – quickly,” said NASA
Administrator Bill Nelson. “The International Space Station and NASA’s more
than two dozen satellites and instruments in space have long been invaluable in
determining changes to the Earth’s climate. EMIT is proving to be a critical
tool in our toolbox to measure this potent greenhouse gas – and stop it at the
source.”
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). Credits: NASA/JPL-Caltech
Methane absorbs infrared light in a unique pattern – called a spectral
fingerprint – that EMIT’s imaging spectrometer can discern with high accuracy
and precision. The instrument can also measure carbon dioxide.
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.
“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, EMIT’s instrument
scientist and a senior research scientist at NASA’s Jet Propulsion Laboratory in
Southern California, which manages the mission. “It’s a unique capability that
will raise the bar on efforts to attribute methane sources and mitigate
emissions from human activities.”
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.
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. Credits: 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.
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. Credits: NASA/JPL-Caltech
“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.”
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.
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,
which is managed for the agency by Caltech in Pasadena, California. It launched
aboard a SpaceX Dragon resupply spacecraft from NASA’s Kennedy Space Center in
Florida on July 14, 2022. The instrument’s data will be delivered to the NASA
Land Processes Distributed Active Archive Center (DAAC) for use by other
researchers and the public.
The International Space Station hosts seven instruments for NASA Earth Science that are providing novel information for understanding our changing planet.
To learn more about the mission, visit: https://earth.jpl.nasa.gov/emit/
Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
Source: Methane
‘Super-Emitters’ Mapped by NASA’s New Earth Space Mission | NASA
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