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Earth (ESD) Earth Explore Explore Earth Science Climate Change Air Quality Science in Action Multimedia Image Collections Videos Data For Researchers About Us 8 Min Read NASA Researchers Study Coastal Wetlands, Champions of Carbon Capture
Florida’s coastal wetlands are a complex patchwork of ecosystem — consisting of sawgrass marshland, hardwood hammocks, freshwater swamps, and mangrove forests. Credits:
NASA/ Nathan Marder Across the street from the Flamingo Visitor’s Center at the foot of Florida’s Everglades National Park, there was once a thriving mangrove population — part of the largest stand of mangroves in the Western Hemisphere. Now, the skeletal remains of the trees form one of the Everglades’ largest ghost forests.
When Hurricane Irma made landfall in September 2017 as a category 4 storm, violent winds battered the shore and a storm surge swept across the coast, decimating large swaths of mangrove forest. Seven years later, most of the mangroves here haven’t seen any new growth. “At this point, I doubt they’ll recover,” said David Lagomasino, a professor of coastal studies at East Carolina University.
Lagomasino was in the Everglades conducting fieldwork as part of NASA’s BlueFlux Campaign, a three-year project that aims to study how sub-tropical wetlands influence atmospheric levels of carbon dioxide (CO2) and methane. Both gases absorb solar radiation and have a warming effect on Earth’s atmosphere.
A mangrove “ghost forest” near Florida’s southernmost coast houses the remains of a once-thriving mangrove stand. NASA/Nathan Marder The campaign is led by Ben Poulter, a researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who studies the way human activity and climate change affect the carbon cycle. As wetland vegetation responds to increasing temperatures, rising sea levels, and severe weather, Poulter’s team is trying to determine how much carbon dioxide wetland vegetation removes from the atmosphere and how much methane it produces. Ultimately this research will help scientists develop models to estimate and monitor greenhouse gas concentrations in coastal areas around the globe.
Although coastal wetlands account for less than 2% of the planet’s land-surface area, they remove a significant amount of carbon dioxide from the atmosphere. Florida’s coastal wetlands alone remove an estimated 31.8 million metric tons each year. A commercial aircraft would have to circle the globe more than 26,000 times to produce the same amount of carbon dioxide. Coastal wetlands also store carbon in marine sediments, keeping it underground — and out of the atmosphere — for thousands of years. This carbon storage capacity of oceans and wetlands is so robust that it has its own name: blue carbon.
“We’re worried about losing that stored carbon,” Poulter said. “But blue carbon also offers tremendous opportunities for climate mitigation if conservation and restoration are properly supported by science.”
The one-meter core samples collected by Lagomasino will be used to identify historic rates of blue carbon development in mangrove forests and to evaluate how rates of carbon storage respond to specific environmental pressures, like sea level rise or the increasing frequency of tropical cyclones.
Early findings from space-based flux data confirm that, in addition to acting as a sink of carbon dioxide, tropical wetlands are a significant source of methane — a greenhouse gas that traps heat roughly 80 times more efficiently than carbon dioxide. In fact, researchers estimate that Florida’s entire wetland expanse produces enough methane to offset the benefits of wetland carbon removal by about 5%.
Everglades peat contains history of captured carbon
During his most recent fieldwork deployment, Lagomasino used a small skiff to taxi from one research site to the next; many parts of the Everglades are virtually unreachable on foot. At each site, he opened a broad, black case and removed a metallic peat auger, which resembles a giant letter opener. The instrument is designed to extract core samples from soft soils. Everglades peat — which is composed almost entirely of the carbon-rich, partially decomposed roots, stems, and leaves of mangroves — offers a perfect study subject.
Lagomasino plunged the auger into the soil, using his body weight to push the instrument into the ground. Once the sample was secured, he freed the tool from the Earth, presenting a half-cylinder of soil. Each sample was sealed and shipped back to the lab — where they are sliced horizontally into flat discs and analyzed for their age and carbon content.
East Carolina University professor of coastal studies David Lagomasino (right) and his doctoral student Daystar Babanawo explore the Everglades by boat. The plant life here consists almost entirely of mangroves, which can withstand the saltwater tides that characterize coastal wetlands. Scientific studies of Florida’s coastal ecosystems have historically been limited by the relative inaccessibility of the region. NASA/Nathan Marder Everglades peat forms quickly. In Florida’s mangrove forests, around 2 to 10 millimeters of soil are added to the forest floor each year, building up over time like sand filling an hourglass. Much like an ice core, sediment cores offer a window into Earth’s past. The deeper the core, the further into the past one can see. By looking closely at the contents of the soil, researchers can uncover information about the climate conditions from the time the soil formed.
In some parts of the Everglades, soil deposits can reach depths of up to 3 meters (10 feet), where one meter might represent close to 100 years of peat accumulation, Lagomasino said. Deep in the Amazon rainforest, by comparison, a similarly sized, one-meter deposit could take more than 1,000 years to develop. This is important in the context of restoration efforts: in coastal wetlands, peat losses can be restored up to 10 times faster than they might be in other forest types.
Lagomasino holds a sample of peat soil collected from the forest floor. The source of the soil’s elevated carbon content — evident from its coarse, fibrous texture — is primarily the thread-like root hairs routinely recycled by the surrounding mangroves. The presence of water slows the decomposition of this organic material, which is why wetlands can lock carbon away and prevent it from escaping into the atmosphere for thousands of years. NASA/Nathan Marder “There are also significant differences in fluxes between healthy mangroves and degraded ones,” said Lola Fatoyinbo, a research scientist in the Biospheric Sciences Laboratory at NASA’s Goddard Space Flight Center. In areas where mangrove forests are suffering, for example, after a major hurricane, “you end up with more greenhouse gases in the atmosphere,” she said. As wetland ecology responds to intensifying natural and human pressures, the data product will help researchers precisely monitor the impact of ecological changes on global carbon dioxide and methane levels.
Wetland methane: A naturally occurring but potent greenhouse gas
Methane is naturally produced by microbes that live in wetland soils. But as wetland conditions change, the growth rate of methane-producing microbes can spike, releasing the gas into the atmosphere at prodigious rates.
Since methane is a significantly more potent greenhouse gas than carbon dioxide, possessing a warming potential 84 times greater over a 25-year period, methane emissions undermine some of the beneficial services that blue carbon ecosystems provide as natural sinks for atmospheric carbon dioxide.
While Lagomasino studied the soil to understand long-term storage of greenhouse gases, Lola Fatoyinbo, a research scientist in NASA’s Biospheric Sciences Lab, and Peter Raymond, an ecologist at Yale University’s School of the Environment, measured the rate at which these gases are exchanged between wetland vegetation and the atmosphere. This metric is known as gaseous flux.
Lagomasino holds a sample of peat soil collected from the forest floor. The presence of water slows the decomposition of this organic material, which is why wetlands can lock carbon away and prevent it from escaping into the atmosphere for thousands of years. NASA/Nathan Marder NASA/Nathan Marder The scientists measure flux using chambers designed to adhere neatly to points where significant rates of gas exchange occur. They secure box-like chambers to above-ground roots and branches while domed chambers measure gas escaping from the forest floor. The concentration of gases trapped in each chamber is measured over time.
In general, as the health of wetland ecology declines, less carbon dioxide is removed, and more methane is released. But the exact nature of the relationship between wetland health and gaseous flux is not well understood. What does flux look like in ghost forests, for example? And how do more subtle changes in variables like canopy coverage or species distribution influence levels of carbon dioxide sequestration or methane production?
“We’re especially interested in the methane part,” Fatoyinbo said. “It’s the least understood, and there’s a lot more of it than we previously thought.”
Based on data collected during BlueFlux fieldwork, “we’re finding that coastal wetlands remove massive amounts of carbon dioxide and produce substantial amounts of methane,” Poulter said. “But overall, these ecosystems appear to provide a net climate benefit, removing more greenhouse gases than they produce.” That could change as Florida’s wetlands respond to continued climate disturbances.
The future of South Florida’s ecology
Florida’s wetlands are roughly 5,000 years old. But in just the past century, more than half of the state’s original wetland coverage has been lost as vegetation was cleared and water was drained to accommodate the growing population. The Everglades system now contains 65% less peat and 77% less stored carbon than it did prior to drainage. The future of the ecosystem — which is not only an important reservoir for atmospheric carbon, but a source of drinking water for more than 7 million Floridians and a home to flora and fauna found nowhere else on Earth — is uncertain.
Scientists who have dedicated their careers to understanding and restoring South Florida’s ecology are hopeful. “Nature and people can coexist,” said Meenakshi Chabba, an ecologist and resilience scientist at the Everglades Foundation in Florida’s Miami-Dade County. “But we need good science and good management to reach that goal.”
The next step for NASA’s BlueFlux campaign is the development of a satellite-based data product that can help regional stakeholders evaluate in real-time how Florida’s wetlands are responding to restoration efforts designed to protect one of the state’s most precious natural resources — and all those who depend on it.
By Nathan Marder
NASA’s Goddard Space Flight Center, Greenbelt, Maryland
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Last Updated Mar 13, 2025 Editor Jenny Marder Contact Nathan Marder Related Terms
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
Communities in coastal areas such as Florida, shown in this 1992 NASA image, are vulnerable to the effects of sea level rise, including high-tide flooding. A new agency-led analysis found a higher-than-expected rate of sea level rise in 2024, which was also the hottest year on record.NASA Last year’s increase was due to an unusual amount of ocean warming, combined with meltwater from land-based ice such as glaciers.
Global sea level rose faster than expected in 2024, mostly because of ocean water expanding as it warms, or thermal expansion. According to a NASA-led analysis, last year’s rate of rise was 0.23 inches (0.59 centimeters) per year, compared to the expected rate of 0.17 inches (0.43 centimeters) per year.
“The rise we saw in 2024 was higher than we expected,” said Josh Willis, a sea level researcher at NASA’s Jet Propulsion Laboratory in Southern California. “Every year is a little bit different, but what’s clear is that the ocean continues to rise, and the rate of rise is getting faster and faster.”
This graph shows global mean sea level (in blue) since 1993 as measured by a series of five satellites. The solid red line indicates the trajectory of this increase, which has more than doubled over the past three decades. The dotted red line projects future sea level rise.NASA/JPL-Caltech In recent years, about two-thirds of sea level rise was from the addition of water from land into the ocean by melting ice sheets and glaciers. About a third came from thermal expansion of seawater. But in 2024, those contributions flipped, with two-thirds of sea level rise coming from thermal expansion.
“With 2024 as the warmest year on record, Earth’s expanding oceans are following suit, reaching their highest levels in three decades,” said Nadya Vinogradova Shiffer, head of physical oceanography programs and the Integrated Earth System Observatory at NASA Headquarters in Washington.
Since the satellite record of ocean height began in 1993, the rate of annual sea level rise has more than doubled. In total, global sea level has gone up by 4 inches (10 centimeters) since 1993.
This long-term record is made possible by an uninterrupted series of ocean-observing satellites starting with TOPEX/Poseidon in 1992. The current ocean-observing satellite in that series, Sentinel-6 Michael Freilich, launched in 2020 and is one of an identical pair of spacecraft that will carry this sea level dataset into its fourth decade. Its twin, the upcoming Sentinel-6B satellite, will continue to measure sea surface height down to a few centimeters for about 90% of the world’s oceans.
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This animation shows the rise in global mean sea level from 1993 to 2024 based on da-ta from five international satellites. The expansion of water as it warms was responsible for the majority of the higher-than-expected rate of rise in 2024.NASA’s Scientific Visualization Studio Mixing It Up
There are several ways in which heat makes its way into the ocean, resulting in the thermal expansion of water. Normally, seawater arranges itself into layers determined by water temperature and density. Warmer water floats on top of and is lighter than cooler water, which is denser. In most places, heat from the surface moves very slowly through these layers down into the deep ocean.
But extremely windy areas of the ocean can agitate the layers enough to result in vertical mixing. Very large currents, like those found in the Southern Ocean, can tilt ocean layers, allowing surface waters to more easily slip down deep.
The massive movement of water during El Niño — in which a large pool of warm water normally located in the western Pacific Ocean sloshes over to the central and eastern Pacific — can also result in vertical movement of heat within the ocean.
Learn more about sea level:
https://sealevel.nasa.gov
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By NASA
The NISAR mission will help map crops and track their development through the entire growing season. Using synthetic aperture radar, the satellite will be able to observe both small plots of farmland and monitor trends across broad regions, gathering data to in-form agricultural decision making.Adobe Stock/Greg Kelton Data from the NISAR satellite will be used to map crop growth, track plant health, and monitor soil moisture — offering detailed, timely information for decision making.
When it launches this year, the NISAR (NASA-ISRO Synthetic Aperture Radar) satellite will provide a powerful data stream that could help farmers in the U.S. and around the world. This new Earth mission by NASA and the Indian Space Research Organisation will help monitor the growth of crops from planting to harvest, generating crucial insights on how to time plantings, adjust irrigation schedules, and, ultimately, make the most of another precious resource: time.
Using synthetic aperture radar, NISAR will discern the physical characteristics of crops, as well as the moisture content of the plants and the soil they grow in. The mission will have the resolution to see small plots of farmland, but a potentially more meaningful benefit will come from its broad, frequent coverage of agricultural regions.
The satellite will image nearly all of Earth’s land twice every 12 days and will be able to resolve plots down to 30 feet (10 meters) wide. The cadence and resolution could allow users to zoom in to observe week-to-week changes on small farms or zoom out to monitor thousands of farms for broader trends. Such big-picture perspective will be useful for authorities managing crops or setting farm policy.
Tapping NISAR data, decision-makers could, for example, estimate when rice seedlings were planted across a region and track their height and blooming through the season while also monitoring the wetness of the plants and paddies over time. An unhealthy crop or drier paddies may signal the need to shift management strategies.
NISAR will provide maps of croplands on a global basis every two weeks. Observations will be uninterrupted by weather and provide up-to-date information on the large-scale trends that affect international food security. Credit: NASA/JPL-Caltech “It’s all about resource planning and optimizing, and timing is very important when it comes to crops: When is the best time to plant? When is the best time to irrigate? That is the whole game here,” said Narendra Das, a NISAR science team member and agricultural engineering researcher at Michigan State University in East Lansing.
Mapping Crops
NISAR is set to launch this year from ISRO’s Satish Dhawan Space Centre on India’s southeastern coast. Once in operation, it will produce about 80 terabytes of data products per day for researchers and users across numerous areas, including agriculture.
Satellites have been used for large-scale crop monitoring for decades. Because microwaves pass through clouds, radar can be more effective at observing crops during rainy seasons than other technologies such as thermal and optical imaging. The NISAR satellite will be the first radar satellite to employ two frequencies, L- and S-band, which will enable it to observe a broader range of surface features than a single instrument working at one frequency.
Microwaves from the mission’s radars will be able to penetrate the canopies of crops such as corn, rice, and wheat, then bounce off the plant stalks, soil, or water below, and then back to the sensor. This data will enable users to estimate the mass of the plant matter (biomass) that’s aboveground in an area. By interpreting the data over time and pairing it with optical imagery, users will be able to distinguish crop types based on growth patterns.
Data gathered in 2017 by the European Sentinel-1 SAR satellite program shows changes to croplands in the region southeast of Florida’s Lake Okeechobee. Colors in the fields indicate various crops in different parts of their growth and harvest cycles. NISAR will gather similar data in L- and S-band radar frequencies.ESA; processing and visualization by Earth Big Data LLC Additionally, NISAR’s radars will measure how the polarization, or vertical and horizontal orientation of signals, changes after they bounce back to the satellite from the surface. This will enable a technique called polarimetry that, when applied to the data, will help identify crops and estimate crop production with better accuracy.
“Another superpower of NISAR is that when its measurements are integrated with traditional satellite observations, especially vegetation health indexes, it will significantly enhance crop information,” added Brad Doorn, who oversees NASA’s water resources and agriculture research program.
The NISAR satellite’s high-resolution data on which crops are present and how well they are growing could feed into agricultural productivity forecasts.
“The government of India — or any government in the world — wants to know the crop acreage and the production estimates in a very precise way,” said Bimal Kumar Bhattacharya, the agricultural applications lead at ISRO’s Space Applications Centre in Ahmedabad. “The high-repeat time-series data of NISAR will be very, very helpful.”
Tracking Soil Moisture
The NISAR satellite can also help farmers gauge the water content in soil and vegetation. In general, wetter soils tend to return more signals and show up brighter in radar imagery than drier soils. There is a similar relationship with plant moisture.
A collaboration between NASA and the Indian Space Research Organisation, NISAR will use synthetic aperture radar to offer insights into change in Earth’s ecosystems, including its agricultural lands. The spacecraft, depicted here in an artist’s concept, will launch from India.NASA/JPL-Caltech These capabilities mean that NISAR can estimate the water content of crops over a growing season to help determine if they are water-stressed, and it can use signals that have scattered back from the ground to estimate soil moisture.
The soil moisture data could potentially inform agriculture and water managers about how croplands respond to heat waves or droughts, as well as how quickly they absorb water and then dry out following rain — information that could support irrigation planning.
“Resource managers thinking about food security and where resources need to go are going to be able to use this sort of data to have a holistic view of their whole region,” said Rowena Lohman, an Earth sciences researcher at Cornell University in Ithaca, New York, and soil moisture lead on the NISAR science team.
More About NISAR
The NISAR satellite is a joint collaboration between NASA and ISRO and marks the first time the two agencies have cooperated on flight hardware for an Earth-observing mission. Managed by Caltech, NASA’s Jet Propulsion Laboratory leads the U.S. component of the project and provided the L-band SAR. NASA JPL also provided the radar reflector antenna, the deployable boom, a high-rate communication subsystem for science data, GPS receivers, a solid-state recorder, and payload data subsystem. NASA’s Goddard Space Flight Center manages the Near Space Network, which will receive NISAR’s L-band data.
The ISRO Space Applications Centre is providing the mission’s S-band SAR. The U R Rao Satellite Centre provided the spacecraft bus. The launch vehicle is from Vikram Sarabhai Space Centre, launch services are through Satish Dhawan Space Centre, and satellite mission operations are by the ISRO Telemetry Tracking and Command Network. The National Remote Sensing Centre is responsible for S-band data reception, operational products generation, and dissemination.
To learn more about NISAR, visit:
https://nisar.jpl.nasa.gov
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Curiosity Navigation Curiosity Home Mission Overview Where is Curiosity? Mission Updates Science Overview Instruments Highlights Exploration Goals News and Features Multimedia Curiosity Raw Images Images Videos Audio Mosaics More Resources Mars Missions Mars Sample Return Mars Perseverance Rover Mars Curiosity Rover MAVEN Mars Reconnaissance Orbiter Mars Odyssey More Mars Missions Mars Home 2 min read
Sols 4477-4478: Bumping Back to Business
NASA’s Mars rover Curiosity acquired this image using its Right Navigation Camera on March 10, 2025 — sol 4476, or Martian day 4,476 of the Mars Science Laboratory mission — at 04:15:44 UTC. NASA/JPL-Caltech Written by Sharon Wilson Purdy, Planetary Geologist at the Smithsonian National Air and Space Museum
Earth planning date: Monday, March 10, 2025
The Curiosity rover is winding between the spectacular Gould mesa and Texoli butte through beautifully layered terrain. The end-of-drive target from last week’s plan was a rock with a knobby/bumpy texture that appears quite different from the typical surrounding bedrock. While this interesting rock was in our workspace today, we ended up being just a touch too close to do contact science. As a result, the science team decided to “bump back” (e.g., drive backwards) to get the rover in an ideal position to analyze and characterize this rock on Wednesday.
In the middle of the rover’s workspace today there was a large patch of soil and sand that MAHLI and APXS teamed up to analyze at a target named “Angeles Crest.” Nearby, Mastcam imaged troughs (depressions) along the axis of the sand ridge to understand how they formed. Mastcam had several other targets in the plan that imaged the workspace and surroundings including “Potrero John,” the knobby rock in the workspace, a rock with similar nodular textures in the distance named “Modjeska Peak,” and a light tan rock with a dome-like structure in the vicinity of “Humber Park.”
ChemCam selected a slab of bedrock and loose (“float”) rock in the workspace to characterize their geochemistry with the LIBS instrument at “Millard Canyon” and “Cajon Pass,” respectively. Off in the distance, the science team selected the face of Gould mesa and upper Texoli butte for ChemCam long distance RMI imaging to get a closer look at the rocks, fractures, and layering.
The environmental theme group scheduled several activities to look at clouds, document the atmospheric opacity, and measure the optical depth of the atmosphere and constrain aerosol scattering properties. We have lots of exciting data in hand and more on the road ahead!
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