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As the Arctic Warms, Its Waters Are Emitting Carbon


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Sediment from Canada’s Mackenzie River empties into the Beaufort Sea in milky swirls in this 2017 satellite image. Scientists are studying how river discharge drives carbon dioxide emissions in this part of the Arctic Ocean.
Sediment from Canada’s Mackenzie River empties into the Beaufort Sea in milky swirls in this 2017 satellite image. Scientists are studying how river discharge drives carbon dioxide emissions in this part of the Arctic Ocean.
NASA Earth Observatory image by Jesse Allen using Landsat data from USGS

Runoff from one of North America’s largest rivers is driving intense carbon dioxide emissions in the Arctic Ocean.

When it comes to influencing climate change, the world’s smallest ocean punches above its weight. It’s been estimated that the cold waters of the Arctic absorb as much as 180 million metric tons of carbon per year – more than three times what New York City emits annually – making it one of Earth’s critical carbon sinks. But recent findings show that thawing permafrost and carbon-rich runoff from Canada’s Mackenzie River trigger part of the Arctic Ocean to release more carbon dioxide (CO2) than it absorbs.

The study, published earlier this year, explores how scientists are using state-of-the-art computer modeling to study rivers such as the Mackenzie, which flows into a region of the Arctic Ocean called the Beaufort Sea. Like many parts of the Arctic, the Mackenzie River and its delta have faced significantly warmer temperatures in recent years across all seasons, leading to more melting and thawing of waterways and landscapes.

In this marshy corner of Canada’s Northwest Territories, the continent’s second largest river system ends a thousand-mile journey that begins near Alberta. Along the way, the river acts as a conveyor belt for mineral nutrients as well as organic and inorganic matter. That material drains into the Beaufort Sea as a soup of dissolved carbon and sediment. Some of the carbon is eventually released, or outgassed, into the atmosphere by natural processes.

Scientists have thought of the southeastern Beaufort Sea as a weak-to-moderate CO2 sink, meaning it absorbs more of the greenhouse gas than it releases. But there has been great uncertainty due to a lack of data from the remote region.

To fill that void, the study team adapted a global ocean biogeochemical model called ECCO-Darwin, which was developed at NASA’s Jet Propulsion Laboratory in Southern California and the Massachusetts Institute of Technology in Cambridge. The model assimilates nearly all available ocean observations collected for more than two decades by sea- and satellite-based instruments (sea level observations from the Jason-series altimeters, for example, and ocean-bottom pressure from the GRACE and GRACE Follow-On missions).

Like a conveyer belt of carbon, the Mackenzie River, seen here in 2007 from NASA’s Terra satellite, drains an area of almost 700,000 square miles (1.8 million square kilometers) on its journey north to the Arctic Ocean. Some of the carbon originates from thawing permafrost and peatlands.
Like a conveyer belt of carbon, the Mackenzie River, seen here in 2007 from NASA’s Terra satellite, drains an area of almost 700,000 square miles (1.8 million square kilometers) on its journey north to the Arctic Ocean. Some of the carbon originates from thawing permafrost and peatlands.
NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

The scientists used the model to simulate the discharge of fresh water and the elements and compounds it carries – including carbon, nitrogen, and silica – across nearly 20 years (from 2000 to 2019).

The researchers, from France, the U.S., and Canada, found that the river discharge was triggering such intense outgassing in the southeastern Beaufort Sea that it tipped the carbon balance, leading to a net CO2 release of 0.13 million metric tons per year – roughly equivalent to the annual emissions from 28,000 gasoline-powered cars. The release of CO2 into the atmosphere varied between seasons, being more pronounced in warmer months, when river discharge was high and there was less sea ice to cover and trap the gas.

Ground Zero for Climate Change

Scientists have for decades studied how carbon cycles between the open ocean and atmosphere, a process called air-sea CO2 flux. However, the observational record is sparse along the coastal fringes of the Arctic, where the terrain, sea ice, and long polar nights can make long-term monitoring and experiments challenging.

“With our model, we are trying to explore the real contribution of the coastal peripheries and rivers to the Arctic carbon cycle,” said lead author Clément Bertin, a scientist at Littoral Environnement et Sociétés in France.

Such insights are critical because about half of the area of the Arctic Ocean is composed of coastal waters, where land meets sea in a complex embrace. And while the study focused on a particular corner of the Arctic Ocean, it can help tell a larger story of environmental change unfolding in the region.

Since the 1970s, the Arctic has warmed at least three times faster than anywhere else on Earth, transforming its waters and ecosystems, the scientists said. Some of these changes promote more CO2 outgassing in the region, while others lead to more CO2 being absorbed.

For example, with Arctic lands thawing and more snow and ice melting, rivers are flowing more briskly and flushing more organic matter from permafrost and peatlands into the ocean. On the other hand, microscopic phytoplankton floating near the ocean surface are increasingly taking advantage of shrinking sea ice to bloom in the newfound open water and sunlight. These plantlike marine organisms capture and draw down atmospheric CO2during photosynthesis. The ECCO-Darwin model is being used to study these blooms and the ties between ice and life in the Arctic.

Scientists are tracking these large and seemingly small changes in the Arctic and beyond because our ocean waters remain a critical buffer against a changing climate, sequestering as much as 48% of the carbon produced by burning fossil fuels.

News Media Contacts

Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 818-354-0307
andrew.wang@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov

Written by Sally Younger

2023-185

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      Photo 9. The BlueFlux airborne science team collects flux measurements from 90m (300ft) above Florida’s mangrove forests. Photo credit: Nathan Marder/NASA’s Goddard Space Flight Center (GSFC) Data Upscaling – Making Daily Flux Predictions from Space
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      “We’re really at the mercy of the data that’s out there,” said Doughty. “One of the things we’re trying to produce as part of this project is a daily archive of fluxes, so MODIS is an amazing resource, because it has over 20 years of data at a daily temporal resolution.”
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      From Drainage to Restoration in the Florida Everglades
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      Photo 10. The Tamiami Trail Canal runs across the Florida Peninsula from west to east, towards a saltwater treatment facility near the Miami River. Construction was completed in 1928, shortly after the first four drainage canals opened. It quickly became apparent that the canal and its adjacent roadway dramatically impede water flow to the Everglades wilderness areas to their south, cutting off the region’s vegetation and wildlife from a critical source of freshwater. New modifications to the canal are currently underway, which aim to introduce a hydrological regime that more closely resembles the pre-drainage system. Photo credit: U.S. National Park Service Florida’s Water Management District works with federal agencies, including the U.S. Army Corps of Engineers, to monitor and govern the flow of Florida’s freshwater. The District has overseen the construction and management of dozens of canals, dikes, levees, dredges, and pumps over the last half-century that offer a higher degree of control over Florida’s complex hydrological network – see Photo 10.
      “The goal is to restore as much acreage as we can, but we also need to restore it functionally, without degrading the whole system or putting residents at risk,” summarized Sklar. “To do this effectively, we need a detailed understanding of how the hydrology functions and how it influences all of these other systems, such as carbon sequestration.”
      Since the 1920s, more than half of Florida’s original wetland coverage has been lost. The present system also carries 65% less peat coverage and 77% less stored carbon than it did prior to drainage. As atmospheric CO2 concentrations climb at unprecedented rates, an accompanying rise in sea levels, severe weather, and ocean salinity all present serious threats to Florida’s wetland ecology – see Figure 5.
      “We’re worried about losing that stored carbon,” said Poulter. “But blue carbon also offers tremendous opportunities for climate mitigation if conservation and restoration are properly supported by science.”
      Figure 5. A map of the BlueFlux study region, showing mangrove extent (green) and the paths of tropical storms and hurricanes from 2011 to 2021 (red). These storms drive losses in mangrove forest coverage – the result of erosion and wind damage. The inset regions at the top of the image highlight proposed targets for the airborne component of NASA’s BlueFlux Campaign. Figure credit: GSFC Conclusion – The Future of Flux
      Every few years, the Intergovernmental Panel on Climate Change (IPCC) releases emissions data and budget reports that have important policy implications related to the Paris Agreement’s goal of limiting global warming to between 1.5°C (2.7°F) and 2°C (3.6°F) compared to pre-industrial levels. Refining the accuracy of global carbon budgets is paramount to reaching that goal, and wetland ecosystems – which have been historically under-represented in climate research – are an important part of the equation.
      Early estimates based on BlueFlux fieldwork deployments and upscaled using MODIS surface reflectance data suggest that wetland CH4 emissions in South Florida offset CO2 removal in the region by about 5% based on a 100-year CH4 warming potential, resulting in a net annual CO2 removal of 31.8 Tg (3.18 million metric tons) per year. This is a small fraction of total CO2 emissions in the U.S. and an even smaller fraction of global emissions. In 2023, an estimated 34,800 Tg (34.8 billion metric tons) of CO2 were released into the atmosphere. But relative to their size, the CO2 removal services provided by tropical wetlands are hardly dismissible.
      “We’re finding that massive amounts of CO2 are removed and substantial amounts of CH4 are produced, but overall, these ecosystems provide a net climate benefit by removing more greenhouse gases than they produce,” Poulter said.
      Access to a daily satellite data product also provides researchers with the means to make more regular adjustments to budgets based on how Florida’s mutable landscape is responding to climate disturbances and restoration efforts in real time.
      With the right resources in hand, the scientists who dedicate their careers to understanding and restoring South Florida’s ecology share a hopeful outlook.
      “Nature and people can absolutely coexist,” said Meenakshi Chabba [The Everglades Foundation—Ecologist and Resilience Scientist]. “But what we need is good science and good management to reach that goal.”
      The Everglades Foundation provides scientific evaluation and guidance to the elected officials and governmental institutions responsible for the implementation of the Comprehensive Everglades Restoration Plan (CERP), a federal program approved by Congress in 2000 that outlines a 30-year plan to restore Florida’s wetland ecology. The Foundation sees NASA’s BlueFlux campaign as an important accompaniment to that goal.
      “The [Daily Flux Predictions for South Florida] data product is incredibly valuable, because it provides us with an indicator of the health of the whole system,” said Steve Davis [The Everglades Foundation—Chief Science Officer]. “We know how valuable the wetlands are, but we need this reliable science from NASA and the BlueFlux Campaign to help translate those benefits into something we can use to reach people as well as policymakers.”
      Researchers hope the product can inform decisions about the management of Florida’s wetlands, the preservation of which is not only a necessity but – to many – a responsibility.
      “These impacts are of our own doing,” added Chabba. “So, now it’s incumbent upon us to make these changes and correct the mistakes of the past.”
      Next, the BlueFlux team is shifting their focus to what they call BlueFlux 2. This stage of the project centers around further analysis of the data collected during fieldwork campaigns and outlines the deployment of the beta version of Daily BlueFlux Predictions for South Florida, which will help generate a more accurate evaluation of flux for the many wetland ecosystems that exist beyond Florida’s borders.
      “We’re trying to contribute to a better understanding of global carbon markets and inspire further and more ambitious investments in these critical stocks of blue carbon,” said Poulter. “First, we want to scale this work to the Caribbean, where we have these great maps of mangrove distribution but limited data on flux.”
      An additional BlueFlux fieldwork deployment is slated for 2026, with plans to make flux measurements above sites targeted by the state for upcoming restoration initiatives, such as the Everglades Agricultural Area Environmental Protection District. In the Agricultural Area, construction is underway on a series of reservoirs that will store excess water during wet seasons and provide a reserve source of water for wildlife and residents during dry seasons. As the landscape evolves, BlueFlux will help local officials evaluate how Florida’s wetlands are responding to efforts designed to protect the state’s most precious natural resource – and all those who depend on it. 
      Nathan Marder
      NASA’s Goddard Space Flight Center/Global Science and Technology Inc.
      nathan.marder@nasa.gov
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      Last Updated Nov 12, 2024 Related Terms
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    • By NASA
      4 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      NASA’s X-59 quiet supersonic research aircraft sits in its run stall at Lockheed Martin’s Skunk Works facility in Palmdale, California, firing up its engine for the first time. These engine-run tests start at low power and allow the X-59 team to verify the aircraft’s systems are working together while powered by its own engine. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land by making sonic booms quieter.NASA/Carla Thomas NASA’s Quesst mission marked a major milestone with the start of tests on the engine that will power the quiet supersonic X-59 experimental aircraft.
      These engine-run tests, which began Oct. 30, allow the X-59 team to verify the aircraft’s systems are working together while powered by its own engine. In previous tests, the X-59 used external sources for power. The engine-run tests set the stage for the next phase of the experimental aircraft’s progress toward flight.
      The X-59 team is conducting the engine-run tests in phases. In this first phase, the engine rotated at a relatively low speed without ignition to check for leaks and ensure all systems are communicating properly. The team then fueled the aircraft and began testing the engine at low power, with the goal of verifying that it and other aircraft systems operate without anomalies or leaks while on engine power.
      Lockheed Martin test pilot Dan Canin sits in the cockpit of NASA’s X-59 quiet supersonic research aircraft in a run stall at Lockheed Martin’s Skunk Works facility in Palmdale, California prior to its first engine run. These engine-run tests featured the X-59 powered by its own engine, whereas in previous tests, the aircraft depended on external sources for power. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land by making sonic booms quieter.NASA/Carla Thomas “The first phase of the engine tests was really a warmup to make sure that everything looked good prior to running the engine,” said Jay Brandon, NASA’s X-59 chief engineer. “Then we moved to the actual first engine start. That took the engine out of the preservation mode that it had been in since installation on the aircraft. It was the first check to see that it was operating properly and that all the systems it impacted – hydraulics, electrical system, environmental control systems, etc. – seemed to be working.”
      The X-59 will generate a quieter thump rather than a loud boom while flying faster than the speed of sound. The aircraft is the centerpiece of NASA’s Quesst mission, which will gather data on how people perceive these thumps, providing regulators with information that could help lift current bans on commercial supersonic flight over land.
      The engine, a modified F414-GE-100, packs 22,000 pounds of thrust, which will enable the X-59 to achieve the desired cruising speed of Mach 1.4 (925 miles per hour) at an altitude of approximately 55,000 feet. It sits in a nontraditional spot – atop the aircraft — to aid in making the X-59 quieter.
      Engine runs are part of a series of integrated ground tests needed to ensure safe flight and successful achievement of mission goals. Because of the challenges involved with reaching this critical phase of testing, the X-59’s first flight is now expected in early 2025. The team will continue progressing through critical ground tests and address any technical issues discovered with this one-of-a-kind, experimental aircraft. The X-59 team will have a more specific first flight date as these tests are successfully completed.
      The testing is taking place at Lockheed Martin’s Skunk Works facility in Palmdale, California. During later phases, the team will test the aircraft at high power with rapid throttle changes, followed by simulating the conditions of an actual flight.
      NASA’s X-59 quiet supersonic research aircraft sits in its run stall at Lockheed Martin’s Skunk Works facility in Palmdale, California, prior to its first engine run. Engine runs are part of a series of integrated ground tests needed to ensure safe flight and successful achievement of mission goals. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land by making sonic booms quieter.NASA/Carla Thomas “The success of these runs will be the start of the culmination of the last eight years of my career,” said Paul Dees, NASA’s deputy propulsion lead for the X-59. “This isn’t the end of the excitement but a small steppingstone to the beginning. It’s like the first note of a symphony, where years of teamwork behind the scenes are now being put to the test to prove our efforts have been effective, and the notes will continue to play a harmonious song to flight.”
      After the engine runs, the X-59 team will move to aluminum bird testing, where data will be fed to the aircraft under both normal and failure conditions. The team will then proceed with a series of taxi tests, where the aircraft will be put in motion on the ground. These tests will be followed by final preparations for first flight.
      Facebook logo @NASA@NASAaero@NASA_es @NASA@NASAaero@NASA_es Instagram logo @NASA@NASAaero@NASA_es Linkedin logo @NASA Explore More
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      Last Updated Nov 06, 2024 EditorLillian GipsonContactMatt Kamletmatthew.r.kamlet@nasa.gov Related Terms
      Aeronautics Aeronautics Research Mission Directorate Ames Research Center Armstrong Flight Research Center Glenn Research Center Langley Research Center Low Boom Flight Demonstrator Quesst (X-59) Quesst: The Vehicle Supersonic Flight View the full article
    • By NASA
      The SpaceX Dragon spacecraft carrying NASA astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov approaches the International Space Station as it orbits 259 miles above Oregon.Credit: NASA In preparation for the arrival of NASA’s SpaceX 31st commercial resupply services mission, four crew members aboard the International Space Station will relocate the agency’s SpaceX Crew-9 Dragon spacecraft to a different docking port Sunday, Nov. 3.
      Live coverage begins at 6:15 a.m. EDT on NASA+ and will end shortly after docking. Learn how to watch NASA content through a variety of platforms, including social media. 
      NASA astronauts Nick Hague, Suni Williams, and Butch Wilmore, as well as Roscosmos cosmonaut Aleksandr Gorbunov, will undock the spacecraft from the forward-facing port of the station’s Harmony module at 6:35 a.m., and redock to the module’s space-facing port at 7:18 a.m.
      The relocation, supported by flight controllers at NASA’s Johnson Space Center in Houston and the Mission Control team at SpaceX in Hawthorne, California, will free Harmony’s forward-facing port for a Dragon cargo spacecraft mission scheduled to launch no earlier than Monday, Nov. 4.
      This will be the fifth port relocation of a Dragon spacecraft with crew aboard following previous moves during the Crew-1, Crew-2, Crew-6, and Crew-8 missions.
      Learn more about space station activities by following @space_station and @ISS_Research on X, as well as the ISS Facebook, ISS Instagram, and the space station blog.
      NASA’s SpaceX Crew-9 mission launched Sept. 28 from NASA’s Kennedy Space Center in Florida and docked to the space station Sept. 29. Crew-9, targeted to return February 2025, is the company’s ninth rotational crew mission as a part of the agency’s Commercial Crew Program.
      Find NASA’s commercial crew blog and more information about the Crew-9 mission at:
      https://www.nasa.gov/commercialcrew
      -end-
      Jimi Russell / Claire O’Shea
      Headquarters, Washington
      202-358-1100
      james.j.russell@nasa.gov / claire.a.o’shea@nasa.gov
      Sandra Jones
      Johnson Space Center, Houston
      281-483-5111
      sandra.p.jones@nasa.gov
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      Last Updated Oct 29, 2024 EditorJessica TaveauLocationNASA Headquarters Related Terms
      Commercial Crew Humans in Space International Space Station (ISS) Johnson Space Center Kennedy Space Center View the full article
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