An Ocean in Motion: NASA’s Mesmerizing View of Earth’s Underwater Highways
1 min read
An Ocean in Motion: NASA’s Mesmerizing View of Earth’s Underwater Highways
This data visualization showing ocean currents around the world uses data from NASA’s ECCO model, or Estimating the Circulation and Climate of the Ocean. The model pulls data from spacecraft, buoys, and other measurements.
Going With the Flow: Visualizing Ocean Currents with ECCO
8 Min Read
Going With the Flow: Visualizing Ocean Currents with ECCO
The North American Gulf Stream as illustrated with the ECCO model.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Historically, the ocean has been difficult to model. Scientists struggled in years past to simulate ocean currents or accurately predict fluctuations in temperature, salinity, and other properties. As a result, models of ocean dynamics rapidly diverged from reality, which meant they could only provide useful information for brief periods.
In 1999, a project called Estimating the Circulation and Climate of the Ocean (ECCO) changed all that. By applying the laws of physics to data from multiple satellites and thousands of floating sensors, NASA scientists and their collaborators built ECCO to be a realistic, detailed, and continuous ocean model that spans decades. ECCO enabled thousands of scientific discoveries, and was featured during the announcement of the Nobel Prize for Physics in 2021.
NASA ECCO is a powerful integrator of decades of ocean data, narrating the story of Earth’s changing ocean as it drives our weather, and sustains marine life.
The ECCO project includes hundreds of millions of real-world measurements of temperature, salinity, sea ice concentration, pressure, water height, and flow in the world’s oceans. Researchers rely on the model output to study ocean dynamics and to keep tabs on conditions that are crucial for ecosystems and weather patterns. The modeling effort is supported by NASA’s Earth science programs and by the international ECCO consortium, which includes researchers from NASA’s Jet Propulsion Laboratory in Southern California and eight research institutions and universities.
The project provides models that are the best possible reconstruction of the past 30 years of the global ocean. It allows us to understand the ocean’s physical processes at scales that are not normally observable.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Large-scale wind patterns around the globe drag ocean surface waters with them, creating complex currents, including some that flow toward the western sides of the ocean basins. The currents hug the eastern coasts of continents as they head north or south from the equator: These are the western boundary currents. The three most prominent are the Gulf Stream, Agulhas, and Kuroshio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Seafarers have known about the Gulf Stream — the Atlantic Ocean’s western boundary current — for more than 500 years. By the volume of water it moves, the Gulf Stream is the largest of the western boundary currents, transporting more water than all the planet’s rivers combined.
In 1785, Benjamin Franklin added it to maritime charts showing the current flowing up from the Gulf, along the eastern U.S. coast, and out across the North Atlantic. Franklin noted that riding the current could improve a ship’s travel time from the Americas to Europe, while avoiding the current could shorten travel times when sailing back.
A visualization built of ECCO data reveals a cold, deep countercurrent that flows in the opposite direction of the warm Gulf Stream above it. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Franklin’s charts showed a smooth Gulf Stream rather than the twisted, swirling path revealed in ECCO data. And Franklin couldn’t have imagined the opposing flow of water below the Gulf Stream. The countercurrent runs at depths of about 2,000 feet (600 meters) in a cold river of water that is roughly the opposite of the warm Gulf Stream at the surface. The submarine countercurrent is clearly visible when the upper layers in the ECCO model are peeled away in visualizations.
The Gulf Stream is a part of the Atlantic Meridional Overturning Circulation (AMOC), which moderates climate worldwide by transporting warm surface waters north and cool underwater currents south. The Gulf Stream, in particular, stabilizes temperatures of the southeastern United States, keeping the region warmer in winter and cooler in summer than it would be without the current. After the Gulf Stream crosses the Atlantic, it tempers the climates of England and the European coast as well.
The Agulhas current originates along the equator in the Indian Ocean, travels down the western coast of Africa, and spawns swirling Agulhas rings that travel across the Atlantic toward South America. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
The Agulhas Current flows south along the western side of the Indian Ocean. When it reaches the southern tip of Africa, it sheds swirling vortices of water called Agulhas Rings. Sometimes persisting for years, the rings glide across the Atlantic toward South America, transporting small fish, larvae, and other microorganisms from the Indian Ocean.
Researchers using the ECCO model can study Agulhas Current flow as it sends warm, salty water from the tropics in the Indian Ocean toward the tip of South Africa. The model helps tease out the complicated dynamics that create the Agulhas rings and large loop of current called a supergyre that surrounds the Antarctic. The Southern Hemisphere supergyre links the southern portions of other, smaller current loops (gyres) that circulate in the southern Atlantic, Pacific, and Indian oceans. Together with gyres in the northern Atlantic and Pacific, the southern gyres and Southern Hemisphere supergyre influence climate while transporting carbon around the globe.
The Kuroshio Current flows on the western side of the Pacific Ocean, past the east coast of Japan, east across the Pacific, and north toward the Arctic. Along the way, it provides warm water to drive seasonal storms, while also creating ocean upwellings that carry nutrients that sustain fisheries off the coasts of Taiwan and northern Japan. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
In addition to affecting global weather patterns and temperatures, western boundary currents can drive vertical flows in the oceans known as upwellings. The flows bring nutrients up from the depths to the surface, where they act as fertilizer for phytoplankton, algae, and aquatic plants.
The Kuroshio Current that runs on the west side of the Pacific Ocean and along the east side of Japan has recently been associated with upwellings that enrich coastal fishing waters. The specific mechanisms that cause the vertical flows are not entirely clear. Ocean scientists are now turning to ECCO to tease out the connection between nutrient transport and currents like the Kuroshio that might be revealed in studies of the water temperature, density, pressure, and other factors included in the ECCO model.
Tracking Ocean Temperatures and Salinity
When viewed through the lens of ECCO’s temperature data, western boundary currents carry warm water away from the tropics and toward the poles. In the case of the Gulf Stream, as the current moves to far northern latitudes, some of the saltwater freezes into salt-free sea ice. The saltier water left behind sinks and then flows south all the way toward the Antarctic before rising and warming in other ocean basins.
Colors indicate temperature in this visualization of ECCO data. Warm water near the equator is bright yellow. Water cools when it flows toward the poles, indicated by the transition to orange and red shades farther from the equator. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Currents also move nutrients and salt throughout Earth’s ocean basins. Swirling vortexes of the Agulhas rings stand out in ECCO temperature and salinity maps as they move warm, salty water from the Indian Ocean into the Atlantic.
The Mediterranean Sea has a dark red hue that indicates its high salt content. Other than the flow through the narrow Strait of Gibraltar, the Mediterranean is cut off from the rest of the world’s oceans. Because of this restricted flow, salinity increases in the Mediterranean as its waters warm and evaporate, making it one of the saltiest parts of the global ocean. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Greg Shirah/NASA’s Scientific Visualization Studio
Experimenting with ECCO
ECCO offers researchers a way to run virtual experiments that would be impractical or too costly to perform in real oceans. Some of the most important applications of the ECCO model are in ocean ecology, biology, and chemistry. Because the model shows where the water comes from and where it goes, researchers can see how currents transport heat, minerals, nutrients, and organisms around the planet.
In prior decades, for example, ocean scientists relied on extensive temperature and salinity measurements by floating sensors to deduce that the Gulf Stream is primarily made of water flowing past the Gulf rather than through it. The studies were time-consuming and expensive. With the ECCO model, data visualizers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, virtually replicated the research in a simulation that was far quicker and cheaper.
A simulation built with data from the ECCO model shows that very little of the water in the gulf contributes to the water flowing in the Gulf Stream. Download this visualization from NASA Goddard’s Scientific Visualization Studio.
Credits: Atousa Saberi/NASA’s Scientific Visualization Studio
The example illustrated here relies on ECCO to track the flow of water by virtually filling the Gulf with 115,000 particles and letting them move for a year in the model. The demonstration showed that less than 1% of the particles escape the Gulf to join the Gulf Stream.
Running such particle-tracking experiments within the ocean circulation models helps scientists understand how and where environmental contaminants, such as oil spills, can spread.
Take an ECCO Deep Dive
Today, researchers turn to ECCO for a broad array of studies. They can choose ECCO modeling products that focus on one feature – such as global flows or the biology and chemistry of the ocean – or they can narrow the view to the poles or specific ocean regions. Every year, more than a hundred scientific papers include data and analyses from the ECCO model that delve into our oceans’ properties and dynamics.
Credits: Kathleen Gaeta Greer/ NASA’s Scientific Visualization Studio
Composed by James Riordon / NASA’s Earth Science News Team
Information in this piece came from the resources below and interviews with the following sources: Nadya Vinogradova Shiffer, Dimitris Menemenlis, Ian Fenty, and Atousa Saberi.
References and Sources
Liao, F., Liang, X., Li, Y., & Spall, M. (2022). Hidden upwelling systems associated with major western boundary currents. Journal of Geophysical Research: Oceans, 127(3), e2021JC017649.
Richardson, P. L. (1980). The Benjamin Franklin and Timothy Folger charts of the Gulf Stream. In Oceanography: The Past: Proceedings of the Third International Congress on the History of Oceanography, held September 22–26, 1980 at the Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA on the occasion of the Fiftieth Anniversary of the founding of the Institution (pp. 703-717). New York, NY: Springer New York.
Biastoch, A., Rühs, S., Ivanciu, I., Schwarzkopf, F. U., Veitch, J., Reason, C., … & Soltau, F. (2024). The Agulhas Current System as an Important Driver for Oceanic and Terrestrial Climate. In Sustainability of Southern African Ecosystems under Global Change: Science for Management and Policy Interventions (pp. 191-220). Cham: Springer International Publishing.
Lee-Sánchez, E., Camacho-Ibar, V. F., Velásquez-Aristizábal, J. A., Valencia-Gasti, J. A., & Samperio-Ramos, G. (2022). Impacts of mesoscale eddies on the nitrate distribution in the deep-water region of the Gulf of Mexico. Journal of Marine Systems, 229, 103721.
NASA Names Norman Knight as Acting Deputy Director of Johnson Space Center
Official NASA portrait of Norman D. Knight.
Credit: NASA
NASA has selected Norman Knight as acting deputy director of Johnson Space Center. Knight currently serves as Director of Johnson’s Flight Operations Directorate (FOD), responsible for astronaut training and for overall planning, directing, managing, and implementing overall mission operations for NASA human spaceflight programs. This also includes management for all Johnson aircraft operations and aircrew training. Knight will serve in this dual deputy director and FOD director role for the near term.
Knight began his career at the Johnson Space Center as a Space Shuttle mechanical systems flight controller, working 40 missions in this capacity. He progressed through management roles with increasing responsibility, and in 2000, he was selected as a flight director and worked in that capacity for numerous International Space Station expeditions and Space Shuttle missions. In 2009, he became the deputy chief of the Flight Director Office and participated in a NASA fellowship at Harvard Business School in general management. In 2012, Knight was selected as the chief of the Flight Director Office and then in 2018 as deputy director of the Flight Operations Directorate after serving a temporary assignment as the assistant administrator, Human Exploration and Operations Mission Directorate at NASA Headquarters. In 2021, Knight was selected as the director of FOD.
Throughout his career, Knight has been recognized for outstanding technical achievements and leadership, receiving a Spaceflight Awareness Honoree award for STS-82. He also received several center and agency awards, including two Exceptional Achievement medals, multiple Johnson and agency group achievement awards, two Superior Accomplishment awards, an Outstanding Leadership medal, the Johnson Director’s Commendation award, and the Distinguished Service medal.
Knight earned a bachelor’s degree in aeronautical engineering from the Embry Riddle Aeronautical University in 1990.
NASA’s Webb Exposes Complex Atmosphere of Starless Super-Jupiter
6 Min Read
NASA’s Webb Exposes Complex Atmosphere of Starless Super-Jupiter
This artist’s concept shows what the isolated planetary-mass object SIMP 0136 could look like based on recent observations from NASA’s James Webb Space Telescope and previous observations from Hubble, Spitzer, and numerous ground-based telescopes.
Credits: NASA, ESA, CSA, and Joseph Olmsted (STScI)
An international team of researchers has discovered that previously observed variations in brightness of a free-floating planetary-mass object known as SIMP 0136 must be the result of a complex combination of atmospheric factors, and cannot be explained by clouds alone.
Using NASA’s James Webb Space Telescope to monitor a broad spectrum of infrared light emitted over two full rotation periods by SIMP 0136, the team was able to detect variations in cloud layers, temperature, and carbon chemistry that were previously hidden from view.
The results provide crucial insight into the three-dimensional complexity of gas giant atmospheres within and beyond our solar system. Detailed characterization of objects like these is essential preparation for direct imaging of exoplanets, planets outside our solar system, with NASA’s Nancy Grace Roman Space Telescope, which is scheduled to begin operations in 2027.
Rapidly Rotating, Free-Floating
SIMP 0136 is a rapidly rotating, free-floating object roughly 13 times the mass of Jupiter, located in the Milky Way just 20 light-years from Earth. Although it is not classified as a gas giant exoplanet — it doesn’t orbit a star and may instead be a brown dwarf — SIMP 0136 is an ideal target for exo-meteorology: It is the brightest object of its kind in the northern sky. Because it is isolated, it can be observed with no fear of light contamination or variability caused by a host star. And its short rotation period of just 2.4 hours makes it possible to survey very efficiently.
Prior to the Webb observations, SIMP 0136 had been studied extensively using ground-based observatories and NASA’s Hubble and Spitzer space telescopes.
“We already knew that it varies in brightness, and we were confident that there are patchy cloud layers that rotate in and out of view and evolve over time,” explained Allison McCarthy, doctoral student at Boston University and lead author on a study published today in The Astrophysical Journal Letters. “We also thought there could be temperature variations, chemical reactions, and possibly some effects of auroral activity affecting the brightness, but we weren’t sure.”
To figure it out, the team needed Webb’s ability to measure very precise changes in brightness over a broad range of wavelengths.
This artist’s concept shows what the isolated planetary-mass object SIMP 0136 could look like based on recent observations from NASA’s James Webb Space Telescope and previous observations from Hubble, Spitzer, and numerous ground-based telescopes. Researchers used Webb’s NIRSpec (Near-Infrared Spectrograph) and MIRI (Mid-Infrared Instrument) to measure subtle changes in the brightness of infrared light as the object completed two 2.4-hour rotations. By analyzing the change in brightness of different wavelengths over time, they were able to detect variability in cloud cover at different depths, temperature variations in the upper atmosphere, and changes in carbon chemistry as different sides of the object rotated in and out of view. This illustration is based on Webb’s spectroscopic observations. Webb has not captured a direct image of the object.
NASA, ESA, CSA, and Joseph Olmsted (STScI)
Charting Thousands of Infrared Rainbows
Using NIRSpec (Near-Infrared Spectrograph), Webb captured thousands of individual 0.6- to 5.3-micron spectra — one every 1.8 seconds over more than three hours as the object completed one full rotation. This was immediately followed by an observation with MIRI (Mid-Infrared Instrument), which collected hundreds of spectroscopic measurements of 5- to 14-micron light — one every 19.2 seconds, over another rotation.
The result was hundreds of detailed light curves, each showing the change in brightness of a very precise wavelength (color) as different sides of the object rotated into view.
“To see the full spectrum of this object change over the course of minutes was incredible,” said principal investigator Johanna Vos, from Trinity College Dublin. “Until now, we only had a little slice of the near-infrared spectrum from Hubble, and a few brightness measurements from Spitzer.”
The team noticed almost immediately that there were several distinct light-curve shapes. At any given time, some wavelengths were growing brighter, while others were becoming dimmer or not changing much at all. A number of different factors must be affecting the brightness variations.
“Imagine watching Earth from far away. If you were to look at each color separately, you would see different patterns that tell you something about its surface and atmosphere, even if you couldn’t make out the individual features,” explained co-author Philip Muirhead, also from Boston University. “Blue would increase as oceans rotate into view. Changes in brown and green would tell you something about soil and vegetation.”
These light curves show the change in brightness of three different sets of wavelengths (colors) of near-infrared light coming from the isolated planetary-mass object SIMP 0136 as it rotated. The light was captured by Webb’s NIRSpec (Near-Infrared Spectrograph), which collected a total of 5,726 spectra — one every 1.8 seconds — over the course of about 3 hours on July 23, 2023. The variations in brightness are thought to be related to different atmospheric features — deep clouds composed of iron particles, higher clouds made of tiny grains of silicate minerals, and high-altitude hot and cold spots — rotating in and out of view. The diagram at the right illustrates the possible structure of SIMP 0136’s atmosphere, with the colored arrows representing the same wavelengths of light shown in the light curves. Thick arrows represent more (brighter) light; thin arrows represent less (dimmer) light.
NASA, ESA, CSA, and Joseph Olmsted (STScI)
Patchy Clouds, Hot Spots, and Carbon Chemistry
To figure out what could be causing the variability on SIMP 0136, the team used atmospheric models to show where in the atmosphere each wavelength of light was originating.
“Different wavelengths provide information about different depths in the atmosphere,” explained McCarthy. “We started to realize that the wavelengths that had the most similar light-curve shapes also probed the same depths, which reinforced this idea that they must be caused by the same mechanism.”
One group of wavelengths, for example, originates deep in the atmosphere where there could be patchy clouds made of iron particles. A second group comes from higher clouds thought to be made of tiny grains of silicate minerals. The variations in both of these light curves are related to patchiness of the cloud layers.
A third group of wavelengths originates at very high altitude, far above the clouds, and seems to track temperature. Bright “hot spots” could be related to auroras that were previously detected at radio wavelengths, or to upwelling of hot gas from deeper in the atmosphere.
Some of the light curves cannot be explained by either clouds or temperature, but instead show variations related to atmospheric carbon chemistry. There could be pockets of carbon monoxide and carbon dioxide rotating in and out of view, or chemical reactions causing the atmosphere to change over time.
“We haven’t really figured out the chemistry part of the puzzle yet,” said Vos. “But these results are really exciting because they are showing us that the abundances of molecules like methane and carbon dioxide could change from place to place and over time. If we are looking at an exoplanet and can get only one measurement, we need to consider that it might not be representative of the entire planet.”
This research was conducted as part of Webb’s General Observer Program 3548.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
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NASA Marks 110 Years Since Founding of Predecessor Organization
2 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
To celebrate the 110th anniversary of the organization that ultimately became NASA, the agency released a new collection of videos to highlight the history of the National Advisory Committee for Aeronautics (NACA) and the ways it transformed flight over four decades.
A new video collection highlights the history and significance of NASA’s predecessor organization.
Not long after the beginning of World War I, the United States Congress, concerned that America was lagging behind other countries, created a new committee to advance the nation’s flight technology development. On March 3, 1915, the NACA was founded “to supervise and direct the scientific study of the problems of flight, with a view to their practical solution.”
While the NACA began as a committee of only 12 leaders representing government, military, and industry, it rapidly expanded through World War II to develop America’s flight capabilities for defense and commercial uses. The organization became home to some of the nation’s best and brightest aeronautical engineers and world-class facilities, transforming into NASA at the dawn of the Space Age in 1958.
The new video collection highlights some of NACA’s striking historic photography and celebrates this pioneering organization with a brief history of its formation, expansion, and groundbreaking aeronautics research at four centers across the United States — the current homes of NASA’s Langley Research Center in Hampton Virginia,Ames Research Center in California’s Silicon Valley, Glenn Research Center in Cleveland, and Armstrong Flight Research Center in Edwards, California.
