Latest news with #SurfaceWaterandOceanTopography
Daily Tribune
9 hours ago
- Science
- Daily Tribune
Scientists Crack Mystery Behind Planet-Shaking Nine-Day Tremors
A year after the Earth mysteriously trembled every 90 seconds for nine days straight—twice—scientists have finally traced the cause of the bizarre global seismic activity. The long-standing mystery has now been put to rest, thanks to a breakthrough study using cutting-edge satellite technology. In September 2023, seismometers around the world picked up rhythmic tremors occurring at regular 90-second intervals. The unexplained shaking lasted for nine days and reoccurred just a month later. These anomalies defied all known tectonic behavior and left scientists around the globe searching for answers. Now, in a study published in Nature Communications, researchers led by Thomas Monahan, a Schmidt AI in Science Fellow at the University of Oxford, have confirmed that the unusual seismic signals were caused by two colossal landslides in East Greenland's remote Dickson Fjord. These massive collapses triggered equally massive "mega-tsunamis," which in turn produced a phenomenon known as seiches—enormous standing waves that repeatedly sloshed within the fjord, creating rhythmic pulses that shook the Earth's crust. 'Previous studies in 2024 proposed the landslide-tsunami theory based on seismic patterns, but we lacked direct evidence to conclusively prove the link,' said Monahan. 'Our research now confirms it.' The key breakthrough came from data collected by NASA's Surface Water and Ocean Topography (SWOT) satellite, launched in December 2022. Using a unique radar altimetry technique, SWOT is capable of mapping water levels across 90% of Earth's surface in stunning detail. While traditional satellites missed the phenomenon due to infrequent measurements and complex fjord topography, SWOT's high-resolution twin-antenna system succeeded where others failed. The satellite captured the dynamic surface changes in the fjord as the seiches surged back and forth, providing the first-ever direct observations of the event and allowing researchers to match them precisely with the seismic data. 'This is a prime example of how new technology can transform our understanding of natural phenomena,' Monahan noted. The findings not only close a major scientific mystery but also open new pathways for monitoring remote and rugged environments using advanced satellite systems. As Earth's climate continues to shift, such insights could prove vital in understanding and anticipating the impacts of sudden geological events.
News18
2 days ago
- Climate
- News18
New Satellite Data Confirms Greenland's Mega-Tsunami That Shook Earth For 9 Days
A powerful tsunami caused by a massive rockslide in Greenland in 2023 shook the Earth for nine and new satellite data has now confirmed the full extent of its impact. The rare event, which took place in a remote sea valley, sent waves bouncing back and forth within steep cliffs, creating seismic tremors detected thousands of miles away. The international Surface Water and Ocean Topography (SWOT) satellite, operated by NASA and France's CNES, detected the movement of water in Dickson Fjord, located on Greenland's eastern coast.
New York Post
2 days ago
- Climate
- New York Post
‘Mega-tsunami' mystery solved — source of seismic activity that shook the world for 9 days revealed
This ought to cause a wave of panic. Back in 2023, scientists were perplexed by a mysterious seismic signal that shook the world every 90 seconds for nine days. Now, two years later, satellite footage has revealed the frightening source of these vibrations — giant mega-tsunamis sloshing around a Greenland fjord, per a 'Nature Communications' study. The massive walls of water — one of which measured 650 feet tall, or about half the height of the Empire State Building — were reportedly caused by the collapse of a massive mountainside that was triggered by a warming glacier, per the report. A total of 25 million cubic meters of rock and ice crashed into remote Dickson Fjord in East Greenland, the Daily Mail reported. This spawned colossal waves known as seiches that undulated back and forth in the water body for nine days like a giant bathtub or wave pool — hence the mysterious reverberations, Live Science reported. Study co-author Professor Thomas Adcock, who teaches engineering science at the University of Oxford, dubbed the findings 'an example of how the next generation of satellite data can resolve phenomena that has remained a mystery in the past.' í¥¤§í¨²´ çŸ³í¤°â¢ – 'That is an enormous wall of water bouncing back and forth,' study lead author Thomas Monahan, a graduate student in engineering science at the University of Oxford, told the Daily Mail. He estimated that the force exerted over the length of the fjord was 500 Giga Newtons, the 'equivalent to the amount of force produced by 14 Saturn V rocket ships launching at once.' While this seismic phenomenon was felt around the world, there were no observations of these tsunamis or landslides to confirm the theory. Even a Danish military vessel that entered the fjord three days into the first seismic event didn't observe the seiche rocking the planet. Thankfully, the Oxford researchers were able to fill in the blanks by analyzing data captured by the new Surface Water and Ocean Topography (SWOT) satellite, which, as the name suggests, tracks water on the surface of the ocean. Using a tool called Ka-band Radar Interferometer (KaRIn), the tech can map 90% of all water on the ocean's surface. Copernicus Sentinel-2 satellite image of the Dickson Fjord overlaid with sea-surface height measurements from the SWOT satellite. Thomas Monahan The traditional tsunami-measuring method, satellite altimetry, involves transmitting radar pulses onto the ocean's surface from orbit and then measuring the wave's height based on the time it takes for the pulse to return. Unfortunately, this technique is somewhat limited as it can't conduct accurate measurements in a confined space such as the fjord. By contrast, KaRin can pinpoint radar signals' returns with shocking precision using two massive antennae. Armed with this tech, Fjord forensics experts were able to observe cross-channel slopes moving in opposite directions between the fjord, confirming their presence. They then cross-referenced this with seismic observations, as well as weather and tidal readings, to recreate the waves and connect them to the reverberations. Study co-author Professor Thomas Adcock, who teaches engineering science at the University of Oxford, dubbed the findings 'an example of how the next generation of satellite data can resolve phenomena that has remained a mystery in the past.' 'We will be able to get new insights into ocean extremes such as tsunamis, storm surges, and freak waves,' he said. 'However, to get the most out of these data, we will need to innovate and use both machine learning and our knowledge of ocean physics to interpret our new results.' Monahan deemed the cutting-edge tech particularly crucial. 'This study shows how we can leverage the next generation of satellite Earth observation technologies to study these processes,' he said.
Yahoo
26-05-2025
- Science
- Yahoo
NASA satellite records unprecedented river waves in the United States
SAN DIEGO (FOX 5/KUSI) — NASA's U.S.-French Surface Water and Ocean Topography (SWOT) satellite, which was launched in 2022 from Vandenberg Space Force Base, has spotted large-scale river waves for the first time, the NASA Jet Propulsion Laboratory (JPL) in Southern California has announced. The river waves, which, unlike ocean waves, are temporary surges of water, stretched from 47 to 166 miles long as they traveled down rivers in Montana, Texas, and Georgia, the SWOT satellite recorded. James Webb Telescope captures new images of colliding Egg and Penguin galaxies: NASA The three large waves measured by the SWOT satellite from 2023 to 2024 were believed to be caused by extreme rainfall and a loosened ice jam, NASA reports, with the largest measuring over 30-feet-tall, creating potentially hazardous flood waves traveling down U.S. rivers. Ocean waves are primarily driven by wind and the gravitational pull of the moon and sun — tides – and move across the ocean until they crash to shore. According to NASA, river waves are temporary surges that can stretch tens to hundreds of miles, and are typically caused by rainfall or seasonal snowmelt. The waves can be beneficial, by shuttling nutrients and organisms down a river. But extreme river waves are usually triggered by a prolonged downpour or dam break and can cause floods. 'Out of this world' First-ever hip-hop song sent to Venus by NASA 'Ocean waves are well known from surfing and sailing, but rivers are the arteries of the planet. We want to understand their dynamics,' said Cedric David, a hydrologist at NASA's Jet Propulsion Laboratory in Southern California and a coauthor of a new study published May 14 in Geophysical Research Letters. Since 2022, the SWOT satellite has surveyed the height of nearly all of Earth's surface waters, both fresh and salty, using its sensitive Ka-band Radar Interferometer (KaRIn), which maps the elevation and width of water bodies by bouncing microwaves off the surface and timing how long the signal takes to return. NASA streams first-ever high-definition video from deep space Lead author Hana Thurman of Virginia Tech and team used SWOT data to search for river waves for her doctoral research. Thurman and team measured SWOT data that recorded the first wave on the Yellowstone River in Montana in April 2023. The satellite recorded the wave rise abruptly to 9.1 feet, and flow toward the Missouri River in North Dakota. It then divided into a 6.8-mile-long peak followed by a more drawn‐out tail. Through optical Sentinel-2 imagery of the area, Thurman was able to determine that the wave likely resulted from an ice jam breaking apart upstream and releasing pent-up water. The other two river waves were found to be caused by rainfall runoff. On Jan. 25, 2024, on the Colorado River south of Austin, Texas, a river wave over 30-feet-tall and and 166 miles long traveled around 3.5 feet per second for over 250 miles before discharging into Matagorda Bay, and was associated with the largest flood of the year on that section of river, according to NASA. NASA launches revolutionary PACE satellite to study Earth's oceans, changing climate The third wave originated on the Ocmulgee River near Macon, Georgia, in March 2024. The SWOT satellite measured it at over 20-feet-tall and extending more than 100 miles, traveling about a foot per second for more than 124 miles. 'We're learning more about the shape and speed of flow waves, and how they change along long stretches of river,' Thurman said. 'That could help us answer questions like, how fast could a flood get here and is infrastructure at risk?' The study is helping engineers and water managers measure river waves in ways never before possible, who have long relied on stream gauges. Also, knowing where and why river waves develop can help scientists track changing flood patterns around the world. 'Satellite data is complementary because it can help fill in the gaps,' said study supervisor George Allen, a hydrologist and remote sensing expert at Virginia Tech. Orbiting Earth multiple times each day, SWOT is expected to observe some 55% of large-scale floods at some stage in their life cycle. 'If we see something in the data, we can say something,' David said of SWOT's potential to flag dangerous floods in the making. 'For a long time, we've stood on the banks of our rivers, but we've never seen them like we are now.' Death Valley's temporary lake was measured by a NASA satellite. Here's how big it got NASA also used SWOT to measure how big the lake was that briefly formed in Death Valley in April 2024. The SWOT satellite was jointly developed by NASA and the French space agency CNES (Centre National d'Études Spatiales), with contributions from the Canadian Space Agency (CSA) and the UK Space Agency. NASA's Jet Propulsion Laboratory, managed for the agency by Caltech in Pasadena, California, leads the U.S. component of the project. Copyright 2025 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
Yahoo
09-05-2025
- Science
- Yahoo
Could A New Big Wave Come from Underwater Mountains?
Cortes Bank, the famed and elusive wave 100 miles off the coast of California, is an anomaly. The massive peaks that have seen XXL records and near-death experiences result from a seamount — an underwater mountain with a summit below the surface. Now, scientists in a NASA-backed project say they've found up to nearly 56,000 previously unmapped underwater mountains in the planet's oceans. Mapping the ocean floor for numerous economic and environmental repercussions. Ships need to know if there are any hazards in their way. Cable-laying and mining operations have to know what's going on down there, too. Scientists are also interested in what kind of geological formations and marine ecosystems exist in the depths. The Surface Water and Ocean Topography project, a collaboration between NASA and the French space agency Centre National d'Études Spatiales, used radar altimetry during a full year of satellite observations. The SWOT satellite covered about 90% of the planet every 21 days, and the seafloor map it created was published in Science in December 2024. 'The SWOT satellite was a huge jump in our ability to map the seafloor,' David Sandwell, a geophysicist at Scripps Institution of Oceanography in La Jolla, California, told NASA. How big of a jump was this research? The satellite measured small 'bumps' on the ocean's surface caused by the subtle gravitational pull of the large seamounts below, and researchers used that data to predict the location of the underwater masses. According to their pencils, the number of mapped seamounts skyrocketed from 44,000 to nearly 100,000. That's an estimated 56,000 previously hidden peaks, uncovered just like is the next Cortes Bank still out there? Could another mountain range intercept swells and cause a titanic wave to break on the ocean's surface? Unfortunately, it's too soon to tell. This data is preliminary, and the SWOT team is still calculating the depths of each feature the satellite pinpointed. This is part of an international effort to map the entire ocean bottom by 2030. Previous research could only detect seamounts over 3,300 feet (1 kilometer) in height. The SWOT team can find features half that height. For reference, the Cortes range rises an estimated 4,000 feet from the ocean floor, and its tallest point (Bishop Rock) comes alarmingly close to the surface. It's also in a prime position to cop the brunt of massive long-period Pacific Ocean power. It's entirely possible the newly mapped seamounts don't come close enough to the surface to cause swells to break. While the scientists crunch the numbers, best keep your eyes peeled.
