Fossils including sharks, sea reptiles and squid-like creatures dug up in Idaho reveal a marine ecosystem thriving relatively soon after Earth’s worst mass extinction, contradicting the long-held notion life was slow to recover from the calamity.
An international team of researchers has discovered why fresh water, melted from Antarctic ice sheets, is often detected below the surface of the ocean, rather than rising to the top above denser seawater.
Using decades of global climate data generated at a spatial resolution of about 25 kilometers squared, researchers were able to capture the formation of tropical cyclones, also referred to as hurricanes and typhoons, and the extreme waves that they generate. Those same models, when run at resolutions of about 100 kilometers, missed the tropical cyclones and the big waves up to 30 meters high.
For the 100 million people who live within 3 feet of sea level in East and Southeast Asia, the news that sea level in their region fluctuated wildly more than 6,000 years ago is important, according to research published by a team of ocean scientists and statisticians, including Rutgers professors Benjamin Horton and Robert Kopp and Rutgers Ph.D. student Erica Ashe. That’s because those fluctuations occurred without the assistance of human-influenced climate change.
Oceanographers commonly calculate large scale surface ocean circulation from satellite sea level information using a concept called “geostrophy”, which describes the relationship between oceanic surface flows and sea level gradient. Conversely, researchers rely on data from in-water current meters to measure smaller scale motion.
An ancient continent that was once sandwiched between India and Madagascar now lies scattered on the bottom of the Indian Ocean. The first clues to the continent’s existence came when some parts of the Indian Ocean were found to have stronger gravitational fields than others, indicating thicker crusts. One theory was that chunks of land had sunk and become attached to the ocean crust below.
The world’s primary economic source of iron ore, iron formations, are ancient sedimentary rocks that appear as solid as rocks can be. How did they get to be like that? According to researchers, it has to do with “green rust” that formed in the water and sank to the bottom of the ocean billions of years ago. In a study published in the journal Nature Geoscience, Itay Halevy and colleagues suggested that green rust was the foundation for today’s iron formations. It might be rare now, but green rust used to be highly abundant.
Looking at waves in the open sea with ‘electronic eyes’, so as to reconstruct it in 3D, scientists at Ca’ Foscari University of Venice and the Institute of Marine Sciences of the National Research Council (Ismar-Cnr) found that exceptionally high waves are more common than previously assumed by theoretical models.
On a recent stormy day, choppy waves crashed into the Scripps pier. Scenes like this are probably what most people picture when they think of waves. But surface waves aren’t the only kind. Scripps Institution of Oceanography researcher Peter Franks is interested in waves beneath the surface — internal waves. “These are gigantic waves,” he said. “If you could surf them, you’d surf for days — very, very, very slowly.” Franks studies how phytoplankton interact with internal waves. Phytoplankton are the tiny single-celled organisms that form the crucial base of the ocean’s food chain. Internal waves can play a role in accumulations of plankton such as red tides, which can sometimes be toxic. But Franks said piecing together exactly how that happens isn’t easy.
The cracking, bulging and shaking from the eruption of a mile-high volcano where two tectonic plates separate has been captured in more detail than ever before. A University of Washington study published this week shows how the volcano behaved during its spring 2015 eruption, revealing new clues about the behavior of volcanoes where two ocean plates are moving apart.
One of the most talked-about consequences of climate change is ocean acidification, which particularly threatens creatures that build shells. But there’s another big problem in the ocean’s chemistry that’s beginning to get out of control: oxygen. Even though they live underwater, fish breathe oxygen just like we do. Their gills pull dissolved oxygen out of the water. But the warmer the ocean’s water gets, the less dissolved oxygen it can hold. It’s basically the underwater equivalent of a human panting in the thin air on a mountaintop.
After successfully testing a long-range underwater communications system that worked under Arctic Ocean ice, an engineering team at Woods Hole Oceanographic Institution (WHOI) adapted it for a very different environment—the tropics—and for a different purpose—to provide warnings of impending tsunamis. While the Arctic sound-signaling system lets researchers communicate with robotic vehicles operating beneath sea ice, the tropical system, tested in 2016 off Indonesia, is designed to relay signals “from an undersea sensor network to shore, where they can be used to estimate the level of the potential tsunami,” said Lee Freitag, the WHOI engineer who led the project.