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.
The tsunami of 2011 is well remembered in Japan. Some towns have recovered, while others struggle to return to a life that once was. The same is true for ecosystems. In a new study in PLOS ONE, Japanese researchers report how the sea life in different coastal regions of Japan struck by the tsunami have flourished or faltered. “We watched in real time an ecosystem recover from a large natural disaster,” said Reiji Masuda, who directs the Maizuru Fisheries Research Station at Kyoto University and led the study. “We could observe how species recovered and whether any invading species could thrive.”
What may be the largest exposed fault on Earth has been seen and documented by scientists for the first time. The ‘Banda Detachment’ fault in eastern Indonesia would explain a 7.2km (4.4 mile) deep abyss under the Banda Sea, which until now has remained a mystery to geologists. This area where the fault was found sits in the Ring of Fire, an area in the basin of the Pacific ocean where many volcanic eruptions and earthquakes occur. Sitting under the Banda Sea is the Weber Deep – the deepest point in our planet’s ocean that does not sit in a trench.
Seismologists in Japan have tracked, for the first time, a particular type of tiny vibration that wobbled through the Earth from the Atlantic seafloor. It was started by a “weather bomb”: the same low-pressure storm, off Greenland, which made UK headlines in late 2014.
Researchers who analyzed a history of tsunamis along the Pacific coast of Japan’s Tohoku region have learned that seawalls higher than 5 meters reduce damage and death, while coastal forests also play an important role in protecting the public.
When Greenland’s melting glaciers lose large chunks of ice, it’s a violent process. Last year, for instance, scientists documented that gigantic glacial earthquakes are triggered by the rolling and tumbling of billion-ton icebergs as they break away and hit the glaciers to which they once belonged – hard
Very little is known about ocean currents and generally about dynamics in the oceans. But radioactivity released into the Pacific by the Fukushima nuclear accident, which was quickly diluted to harmless levels, has allowed scientists to trace the ocean’s currents.
Scientists have developed the Time Reverse Imaging Method to take real-time data from the ocean sensors and use that information to recreate what the tsunami looked like when it was born. Once scientists have the tsunami source pinpointed, they can use it to make better predictions about what will happen once the waves reach shore. This new method is fast enough to compete with existing algorithms but much more accurate.
After an earthquake, less than 20% of the carbon in the water from plants and soil had been released through oxidation before being carried away by the river. Thus, they estimate that most of the 14 megatonnes of carbon that was probably released by the earthquake ended up being stored away.
Scientists think they see evidence of two huge tsunamis having once swept across the surface of Mars.
Some of the oldest continuous historical records from around the world show us how dramatically the climate has changed.
Japan’s lead in implementing sea defence improvements to guard against future disasters is an important reference point for other tsunami-prone nations, a study led by Plymouth University has suggested.