A new study finds evidence that the last time Earth was as warm as it is today, cold freshwater from a melting Greenland ice sheet circulated in the Atlantic Ocean as far south as Bermuda, elevating sea levels and altering the ocean’s climate and ecosystems. The research shows a large pulse of cold freshwater covered the North Atlantic for a brief period of time about 125,000 years ago.
We’re in the final month of meteorological winter, and Arctic sea ice extent continues to set record lows. The low amounts of ice, compared to average, in the Arctic region have been an ongoing concern since November, and hasn’t let up through the start of February. Ice extent in the Arctic region set daily record lows through most of January, leading to the lowest January extent in the 38-year satellite record, according to the National Snow and Ice Data Center (NSIDC).
Climate-driven disturbances are having profound impacts on coastal ecosystems, with many crucial habitat-forming species in sharp decline. However, among these degraded biomes, examples of resilience are emerging. Writing in BioScience, Jennifer O’Leary, a California Sea Grant Marine Biologist based at Polytechnic State University, and her colleagues describe these recoveries and highlight the possible implications for ecosystem-sparing management.
Coastal ecosystems and aquifers will be greatly affected by climate change, not only from rising temperatures and more volatile weather, including changes in precipitation patterns, but also from sea level rise. In the search for methods to analyze these effects, researchers at NJIT have identified powerful statistical tools that should help coastal scientists both measure and anticipate changes in conditions such as subsurface water temperature and salinity. Results from the study, funded by the National Oceanic and Atmospheric Administration, have been published in Scientific Reports, an online affiliate of Nature.
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.
Some beluga whales are adapting to climate change by changing their migratory habits, while other are not, a new study finds. Beluga whales spend the summer in the Beaufort and Chukchi seas, and winters in the warmer Bering Sea to the south. Some beluga whales are delaying their autumn southern migration by up to four weeks, according to a paper published in the journal Global Change Biology.
Changes in the way that ocean temperatures were measured in recent decades made it look like the oceans were getting cooler, but now independent data has confirmed that this so-called ‘hiatus’ in global warming never actually happened. The cause of the apparent hiatus in rising sea-surface temperatures was first identified in 2015 in a paper in the journal Science by scientists at the National Oceanic and Atmospheric Administration (NOAA). The paper proved controversial, but since its publication, several studies have backed up the idea that the hiatus didn’t in fact happen. The apparent hiatus has been linked to poor statistical methods, among other factors.
Intense future climate change could have a far different impact on the world than current models predict, suggests a thought-provoking new study just out in the journal Science Advances. If atmospheric carbon dioxide concentrations were to double in the future, it finds, a major ocean current — one that helps regulate climate and weather patterns all over the world — could collapse. And that could paint a very different picture of the future than what we’ve assumed so far. The Atlantic meridional overturning circulation, or AMOC, is often described as a large oceanic conveyor belt. It’s a system of water currents that transports warm water northward from the Atlantic toward the Arctic, contributing to the mild climate conditions found in places like Western Europe. In the Northern Atlantic, the northward flowing surface water eventually cools and sinks down toward the bottom of the ocean, and another current brings that cooler water back down south again. The whole process is part of a much larger system of overturning currents that circulates all over the world, from pole to pole.
A sophisticated new type of “tag” on whales that can record data every second for hours, days and weeks at a time provides a view of whale behavior, biology and travels never before possible, scientists from Oregon State University reported in a new study. This “Advanced Dive Behavior,” or ADB tag, has allowed researchers to expand their knowledge of whale ecology to areas deep beneath the sea, over thousands of miles of travel, and outline their interaction with the prey they depend upon for food.
The recent U.S. presidential election loomed large last week at the world’s largest annual gathering of Earth and space scientists, the American Geophysical Union’s (AGU) Fall Meeting in San Francisco, Calif. When Eos asked some of the more than 20,000 scientists at the meeting what they thought the election’s outcome means for the Earth and space sciences, we heard a wide range of responses, from dismissal of the election’s importance to deep concern.
Mother-of-pearl or nacre (pronounced nay-ker), the lustrous, tough-as-nails biomineral that lines some seashells, has been shown to be a faithful record of ancient ocean temperature. Writing online Thursday, Dec. 15, in the journal Earth and Planetary Science Letters, a team led by University of Wisconsin-Madison physics Professor Pupa Gilbert describes studies of the physical attributes of nacre in modern and fossil shells showing that the biomineral provides an accurate record of temperature as the material is formed, layer upon layer, in a mollusk.
At this week’s American Geophysical Union meeting, a team of researchers from the Woods Hole Oceanographic Institution (WHOI) presented their latest research findings on the long-range predictions of rainfall on land. Their method is based on ocean salinity rather than sea surface temperatures, which has been the standard for decades.