currents

CLIMATEWIRE | The melting Greenland ice sheet is the single largest contributor to global sea-level rise — and some experts are warning it could soon cross the threshold into a slow but irreversible death spiral.A sweeping new scientific report, with contributions from more than 200 researchers, finds that continued warming could trigger not only the collapse of the Greenland ice sheet but a wide variety of tipping points in the Earth's climate system. Once crossed, those thresholds would have unstoppable…

So much on this planet depends on a simple matter of density. In the Atlantic Ocean, a conveyor belt of warm water heads north from the tropics, reaching the Arctic and chilling. That makes it denser, so it sinks and heads back south, finishing the loop. This system of currents, known as the Atlantic Meridional Overturning Circulation, or AMOC, moves 15 million cubic meters of water per second.In recent years, researchers have suggested that because of climate change, the AMOC current system could be slowing down and may…

The following essay is reprinted with permission from The Conversation, an online publication covering the latest research. If you’ve ever waded into the ocean for a swim and suddenly realized that the shore is getting farther away, not closer, you may have encountered a rip current. Common at beaches worldwide, these powerful currents flow from the shore toward the sea at speeds up to several feet per second. It’s important to know what rip currents are and how to look for them, because they are a leading cause of…

by Emma Shie Nuss, Audrey Casper, Christine M. Baker, Melissa Moulton and Walter Torres, The Conversation Pink dye exits the surf in a flash rip current (yellow arrow) during large-scale wave tank experiments. Credit: Christine Baker, CC BY-ND If you've ever waded into the ocean for a swim and suddenly realized that the shore is getting farther away, not closer, you may…

The new methodology accurately estimates the horizontal diffusion of water masses in different ocean regions. Credit: Instituto Español de Oceanografía Understanding Atlantic Ocean circulation is key for assessing the global ocean interconnections, in what is known as the "global conveyor belt." This is because the latitudinal ends of the Atlantic, bordering the polar regions, are cold-water formation regions that trigger the…

Deep-sea coral garden located in the Drake Passage seamount; image captured by a remotely operated vehicle (ROV). Credit: Laura F. Robinson Pioneering analysis of deep-sea corals has overturned the idea that ocean currents contributed to increasing global levels of carbon dioxide in the air over the past 11,000 years. The study,…

By U.S. Department of Energy June 22, 2023A spinning neutron disintegrates into a proton, electron, and antineutrino when a down quark in the neutron emits a W boson and converts into an up quark. The exchange of quanta of light (γ) among charged particles changes the strength of this transition. Credit: Image courtesy of Vincenzo Cirigliano, Institute for Nuclear TheoryNew Insights on the Interplay of Electromagnetism and the Weak Nuclear ForceNuclear theorists have discovered a major effect in neutron decay related to…

By focusing on the interaction between neurons, researchers have been able to uncover much about the way our brain's operate. A new study, though, has zoomed out a bit and found larger swirling patterns that seem to help the brain organize itself across regions.Studying the brain's electrical activity has led to some pretty impressive results in the last few years alone. We've seen new thinking about how the shape of the brain influences its function; methods to combat depression by magnetically stimulating certain parts…

In the crushing, cold depths of the oceans, something unimaginably huge flows inexorably, barely a few centimeters per second, along a path it has traveled for millennia. Dense, dark rivers of water toil ceaselessly around the world, making up around 40 percent of the total volume of the deep oceans. They are gigantic conveyor belts transporting heat, oxygen, carbon, and nutrients around the planet, and shaping climate and weather at a global, regional, and local scale.But something has changed, and these rivers appear to…

Credit: Steve Rintoul, Author provided Antarctica sets the stage for the world's greatest waterfall. The action takes place beneath the surface of the ocean. Here, trillions of tons of cold, dense, oxygen-rich water cascade off the continental shelf and sink to great depths. This Antarctic "bottom water" then spreads north along the sea floor in deep ocean currents, before slowly rising, thousands of kilometers away.…