All articles tagged with #ocean currents
Scientists warn that the Atlantic Meridional Overturning Circulation (AMOC) may weaken or collapse sooner than expected, potentially disrupting European climate and economies. A 'cold blob' in the North Atlantic signals this shift, prompting European governments to treat the risk as a national security threat and invest in monitoring and adaptation.
The Atlantic Meridional Overturning Circulation (AMOC) is weakening as the climate warms, reducing a major heat-transport system that keeps Europe warm and helps regulate global weather. Projections suggest about a 50% weakening by 2100, with salinity changes in the South Atlantic identified as a key driver, though model predictions vary widely. A complete AMOC shutdown could trigger drastic shifts—stronger European temperature extremes, Sahel drought, and potentially a snowball-Earth-type cooling—with some studies hinting the tipping point could arrive as early as the 2040s. Geoengineering ideas like damming the Bering Strait exist but are controversial and uncertain. The article emphasizes urgency to cut greenhouse-gas emissions under the Paris Agreement to avert severe outcomes.
In 1992, a container spill released 28,800 bath toys into the Pacific. Seattle oceanographers leveraged sightings from beachcombers to validate the OSCUR model, turning the toys into a two-decade natural experiment that traced currents, revealed gyre pathways, and helped establish flotsametrics as a key method in modern oceanography.
A Greenland expedition highlights fear that the Atlantic Meridional Overturning Circulation (AMOC) is weakening as warming and freshwater inputs hinder deep-water formation, raising the risk of a rapid slowdown or collapse with far-reaching effects on Europe, the Americas, and global climate; researchers are racing to measure signals amid natural variability, while some propose drastic geoengineering options, though most emphasize reducing CO2 as the reliable solution.
A new Nature Geoscience study finds the Atlantic Meridional Overturning Circulation is weakening; if it collapses, Northern Europe could cool by about 5–15°C (9–27°F), but the global climate may warm overall as heat builds up in the ocean when the circulation slows. Greenland ice melt adds freshwater that further slows the current, and past weak periods tend to redistribute heat rather than reduce total planetary heat, suggesting a potential net increase in global warming as temperatures rise.
A multinational team aboard the RRS Sir David Attenborough sails to Greenland to study tidewater glaciers and how melting ice sheets could rewire the North Atlantic Subpolar Gyre, with autonomous sensors and AI helping improve climate models; the six-week SE Greenland fjord campaign aims to reveal glacier–ocean interactions that could affect UK rainfall, storms, reservoirs and North Atlantic fisheries.
A new climate reanalysis-backed study links a persistent cold patch southeast of Greenland to a weakening Atlantic Meridional Overturning Circulation (AMOC). While surface heat loss has declined since 1955, deep-water temperatures drop as much as 1,000 meters below the surface, suggesting less warm water entering the region. If AMOC continues to weaken or collapses, Europe could cool, tropical rainfall patterns could be disrupted, and sea levels near the US East Coast could rise; however, scientists caution that the debate over the cold blob and AMOC's status is not yet settled.
A large cold patch nicknamed the 'cold blob' south of Greenland is cooling the North Atlantic by about 2°F since 1900, suggesting the Atlantic Meridional Overturning Circulation (AMOC) is weakening due to warming and fresh water from melting ice; a significant slowdown or collapse could raise U.S. East Coast sea levels, bring colder European winters, and trigger droughts in Africa.
Scientists link a persistent cooling anomaly south of Greenland—the North Atlantic 'cold blob'—to a slowdown in the Atlantic Meridional Overturning Circulation (AMOC). A weaker AMOC could reduce the ocean's heat transport, shifting weather, storm tracks, and potentially accelerating sea-level rise along the U.S. East Coast, with the strongest impacts near Greenland, Iceland, and northern Europe.
Evidence cited by New Scientist shows the Atlantic Meridional Overturning Circulation is weakening, allowing cold Greenland waters to pool in the North Atlantic and form a 'cold blob' that can disrupt the jet stream and drive extreme weather; some models warn of a potential climate tipping point by around 2040, though scientists debate whether the slowdown is driven more by oceanic processes or atmospheric forces.
New study links the Atlantic's cooling 'cold blob' south of Greenland to a weakening Atlantic Meridional Overturning Circulation (AMOC), implying reduced heat transport and a sign of a climate tipping point. If AMOC collapses, Northern Hemisphere temperatures could drop dramatically (10–15°C in parts of the north), with heat and drought disruptions across Europe and rising sea levels along the US East Coast. Yet the exact rate of AMOC weakening is uncertain, and some researchers attribute the blob to surface heat loss rather than interior transport. The findings come as policy moves to remove deep-sea monitoring instruments could hamper tracking of this critical system.
A new study projects the Atlantic Meridional Overturning Circulation (AMOC) to weaken about 51% by 2100—roughly 60% more than standard models predict—after correcting biases in simulations. Such a weakening could raise U.S. Northeast sea levels, shift tropical rainfall belts, and usher colder European winters, with a growing risk of crossing a tipping point toward collapse. Observations indicate a 10–20% weakening since the mid-2000s, and while attribution to human-caused climate change remains uncertain for now, scenarios with strong CO2 cuts could limit the decline much more than high-emission futures.
A Science Advances study estimates the Atlantic Meridional Overturning Circulation (AMOC) could slow about 50% by 2100—a weakening stronger than some models predicted—potentially cooling northern Europe and altering rainfall in various regions. The researchers argue that including sea surface temperature and salinity improves forecasts, but experts caution there is substantial uncertainty in the magnitude and timing of the slowdown. While a catastrophic “collapse” is unlikely in the near term, the paper underscores a real risk of crossing a tipping point, prompting calls for nations to prepare for significant climate effects.
The lion’s mane jellyfish (Cyanea capillata) is the longest known animal, with a bell up to about 2.1 meters and tentacles that can extend over 36 meters, longer than any other animal on Earth, though it has almost no mass compared with a blue whale. It is brainless and boneless, made mostly of seawater (~94%), and drifts with currents while its thousands of tentacles form a wide hunting net; the nematocysts on its tentacles fire in under 700 nanoseconds. This long-tentacled strategy is energetically cheap in cold Arctic waters, though it reduces propulsion efficiency by up to 80–90%. The species’ blooms are studied as indicators of ocean health and warming, contrasting with the blue whale’s massiveness but highlighting a different kind of “largest”—reach versus weight.
New research shows the Southern Indian Ocean has become dramatically less salty over six decades, with salinity down about 30% due to wind-driven freshwater inflows from the Indo-Pacific pool. The resulting lighter, less dense water weakens deep ocean mixing, potentially disrupting the global thermohaline circulation and altering climate patterns beyond the region, with possible impacts on marine ecosystems.