Findings suggest potential impacts on rainfall, storms, and regional climate patterns across the North Atlantic
A major Atlantic Ocean current system that helps regulate Earth's climate has been slowing for nearly two decades across a wide stretch of ocean, according to new research—potentially reshaping weather patterns across the globe.
The findings from the University of Miami Rosenstiel School of Marine, Atmospheric and Earth Science-led research team offer some of the clearest direct observational evidence yet that the Atlantic Meridional Overturning Circulation (AMOC) is weakening, helping scientists refine their understanding of ongoing climate changes and improve projections of future impacts.
"A weaker AMOC can shift weather patterns, potentially leading to more extreme storms, changes in rainfall, or colder winters in some regions," said Shane Elipot, a senior author of the study and physical oceanographer at the Rosenstiel School. "It can also influence sea-level rise along coastlines, affecting communities and infrastructure."
The researchers analyzed long-term data from four ocean monitoring arrays along the western boundary of the North Atlantic, spanning the tropics to higher latitudes. Using seafloor-anchored instruments that continuously record pressure, temperature, density, and currents, the team applied a consistent approach across all sites—using changes in bottom pressure to estimate deep ocean flow below about 1,000 meters. Comparing these measurements over time and across locations allowed them to identify long-term trends in the strength of the overturning circulation.
The observations across multiple latitudes showed a consistent decline in a key part of the AMOC along its western boundary, spanning from the subtropics to mid-latitudes (about 16.5°N to 42.5°N). The broad geographic extent of this trend suggests a basin-wide shift rather than a short-term fluctuation.
The AMOC is a critical part of Earth's climate system, helping regulate temperatures, weather patterns, and sea level, especially around the North Atlantic region. A slowdown could influence everything from European winters to hurricane activity and rainfall patterns.
The researchers say measurements along the western edge may also serve as an early warning signal, like a canary in a coal mine, offering an efficient way to track long-term changes in this critical climate-regulating system.
"This research helps scientists better predict how the climate may change in the coming decades—information that governments, businesses, and communities use to prepare for future environmental conditions," said Elipot .
The study, titled " Meridionally consistent decline in the observed western boundary contribution to the Atlantic Meridional Overturning Circulation ," was published in the April 8 issue of Science Advances.
The study was supported by grants from the U.S. National Science Foundation (OCE-2148723 and OCE-2334091) and UK Natural Environment Research Council grants (NE/Y003551/1 and NE/Y005589/1).
About the University of Miami and Rosenstiel School of Marine, Atmospheric and Earth Science
The University of Miami is a private research university and academic health system with a distinct geographic capacity to connect institutions, individuals, and ideas across the hemisphere and around the world. The University's vibrant academic community comprises 12 schools and colleges serving more than 19,000 undergraduate and graduate students in more than 180 majors and programs. Located within one of the most dynamic and multicultural cities in the world, the University is building new bridges across geographic, cultural, and intellectual borders, bringing a passion for scholarly excellence, a spirit of innovation, and a commitment to tackling the challenges facing our world. The University of Miami is a member of the prestigious Association of American Universities (AAU).
Founded in 1943, the Rosenstiel School of Marine, Atmospheric, and Earth Science is one of the world's premier research institutions in the continental United States. The School's basic and applied research programs seek to improve understanding and prediction of Earth's geological, oceanic, and atmospheric systems by focusing on four key pillars:
*Saving lives through better forecasting of extreme weather and seismic events.
*Feeding the world by developing sustainable wild fisheries and aquaculture programs.
*Unlocking ocean secrets through research on climate, weather, energy and medicine.
*Preserving marine species, including endangered sharks and other fish, as well as protecting and restoring threatened coral reefs. www.earth.miami.edu .
