Paleoceanographic Variability in the Atlantic Region

The Atlantic Ocean has undergone profound climatic and circulation changes over glacial–interglacial cycles and on millennial to centennial timescales. Variations in the Atlantic Meridional Overturning Circulation and the strength and position of subtropical and subpolar gyres have influenced heat transport between low and high latitudes, modulated sea-surface temperatures and salinity patterns, and driven shifts in atmospheric circulation such as the westerlies and the Intertropical Convergence Zone. Marine proxy records—ranging from planktonic foraminiferal assemblages and isotopic ratios in sediment cores to elemental geochemistry and radiocarbon dating—reveal synchronous and asynchronous responses across the North and South Atlantic basins. These changes have in turn been linked to terrestrial hydroclimate variability in Europe, Africa and the Americas, underscoring the basin’s role in global climate teleconnections and informing projections of future ocean–atmosphere interactions.

Research from Nature Portfolio

Recent studies have revealed complex reorganisations of Atlantic circulation beyond traditional indices. One investigation of early Little Ice Age climate demonstrates that atmospheric ridging over northern Europe split the westerly flow, driven in part by reduced Arctic sea-ice cover, offering an analogue for twenty-first-century hydroclimatic shifts under declining ice. High-resolution sea-surface temperature and salinity reconstructions in the Gulf of Mexico have uncovered centennial-scale variability in North Atlantic surface currents that tightly correlates with widespread precipitation anomalies in adjacent continents, particularly during the Little Ice Age. Another study of sedimentary radiocarbon offsets emphasises the influence of transient hydrodynamic processes—such as Atlantic–Mediterranean exchange and bottom-current gradients—on the age structure of organic carbon in marine sediments, flagging the need for careful interpretation of down-core proxies of past circulation.

Paleoceanographic Variability in the Atlantic Region publication trend

The graph below shows the total number of articles in paleoceanographic variability in the atlantic region across all publications each year (not limited to Nature Index journals).

Technical terms

Subtropical gyre: Large-scale wind-driven circulation in mid-latitude oceans transporting warm water poleward.

Subpolar gyre: Circulation system in high latitudes, including the Labrador and Irminger Seas, influencing deep water formation.

Atlantic Meridional Overturning Circulation (AMOC): System of surface and deep currents transporting heat northward and returning waters southward.

Intertropical Convergence Zone (ITCZ): Equatorial band of low pressure and convective rainfall whose shifts affect hemispheric rainfall patterns.

Planktonic foraminifera: Microscopic marine organisms whose shell chemistry records past sea-surface conditions.

Radiocarbon dating: Dating method based on decay of carbon-14 in organic remains, used to establish sediment chronology.

Proxy record: Indirect measure of past environmental conditions derived from chemical, biological or physical markers.

References

1. Asynchronous Poleward Migration of the Atlantic Subtropical Gyres Over the Past 22,000 years. Geophysical Research Letters (2025).
2. Split westerlies over Europe in the early Little Ice Age. Nature Communications (2022).
3. An abrupt weakening of the subpolar gyre as trigger of Little Ice Age-type episodes. Climate Dynamics (2016).
4. Hemispherically asymmetric trade wind changes as signatures of past ITCZ shifts. Quaternary Science Reviews (2018).
5. Pronounced centennial-scale Atlantic Ocean climate variability correlated with Western Hemisphere hydroclimate. Nature Communications (2018).
6. Transient hydrodynamic effects influence organic carbon signatures in marine sediments. Nature Communications (2018).