Paleoclimate Dynamics of Interglacial Periods

Interglacial periods represent intervals of relatively warm climate between major ice ages, during which polar ice sheets retreat, sea levels rise and global ecosystems reorganise. These warm phases are paced primarily by variations in Earth’s orbital parameters, which modulate the distribution and intensity of solar insolation. Feedbacks involving greenhouse gases, vegetation cover, ice–albedo interactions and ocean circulation amplify orbital forcing, driving pronounced changes in temperature, precipitation patterns and ice‐sheet stability. The Last Interglacial, approximately 129 000–116 000 years ago, is a key analogue for future warming, having experienced sea levels several metres above present and enhanced Arctic summer warmth. Mid‐Holocene conditions, around 6 000 years ago, illustrate monsoon intensification and vegetation shifts under modest orbital forcing. Modern modelling and proxy syntheses now resolve millennial‐scale variability in ice‐ocean dynamics, monsoon systems and dryland extents, offering critical tests for climate models and insights into thresholds for ice‐sheet collapse, carbon‐cycle feedbacks and hydrological extremes.

Research from Nature Portfolio

Recent studies have illuminated the mechanisms by which subsurface ocean warming can destabilise ice shelves and contribute to sea‐level rise during warm intervals. Equilibrium simulations of last interglacial conditions indicate that reduced sea‐ice formation weakened deep‐ocean convection south of 60° S, raising temperatures by over 1 °C at 500 m depth on Antarctic continental shelves. These changes altered density gradients and wind fields, weakening the Antarctic Circumpolar Current and reinforcing warm inflow along the slope. Such processes are now recognised as critical for triggering ice‐mass loss from marine‐based sectors of the Antarctic ice sheet.

Paleoclimate Dynamics of Interglacial Periods publication trend

The graph below shows the total number of articles in paleoclimate dynamics of interglacial periods across all publications each year (not limited to Nature Index journals).

Technical terms

Interglacial Period: Warm interval between ice ages marked by reduced ice volume and higher sea levels.

Orbital Forcing: Changes in Earth’s orbit (eccentricity, tilt, precession) affecting solar insolation.

Ice–Albedo Feedback: Amplification of warming as melting ice reduces surface reflectivity, increasing absorption of solar radiation.

Marine Isotope Stage (MIS): Alternating warm and cold periods inferred from oxygen isotope ratios in marine sediments.

Aridity Index: Ratio of annual precipitation to potential evapotranspiration, indicating dryness of a region.

Deep‐Ocean Convection: Vertical mixing process that transports surface water to the deep ocean, influencing heat and carbon storage.

References

1. Last Interglacial subsurface warming on the Antarctic shelf triggered by reduced deep-ocean convection. Communications Earth & Environment (2024).
2. Contrasting latitudinal evolution of East Asian monsoonal precipitation during the Last Interglacial (130–120 ka). npj Climate and Atmospheric Science (2024).
3. The PMIP4 simulated dryland aridity changes during the Last Interglacial. Environmental Research Letters (2023).