Climate and Ice during the Last Interglacial

During the Last Interglacial (129-116 thousand years ago, ka) CO₂ and global temperature were both higher than they were before human industrialisation. By examining Last Interglacial climate, we thus gain insights into climate processes and feedbacks close to those expected by the end of the 21^st century. For example, if we understand Last Interglacial changes in the Greenland and Antarctic ice sheets, this helps constrain the likelihood of future Greenland and Antarctic ice sheet melt – and their subsequent contribution to global sea level rise.

The research of the BAS Paleoclimate Group follows an integrative approach. The combination of paleodata with climate modelling develops our understanding of the Last Interglacial climate and of why the climate and ice sheets changed during this time. We focus on the evolution of the climate and environment over the polar ice sheets and polar oceans. For this we use paleoclimatic archives, particularly polar ice and marine sediment cores. For example, whilst stable water isotopes and impurity content of ice cores can tell us about atmospheric temperature and circulation, stable isotope ratios of foraminifera in marine cores provide invaluable information about change in the oceans.

Alongside the interpretation of the measurements, a major challenge is to define robust chronologies for these different ice and marine archives. Recently we made significant progress on this challenge, when we produced the first data synthesis covering the Last Interglacial with updated and coherent ice-marine age models. As a result we have now identified the temporal and spatial imprint of Last Interglacial changes across high-latitudes regions (Figure). This new data synthesis allows models to be tested, helping us determine whether they can accurately predict environmental and climate changes in our warming world.

Temperature time slices across the Last Interglacial. Northern Hemisphere (top panel) and Southern Hemisphere (bottom panel) air and sea surface temperature anomalies. The size of the dots follows the temperature scale given in the box. For all panels, warming (cooling) compared with modern temperature is represented in red (blue). The temperature anomalies are relative to the World Ocean Atlas (WOA) 1998, 10 m-depth data for marine records and relative to present-day instrumental surface air temperature measurements for ice records. From Capron et al., Quaternary Science Reviews, 103, 116-133, 2014.

• to produce new last Interglacial data from ice, marine and terrestrial archives

• to better understand Last Interglacial changes in polar ice sheets, oceans, and sea ice

• to test the ocean-atmosphere-sea ice processes which led to Last Interglacial warming

• to further develop accurate and coherent chronologies for ice, marine and terrestrial records over the Last interglacial

This work is also supported by strong collaborations with:

Aline Govin (LSCE, France),

Joy S. Singarayer (University of Reading, UK)

Emma J. Stone (University of Bristol, UK),

Chronis Tzedakis (UCL, UK),

Paul J. Valdes (University of Bristol, UK),

Eric W. Wolff (University of Cambridge, UK),

This work is part funded by the UK-NERC grant iGLASS and the EU-Past4Future program.

1. Synchronous timing of past abrupt climate changes

   New research has revealed that climate changes associated with past episodes of abrupt warming in Greenland occurred synchronously across a region extending from the Arctic to the Southern Hemisphere subtropics. […]

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2. Prestigious award for BAS early career scientist

   Congratulations to Dr Emilie Capron who has been awarded the prestigious Early Career Scientist Award of the International Union of Geodesy and Geophysics (IUGG). Dr Capron is a palaeoclimatologist at British […]

   Read more of: Prestigious award for BAS early career scientist