Does the Last Interglacial indicate future climate instability?

A new UCL-led study shows that century-scale climate variability was enhanced during the Last Interglacial period (129-116 thousand years ago) compared to the current interglacial (the last 11,700 years). It was also punctuated by a series of arid events in southern Europe and cold water-mass expansions in the North Atlantic.

Current climate predictions suggest warm conditions under future carbon emission scenarios, so, as Professor Tzedakis argues, “The Last Interglacial is particularly relevant because it provides insights into climate processes during a period of excess warmth.”

During this period, with intense Arctic warming, surface air temperatures are estimated to have been 3-11°C above pre-industrial levels, comparable to current high-latitude scenarios by the end of this century. Global sea-level during the Last Interglacial is also estimated to have been around 6-9 m above the present, including 0.6-3.5 m derived from melting of the Greenland Ice Sheet

The study, by international researchers from twelve institutions, and published on 11 October in Nature Communications, used marine and terrestrial geological archives, coupled with climate model experiments, to create the most detailed timeline of ocean and atmosphere changes in the North Atlantic and southern Europe during the Last Interglacial period. It was funded by the Natural Environment Research Council (NERC) and the Australian Research Council (ARC),

““Although not a strict analogue for future anthropogenically-driven changes, the profile of the Last Interglacial that emerges is one of enhanced century-scale climate instability, with implications for ice-sheet and ocean dynamics,” explains Professor Tzedakis.  “Future research efforts should focus on constraining further the extent of melting and runoff from the Greenland ice-sheet and its effects on ocean circulation during the Last Interglacial.”

See

Enhanced climate instability in the North Atlantic and southern Europe during the Last Interglacial - P.C. Tzedakis, and 18 others