第八届青年地学论坛

The Arctic ocean is one of the most sensitive areas to global warming, where sea ice cover has important impacts on solar radiation albedo, ocean primary productivity, ocean deep water formation and middle-low latitude climate change. Because of the temporal limitation of modern satellite observations, it is still lacking and urgently needed to construct long-term sea ice records to clarify the sea ice evolution and its environmental/climate change effects. Here, based on the core LV77-36-1 obtained from the first Sino-Russian joint Arctic scientific expedition in 2016 in the East Siberian Shelf (ESS), we reconstructed a sedimentary record of the Mid-Holocene (since ~8.2ka). We used the semi-quantitative sea ice reconstruction index (PIP₂₅) to reveal the history of sea ice evolution and sea-ice-air coupling process since the Mid-Holocene. The results show the sea ice evolution pattern in this region is consistent with those in other Arctic areas. The reduced sea ice covered in the Early Holocene warm period, and gradually changed to seasonal and perennial sea ice in Mid-to Late Holocene. In addition, our new high-resolution sea ice records show evident periodicities of ~1500yr and ~200yr, revealing the response of paleo-sea ice to Arctic Oscillation-like circulation pattern (AO-like). This study contributes to a better understanding of the evolution mechanism of Arctic sea ice under different climate change patterns, and has important implications for future models to predict climate change.

sea ice cover, AO-like, Mid-to Late Holocene, East Siberian shelf