561 / 2024-09-18 12:58:25

Orbital and Millennial Variations in Wildfires Recorded in the East Siberian Arctic Shelf over the Last Glacial Cycle

Arctic； Wildfire； Black Carbon；High latitude； Global warming

Session 53 - Geological analogues for future warm ocean and climate

Wildfires and black carbon are key to understanding the global carbon cycle and climate change, especially in the rapidly warming Arctic. In this study, we analyze black carbon and stable carbon isotope of sedimentary core LV 90-8-1 on the East Siberian Arctic shelf to trace Arctic wildfire history since the last interglacial period. Our findings indicate that extreme warm/humid conditions during MIS 5e-c and MIS 1, as well as extreme cold/dry periods in MIS 4 and MIS 2, suppressed wildfire occurrence due to reduced fuel dryness and limited combustibles, respectively. In contrast, during the milder climatic conditions of MIS 5b and MIS 3, wildfires increased during warm stages and decreased during cold stages, correlating with Dansgaard-Oeschger cycles, largely driven by variations in fuel availability. The study underscores that frequent wildfires driven by climate may further intensify the Arctic warming through positive feedbacks.