Coupled temperature variations in the Huguangyan Maar Lake between high and low latitude

Model simulations and proxy-based reconstructions of the global temperature evolution from the Last Glacial Maximum to the present show significant discrepancies. To resolve this discrepancy is critical for understanding how climate evolves and also for evaluating current global warming. Here we report a branched GDGTs-based mean annual air temperature (MAAT) reconstruction from the sediments of Huguangyan Maar Lake in southeast China and validate it using historical documentary evidence and instrumental data. The reconstructed MAAT indicates distinct changes during the last deglaciation (Oldest Dryas, Bølling-Allerød, Younger Dryas). During the Holocene, temperatures gradually increased from the end of the Younger Dryas to ∼7.0 cal ka BP, followed by a stepped decrease until present. This terrestrial temperature record differs with model simulations and proxy sea surface temperature records of the Holocene, suggesting that our study reveals a regional climate pattern that was not adequately documented in previous research. The temperature variations in the Huguangyan Maar Lake are coupled with the forcings both from the high latitude (the Arctic) and low latitude (the Intertropical Convergence Zone). The decrease in ice volume and winter monsoon are the most prominent forcings that controlled the regional temperature evolution from the Last Glacial Maximum to the beginning of the middle Holocene, while the temperature variations during the middle and late Holocene were consistent with the southward shifts of the Intertropical Convergence Zone. •A high-resolution time-series brGDGT-based temperature reconstruction spanning last 20 ka was obtained from Huguangyan Lake•The MAAT indicates an early to mid-Holocene Thermal Maximum•Ice volume may be main driving force of the temperature evolution from Huguangyan Maar Lake.