BrGDGTs data in 74 lake surface sediments from West China and in a short-core sediments from Lake YZH.xlsx

we investigated the distribution of brGDGTs in surface sediments of 65 lakes along a mean annual lake water temperature (MLWT) transect in West China and developed a regional MBT′5ME (methylation degree of 5-methylated brGDGTs) calibration for MLWT reconstruction. Meanwhile, a site-specific brGDGT calibration for Lake Yangzonghai (YZH) within the transect was generated, based on the relationship between the instrumental temperature record over the past 100 years and individual brGDGT abundances in a short sediment core of the lake. These two calibrations were applied to global lake surface sediments, as well as a long sediment core over Holocene in Lake YZH. The linear correlations between MBT′5ME and temperature are highly consistent among lakes from different regions, indicating the near-universal response of brGDGTs in global lakes to temperature (R2 = 0.89). However, MLWT inferred from the site-specific calibration shows a weak relationship with actual MLWT in global lakes (R2 = 0.20), indicating that the site-specific calibration might be only a result of overfitting rather than reflecting the response of brGDGT distribution to ambient temperature. Applications to a Holocene sediment core in Lake YZH reveal that regional MBT′5ME calibration was more suitable to reconstruct paleotemperature than the site-specific calibration.