Co-evolutions of temperature and monsoonal precipitation patterns from the latest Pleistocene to the mid-Holocene in Japan: Carbonate clumped isotope record of a stalagmite

Abstract Quantitative paleotemperature reconstruction is a challenging and important issue in paleoenvironmental studies, for which carbonate clumped isotope (Δ47) thermometry is a promising approach. Here we analyzed Δ47 values from 66 layers of OT02 stalagmite from Ohtaki Cave in central Japan, covering two separate time intervals (2.6–8.8 and 34.8–63.5 ka) to reconstruct terrestrial temperature and meteoric δ18O records. The average Δ47 temperature of the Holocene portion of this stalagmite was 16.3°C ± 5.6°C and the average of the latest Pleistocene portion was 9.7°C ± 4.6°C. Δ47 thermometry also revealed that the coldest intervals (5°C–10°C) correspond to the Heinrich stadials HSs4–6, and the warmest interval (up to 19.9°C ± 6.0°C) in middle Holocene (approximately 6–5 ka) accompanied by the Hypsithermal climate optimum. We also reconstructed past meteoric δ18O by subtracting the temperature effect from stalagmite δ18O. Average meteoric δ18O was − 8.22‰ ± 0.99‰ VSMOW in the Holocene and − 8.81‰ ± 0.84‰ in the latest Pleistocene. Over centennial timescales, meteoric δ18O was lower during colder periods, such as Heinrich stadials and the cooling event around 7 ka, and higher in warmer periods, such as Hypsithermal warming. These relations indicated synchronicities of terrestrial paleotemperature and paleoprecipitation in our study region. A temperature dependency of total 18O fractionation from sea water to precipitation is a likely reason for the negative correlation between temperature and meteoric δ18O. Additionally, East Asian summer monsoon (EASM) brought larger rainfall of high δ18O during the warm periods, whereas larger snow/rainfall of low δ18O brought from East Asian winter monsoon (EAWM) in colder periods. δ18O of OT02 had thus reflected changes in terrestrial temperature and meteoric δ18O, which are both strongly related to EASM and EAWM conflicting in a centennial timescale.