Extended Data Table 1. Mean annual temperature (MAT) estimation at Chuifeng Cave.

The 10 geographically closest meteorological weather stations included in publicly available WMO data are used to estimate current MAT at Chuifeng Cave. Correlation of online altitude estimation and WMO provided altitude is R²=0.99 (Pearson correlation).

WMO station ID	WMO station name	Longitude	Latitude	WMO altitude (m)	Estimated altitude (m)	First month	Last month	MAT	Altitude source used	Chuifeng Cave MAT
5920901	Ching His	106.42E	23.13N	740	743	February 1981	October 1990	19.5	WMO	22.8
5698505	Hekou	103.95E	22.5N	137	114	January 1961	December 1970	22.6	WMO	22.1
5791601	Tien-O	107.17E	25.0N	305	245	January 1981	October 1990	19.7	WMO	20.0
5904602	Ta Wan	109.42E	23.85N	76	81	January 1981	October 1990	20.8	WMO	20.0
5963201	Tung Hsing	107.97E	21.55N	13	10	February 1981	October 1990	23.0	WMO	22.0
5921100	Bose	106.6E	23.9N	na	154	January 1961	October 1990	22.5	Estimated altitude	22.2
5920901	Napo	105.95E	23.3N	na	1214	January 1981	October 1990	19.6	Estimated altitude	24.5
5900700	Guangnan	105.07E	24.07N	na	1257	January 1981	October 1990	17.6	Estimated altitude	22.8
5943100	Nanning	108.35E	22.82N	na	81	January 1922	November 1993	22.0	Estimated altitude	21.2
5902300	Hechi	108.05E	24.7N	na	204	January 1981	October 1990	21.2	Estimated altitude	21.1