A HOLOCENE CLIMATIC RECORD IN GUN NUUR, NORTHERN MONGOLIA

To retrieve regional records for depicting the global Holocene climatic changes, we successfully drilled 7.45 m lake core at Gun Nuur in the Northern Mongolian Plateau. Based on a reasonably constrained chronology and strikingly contrasted strata, we conducted a multi-proxy analysis of the core (e.g., magnetic parameters, pollen assemblages, total organic carbon and organic carbon isotope). The data show that the climate was still in the glacial mode (cold and dry) before 10,500 cal yr B.P. in the Northern Mongolian Plateau. The post-glacial warming occurred from 10,500 to 8,700 cal yr B.P. The climate was characterized by becoming warmer and dry from 8,700 to 6,500 cal yr B.P. After an about 1,500-year wet and cool climate between 6,500 and 5,000 cal yr BP., the second half of the elapsed portion of the Holocene has been characterized by wetter and cooler climate than the first half with three relatively warm and dry spells: 5000- 4000 cal yr B.P., 3500-3200 cal yr B.P. and 2500-1900 cal yr B.P. These major climatic fluctuations recorded in the lake Gun Nuur appear in-phase with those recovered in northern China. The magnetic records also show that climate changed abruptly at about 1600, 2900, 4500, 5900 and 8200 cal yr B.P., approximately echoing those abrupt events recorded in North Atlantic.