为探讨我国末次冰消期古气候时空演化特征,从北到南、从西到东分别选取8个和6个已发表的持续时间较长和分辨率相对较高的古气候记录,对比分析了我国末次冰消期气候演化(以Younger Dryas和Bφlling/Allerφd 事件为主)随纬度和海拔高度变化所表现出的趋势和规律.结果显示,末次冰消期的主要事件在我国基本均有显示.这些气候事件在北方高纬度地区比南方低纬度地区、东部低海拔地区比西部高海拔地区表现更强烈.推测末次冰消期北半球千年尺度气候变化信号来自高纬度显著温度波动.中低纬度地区这些气候事件波动减小可能与太阳辐射总量大、附近西太平洋和下垫面潜热缓冲大以及受东亚夏季风影响的植被盖度高等因素有关.这在探讨我国中低纬度末次冰消期气候变化时应该引起重视.%To explore temporal and spatial characteristics of palaeoclimate evolution in China during the last deglaciation,fourteen published records with higher resolution and longer time duration were selected for comparison, eight from north to south ( Hulun Lake in Inner Mongolia , Beijing , Midiwan in Shanxi, Sanmenxia in Henan , Hulu Cave , Dongge Cave , Huguangyan in Guangdong and the South China Sea) and six from west to east( Guliya , Chencuo in Xizang ,Qinghai Lake , Midiwan in Shanxi, Beijing and Sihailongwan in Jilin ) , respectively. The last deglacial climatic evolution trend with latitude or altitude changes was emphasized and analyzed by highlighting Younger Dryas and Bφlling/Allerφd events. Results show that the major climate events occurring during the last deglaciation could be observed in most places of China. As for the Northern Hemisphere , fluctuations of these climate events behaved more dramatically in high-latitudes than in low-latitudes , as well as in eastern low-altitudes than western high-altitudes in China. Accordingly , these millennial-timescale climatic shifts during the last deglaciation presumably originated from significant temperature fluctuations at northern high latitudes. The decreased fluctuations of these climatic events in middle to low latitudes were probably influenced by the increased insolation, greater buffering from the Western Pacific and rich latent heat of the underlying surface,as well as the well-developed vegetation cover. The above temporal and spatial characteristics of climatic evolution should arouse consideration when investigations are conducted on the climatic shifts in middle to low latitudes during the last deglaciation in the future.
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