Dendrochronological Paleoclimate Reconstruction for Monsoon Asia

亚洲季风的树木年代学古气候重建

基本信息

批准号：
12575022
负责人：
SWEDA Tatsuo
金额：
$ 6.02万
依托单位：
Ehime University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

With an objective of reconstructing paleoclimate over the past 500 years diagonally across Monsoon Asia, a series of field search for and subsequent increment core sampling from old trees was conducted at a total of 32 sites in Kamchatka Peninsular, Japan, Laos and the Nepal Himalayas, resulting in a total of some 1800 increment cores from some 900 individual trees. The longest core was obtained from Fokienia hodginsii of apparent age of over 1000 years located in Northern Laos.A series of analysis of ring-width variation in response to local climate for each sampling site and subsequent conversion of ring-width index using site specific transfer functions resulted in paleoclimate reconstruction of past 300 yrs for Eastern Nepal, 285 yrs for Western Nepal, 420 yrs for Central Kamchatka, 210 yrs for Southern Kamchatka and 240 yrs for Island of Shikoku, Japan. The 700-yrs reconstruction for Northern Laos is yet to come due to difficulty from limited number of samples and more or less obscure rings. Comparison of these local reconstructions revealed a regionally integrated trend of global warming appearing definitely and as early as two centuries ago in Kamchatka to show later and less definitely southward, ending up virtually no existent in the Himalayas. This regional trend of the past global warming is consistent with projected future trend of definite warming in higher latitudes with increasingly less warring in lower latitudes.

为了重建季风亚洲对角线过去500年的古气候，在堪察加半岛、日本、老挝和尼泊尔喜马拉雅山的总共32个地点进行了一系列实地搜寻和随后从古树中进行增量核心取样，大约 900 个单独的树总共产生了大约 1800 个增量核心。最长的岩心取自位于老挝北部的福建柏，其表观年龄超过1000年。对每个采样点的环宽随当地气候变化的变化进行了一系列分析，并随后使用位点特定转移对环宽指数进行了转换函数导致尼泊尔东部过去300年、尼泊尔西部285年、堪察加中部420年、尼泊尔210年的古气候重建堪察加半岛南部和日本四国岛 240 年。由于样本数量有限和或多或少模糊的环，老挝北部的 700 年重建工作尚未完成。对这些当地重建的比较揭示了全球变暖的区域综合趋势，早在两个世纪前就在堪察加半岛出现，后来又不太确定地向南移动，最终在喜马拉雅山几乎不存在。过去全球变暖的区域趋势与预计的未来趋势一致，即高纬度地区肯定变暖，而低纬度地区交战越来越少。