摘要
上新世早—中期是巴拿马海道关闭及印度尼西亚海道收缩的关键时期。目前,针对这两个海道关闭的气候效应已有不少研究,但多数研究关注巴拿马海道、洋流变化及其与北半球高纬冰盖发育的联系,缺乏两大热带海道关闭/收缩对东亚气候影响及机理的研究。我们基于挪威地球系统模型(NorESM-L)探讨了印尼海道收缩及巴拿马海道的浅关闭对东亚气候的影响。结果表明,热带海道的关闭/收缩加强了北太平洋的经向梯度,进一步导致夏季近地表气温在东亚北部降低,东亚南部升高;降水在长江流域至中国东海一线显著增加,但在东亚南部至西南部显著减少。冬季,近地表气温在东亚大陆地区升高,降水减少。上述变化主要由印尼海道的收缩导致,除冬季温度外,巴拿马海道浅关闭对东亚气候的影响较弱。此外,结合定性的记录-模拟对比,我们进一步揭示出热带海道的关闭/收缩可在一定程度上影响东亚气候在中上新世的转型,但不是主要驱动力。
The closure or constriction of tropical seaways during the early to mid-Pliocene(4.2-3 Ma)are highly relevant to paleoclimate due to their roles in modulating the global heat and moisture transport;however,their potential impacts on the East Asian(EA)climate and the underlying mechanism are unclear.Here,based on a set of sensitivity experiments using the NorESM-L AOGCM model,we systematically analyzed the influence of the Indonesian throughflow constriction and shallow central American seaway(CAS)closure on the EA climate.Our results reveal that the closure of tropical seaways leads to ocean surface warming in tropical regions and cooling in the mid-to-high-latitude North Pacific.The resulting sea surface temperature changes produce contrasting thermal effects in the northern(cooling)and southern China(warming),which leads to more precipitation along the mid-to-east elongated region of East Asia in summer,but causes warmer,drier condition in China in winter.This climate effect mainly results from the constriction of the Indonesian throughflow,with minimal impact from the shallow CAS closure.Combined with qualitative model-data comparison,our results further reveal that the closure/constriction of shallow tropical seaways can act to some extent on the EA climate transition during the Early to Mid-Pliocene but is not the major driver for this transition.
作者
谭宁
张仲石
郭正堂
王会军
TAN Ning;ZHANG Zhongshi;GUO Zhengtang;WANG Huijun(Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Institute of Earth Sciences,Chinese Academy of Sciences,Beijing 100029,China;China University of Geosciences(Wuhan),Wuhan 430074,China;Union Centre of Extreme Weather,Climate and Hydrogeological Hazards,China Meteorological Administration-China University of Geosciences(Wuhan),Wuhan 430074,China;Nansen-Zhu International Research Center,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China;CAS Center for Excellence in Life and Paleoenvironment,Beijing 100044,China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Key Laboratory of Meteorological Disaster,Ministry of Education,Nanjing University of Information Science and Technology,Nanjing 210044,China;Climate Change Research Center,Chinese Academy of Sciences,Beijing 100029,China)
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2022年第5期310-321,共12页
Earth Science Frontiers
基金
国家自然科学基金项目(41888101,41690114)
中国科学院专项(XDB26000000,XDA13010106)
国家自然科学基金项目(41907371)。
关键词
上新世
热带海道
东亚气候
太平洋海表温度
Pliocene
tropical seaways
East Asian climate
Pacific surface temperature
