IPCC AR6对地球气候系统中反馈机制的新认识  

New understandings of the feedback mechanisms in the earth climate system in IPCC AR6

作　　者：赵树云 孔铃涵 张华 王五科[1] 赵淑雨 马馨宇 吴丹阳 ZHAO Shuyun;KONG Linghan;ZHANG Hua;WANG Wuke;ZHAO Shuyu;MA Xinyu;WU Danyang(Department of Atmospheric Science,School of Environmental Studies,China University of Geosciences,Wuhan 430078,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China;Ningbo Meteorological Bureau,Ningbo 315012,China)

机构地区：[1]中国地质大学环境学院大气科学系,湖北武汉430078 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081 [3]宁波市气象局,浙江宁波315012

出　　处：《大气科学学报》2021年第6期805-817,共13页Transactions of Atmospheric Sciences

基　　金：国家自然科学基金资助项目(42005128);国家重点研发计划项目(2017YFA0603502)。

摘　　要：气候反馈反映了气候系统内部对外界干扰的适应过程,在很大程度上影响对未来气候变化的预估。本文对政府间气候变化专门委员会(IPCC)第六次评估报告(AR6)中有关气候反馈的内容进行了梳理。相比第五次评估报告(AR5),AR6对云反馈的认识有了较大提高,尤其是副热带海洋上空低云的反馈。AR6认为在高信度上云反馈参数为正值,即对气候变化起到一种放大效应。不过,云反馈的不确定范围在所有反馈机制中依然是最大的。除了普朗克反馈外,其他反馈机制(包括水汽、温度直减率、地表反照率、云、生物地球物理和非CO_(2)生物地球化学反馈)均在正值区间或零附近,总体上对气候变化起到放大效应。AR6对总的气候反馈的估计值为-1.16 W·m^(-2)·℃^(-1),5%~95%的置信区间为[-1.81,-0.51]W·m^(-2)·℃^(-1)。随着气候平均态的增暖,气候反馈参数很可能会更靠近正值。Climate feedback reflects the adaptation process of the climate system to external interference,and affects the prediction of future climate change to a great extent.This paper summarizes the content on climate feedback in the Sixth Assessment Report(AR6)of the Intergovernmental Panel on Climate Change(IPCC).In AR6,the understanding of cloud feedback has been improved greatly compared with that in AR5,especiallythe feedback of low clouds over the Subtropical Ocean.The net cloud feedback parameter is assessed to be positive with high confidence in AR6,which plays an amplification effect on climate change..However,the uncertainty range of cloud feedback is still the largest in all feedback mechanisms.Apart from Planck feedback,all the other feedbacks(water vapor,temperature lapse rate,land surface albedo,cloud,bio-geophysical and non-CO_(2) biogeochemical feedback)are positive or near zero,generally amplifying climate change.The estimate of general climate feedback parameter in AR6 is-1.16 W·m^(-2)·℃^(-1),with a 5%—95%confidenceinterval of[-1.81,-0.51]W·m^(-2)·℃^(-1).With global warming,the climate feedback parameters are likely to be closer to the positive value.

关 键 词：气候反馈 IPCC AR6 

分 类 号：P46[天文地球—大气科学及气象学]