摘要
To investigate the impacts of uncertain parameters on simulated Pacific Walker circulation （PWC）, a large number of perturbed parameter simulations are conducted using GAMIL2 （the Grid-point Atmospheric Model of IAP/LASG, version 2）, and three different PWC indices are selected.The results show that the influences of some parameters on PWC are dependent on the selected index - a finding supported by the inconsistent responses of different indexes to these parameters. Among the nine parameters, the RH threshold for deep convection （RHCRIT） is the most sensitive in simulating PWC. Increased RHCRIT weakens deep convective heating and stratiform cooling, and strengthens shallow convective heating. Further analysis reveals that uncertain parameters affect the simulated PWC through changing the diabatic heating and vertical motion.
沃克环流是全球气候系统中的重要分量之一。目前为止,针对气候模式本身,特别是湿物理过程中的云相关不确定性参数对于沃克环流模拟的作用如何研究较少。本研究对利用均匀抽样方法定量化地分析了IAP/LASG的大气环流模式GAMIL2中不确定参数对沃克环流模拟的影响。结果显示,基于不同物理量定义的强度指数对某些参数的响应不一致,存在明显的不确定性。9个所选参数中,深对流触发的相对湿度阈值对于模拟沃克环流强弱的作用最敏感。不确定性参数通过改变非绝热加热和垂直速度进一步影响沃克环流的模拟强度。
作者
XIE Feng
LI Li-Juan
WANG Bin
XUE Wei
XIE Feng;LI Li-Juan;WANG Bin;XUE Wei(State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics,Chinese Academy of Sciences;College of Earth Science, University of Chinese Academy of Sciences;Ministry of Education Key Laboratory for Earth System Modeling, Center of Earth System Science (CESS), Tsinghua University;Department of Computer Science and Technology, Tsinghua University)
基金
jointly funded by the National Key Research Project[grant number 2016YFB0200805]
the National Natural Science Foundation of China[grant number 41622503],[grant number 41475043],[grant number 41405073],and [grant number91530323]
Open Fund of Key Laboratory of Data Analysis and Applications,SOA[grant number LDAA-2014-03]
the National Key Basic Research Program of China[grant number2015CB954101]
