Influence of cloud-radiation effects on the location of the intertropical convergence zone

热带辐合带（ITCZ）是地球气候系统的中心要素。它的位置决定了热带降雨和云的分布。ITCZ在地球历史上经历了巨大的纬向变化，并且很可能会在人为气候变化的反应中表现出这种变化。虽然ITCZ已经成为许多研究的主题，但云辐射效应的作用很少受到关注。受这一差距以及最近使用大气模型ECHAM 6进行的模拟的启发，该项目研究了云辐射效应如何以及通过何种机制影响ITCZ位置。以下两个问题得到解决。首先，云辐射效应对ITCZ位置的影响与风蒸发海面温度反馈相比有多强？第二，云辐射效应是放大还是抑制纬向ITCZ位移？这两个问题的答案是协调使用四个不同的大气模式与交互式海面温度。比较这四个模型提供了机会，以分离强大的非强大的模型行为，强大的模型行为的物理机制，并连接非强大的模型行为的云辐射效应的模型差异。该项目将在为期6个月的访问期间进行，访问巴黎的动力气象学研究所。这将使申请人能够与Sandrine Bony博士和Jean-Louis Dufresne博士密切合作，应用LMD大气模型，并将LMD模型与汉堡马克斯普朗克气象研究所的大气模型进行比较。

The intertropical convergence zone (ITCZ) is a central element of Earth's climate system. Its location determines the distribution of tropical rainfall and clouds. The ITCZ has experienced large meridional shifts in Earth's history, and will likely show such shifts in response to anthropogenic climate change. Although the ITCZ has been the subject of many studies, the role of cloud-radiative effects has received little attention. Motivated by this gap as well as recent simulations with the atmosphere model ECHAM6, the project investigates how and through which mechanisms cloud-radiative effects influence the ITCZ location. The two following questions are addressed. First, how strong is the influence of cloud-radiative effects on the ITCZ location in comparison to the wind-evaporation-sea-surface-temperature feedback? Second, do cloud-radiative effects amplify or damp meridional ITCZ shifts? These two questions are answered by the coordinated use of four different atmosphere models with interactive sea-surface temperatures. Comparing the four models provides the opportunity to separate robust from non-robust model behavior, to relate robust model behavior to physical mechanisms, and to connect non-robust model behavior to model differences in cloud-radiative effects. The project will be carried out during a 6-month visit to the Laboratoire de Meteorologie Dynamique in Paris. This will allow the applicant to closely collaborate with Dr. Sandrine Bony and Dr. Jean-Louis Dufresne, to apply the LMD atmosphere models, and to compare the LMD models to the atmosphere models of the Max Planck Institute for Meteorology, Hamburg.