The Shift of Southern Hemisphere Storminess under Anthropogenic Climate Change around Antarctica and its Impacts - (SACAI)

该提案的目的是调查南半球气旋的发展、其在目前气候条件下的变异性和极端情况、其在人为强迫条件下的可能转变及其对南极气候系统的影响。通过一个多模式集合，将估计本世纪末南半球气旋的发展，并将推导出不确定性的措施。这将包括对极端气旋的特别关注。气旋系统通过其相关的瞬变涡旋，造成流入南极洲的淡水，从而有助于将任何全球气候变化特征传递到南极洲。特别是，以下问题将得到解决：在人为气候变化下，SH气旋和风暴发展的特征是什么？从最先进的气候模式的角度来看，预期的变化范围是什么？在人为气候变化下，南大洋气旋活动的转移对南极气候系统造成了哪些影响？此外，还将进行调查，估计平流层变化对对流层和海洋环流的影响。因此，将使用最新的大气-海洋化学-气候模式ECHAM 5-MESSy-O进行模拟和分析。具体的模式配置使我们能够模拟南极大气和南大洋之间的反馈在不断变化的气候考虑平流层和对流层之间的垂直耦合，特别是地面气候对南极'臭氧洞'和增加温室气体（GHG）浓度的响应。

The proposal aims at the investigation of southern hemisphere cyclone development, its variability and extremes under present climate conditions, its possible shift under anthropogenic forcing conditions, and its impacts on the climatic system of Antarctica. By means of a multi-model ensemble the southern hemisphere cyclone development towards the end of this century will be estimated and measures of uncertainty will be deduced. This will include a special focus on extreme cyclones. Cyclone systems are, by their related transient eddies, responsible for freshwater fluxes into Antarctica, and thus contribute to the transmission of any global climate change signature towards Antarctica. Especially, the following questions will be addressed: What are the characteristics of SH cyclone and storm development under anthropogenic climate change and what is the range of expected changes from the perspective of state-of-the-art climate models? What are the impacts on the Antarctic climate system caused by a shift of the cyclonic activity over the Southern Ocean under anthropogenic climate change? Additionally, investigations will be carried out estimating the impact of stratospheric variability on tropospheric and ocean circulations. Therefore, simulations with the new state-of-the-art Atmosphere- Ocean Chemistry-Climate Model (AOCCM) ECHAM5-MESSy-O will be performed and analysed. The specific model configuration allows us to simulate the feedback between the Antarctic atmosphere and the Southern Ocean in a changing climate taking the vertical coupling between the stratosphere and the troposphere into account, in particular the response of surface climate to the Antarctic ‘ozone hole’ and increasing greenhouse gas (GHG) concentrations.