Comparison of the Holocene and Eemian paleohydrological cycle: model-data synthesis of monsoon precipitation amplitudes in key regions

该项目的目的是通过将古代理重建与气候模型模拟相结合来比较全新世和伊米亚大气水文循环。由于伊米亚气候可能比全新世高出1至2摄氏度，可以预期会出现一个强化的水文循环。然而，古替代数据并没有明确指出这种更潮湿的条件，而气候模型的结果支持在更温暖的伊米亚气候下更强烈的季风系统。在拟议的研究中，来自非洲、印度和中国近海海洋沉积物的现有和新的季风降水古记录将与现有的陆地档案替代记录一起汇编成一个全面的数据集。将使用最先进的耦合大气海洋环流模式(AOGCM)进行气候模式模拟，以与古数据记录进行比较，并分析大气水文循环的空间和时间变化模式。我们将重点关注三个关键地区(几内亚湾、孟加拉湾和南中国海)，在这些地区，海洋古数据可以通过陆地植物类脂物质的同位素研究和通过盐度变化的河流径流来深入了解大陆古水文学。此外，在气候模型的帮助下，我们的目标是更好地区分和统计分析各自核心位置和各自河流集水区的海洋和陆地水文影响。

The aim of the project is to compare the Holocene and Eemian atmospheric hydrological cycle by combining paleo proxy reconstructions with climate model simulations. As the Eemian climate was probably by 1 to 2°C warmer than that of the Holocene, an intensified hydrological cycle can be expected. However, paleo proxy data do not clearly indicate such wetter conditions, whereas climate model results support more intense monsoon systems under warmer Eemian climate. In the proposed study existing and new paleorecords of monsoonal precipitation stemming from marine sediments off Africa, India, and China will be compiled into a comprehensive data set together with existing proxy records from terrestrial archives. Climate model simulations using a state-of-theart coupled atmosphere ocean general circulation model (AOGCM) will be used for comparison with the paleodata records and for the analysis of spatial as well as temporal variability patterns in the atmospheric hydrological cycle. We will focus on three key regions (Gulf of Guinea, Bay of Bengal and South China Sea), where marine paleodata allow insights into the continental paleohydrology by isotope studies on land plant lipid material and for river runoff via salinity variations. Furthermore we aim, with the help of the climate model, to better separate and statistically analyse marine and terrestrial hydrological effects at the respective core locations and in the catchment areas of the respective rivers.