Two million year history of the Indian Monsoon

超过30亿人生活在受亚洲季风影响的地区，亚洲季风的降雨提供了至关重要的水资源，同时也通过洪水对人类生命构成了威胁。尽管季风对许多人来说很重要，但很难预测和模拟季风，这使得它在不断变化的全球气候中的未来发展不确定。为了帮助改进模型和预测，除了仪器记录之外，还需要季风变化的历史记录。东亚季风的许多记录来自中国和南中国海，而印度季风的过去变化主要是从阿拉伯海的季风强度记录中获得的。在这里，我们建议利用IODP船JOIDES RESOLUTION在安达曼海获得的独特的长沉积岩芯来研究印度次大陆和海洋上空印度季风降水的过去变化。我们的多代理方法将揭示过去200万年来大陆风化、径流和轨道时间尺度上的直接降水的变化，填补了我们过去对印度季风理解的一个根本空白。更详细的研究将审查最后一次冰川和冰川消融的千年时间尺度的变化，而单一有孔虫贝壳地球化学的新应用将使人们能够在选定的时间间隔内调查年际和季节时间尺度的变化。

Over 3 billion people live in the area influenced by the Asian monsoon, the rains of which provide vital water resources while posing a risk to human life through flooding. Despite the importance to so many the monsoon is difficult to predict and model, making its future development in a changing global climate uncertain. To help improve models and predictions, histories of monsoon variability beyond the instrumental record are required. Many records of the East Asian monsoon have been generated from China and the South China Sea while past variability of the Indian Monsoon is mostly known from records of monsoon wind strength over the Arabian Sea. Here we propose to use the unique long sediment core obtained by the IODP vessel JOIDES Resolution in the Andaman Sea to examine the past variability of Indian Monsoon precipitation on the Indian sub-continent and directly over the ocean. Our multi-proxy approach will reveal changes in continental weathering, runoff and direct precipitation on orbital timescales for the last 2 million years filling a fundamental gap in our understanding of the Indian Monsoon in the past. More detailed studies will examine variations on millennial timescales for the last glacial and deglaciation, and the novel application of single foraminifera shell geochemistry will allow variability on inter-annual and seasonal timescales to be investigated for selected intervals.