Collaborative Research: Reconstructing millennial-scale trends and variability in western Pacific convection and hydrology from large lakes on Sulawesi, central Indonesia

这笔赠款是根据2009年《美国复苏和再投资法》(公法111-5)资助的。这笔赠款通过从苏拉威西岛的两个大湖中回收和分析新的沉积岩芯，支持印度尼西亚晚更新世和全新世对流和水文变异性的研究。这项研究建立在对这些湖泊的地震反射调查的基础上，这些调查记录了厚厚的沉积物以适合古气候研究的速度积累，并基于对现有短岩心的地球化学和同位素分析，这些分析表明过去约400年来区域对流和水文发生了重大变化。该小组将从这些湖泊中恢复新的沉积岩芯，并进行多重代理分析，以重建晚更新世和全新世期间的对流和水文变异性。这项工作将对印度尼西亚在晚更新世和全新世期间的对流和水文历史、ITCZ的变化以及热带太平洋纬向梯度的长期变化提供重要的新见解。智力价值：研究在两个关键领域：1)过去气候变化期间耦合气候系统的区域响应，如ITCZ和ENSO；2)过去气候突变的区域影响。印度尼西亚降水和水文的年际变化与ENSO的变化有关。了解ENSO等自然变化模式的长期变化在气候突变中的作用是一个关键问题，但现有记录在西太平洋水文学对气候突变的反应方面存在很大分歧。这些湖泊的气候记录将提供基本的重要数据，以评估热带西太平洋对流和水文学百年至千年尺度的趋势和变异性，以及热带太平洋平均状态、区域季风和过去气候变化期间ITCZ的强度和位置之间的相互作用。更广泛的影响：拟议的研究活动将提供人口稠密、快速发展地区的气候变异性的新记录，在该地区，粮食生产与ENSO驱动的降雨量变化存在定量联系。Matano湖和Towuti湖已被提议作为大陆钻探的重要地点，以获得热带太平洋的长期古环境记录，我们的实地工作将从这些具有科学价值但研究不足的大湖向科学界提供新的沉积岩芯和地震反射数据。拟议的研究将通过本科生和研究生的参与促进跨学科培训和学习，努力扩大我们对一个重要区域气候变化的基本知识。该项目还将通过加强私人投资机构、印度尼西亚、加拿大科学家和机构以及工业界之间的智力和研究合作，以及通过支持布朗大学和明尼苏达大学的基础设施，来加强研究和教育的基础设施。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This grant supports research on late Pleistocene and Holocene convective and hydrologic variability in Indonesia through the recovery and analysis of new sediment cores from two large lakes on the island of Sulawesi. This research builds upon seismic reflection surveys of these lakes that document thick piles of sediment accumulating at rates ideal for paleoclimate studies, and upon geochemical and isotopic analyses of existing short cores that indicate substantial changes in regional convection and hydrology during the past ca. 400 years. This group will recover new sediment cores from these lakes, and conduct multiproxy analyses to reconstruct convective and hydrologic variability during the late Pleistocene and Holocene. This work will provide fundamentally important new insights into the history of Indonesian convection and hydrology, changes in the ITCZ, and long-term changes in tropical Pacific zonal gradients in during the late Pleistocene and Holocene.Intellectual Merits: The research is in two key areas: 1) The regional responses of coupled climate systems such as the ITCZ and ENSO during past climate changes, and 2) The regional impact of past abrupt changes in climate. Interannual variability in Indonesian rainfall and hydrology are linked to variations in ENSO. Understanding the role of long-term changes in natural modes of variability such as ENSO in abrupt climate change is a critical question, yet existing records disagree substantially on the response of western Pacific hydrology to abrupt climate changes. Records of climate from these lakes will provide fundamentally important data to evaluate centennial- to millennial-scale trends and variability in tropical western Pacific convection and hydrology, and interactions between the mean state of the tropical Pacific, the regional monsoons, and the strength and position of the ITCZ during past climate changes.Broader Impacts: The proposed research activities will provide a new record of climate variability from a densely inhabited, rapidly developing region where food production has been quantitatively linked to ENSO-driven rainfall variability. Lakes Matano and Towuti have been proposed as important sites for continental drilling to obtain long paleoenvironmental records from the tropical Pacific, and our fieldwork will provide new sediment cores and seismic reflection data to the scientific community from these scientifically valuable but understudied great lakes. The proposed research will promote interdisciplinary training and learning through involvement of undergraduate and graduate students in an effort to expand our fundamental knowledge of climate variability in an important region. The project will also enhance infrastructure for research and education by strengthening intellectual and research collaborations between the PIs, Indonesian, Canadian scientists and institutions, and industry, and through support of infrastructure at Brown University and the University of Minnesota.