A one-million record of orbital-scale changes in temperature and precipitation from the Indo-Pacific Warm Pool

热带气候正在迅速变化--降雨事件变得更加强烈，干旱更加严重。 这些变化影响到数十亿依赖降雨维持生计的人的生活，并由于热带和全球气候之间的联系而对世界产生重要影响。预测未来降雨量和温度的变化需要长时间的记录来测试气候模型和理论。 在热带地区，特别是在热带西太平洋地区，这样的记录通常很少，现有的记录在过去气候变化的模式和幅度上存在很大分歧。 该项目的目标是从热带西太平洋（对全球气候过程特别重要的区域）开发温度、降雨量和植被的新记录，并调查其原因。 这项研究将使我们能够测试热带和全球气候变化的理论，从而提高对该地区未来气候的预测。 该项目将为美国研究生和本科生提供许多机会进行研究，并将开发新的气候变化课堂模块，用于普罗维登斯公立学校系统。这项研究将调查降雨，温度，和植被在过去的110万年在印度太平洋暖池（IPWP）通过分析最近-从位于印度尼西亚中部苏拉威西岛的Towuti湖回收的沉积物岩心。 通过对这些沉积物的有机地球化学分析，该项目将评估热带季节性日照、高纬度冰量、温度和大气温室气体浓度以及海平面变化对全球气候边界条件关键转变期间IPWP气候的影响。 该研究将重点关注80万年前中更新世期间的全球气候转变，当时冰川-间冰期变化主要从41 kyr过渡到100 kyr冰期周期，以及430，000，当100 kyr周期加剧时。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Tropical climate is changing rapidly – rainfall events are becoming more intense, and droughts more severe. These changes affect the affect the lives of billions of people who rely on rainfall for their livelihoods, and have important implications for the world due to connections between tropical and global climates. Predicting how rainfall and temperature will change in the future requires long records to test climate models and theory. Such records are generally scarce in the tropics, and particularly in the tropical western Pacific, where existing records disagree substantially on the pattern and magnitude of past changes in climate. The goal of this project is to develop new records of temperature, rainfall, and vegetation from the tropical western Pacific, a region that is especially important to global climate processes, and to investigate their causes. This research will enable us to test theories of tropical and global climate change, and thereby to improve the prediction of future climates in this region. The project will provide for many opportunities for US graduate and undergraduate students to conduct research and will develop new classroom modules on climate change to be used in the Providence Public School System.This research will investigate orbital-scale variations in rainfall, temperature, and vegetation during the past 1.1 million years in the Indo-Pacific Warm Pool (IPWP) through analysis of recently-recovered sediment drill cores from Lake Towuti, located on Sulawesi Island in central Indonesia. Through organic geochemical analyses of these sediments, the project will evaluate the impacts of changes in tropical seasonal insolation, high-latitude ice volume, temperature, and atmospheric greenhouse gas concentrations, and sea level on IPWP climate across critical transitions in global climate boundary conditions. The research will focus on global climate transitions during the Mid-Pleistocene, 800,000 years ago, when glacial-interglacial variability transitioned from predominantly 41-kyr to 100-kyr ice-age cycles, and 430,000, when the 100-kyr cycles intensified. The results are expected to contribute to understanding how tropical climates change in response to climate boundary conditions that differ from the present day.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.