Collaborative Research: High-Resolution, Low-Latitude Paleoclimatology Through Scientific Drilling of Lake Bosumtwi, Ghana

该奖项将从国际大陆钻探计划（ICDP）中增加120万美元的运营资金，用于从位于西非加纳热带森林低地的陨石撞击坑Bosumtwi湖获得多个湖芯进行古气候分析。研究人员的目标是在过去的100万年（Ma）中产生一个多代理和年际到千年尺度的气候变化记录。将对从这些岩心中获得的数据进行审查，以确定北大西洋、非洲和亚洲区域气候之间的潜在联系。该湖位于热带辐合带（ITCZ）的季节性通道之下，在水文上是封闭的，深缺氧的沃茨保留了每年的层状结构。该团队先前的研究已经产生了记录陨石坑撞击起源的地震剖面，而对先前回收的活塞沉积物岩心的分析产生了800年的环境数据记录。这些核心表明，非洲夏季风的强度下降，在新仙女木和海因里希1和2气候事件。这些新地点将钻穿多个温暖的间冰期，并将进一步促进古气候界对热带气候变化的更广泛理解。这项研究将与加纳科学家充分合作，以支持美国科学家与加纳同事之间的能力建设和技术转让。研究基金还将支持美国研究生，并为他们提供独特的研究经验。

This award is to augment $1.2M in operational funds from the International Continental Drilling Program (ICDP) to obtain multiple lake cores for paleoclimatic analyses from Lake Bosumtwi, a meteorite impact crater located in the tropical forest lowlands of Ghana, West Africa. The researchers aim to produce a multi-proxy and inter-annual to millennial scale record of climate change over the last ~1.0 million years (Ma). The data derived from the cores will be examined for potential linkages among climate from the North Atlantic, Africa, and the Asia regions. The lake is located beneath the seasonal passage of the Inter Tropical Convergence Zone (ITCZ) and is hydrologically closed with deep anoxic waters that preserve annual laminations. Previous research by the team has yielded seismic profiles that documented the impact origin of the crater while analyses of previously recovered piston sediment cores produced an 800-year record of environmental data. These cores have shown that the intensity of the African summer monsoon decreased during the Younger Dryas and during Heinrich 1 and 2 climatic events. The new sites will drill through multiple warm interglacial periods and will further the paleoclimate community's broader understand of climate variability from the Tropics. This research will be carried out in full collaboration with Ghanaian scientists to support capacity building and technology transfer between the US scientists and their Ghanaian colleagues. The research funds will also support American graduate students and provide them with a unique research experience.