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.