P2C2: Characterizing East African Climate Through a Major Faunal Transition at 250 - 550 ka

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The great lakes region of tropical East Africa has been a magnet for human occupation and settlement since the origin of our species but currently is one of the most underdeveloped in the world. Meanwhile, the future climate trends of the region remain relatively unknown. This project will provide a perspective from the past on the future hydroclimate of the Lake Malawi basin, against which climate models can be compared for more reliable predictions of rainfall and drought and thus offer a much needed technical basis for water management in the region. The results will also provide important context to the evolution of our species and other mammals of eastern Africa during a crucial time period of its archaeological and evolutionary history. The project will support graduate and undergraduate students with mentoring activities designed to improve the likelihood of success in future careers which address national environmental and societal needs. The researchers will offer a workshop to secondary school educators that will bring hands-on experience with sediment cores. The researchers and educators will work together on curriculum development about modern day environmental and climate concerns by creating tested teacher-prep materials.Specifically, the research project will develop a high-resolution record of past temperature and rainfall in southern East Africa that spans a relatively well dated, recent, and significant evolutionary event that occurred sometime between 500 and 300 thousand years ago. The study will focus on the Lake Malawi basin in southern East Africa, where the Lake Malawi Drilling Project recovered the longest, high-resolution record of climate change yet to be recovered from the African continent. Researchers will analyze sediments in the Lake Malawi drill core at roughly a 1000-year interval for temperature and rainfall between 250 and 550 thousand years ago, as recorded by organic geochemical signals in the sediments (TEX86, leaf wax carbon and hydrogen isotopic composition). These analytical results will be compared to other such results from around the world, to seek commonality in the timing or direction of climate change. The team will also compare their results with climate model reconstructions of the region, to test the accuracy of various climate models that hindcast African climate, and to better comprehend what caused the observed climate behavior.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.