NOAA/WDS Paleoclimatology - Lake Malawi 700 Year Biogenic Silica Data

Biogenic silica profiles in varved sediments from northern Lake Malawi (Nyasa), East Africa, span the past 700 yr and reflect past primary productivity in the overlying waters. On a centennial scale this has been influenced by lake level and a consequent shift in the location of high diatom productivity within the lake basin. Primary production was higher during the Little Ice Age, an arid period from about A.D. 1570 to 1850, when lake level was about 120 m lower than during the previous three centuries or the past 150 yr. The data are biogenic silica (as % SiO2) versus age from six cores in the north basin of Lake Malawi, at the southern end of the East African Rift Valley.