Lake-level history of Lake Tanganyika, East Africa, for the past 2500 years based on ostracode-inferred water-depth reconstruction

Abstract

Assemblages of ostracodes from sediment cores illuminate lake-level history at decadal to centennial timescales during the late Holocene at Lake Tanganyika, East Africa. The ostracode-based lake-level curves for several cores resemble both each other and the only previously published lake-level record of comparable resolution for Lake Tanganyika during this interval, successfully reconstructing known highstands, improving the chronology of known lowstands, and contributing new information on late Holocene lake-level variability at this important tropical African location. In agreement with other late Holocene records from East Africa, the surface level at Lake Tanganyika reflects predominantly arid conditions throughout this interval, interrupted by relatively brief episodes of higher precipitation and lake level. The most pronounced lowstand in the record occurs at ∼200–0 BC, with other significant lowstands dating to the intervals ∼200–500 AD, ∼700–850 AD, the Medieval Warm Period (MWP; ∼1050–1250 AD at Lake Tanganyika), and the latter part of the Little Ice Age (LIA; ∼1550–1850 AD). The most important wet intervals in the lake-level record are centered on ∼500 AD, ∼1500 AD, and ∼1870 AD. The highstands and lowstands reported here for Lake Tanganyika appear to be fairly coherent with other records of rainfall throughout East Africa during the MWP and the LIA. Prior to the MWP, paleoclimate records are apparently less coherent, although this may be a reflection of the resolution and abundance of recent paleoclimatic data available for this climatically complex region.