An Encyclopaedia of Indian Archaeology v1.c12.s3.3

v1.c12.s3.3

Due to various uncertainties involved the estimates for each interglacial vary from 5000 to 25000 years. The Last Glacial began around 120000 and reached its peak around 20000 B.P. and ended by 10000 B.P.—the onset of the Holocene [9.6]. Broadly speaking, the climatic cycles in the two hemispheres were in phase. It has been estimated that in *c.* 18000 B.P. the land-based ice sheets in the n. hemisphere reached a thickness of 3 km. In the s. hemisphere there was a corresponding increase in the sea ice. The surface waters cooled to a global average of 2·3 C. Corresponding to these glacial maxima, the tropics registered an intensely arid phase reflected in the lake levels of Africa. The early Holocene interglacial warming of the n. latitudes is matched by an increase of precipitation by 150% (over the 1931-60 mean) between 24° N. and 8° S. in Africa.