The holocene prehistoric archeological record of msea, although still in early stages of investigation, suggests two broad periods with relatively coherent patterns: (1) an early holocene period. The early holocene ahp is one of the most thoroughly documented and well dated climate change events in the geologic record, and the number and diversity of paleoclimate records is remarkable.
The green sahara period (ca. 11,000 to 5000 yr b.p.) emerges at every site as the time interval with the most depleted δd p and the highest inferred rainfall rates . median rainfall rates during the green sahara, across all sites, were 640 mm year, but there is substantial spatiotemporal variability (1σ range, 250 to 1670 mm year; fig. 2b. During the early holocene epoch [11,000 to 5000 years before the present (yr b.p.)], the hyperarid sahara was transformed into a mesic landscape, with widespread grasslands,variabletreecover,largeper manent lakes, and extensive river drainage networks. evidence for this “green sahara” interval comes from paleolake deposits, pollen, and. These distributions suggest that, during the early holocene, the sahara was a savannah with riparian corridors linking north and south. patches of more arid terrain in mountain rainshadows may better explain the arid pollen found in north atlantic cores ( 8 ). The early to middle holocene humid period led to a greening of today’s arid saharo arabian desert belt. while this phase is well defined in north africa and the southern arabian peninsula.
These distributions suggest that, during the early holocene, the sahara was a savannah with riparian corridors linking north and south. patches of more arid terrain in mountain rainshadows may better explain the arid pollen found in north atlantic cores ( 8 ). The early to middle holocene humid period led to a greening of today’s arid saharo arabian desert belt. while this phase is well defined in north africa and the southern arabian peninsula. Vannière, b. et al., “ circum mediterranean fire activity and climate changes during the mid holocene environmental transition, (8500–2500 cal b.p.),” holocene 21 (2011), 57google scholar sachs , julian p. et al., “ southward movement of the pacific intertropical convergence zone ad 1400–1850 ,” natgeosc 2 ( 2009 ), 519–25 google. The expansion of monsoonal rains during the early holocene in the tropical latitudes permitted an extensive spread of moist savanna type vegetation over the sahara in north africa and the kalahari in south africa and in broad areas of brazil, india, and australia. most of these areas had been dry savanna or arid during the last glacial period.
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