A wetter climate in the desert of northern Sudan 9900-7600 years ago

Early Holocene semi-aquatic and freshwater gastropod shells embedded in lake silts and clays occur in shallow depressions near Wadi Mansurab, ~15 km west of the lower White Nile in presently arid north-central Sudan. Ten new AMS radiocarbon ages obtained on shells from two of the clay pans accord with the four conventional radiocarbon ages from these sites published nearly forty years ago and show that the climate was significantly wetter in this part of the SE Sahara between 9.9 ka and 7.6 ka, with a concentration of ages (11 out of 14) within the six hundred year interval 9.0-8.4 ka. These ages are similar to the ages of the Mesolithic barbed bone harpoon sites of Tagra and Shabona, east of the lower White Nile, as well as the age of a recently mapped 450 km2 lake that was fed by an overflow channel from the main Nile in presently arid northern Sudan between 9.5 ka and 7.5 ka. Our results confirm that regionally wetter conditions away from the Nile coincided with times of high Nile flow in the early Holocene.Martin Williams and Geraldine E. Jacobse