sentences:  These glacial advances loosely correlate to minima in the level of Lake Turkana around 4800, 4200, 3700, 3500, 3000, 2500, 2500, 2000 and 1600-1400 ya.As glaciers would have advanced during the dry phases when the temperature was cooler, it is not known why the correlation is not better, but it could be due to inaccuracies in dating.Since 1900 the glaciers have been steadily retreating and 7 out of 18 have disappeared.