A 3000-year isotopic record from a stalagmite in Cold Air Cave, Makapansgat Valley, Northern Province

Detailed, high-resolution palaeoclimatic records are essential for understa nding process and variability of late Holocene climate change, yet suitable proxies for the largely arid southern African region are rare. Under certa in conditions, cave speleothems can provide high-resolution records that se nsitively reflect local climate variables and provide clues to the regional response of larger-scale climatic features. Here we report(18)O/O-16 and C -13/C-12 ratios from a well-dated, continuous, aragonitic stalagmite from C old Air Cave in the Makapansgat Valley, Northern Province, South Africa. Ca rbon and oxygen isotope records are broadly in phase although amplitude of carbon isotope shifts is not large by carbon isotope standards. The data su ggest that C-4 grasses were more abundant in wetter, warmer conditions and somewhat suppressed in drier, cooler conditions. Amplitude of oxygen isotop e shifts is high and suggests a positive relationship with temperature, unl ike the Cango Cave stalagmite. An extended period of oxygen isotope depleti on, beginning at about no 1400 and culminating in a marked depression at ab out AD 1700, is interpreted as the regional manifestation of the Little Ice Age.