Quantification of climate change for the last 20,000Â years from Wonderkrater, South Africa: Implications for the long-term dynamics of the Intertropical Convergence Zone

We do not propose that our findings invalidate the previous principal component analyses, but they do have the advantage of being based more clearly on the relationship between modern plant distributions and individual climatic variables. Results indicate that temperatures during both the warm and cold seasons were 6 ± 2 °C colder during the LGM and Younger Dryas, and that rainy season precipitation during the Last Glacial Maximum was ~ 50% of that during the mid-Holocene. Our results also imply that changes in precipitation at Wonderkrater generally track changes in Mozambique Channel sea-surface temperatures, with a steady increase following the Younger Dryas to a period of maximum water availability at Wonderkrater ~ 3-7 ka. These findings argue against a dominant role of a shifting Intertropical Convergence Zone in determining long-term environmental trends, and indicate that the northern and southern tropics experienced similar climatic trends during the last 20 kyr.