Figure 5

Temporal changes of TOC content (a) and the abundances of the total plankton (b), Synechococcus (c) and Isochrysis (d) in comparison with temporal changes of δ18O values of a stalagmite from Dongge Cave in Southern China34 (e) and the sunspot number37 (f).
The abundances of Synechococcus and Isochrysis were correlated either negatively (Periods I and III) or positively (Periods II). The three yellow bars refer to Bond events 0, 1 and 238. The green bar refers to a previously unrecognized cold period C1. Bond event 0 coincides with the Little Ice Age39. A green-to-red color scale is used to indicate Asian monsoon strength.