In fact, deep ocean circulation slowed down to such an extent that the heavy, saline water mass below a depth of 2000 metres was not in contact with the surface for almost 3000 years. "During this time, so much bound carbon in the form of animal and algae remains trickled down from the more intermixed sea surface into the deep water layer that we were able to identify it as the major carbon reservoir that we have looked for so intensively," says Thomas Ronge. The data also showed that the already old age of the water masses was artificially increased...