ABRUPT CLIMATE CHANGES: FROM THE PAST TO THE FUTURE - A REVIEW

Abstract

A review of climatic variability is given with a focus on abrupt changes during the last glacial. Evidence from palaeoclimatic archives suggests that these were most likley due to reorganisations of the atmosphere--ocean system. The mechanisms responsible for these changes are presented. Their implication for future climate changes is discussed in light of recent climate model simulations. Key words Abrupt climate change 7 Thermohaline circulation 7 Deglaciation 7 Paleoclimate 7 Younger Dryas Introduction Knowledge of past climate changes is important for two reasons. Firstly, the climate system exhibits natural variability on a range of time scales. Processes that govern this variability can only be understood if their temporal evolution is documented in the unperturbed climate of the past. Secondly, the range of possible climate states as a response to large perturbations has to be explored by reading the past records. Systematic measurements of the simplest parameters characte...