What do we know about climate stability ? The system is complex : the atmosphere, oceans and ice caps each have a specific role and dynamics, and react at different speeds. These different compartments interact in a non-linear way, but they are also connected to other complex systems, such as the carbon cycle. And the whole can be disrupted by various external causes, such as changes in insolation, which also act on different spatial and temporal scales. Natural climate variability is therefore high, but remains poorly understood. It is therefore difficult to determine a state of equilibrium and to discern a long-term trend from a transient fluctuation. For the past 20 years, modellers, paleoclimatologists and oceanographers have been exploring the most rapid climatic oscillations, the threshold phenomena that trigger the most abrupt transitions, in order to detect the conditions for genuine climate change.
Lecture