Here is the Answer: Abrupt Climate Changes

Last posted question:

What is the difference between warming phases and cooling phases?

Here is the answer:

During cooling phases, the Earth tends to gradually cool down over a period of thousands of years. In contrast, warming phases happen over a few centuries! 

This discovery has put scientists infront of a difficult question: Slow climate changes are explainable with extraterrestrial forcing through the Milankovich cycles, but how do we explain those observed rapid climate changes?

When reconstructing climate, it is important to look not only at one component (eg the atmosphere) or one resource (eg ice cores), but many possible variables.
Thus, let’s have a look at a different climate record that highlights another component: coral reefs in the ocean:

Sea level fluctuation time series reconstructed from coral reef terraces, taken from Siddall et al. (2003)

When looking at past sea level stands we see almost identical fluctuation structures in the ocean compared to the fluctuations of temperature or greenhouse gases in the atmosphere.

Thus, mechanisms for changing climates may not only be found in the atmosphere, but also in the oceans.

And here is the big clue: Ocean Circulation is believed to be one possible mechanism that may trigger these otherwise unexplainable abrupt climate changes!