Celsius:

0 is the phase transitiom temperature for water between solid and liquid under normal atmospheric pressure. 100 is the phase transition temperature between liquid and gas under normal atmospheric pressure.

It is important to note that high temperature increase will accelerate when feedback loops kick into action. Tim Lenton says that the right metaphor is not a chair falling over, as in, once we hit temperature X, then we doomed. If the chair falling over is used, then metaphorically it is falling through honey, the higher the temperature, the faster the fall and less time for finding solutions. Key takeaway: Never give up, always try to reduce emissions as they all have an impact on how much time we have.