Dominic Royé
Researcher at the Galician Biological Mission – CSIC
The article is of very high quality. It has to be said that the authors use data previously published in other studies. The fact that climate change may end up being a partial or total catastrophe is supported by observation and climate projections. It is certain that our society must prepare and adapt to the worst-case scenario, even if it is not reached afterwards. Natural risk management is essential to reduce vulnerabilities, increase resilience, improve response and adaptation to climate change.
This work is consistent with what we know. We are not aware that there are changes in climate system processes that will be irreversible. One only needs to look at the so-called "planetary boundaries" to see the extent to which we have already exceeded many limits in different dimensions of the earth system. The earth system has a chaotic behaviour, therefore, possible tipping points can indeed lead to cascading effects with catastrophic consequences.
A call is being made for scientific exploration of possible catastrophic climate change. It does not imply that it will be. But I recall our recent heat death attribution study in which 35% can be attributed to climate change. So we could already talk about a catastrophe, at least partially, very slowly unlike other natural hazards, but it is already with us. Could it get worse? Yes, it can. It should also be noted that the acceleration of global temperature rise in combination with extreme events over the last decade shows that many natural processes are not linear. The increase is non-linear, i.e. more exponential.
In any case, there are still many unknowns about the limits of the climate system. However, it in no way detracts from the importance of exploring the worst-case scenario. It is better to be prepared than to risk irreparable damage and unforeseen consequences. The authors say that "caution is understandable, but it does not match the risks and potential damages posed by climate change".