Part 3: Tipping points

Overview of some tipping points and their implications. Source

What are tipping points?

The following picture shows an example of a tipping point. When the glass is in the center of the table, it is in a stable state. We can push the glass across the table and not much happens at the beginning. But as soon as the glass reaches the edge of the table, i.e. the tipping point, it will tip over if we push it a little further. After we push it over the edge, the state of the glass will quickly change without any other external influence until it hits the ground. At the floor, the glass is in a stable state again, but it might be shattered, so we might not like the new stable state. After the glass hits the floor, we may not be able to return it to its original state on the table, and even if we could (in the case it’s not shattered after the fall), we would need much more energy than we used to push it over the edge.

Cat pushing a glass over a tipping point (the edge of the table).

Climate tipping points work in a similar way. Once we cross them, our climate will change significantly. We should also be careful not to get too close to these tipping points, because if they are very close, natural fluctuations could push us over the edge.

Another reason I used this cat gif is because I think the cat perfectly illustrates our current behavior. In the original video, the owner tells the cat to stop pushing the glass. The cat looks at the owner and at first looks like it is listening, but then it pushes the glass over the edge anyway.
Similarly, scientists have been warning us about climate change and climate tipping points for decades. And although 195 countries have signed the Paris Agreement, almost none of them (if any) are doing what is necessary to stop climate change, and so we are pushing the climate toward many tipping points.

Climate tipping points

  1. Why is this system a tipping point?
  2. Where is this tipping point?
  3. What would happen if we crossed the tipping point?

List of climate tipping points articles:

The tipping points described above do not constitute an exhaustive list of potential tipping points. There are a number of other parts of the Earth system that have the potential to display tipping point behaviour including: Alpine glaciers, West African monsoon shift, Indian monsoon shift, El Niño Southern Oscillation, Arctic summer sea-ice, Arctic winter sea-ice and the East Antarctic Ice Sheet.

Crossing each of these tipping points would have different consequences, but what they all have in common is that it would certainly be bad for us.

Cascading Effects:

Global map of potential tipping cascades. The individual tipping elements are color- coded according to estimated thresholds in global average surface temperature (tipping points) (12, 34). Arrows show the potential interactions among the tipping elements based on expert elicitation that could generate cascades. Note that, although the risk for tipping (loss of) the East Antarctic Ice Sheet is proposed at >5 °C, some marine-based sectors in East Antarctica may be vulnerable at lower temperatures (3538). Source

Based on their analysis of tipping cascades, they suggest that a potential planetary threshold could be reached at a temperature increase of ∼2.0 °C above pre-industrial levels and could rise sharply beyond that. They also emphasize that they have taken a risk-averse approach to their analysis because the consequences of exceeding this threshold would be catastrophic. Scientists warn that if we trigger this cascading effect, it would be “an existential threat to civilization”.

To put this in perspective: If all countries were to meet their current pledged emissions reductions, we would still be on track for 2.7°C warming. And many countries are not even close to achieving their promised emissions reductions. So if we want to make sure that we don’t wipe out our civilization, we should do everything in our power to comply with the Paris Agreement. And to have any chance at all of keeping the Paris Agreement, we need to start acting NOW. We only have control over our own future if we don’t trigger this tipping point cascade.

Back to the overview of articles on the climate crisis.

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