A new paper published today in Nature Communications suggest that “shifts in Earth ecosystems occur over ‘human’ timescales of years and decades, meaning the collapse of large vulnerable ecosystems, such as the Amazon rainforest and Caribbean coral reefs, may take only a few decades once triggered.” This putative behaviour of environmental systems is sometimes described as revealing ‘tipping points’ in the climate system.
But is the concept of ‘tipping point’ helpful for describing and communicating possible climate futures?
This question is one of 15 that are debated by leading scholars in my new book Contemporary Debates in Climate Change: A Student Primer. In Chapter 2 of the book, climate scientists Michel Crucifix and James Annan debate this question. The concept and terminology of tipping points has been widely used to invoke the danger of passing thresholds of irreversible and/or abrupt change in the near immediate future. But how helpful is this metaphor for climate science and for climate change communication?
Michel Crucifix argues that the tipping point concept may have some limitations as a description of the mathematical behaviour of Earth System models trying to simulate the world’s climate. But it’s use can alert decision-makers to the possibility of some rapid and/or serious changes in the climate system which need attention as part of responsible and accountable policymaking.
In contrast, James Annan argues that the concept risks exaggerating the immediacy and severity of climate change and offers a false prospectus of there being a ‘cliff edge’ within the climate system. Climate change is primarily a problem of incremental cumulative harm and the concept of tipping point offers a false emphasis on immediacy and abruptness and harms the public understanding of climate science.
Other debates in the book include: whether climate change is the most important challenge of our time, whether carbon markets are essential for addressing climate change, whether climate change is a human rights violation and whether social media make constructive climate policy-making harder.