Today I would like to highlight new research published in the world's premier science journal, Nature. A paper in the latest edition by Paul D. L. Ritchie, Joseph J. Clarke, Peter M. Cox and Chris Huntingford offers an important revision to how we think about a future scenario in which we do not reduce the emissions currently heating the planet.

The conventional wisdom is that without concerted international efforts, there is some point when the average global temperature will cross a threshold of (more or less) 2 degrees Celsius above the pre-industrial period. It has been assumed that, at +2 degrees, we will cross a "tipping point" that will set us on an irreversible course to a new climate that will evolve steadily over time (and not in our favor).

This new research provides a more nuanced view of how climate change is playing out and what to expect in the future. The first concept the authors explain is the idea of a "tipping element," which is an environmental change that would take the world across the climate change tipping point:

Multiple strands of evidence indicate that components of the Earth system, called tipping elements, are capable of large and rapid changes in response to relatively small changes to forcings. Tipping elements are often irreversible over multiple human generations: the original system state is not recovered when the forcing is brought back to its original value. The point beyond which a tipping element changes state is called a tipping point. Tipping points are evident in palaeoclimate records, as well as in future projections made with Earth system models.

The researchers note that there are two kinds of tipping elements: fast-onset and slow-onset:

Once global warming passes a threshold for the system, the current state of the system starts to undergo a transition to an alternative state, and such a state might be vastly different. This transition may occur relatively quickly; we refer to these as having a fast-onset tipping point, and hypothetical examples include Amazon forest dieback and disruption to monsoons Other transitions may take much longer, and these slow-onset cases include ice sheet loss and the collapse of the Atlantic Meridional Overturning Circulation (AMOC).

Put another way, some tipping elements, once "tipped," will change the world's climate relatively quickly and other elements more slowly. This is an important point, because we are in a much worse situation if we are pushing fast-onset tipping elements across their change thresholds instead of slow ones. The distinction is critical for another reason, which has to with a proposed change in how we see tipping points themselves.