Dangerous Climate Tipping Points Will Affect Australia

We don’t yet fully understand what global climate tipping points mean for Australia. But we know enough to conclude the impacts of passing one or more tipping points must now be considered.

In 2023, there was a surge of news stories about climate tipping points, including the accelerating loss of Greenland and Antarctic ice sheets, the potential dieback of the Amazon rainforest, and the likely weakening of the Atlantic Meridional Ocean Circulation. These elements are among nine recognized global climate tipping points. Once a tipping point is crossed, changes are often irreversible for a very long time. In many cases, additional greenhouse gases will be released into the atmosphere, further warming our planet.

New scientific research and reviews suggest at least one of Earth’s “tipping points” could be closer than we hoped. A milestone review of global tipping points was launched at last year’s COP28.

What will these tipping points mean for Australia? We don’t yet have a good enough understanding to fully answer this question.

Our report, released overnight, includes conclusions in three categories: we need to do more research; tipping points must be part of climate projections, hazard, and impact analyses; and adaptation plans must take the potential impacts into account.

Climate scientists have known for a while, through paleoclimate records and other evidence, that there are “tipping elements” in the climate system. These elements can undergo an abrupt change in state, which becomes self-perpetuating and irreversible for a very long time.

An example is the loss of Greenland ice. Once ice is lost, climate feedbacks lead to further loss, and major ice loss becomes “committed”. It becomes unlikely the ice sheet will reform for tens of thousands of years and only if the climate cools again.

Triggering climate tipping points would lead to changes in addition to those commonly included in climate projections. These changes include a significant rise in sea level at double the rate (or even more) of usual projections, as well as extra warming, altered weather systems, climate variability, and extremes.

Cutting fossil greenhouse gas emissions is the most important thing we can do to limit warming and the risk of triggering tipping points. The faster we reduce emissions, the better our chances.

But as the planet continues to warm, we must consider the consequenc