Close to the tipping point?

Source: Science, Vol 377, Issue 6611, https://doi.org/10.1126/science.abn7950

The Canadian journalist Malcolm Gladwell popularized the phrase “tipping point” in his bestselling book of the same name. “The tipping point is that magic moment when an idea, trend, or social behavior crosses a threshold, tips, and spreads like wildfire,” he wrote. 

The book, published in 2000, examines how some seemingly minor social trends, fads and ideas go mainstream, seemingly overnight. Often an idea will creep towards some sort of critical mass before becoming contagious, much the same way a virus does, Gladwell argues. 

These tipping points can be thought of like a car speeding towards the edge of a cliff. There is danger ahead and at a certain point the car will still be on the cliff, but no amount of slowing or swerving can keep it from going over the edge. 

For decades, climate scientists have been carefully monitoring, and trying to pinpoint, exactly where some of the Earth’s tipping points are. In other words, just how much ice must melt before things become irreversible? How much carbon can really be in the atmosphere before temperatures dramatically accelerate? And, most topically given COP30’s location in Belém, Brazil, just how much of the Amazon rainforest (see page 14) can we afford to lose before there is no way to ever bring it back again? 

A 2022 article in the journal Science highlights that since average global warming temperatures have exceeded 1°C above pre-industrial levels, we are already at risk of triggering some tipping points. The paper identifies 16 global and regional tipping elements. According to the article, exceeding the 1.5°C level targeted by the Paris Agreement would likely tip between six and ten of the 16 (see map). As the planet exceeded that mark last year, according to various observers, we will get a front row seat to see if the 2022 predictions turn out to be accurate. 

Knowing where these climate tipping points are becomes all the more necessary if we are to avoid them. 

One such effort was launched at COP28 in December 2023: the Global Tipping Points Summary Report identified more than 25 parts of the Earth system that have tipping points. Some are very close already, like the collapse of the Greenland ice sheet, the Great Barrier Reef die-off and, of course, the ever-shrinking Amazon rainforest. 

Led by the University of Exeter’s Global Systems Institute and supported by more than 200 researchers, the Global Tipping Points Report also issued a number of recommendations to stave off the rush towards those tipping points such as phasing out fossil fuel and land use emissions and creating policies for positive tipping points, such as accelerating investment in renewables in the Global South. 

Yet one problem around any sort of tipping point is identifying where, exactly, that point is. A recent episode of The Economist magazine’s science and technology podcast about climate tipping points mentions that some models predict that the Greenland ice sheet will irreversibly start melting when global temperatures rise above 0.8°C above pre-industrial levels while other models state that point will occur at a 3°C increase. One issue is that the former temperature has been reached decades ago while the latter temperature might never be reached. No one doubts that protecting the ice sheet from melting is essential, but so is knowing if it is too late to do anything about it. 

The UK’s Advanced Research and Innovation Agency, which funds research and development across a range of areas, is working on a £81 million program Forecasting Tipping Points, which aims to develop an early warning system to detect climate pressure points before they arrive. The 26 teams of experts assembled within the program will work on a variety of projects which include using drones to better collect data on Arctic ice, deploying wind-propelled robots to monitor the ocean atmosphere and connecting subsea sensors with satellites to develop an automated data collection system that doesn’t require human intervention. The point of many of these projects is to have as many eyes on as many things as possible, so if something starts to shift in, say, an ice sheet or an atmospheric reading, you can be ready to counter it. 

A quarter-century after his breakout book, Gladwell published a follow up that looked at topics like COVID-19, the opioid crisis and social engineering. His Revenge of the Tipping Point from 2024 revisits many of its predecessor’s concepts that could easily be applied to the challenges surrounding climate tipping points: “If change happened gradually, you could see that you were getting closer and closer to your goal – and you wouldn’t be surprised when you reached it,” Gladwell writes. “But if nothing happens and then everything happens, you are in the strange position of being discouraged during the long stretch when nothing is happening and stunned at the point when it all shifts.”