Climate tipping points are the looming specter of our future, beyond which Earth’s systems switch to new states, often abruptly and irreversibly changed.
The long-frozen soil beneath the North Pole can thaw rapidly, releasing large amounts of carbon dioxide. methane It builds up inside and further heats the atmosphere in a feedback loop. Rapid melting of fresh water from Greenland ice (one tipping point) disrupts Atlantic circulation patterns (another tipping point) Weather is chaotic around the world: Temperatures could drop in northern Europe, the tropics could overheat, wet and dry seasons could reverse in the Amazon, and parts of the east coast of the United States could be submerged by rising sea levels.
a new paper The journal Nature Climate Change argues that all these alarming events should be called something other than “tipping points.” This framework aims to draw attention to the fundamental changes that global warming may bring. But a group of scientists from cities across Canada, the UK, Switzerland and the US say the concept is scientifically inaccurate and, worse, could backfire.
Bob Kopp, a study co-author who studies climate change and sea level rise at Rutgers University, said talking about tipping points, while scary, doesn’t motivate people to do anything about climate change. He said it might be possible. That’s because fear is an unreliable motivator. It may be the key to getting noticed online, but too often it can leave people feeling defeated and demotivated. “Tipping points are not an inherent property of the world as a way of looking at it,” Kopp said. “Whether or not you use that framework is a choice.”
The popularity of this metaphor skyrocketed after pop science author Malcolm Gladwell published this book. turning point In 2000, it was inspired by ideas from epidemiology to prepare for the moment the virus started spreading explosively. “I remember hearing this phrase for the first time and thinking, ‘Wow, what if there was a tipping point for everything?'” Gladwell Told in 2009. “Wouldn’t it be great to look for tipping points in business, social policy, advertising, and other fields outside of medicine?”
The concept was quickly embraced by scientists trying to sound the alarm about global warming. “We are on the precipice of a tipping point in the climate system, beyond which there is no going back,” said climate scientist James Hansen. Lecture at the American Geophysical Union Three years later, climate scientist Tim Renton co-authored a much-cited paper that assessed: How close is the world to various tipping points? For example, when the lush Amazon rainforest may turn into an arid savannah, or when the underside of the West Antarctic ice sheet may be eroded by warm water and collapse into the ocean. (Climate researchers have also applied this idea to cultural trends that help reduce emissions, called “social tipping points,” such as promoting electric cars and plant-based diets.)
Kopp said highlighting climate tipping points might have made sense as a call to action 20 years ago, when the effects of climate change were less obvious. But in 2024, the hottest year on record, the effects are clear: floods, fires, and heatwaves are significantly worse than before. “You only have to open a newspaper to learn about the dangerous effects of climate change,” Kopp says.
Disasters like this can cause some sort of collective realization May lead to policy changeslike New York City Pours resources into climate adaptation after Hurricane Sandy Kopp said a tipping point won’t generate such a response: “We’re never going to stand up and say, ‘Today is the day the West Antarctic ice sheet collapses.'” You better do something about it. ”
Although Renton’s research has influenced how people think about climate tipping points, Kopp’s paper misrepresents the efforts he and his colleagues have made to clarify the meaning of tipping points. He said he was telling. “Most importantly, tipping points are real and well established in both climate and social systems. Readers of this paper may be under the false impression that tipping points do not exist. ,” said Renton, who now studies climate change and Earth systems at the university. he said in an email from Exeter, England.
According to Renton’s personal experience, framing “tipping points” helps people understand the risks of climate change. “What I find disappointing about this paper is that, as is often the case, some members of the climate change community are willing to defend their common interests against well-organized opposition. “We are choosing to argue with each other rather than working together constructively,” Renton said.
The 2008 Renton paper argues that the “increasing political demand to define and justify binding temperature targets” warrants consideration of what changes the climate system is likely to bring about. It became. However, it is still unclear how much of a tipping point global warming will actually cause. Consider, for example, the possibility that the conveyor belt of Atlantic ocean currents that distributes heat and regulates temperature from the equator to the poles and vice versa could slow down significantly. A 2022 study found that the collapse threshold is: For temperatures between 1.4 degrees Celsius and 8 degrees Celsius.
Yet the tipping point is being confused with the international goal of keeping global temperatures below 1.5 degrees Celsius (2.7 degrees Fahrenheit). Kopp and his colleagues found numerous references to the 1.5 degree Celsius tipping point, not only from scientific studies but also from the news. However, the temperature threshold for catastrophe is highly uncertain. What is certain is that the risks continue to increase with every slight increase in global warming.
“The scientific community has been telling us that 1.5 degrees Celsius is the tipping point, and if people think that nothing happens when we go above 1.5 degrees Celsius, then the reality is that we face many of the dangers of climate. “It can threaten the credibility of science when it changes,” Kopp said.
He’s not saying people should be silent about the tipping point the world is facing. He simply wants a different term, something like “potential surprise.” However, given the widespread appeal of the term “tipping point,” which has so far appeared in more than 2,200 scientific papers, switching to a new term will be a major challenge.
