Yves here. As readers may have worked out, I am opposed to optimism since that leads to complacency (see The Dark Side of Optimism for a long-form treatment), and even more so when the stakes are as high as the future of what passes for civilization and the survival of species besides ours. So this sort of happy talk about environmental tipping points really pisses me off (admittedly the Iran war has upped my baseline level of choler). But perhaps more climate-change-expert reader can tell me my reaction is too reflexive and there is some merit in the argument below. Perhaps its hedged cheery message (“Things don’t have to be an abject disaster”) is properly calibrated.
By Bela Starinchak, a research associate in the Brando Lab and incoming Ph.D. student at the Yale School of the Environment. Her research focuses on forest resilience in the face of climate and land use change. She is also an alum of the Fall 2025 Young Voices of Science Program. Originally published at Undark
Imagine a Jenga tower, teetering on the edge of collapse as the final, consequential block is pulled. Or a single book standing on an old shelf, finally toppling over after a slight jostle. Or perhaps, as Malcolm Gladwell described in his best-selling book, “The Tipping Point,” a virus, laying low for years until the right set of circumstances convenes, enabling infections to suddenly explode and an epidemic to begin.
In each of these scenarios, incremental, small alterations eventually lead to a tipping point — a moment at which the status quo is no longer sustainable and, in an instant, everything is different. The idea of tipping points, popularized by Gladwell, became mainstream over the past couple of decades. From individual life events to complete transformations of social behavior, tipping points have been described across many contexts and scales. Our planet is no exception.
In the context of the natural world, a tipping point signals a threshold at which the severity and intensity of environmental disturbances (such as deforestation, fire, drought, and permafrost thaw) disrupt an ecosystem’s equilibrium, fundamentally altering its function and composition and exceeding its capacity to return to its balanced state. For example, suppose the balanced state of an ecosystem is a mature, old-growth forest; then its disturbed state would be characterized by widespread tree mortality and a more open canopy. Such tipping points have commonly been depicted as perilous but avoidable.
Yet in 2024, average warming across the globe surpassed 1.5 degrees Celsius (2.7 degrees Fahrenheit) for the first time and the first verified occurrence of a global-scale tipping point happened this past fall (widespread coral reef dieback). These once hypothetical scenarios are becoming our reality. As tipping points become more prevalent, their consequences are still frequently described in vague, generalized, and catastrophized terms, often conveying all tipping points as far-off scenarios that, once crossed, signal an immediate end of our ability to make a difference in conservation and climate change mitigation.
But not all tipping points are the same, and in many cases, their effects can take years to manifest. For instance, systems like coral reefs are highly vulnerable to immediate and irreversible mass bleaching events once a dangerous threshold is crossed, while others, such as glaciers, respond to disturbances like warming at a much slower pace.
As an ecologist who studies the resilience of tropical forests, I have seen firsthand the contrast between common portrayals of a tipping point (and its consequences) and the reality on the ground. I work in the Amazon rainforest, perhaps one of the most well-known examples of a system with a potentially catastrophic tipping point. This idea, dubbed the Amazon tipping point hypothesis by experts, originally estimated that once 40 percent of the Amazon is deforested for agriculture and other human needs, many parts of the Amazon would experience savanna-like conditions. These would consist of a hotter, drier climate dominated by short, scrubby vegetation. The hypothesis also suggested that this change would occur at a lower threshold of 20 to 25 percent deforestation when combined with the stress imposed by changing climate conditions.
Notably, according to recent estimates, the Amazon has reached deforestation levels of about 17 percent, and more than a third of the remaining Amazon has been degraded.
Growing up in the United States, my perception of the Amazon was shaped by nature documentaries like “Our Planet” that featured lush, towering, misty green forests with enticing animals such as jaguars, anacondas, and pink river dolphins. But during my first visit to my lab’s study site, the Tanguro Research Station in central Brazil, what I encountered instead appeared more like the soybean fields of my grandparents’ farm back in Ohio but broken up by large, perfectly rectangular patches of very dry, short forests.
This fragmented landscape I encountered is undeniably an ecosystem in distress. Over time, the dry season for the region has been extended, and days with extreme heat are becoming more frequent. Fire, though not normally a natural occurrence in the Amazon, is prevalent due to widespread human ignition sources and because the hotter, drier conditions favor its establishment and spread in forests. Deforestation reinforces these effects by reducing the extent of cooling and water cycling services provided by trees. Together, such factors are indeed imposing stress on these forests from nearly every angle.
Yet the notion that the Amazon is on the brink of irreversibly transforming into a grassy savanna remains unclear. Results from burn experiments beginning in 2004, in which large swaths of forest at Tanguro were set ablaze to simulate the effects of severe wildfires, suggest that the forest’s future is more complex. Initial findings showed that repeated fires, especially those during the driest months, killed trees and opened the canopy, letting in sunlight. Sun-loving, non-native grass quickly established, and because grass is a much higher fine fuel input for fire, the intensity and severity of each subsequent fire was worse, reinforcing forest loss and inhibiting forest regeneration.
The burn experiment at Tanguro ended in 2010. Since then, the forest has been recovering, and our lab is a part of a huge network of researchers studying what happened next. Remarkably, if you look at the forest now, it looks almost as if it has always been there. Even more notable: The grass that once dominated the understory of the burned areas has nearly vanished.
Forest resilience in action. Top: The effects of 6 years (2004-2010) of intermittent experimental burning on Amazonian forests in Mato Grosso, Brazil. This led to widespread invasion of non-native grass and forest degradation. Bottom: The forest as it stands today, after 16 years of recovery. It now has substantially less grass and more canopy cover, but is still degraded. Visual: Paulo Brando and Leandro Maracahipes
We shouldn’t get ahead of ourselves, though. The forest is still severely fragmented. It’s still next to a heavily managed agricultural field. Droughts and heat waves are more prevalent than ever and are only worsening. We’re still working to understand how the composition and function of the burned forest have changed over time. But after a significant period without fire, the invasive grass-dominated ecosystem that emerged after the fires is almost nowhere in sight.
This aligns with a larger consensus amassed since the creation of the Amazon tipping point hypothesis: There is a lack of clear evidence that a single disturbance, such as 40 percent deforestation, will cause a system-wide tipping point from forest to savanna. Rather, many of these disturbances act like hammers, hitting the system repeatedly. The compounding effects of all these disturbances could potentially cause tipping points, depending on the region, scale, intensity, and timing. But it seems less likely that the state after the tipping point would immediately and permanently be a savanna, and our work shows that if we remove even one of these disturbances from the equation, the forest can still recover. This is why it is so critical that we curb deforestation and improve fire management in the Amazon and forests across the globe.
On a broader scale, even if we’ve passed 1.5 degrees of warming, our planet is resilient. In many cases, if we act diligently to cease disturbances, promote resilience, and reduce the time a system spends beyond its tipping point, it could still have the capacity to recover. And this is the message that the general tipping point conversation fails to capture.
Fortunately, we know ways to foster resilience in natural ecosystems, and communicating these as powerful post-tipping point tools can instill a hopeful message in an otherwise heavy conversation. Conservation, restoration, and centering and supporting the knowledge and actions of Indigenous and local communities who live in the ecosystems that are at risk — all of these are uniquely vital.
Importantly, this doesn’t mean that the concept of tipping points isn’t useful. Thresholds and clear numbers grounded in scientific research are incredibly impactful for clear management and policy guidance. But conveying the significance of sustained conservation action, intervention pathways, and a positive, actionable message after passing a tipping point is just as crucial.
So the next time you hear that we’ve passed a point of no return, don’t despair. These tipping points are not always the instant, unstoppable dominoes they’re portrayed to be. Dig deeper, ask questions, find out what you can do, and most importantly: Don’t lose hope.
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As I see it, a tipping point, in very general terms, is best interpreted as a moment in which a second derivative turns from negative or zero to positive; in other words, when positive feedback loops are established (as such, it in fact regards the third derivative). Strictly considering the mathematical/cybernetic points, they’re neither bad nor good, which is a point that can only be decided by the ones who are doing the interpreting. I think the piece, though it has some decent points (and I admit to being a little happy at finding out that at least on the small scale ecosystems, when left to their own devices, can more or less reconstruct themselves) is a tad too sanguine. The problem is not whether the forest will recover or not; the problem is that, once enough forest goes (or enough CO2 is in the atmosphere, etc.), all our previous knowledge becomes more or less useless and the system can become violently unstable, since positive feedback loops amplify the magnitude of small perturbations.
Taking into consideration strictly the point about ecology, I think the framing is misleading; it could be argued, and this is simply a made-up example, that even if the Amazon died that rains in the Sahara would then create a forest there and thus we’d be more or less the same. Maybe in a strict accounting sense, but this is hardly a reasonable thing to say to the inhabitants of the Amazon (and potentially of the Sahara as well). So I would be cautious with any such conclusions. Keynes had it right: “we simply do not know”. But do we really want to gamble with whatever radical outcomes can result from these positive feedback loops?
Yves, open italics alert.
Observing resilience in the rainforest is really good news, refining that observation to a broad brush question of how we understand tipping points looks a bit like hopium, even if it’s a useful exercise. No two tipping points involve the same set of variables. The rainforest example involves an enormous living thing which fights back. The clouds loop is strait chemistry performed in the sky.
Fixed, thanks!
We know now that rainforests in many cases are far more resilient than presumed – many forests in south and central America that were thought to be primal we now know to have been cleared farmland in centuries past.
The issue with tipping points is less than they set us on an unrepeatable path, but the speed of the transition. What we really don’t know is how fast and how dramatic climatic change may be at a local, regional or global scale. Geological records are not very reassuring – past switches in climate have often been remarkably fast, taking just years, not decades or centuries.
The good news though is that Trump has seen the light and is now doing his best to destroy the fossil fuel industry.
Bela Starinchak writes:
“…if we act diligently to cease disturbances, promote resilience, and reduce the time a system spends beyond its tipping point, it could still have the capacity to recover.”
~~~~~~~~~~~~
“Waterbury, Vermont voters will weigh a bond this March 3, 2026 Town Meeting Day for a project town leaders have called “the only meaningful option” to soften the impact of future floods.
The Washington County town sits on the banks of the Winooski River and has suffered repeated flooding since Tropical Storm Irene devastated its downtown in 2011.
At the heart of the proposal is a 45-acre parcel of state-owned farmland called Randall Meadow, or just “the cornfield,” along the river, near the state office complex.
The town is proposing to excavate the field, hauling out some 100,000 cubic feet of soil in thousands of dump truck loads.”
And on Town Meeting day; “Waterbury voters have approved a $4.3 million project to excavate a field next to the Winooski River. Town leaders have called the project — which will entail removing soil in thousands of dump truck loads — “the only meaningful option” to mitigate future floods.”
Maybe I’m misunderstanding the Tanguro example. I don’t doubt the forests ability to recover until wildfires reach an occurrence threshold. I just don’t understand why looking at the forest patch 10 years after the systematic burns have stopped provides insight into that forest resilience in a warming globe, considering that a more realistic scenario for the future of that area would be continual unabated fires. Wouldn’t four years of fires or so into that study provide a more realistic view of the future?
Tipping points are where a stable dynamic system is disturbed to the point where it will not return to its prior stable state. And it may under go extremely dramatic changes that cause the new stable point to look dramatically different from the old state of the system.
All dynamic environmental systems are under going constant disturbances, large and small. Once disturbed enough they will seek a new stable point. And that new stable point may look pretty inhospitable to the species that were adapted to the old stable state.
So we, as one of those species adapted to the relatively stable environment of our entire history and prehistory, should be greatly concerned if those global tipping points might mean that in relatively short order we find that, as a major shift to a new stable global environmental state is occuring, we find ourselves living in the wrong places, depending on the wrong food sources, and living on a planet where the average atmospheric temperature is inhospitable to us.
The author confuses the resilience of one small part of the, disturbed but still ‘stable’, current global environmental state with the idea that that means global tipping points will exhibit similar stability once the system starts to seek a new global stable point. That’s why they are called tipping points.
You break it, you bought it
There is no argument that Nature can’t at least partially recover when the jackboot of human civilization is lifted off her neck. The fall and rise of the Tanguro Park is the same as has happened in northwestern Costa Rica, when Santa Rosa National Park was protected and incorporated into the Guanacaste Conservation Area. Cattle ranches were closed, and dry season fires (all human set) were suppressed and even with a normal six-month dry season, forest regrowth has transformed the area as much as in the two Tanguro photos.
While mammal populations have increased and spread out into the recent forests, all is far from well. Insect populations have dramatically decreased in the last few years, and areas of cloud forest have visibly shrunk as cloud cover of the volcanos has retreated upward with increasing global heating. The Conservation Area enjoys protected status; to the east unprotected lowland forest was massively clearcut during the “hamburger connection” years of the 1980’s but recovered when fast food joints were pushed by activists to be a little more circumspect in their beef sourcing. This eastern forest recovery is unravelling again as export agricultural schemes are being pushed into the regrown forests.
So far tipping points haven’t happened “everywhere, nor all at once”. Yet. But that doesn’t mean we’re not on the “Rocket Sled ride into the Abyss” (h/t to Mike Duncan’s History of Rome for that image).
Daniel Brooks, co-author of The Darwinian Survival Guide:
> As we discuss in DSG, we know of no other conservation effort in the world that integrates the principles of convivial conservation, the evolutionary commons, and the Four Laws of Biotics better than the Área de Conservación Guanacaste (ACG) in Guanacaste Province, Costa Rica. The ACG is a UNESCO World Heritage site and considered a model for its revolutionary approach to conservation that, when it began in the 1980s, was unique and far outside the status quo approach of “put a fence around it and keep people out.” To be truly wise in interacting with the biosphere, humans must be better integrated with nature, not more separated from it. At the same time, we need to give biodiversity room to move, to explore species’ evolutionary potential and inherent capacity to cope with change by changing. By virtue of its sheer size and diversity of habitats, connectivity of those habitats, and symbiosis with surrounding communities, the ACG is currently functioning as an evolutionary commons for neotropical biodiversity and the humans that live around it. It is a spectacularly successful example of the value of a Darwinian approach to conservation.
Brooks approach has optimistic and not-optimistic sides. The optimistic side, we are not killing off life on this planet, and civilization has a chance to survive in smaller, circular-economy cities (megapolises are meat zones for epidemics). The not-so side is that survival is dependent on both mass migration and tiny isolated niches, and evolutionary processes can kill billions along the way. Extinction is avoided by variants being selected in what can be an unkind process.
The canary just died
Send down another canary
The idea of stable, balanced, or self-regulating ecological systems is a bit misleading. Data purporting to show progress toward singular, ideal environments that fit neatly into concepts like “savannah”, “tropical rainforest”, or simply “what this planet looks like with X amount of greenhouse gases and Y amount of human (or other species’) intervention” are very likely just brief snapshots on the Z-Axis of Time. Even the concept of a “system” itself, with its ties to computational theory and cognitive behavior analyses, is very questionable when discussing the myriad interactions between living species and non-living planetary phenomena, since it tends to imply a particular order of operations when each variable is “working” as intended.
A possibly better visualization of planetary/species interactions and cycles, based on what I learned in grad school, is the simple web. You pull on one strand of the web (e.g. planetary warming caused by solar insolation interacting with greenhouse gases), and each other strand responds with a particular amount of strain, depending on each strand’s proximity to the “pull”. One way to name these pulls is to call them forcing agents, which can create positive feedback loops along individual strands when the initial force is repeated enough times to continue pulling without additional input. Greenhouse gas use could go to zero today, and the feedback loop would continue for some time. Now imagine tens or dozens of pulls/forcings occurring simultaneously, across each and every strand of the web. At some point, individual connections are liable to break, which could be thought of as a “tipping point”, since repairing that connection still has to find a way to deal with the continual strain on each strand that the broken link is supposed to be connected to. For example, once the planet’s oceans have used up their ability to act as carbon sinks, carbon must find somewhere else to go. There is no more connection between sink and ocean.
Recall that the web is circular, and connections to other variables are numerous. It may not be impossible to reconnect “broken” interactions, but there is no inherent driver for those connections to always repair themselves, as the balanced and self-organizing system concept would have us believe. Much more likely, a new connection will form out of the broken strands of the old connection, and become something that we humans do not think of as “correct” or “balanced”. I believe our role is to consider how we and all other species can potentially become resilient to the new connections, as well as how we can promote long-term survival enough so that new species can come about to replace the diversity that we are so successful at killing off.
I find the role of “chaos theory” to be ignored in discussions of the environment and climate change.
“Chaos theory is an interdisciplinary area of scientific study and branch of mathematics. It focuses on underlying patterns and deterministic laws of dynamical systems that are highly sensitive to initial conditions. These were once thought to have completely random states of disorder and irregularities.[1] Chaos theory states that within the apparent randomness of chaotic complex systems, there are underlying patterns, interconnection, constant feedback loops, repetition, self-similarity, fractals and self-organization.[2]” – Wikipedia-“chaos theory”
If you look at clouds you can see some look linear (streaks), some look semi-logrithmic (streaks with curves at the end), some look cyclical (such as herringbone clouds), and many other shapes. But if you look at the jet streams from space they can look like a string flapping in the breeze. These are chaotic motions and cannot be predicted for more than a few days. But these have a great deal to do with our daily and long-term weather.
So much of what I read about climate change appears to be based on greenhouse gasses and assuming that reducing them will return the weather to pre-industrial times. But with much of the weather being chaotic there’s no certainty that reducing greenhouse gasses will return it to anything recognizable. In fact, reducing greenhouse gasses now may turn the weather into something even more intolerable. Where tipping points are treated as singularities, the chaos in weather is far more complex.
It is true that “not all tipping points are the same.” However, going from there to discuss the tragedy of the worldwide bleaching of coral reefs is missing a key point. The world as we know it will not come to an end without coral reefs, although many people’s income and food supply will suffer. The key point is that many tipping points may be much larger in total effect than losing our coral reefs. Glaciers melting slowly is not a sign that melting glaciers are not a dangerous tipping point. Many communities around the world are in danger of losing their water supplies when the local glaciers finally finish melting and their runoff becomes a seasonal flow instead of a reliable river. Exhibit A is the Ganges River. Huge amounts of methane are frozen in the ground and sea in and around the Arctic Ocean. Siberia is already experiencing massive explosions of melting methane. Acidification of the oceans may cross a tipping point where calcium can no longer by turned into bones and shells in the ocean. Good news for jellyfish? Global warming, unlike Trump’s Iran folly, is not a threat of immediate extinction for the world (nuclear winter, etc.). Finding good news in the short run does not negate the huge longterm threat to life and civilization (especially).