I’m writing this in the last days of the northern hemisphere’s autumn in 2025. Over recent weeks we’ve seen a hurricane hit Jamaica with wind speeds a few hundred feet above sea level topping 250 miles per hour and a rainstorm in central Vietnam that dropped a nearly unprecedented five feet of rain inside of twenty-four hours. The Iranian government is currently weighing whether to evacuate Tehran after unending drought has all but cut off its supply of water. Earlier this year, new data from NASA revealed that there has been a “dramatic rise in the intensity” of such events, as The Guardian put it: “The study shows that such extreme events are becoming more frequent, longer-lasting and more severe, with last year’s figures reaching twice that of the 2003–2020 average.”

Another new study casts some light on why such things keep happening: the veteran climate scientist Michael Mann and his colleagues found that the number of “atmospheric wave events” that cause extreme weather has tripled in the past seventy-five years, as jet stream winds slow and become stuck in unusual patterns for long periods, leaving the land below either baking in sunny drought or drenched in flooding rains. That in turn happens because we’ve melted so much ice in the Arctic that the temperature differential between the equator and the poles, which drives the jet stream, has shrunk. It’s not good news that we’re messing with systems as large as the jet stream—or the ocean’s Gulf Stream, which, according to new research, has been weakening for decades and threatens to flicker and falter in the years ahead.

New data of this sort emerge constantly (though their frequency will doubtless decline as the Trump administration shuts down agencies and disables satellites; in the week before Christmas it announced plans to break up the National Center for Atmospheric Research, a research lab that helps lead the world’s effort to understand global warming, because it was “one of the largest sources of climate alarmism in the country”). The Intergovernmental Panel on Climate Change sums up the new research every five years or so in a mammoth report, but it has recently taken to issuing smaller interim updates with the latest science. This year’s version came out in June and was not heartening. As one of the authors, the climate scientist Zeke Hausfather, explained to The Washington Post:

Things aren’t just getting worse. They’re getting worse faster. We’re actively moving in the wrong direction in a critical period of time that we would need to meet our most ambitious climate goals. Some reports, there’s a silver lining. I don’t think there really is one in this one.

The report predicted that we will pass the 1.5 degree Celsius warming mark—the limit set by the Paris Agreement less than a decade ago—in the next couple of years. At current rates of carbon emissions, we have about twenty years before we push past two degrees Celsius.

It’s difficult to understand the impact that amount of warming will have on our planet. So it’s useful—extremely useful—to turn to the geologic record and figure out where we stand in the grand scheme of things, and that’s where the journalist Peter Brannen has done us a very good turn. After writing a powerful book, *The Ends of the World *(2017), on the history of mass extinctions, Brannen has now rolled his understanding of deep time into what I suspect will be an enduring volume, *The Story of * CO 2 Is the Story of Everything. I know that you have been promised the story of everything before, only to read an account of rice, or salt, or gunpowder, or cod, or some other interesting commodity. But carbon dioxide is the real deal. If you go back pretty much to the beginning of everything—and Brannen does—you find carbon dioxide lurking in the shadows, controlling events with a power that the Illuminati (or the cod) could only envy.

The Scottish chemist Joseph Black discovered the gas only in the eighteenth century, but it’s been the prime mover for a lot longer than that. First, its molecular structure traps heat from the sun that would otherwise radiate back out to space. This makes CO2 the “principal knob governing earth’s temperature.” When there’s a lot of it in the atmosphere, the earth is hot; when it dwindles, the earth turns cool. Second, photosynthetic organisms use photons from the sun and water to “transform carbon dioxide from the air around [them] into the stuff of life,” Brannen writes. “In this way, energy, once forged in the thermonuclear center of the sun and radiated across the vacuum, was diverted into the world of the living, through the chemistry of CO2.” Energy imbalances tend toward equilibrium, and multiple mechanisms on earth gradually dissipate the solar energy constantly bombarding the planet—hurricanes, for example, but also life itself, which captures this energy and metabolizes it over time into radiant waste heat.

Brannen observes this dance across vast swaths of time, tracing the likely beginnings of life on the planet and the evolution of photosynthesis in microbes as much as three billion years ago, which led to the Great Oxidation Event, a period of higher atmospheric oxygen that was followed by the long Boring Billion, which he describes as “a span of geologic time from 1.8 billion to 850 million years ago so seemingly uneventful that it sits in sublime Zen-like equipoise, a cosmic void in Earth history. This was a planet stuck in second gear.” (Brannen is an adept writer, handling technical subjects with grace and never reaching for the pat or the sentimental.) Along this journey through the great geologic periods of the past—the Tonian, the Cambrian, the Ordovician, and so many others etched in the walls of canyons—we learn about how oxygen eventually accumulated in the atmosphere and how photosynthesis as we know it today arose.

We also see the gun that will go off in our own time—the formation of the vast deposits of oil, gas, and coal laid down over millions of years as seas expanded and contracted and plant and animal life flourished and died off. In the Carboniferous Period, for instance, 359 to 299 million years ago, oxygen levels were so high that in a warm, flooded Appalachia,

endless swamps throbbed with the deafening drone of gigantic insects and often exploded into wildfire—even waterlogged. This great age of coal is a bizarre sliver of geologic time that accounts for a mere two percent of Earth’s history, but 90 percent of its coal.

In the Silurian Period, 444 to 419 million years ago,

hot, algae-choked seas soared hundreds of feet, drowning what were once the desolate glacial outwash plains of Saudi Arabia. This sickly high tide of extinction left behind so much dead life that today Silurian sunlight and CO2 flare from the derricks of the largest gas fields in the world, from Libya to Iran.

It was in the Devonian Period, 419 to 359 million years ago, that the roots of the first forests began breaking up rock and unearthing phosphorous, which, when it washed downriver to the sea, ignited blooms of algae that eventually became the fracked gas of North Dakota. And so on.

There have been five great mass extinctions on this earth, and except for the last one, which was triggered by the asteroid strike that killed the dinosaurs, all have been the result of carbon dioxide flooding into the atmosphere and raising the temperature. It takes a lot to produce a mass extinction. Glaciers covering North America didn’t do it, nor have Yellowstone supereruptions,

three of which have detonated in a little over the past two million years—each of which would have devastated modern agriculture and industrial civilization, but none of which had any effect on global biodiversity.

No, to really trigger an extinction crisis you usually need something called, innocuously enough, a “large igneous province.” These provinces are “huge CO2-spewing volcanic expanses, quite unlike anything in human history, which can vomit millions of square miles of basalt lava across entire continents.”

Brannen describes the very worst of these—which caused the mass extinction at the end of the Permian Period, 252 million years ago—in loving detail. The action was centered on Siberia, where enough lava erupted that it could have covered the lower forty-eight US states a kilometer deep. But here’s what’s scary: it “wasn’t until 300,000 years into the eruptions, and after two-thirds of this lava had already erupted…that this worst mass extinction of all time actually began.” The eruptions and storms of acid rain weren’t enough to wipe out life on their own. Eventually rising magma started “spreading sideways into the rock far underground, like incandescent rhizomes, baking the underworld.” And there the fire found “carbon-rich limestones and natural gas deposits from ancient seas, and coals from ages past.”

It found, in other words, fossil fuels, and it began to burn them quickly. As a result this vast volcanic field, known as the Siberian Traps, “suddenly started to emit far too much CO2, and far too quickly for the surface world to accommodate.” Over thousands of years the temperature rose about ten degrees Celsius. The oceans got not only hotter but more acidic, as the CO2 in the air was absorbed into the seas as carbonic acid, which destroyed organisms like clams and corals that had carbonate shells. Trilobites, “the scuttling sea bugs whose calcite eyes and intricately louvered armor had littered the seabed for hundreds of millions of years—by the uncountable hundreds of trillions—disappeared forever.” In all, 96 percent of life may have disappeared from the oceans, which could have been hot enough to power five-hundred-mile-per-hour “hypercanes.”

Terrestrial life, when not being lashed by storms like these, faced extreme drought and heat and was burned by wildfires. Before long, you could have walked the continents without encountering a tree. Eventually, Brannen writes, “the interiors of the continents were silent except for hot, howling winds that swept over the wastes.” The oceans asphyxiated.

Every gear of the grand, intricately interlocking biogeochemical machinery of this planet became jammed, decoupled, or spun hopelessly out of control. Complex life, as a subset of this global geochemical churn, unraveled as well. All from adding too much CO2.

You can guess, I think, where this is going. As Brannen writes, “If there is a geologic precedent for what industrial civilization has been up to in the past few centuries, it is something like the volcanoes of the End-Permian mass extinction.”

At first that might seem unlikely—the Siberian eruptions, after all, put somewhere between 30,000 and 120,000 gigatons of CO2 into the atmosphere, and humanity, even if it did its damnedest, could put only about 18,000 gigatons of carbon dioxide aloft. But it turns out we’re in our own way even more efficient than those End-Permian eruptions: “The best estimate is that we’re emitting carbon perhaps ten times faster even than the mindless, undirected Siberian volcanoes that brought about the worst mass extinction ever.” And this speed matters. Given time, the planet can buffer huge amounts of CO2. For instance, as it gets hotter, the air can hold more water vapor, and rain increases. This rainwater, which contains dissolved CO2 in the form of carbonic acid, weathers rock and, in the process, converts CO2 into bicarbonate ions that are easily stored in the seabed, essentially washing it from the atmosphere to the depths. But all of that takes time, and

the rate at which humans are currently injecting CO2 into the oceans and atmosphere far surpasses the planet’s ability to keep pace. We are currently at the initial stages of a system failure. If we keep at it for much longer, we might see what actual failure means.

Brannen spends the last third of this long book explaining

how an ice-age creature, whose evolution was shaped by fire, eventually came to be a geologic force on par with large igneous provinces, one that now emits 100 times more CO2 every year than all the volcanoes on Earth.

Though this part of the story is well told, I think it will be the most familiar to readers, as we go from the discovery of fire and the acquisition of speech to the rise of different political formations, the development of agriculture, the Roman Empire, and the Dark Ages. Brannen’s focus is at all times on energy and on the truly remarkable story of how a species that had long depended mostly on muscles (its own and those of its domesticated animals) eventually “burst through” those energetic limits, “unleashing 500 million years of sunlight stored in organic carbon.” If you haven’t read accounts of, say, James Watt and the steam engine, Brannen’s is entirely credible and well written. But the important part is really the conclusion: “Today, humanity produces more CO2 than all the other substances we produce on earth combined.” Considering that we produce 1.2 billion metric tons of corn and four billion metric tons of cement every year, that’s saying something. “From a planetary perspective, human society is now, above all else, a conduit for moving carbon in the crust into the atmosphere. CO2 is what we make.”

And it may well be what unmakes us. To me, one of the curiosities of global warming is that we developed the tools we needed to understand it precisely in time. We began monitoring CO2 in the atmosphere in 1958, and by the 1970s we had the supercomputers to begin the task of understanding how dangerous it was. In 1988 NASA’s James Hansen explained to Congress that climate change was underway and would soon be the dominant fact of life on our planet. More or less simultaneously, we began to develop the set of tools that might change our civilization from a carbon-spewing combustion machine into something more sustainable; the first solar cell was invented at Bell Labs in New Jersey in 1954, and some seventy years later it has become the cheapest form of power generation on the planet. Far more efficient than photosynthesis, it takes photons from the sun and transforms them into electricity, which can in turn be transformed into motion, heat, cold, and many other things we might need. I think Brannen probably underplays the possibility of a quick and remarkable solar revolution. He’s right that we are a species marked by combustion, but we could pretty quickly douse most of those flames: the electric vehicle renders the spark from the spark plug archaic; the heat pump means you needn’t have a tank of flammable hydrocarbon in the basement; the induction cooktop means you no longer require a campfire in your kitchen.

In other words, if we wanted to do something right now to end our career as a geological force and instead live off the daily increment of sunlight that arrives on earth, we could. China installed ninety gigawatts of solar capacity in May alone, the rough equivalent of the capacity of ninety coal-fired power plants—more than any other country installed in all of 2024. China can produce solar panels at even higher rates and sell them to the rest of the world for prices so low that in some places they are now used for fencing (less efficient at producing power than those installed on roofs, but when they are so cheap, why not?). That this is a threat to the three-hundred-year reign of fossil fuel can be deduced from the incredible efforts of the hydrocarbon industry to head off the transition. Having done much to elect Donald Trump, its leaders—such as the secretary of energy, a former fracking executive—now counsel him as he and the GOP Congress pass law after law to make clean energy expensive and to make oil and gas easier to pump. They’ve even, over the course of a few months, taken down many of the tools that help us understand our dilemma: the NASA offices where Hansen worked have been shuttered, the satellites that tracked shrinking ice sheets were proposed for elimination, and even the first CO2 monitor, built in 1958 on Mauna Loa, may be in danger.

We could turn this around. I spent the summer more or less as a full-time volunteer for Sun Day, a nationwide effort set for the fall equinox on September 21 to try to convince Americans that sun and wind are no longer “alternative energy” but an obvious and affordable choice. There were five hundred events—the day was marked by teach-ins, e-bike parades, Habitat for Humanity houses built with panels on the roof, solar-powered concerts. It may go global in 2026, though the US needs this effort more than any other nation; in most places the solar revolution seems to be rolling out with official support, or at least without the kind of total opposition of the Trump administration.

Or we could watch the moment slip by. One more research finding, which will make more sense now that you’ve gotten a little taste of Brannen’s superb geologic history: new data in May showed that earth’s energy imbalance—the difference between the amount of energy our planet receives from the sun and the amount it radiates outward into space—is now increasing much more quickly than the Intergovernmental Panel on Climate Change had predicted. In fact, it’s roughly doubled in recent years, partly because we’re increasing emissions but also because we’re melting the reflective ice at the poles, and perhaps reducing some of the pollution that once blocked incoming sunlight. The complex system that is our earth, a system that runs on CO2, is indeed coming unstuck, and we’re even further in the hole than we thought. When we look back on the Mesozoic, we don’t worry about what individual dinosaurs were up to; we think about the planet as a whole. And if anyone looks back at our time on earth from the same kind of distance, that’s how they’ll think about it too.