Our Coming Die-Off

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In the next few decades, our human species could suffer a massive die-off. Hundreds of millions of us could die miserably before our times. Billions might.

There’s not much we can do now to prevent the catastrophe. Most of it is already baked in (pun intended). All we can do is mitigate it.

To see why, watch two short YouTube videos. The first is this one, of David Attenborough addressing the COP26 opening session. Pay special attention to the ever-rising CO₂ numbers. Then don’t miss the graph of 10,000-plus years of stable climate—during which our species, having completed its long evolution, civilized itself. Finally, note the horrifying spike at the modern end.

For the final touch, watch this eloquent plea by the Prime Minister of Barbados, Mia Mottley, speaking for the people of the so-called “Third World.” They are already starting to die off, as in Haiti and several parts of Africa today. The “homeless, tempest-tost” masses now storming the southern borders of the US and EU are just the vanguard of far larger, more desperate masses to come.

The cause of the coming die-off is something familiar to engineers and scientists: positive feedback. As its ice melts, the Earth gets less reflective and absorbs more heat from the Sun. As the warming sky fills with water vapor, it, too, acts like a blanket, and solar panels and windmills generate power less efficiently. As permafrost melts, the vast reaches of northern Canada and Siberia belch out methane—a greenhouse gas far more potent than CO₂—in unknown but increasingly massive quantities. Ditto for disassociating methane hydrates in the deep ocean, which break apart as the oceans warm.

More heat, then repeat. The first two causes of heating feedback are well modeled. The last two are not. They are big wild cards, and they may become the dominant sources of positive feedback.

Scientists can’t and haven’t studied them well because they are occurring in sparsely populated and inaccessible areas. But scientists know their general effects: they accelerate global warming dramatically. (Melting permafrost is better established: visitors and scientists alike can see and measure permafrost melting and methane bubbling out of nearby lakes and ponds. The dissociation of deep-sea methane hydrates relies on indirect evidence, including laboratory experiments.)

The point of all this is subtle but profound. As these feedback mechanisms gather steam, the source of global heating is no longer just the steady drip, drip, drip of CO₂ from our power plants and exhaust pipes. Some of the heating has already become not just self-sustaining, but self-multiplying. Even if we stopped burning fossil fuels tomorrow, or if a new pandemic killed us all off, heating would continue, due to the four feedback mechanisms described above. And recall that methane—the product of the last two—has up to 80 times the heating power of CO₂.

That’s why the last ten years have seemed so decisive, even to a casual observer. Relative to the pre-industrial baseline of about 280 ppm, our present CO₂ level of 415 ppm is nearly 50% higher. But the increase didn’t happen in just the last ten years.

In that short time, the level rose only about 25 ppm, less than 10%. Yet you don’t need a supercomputer model to tell that something in our climate and weather has changed dramatically in the last ten years. That’s the effect of positive feedback: we’ve reached some sort of tipping point from which recovery may be impossible.

How hot will we get? There’s no clear stopping point for climate feedback, like the maximum sound output of an amplifier whose speakers are too close to the microphone. Venus’ atmosphere has far more CO₂ than Earth’s, and it has an average surface temperature of 847°F, higher than the melting point of lead. No mammal could live there; in fact, no multi-celled organism we know of could survive there.

Of course Venus is also much closer to the Sun and has more volcanic activity. But you get the point. There’s no intrinsic limit on how hot the Sun’s radiation can make a planet. For Earth, there is only the next higher equilibrium state based on its particular atmosphere, seas, geography, composition, and biosphere. No one has any idea now what its next equilibrium state will be like, after we’ve disturbed the one we’ve been living with for 10,000 years.

So what’s the upshot? Positive feedback is causing global warming to accelerate more rapidly than anyone expected—even the most “alarmist” scientists—as few as ten years ago. And positive feedback, primarily through the release of methane, has made the heating process self-sustaining, at least in part, for the foreseeable future.

You don’t have to be a scientist yourself to understand. You just have to have a good memory. For decades, scientists have been predicting catastrophe by the end of this century. But it’s already happening now. Wildfires have devastated large stretches of California (even Northern California) and Australia. Repeated, unprecedented hurricanes have hit our Gulf Coast and our Atlantic Coast, not to mention the Philippines. Little, presumably safe mountain villages in Germany and Belgium have been all but washed away by unprecedented floods. This year, parts of Oregon, Washington and Northern Siberia have experienced 100°F-plus temperatures never before recorded. And the Great, Desperate Migration from overheated, drought-stricken Africa (including parts of the Middle East) has caused an ongoing immigration crisis in the EU.

Whether you are a scientist or an ordinary citizen, be honest with yourself. Ten years ago, did you foresee any of this, let alone all of it? Who predicted that climate change would hit us so hard so soon?

No one did. Scientists did least of all, not on this time scale. They can’t predict what they can’t model, and they can’t study stuff happening in the melting Arctic tundra very well, or on the deep-sea bottom much at all. Add the relentless social and political pressure of business people and politicians with an agenda to minimize the danger, and you have a recipe for perpetual scientific understatement.

Anyway, one thing is clear. All the disasters to this date are just the beginning of anthropogenic climate destabilization.

Much heating is now baked in, with CO₂ levels already unprecedented during the entire span of human civilization. Like a blanket, greenhouse gases store the Sun’s heat relentlessly; and the Sun isn’t going out any time soon, else we would all freeze and die from cold. So all we can do now, with the greatest collective effort we can muster, is slow down the acceleration of heating. Stopping or reversing it, at least in this century, will be virtually impossible, short of something like a deliberately induced “nuclear winter.”

Why is reversing the heating so far physically impossible? It takes many decades to absorb CO₂, let alone methane, from the atmosphere, whether in the oceans or by growing trees. Meanwhile, all four positive-feedback processes are continuing without regard to human activity. As for trees, the Brazilians under Jair Bolsonaro are busy cutting and burning them down as fast as possible in the Amazon Jungle, our planet’s largest remaining forest “lungs.” Despite all our species’ so-far feeble effort, our total greenhouse-gas emissions currently are continuing to increase.

As if all this were not bad enough, there is yet another positive feedback loop: a social and political one. The only way that we humans can fight the climate destabilization we have caused is by working hard together. Fighting it will take decisive, global, species-wide action. It will require the strongest, widest, most sustained cooperation that our fractious and contentious species has ever attempted.

Yet at the moment, we are “cooperating” worse than a herd of cats. Leaders of China, Russia and Brazil, whose nations are collectively responsible for over half of today’s global greenhouse-gas pollution, simply didn’t show up at COP26. Joe Manchin, a single senator, has hobbled the United States’ attempt at “leadership.” He appears, pathetically and catastrophically, to be protecting his tiny state’s dying coal industry and his own personal investment in it.

One of the saddest things to watch at COP26’s opening session was British PM Boris Johnson’s demeanor as Attenborough spoke. Johnson represents the island nation that produced three of the four greatest thinkers in human history: Isaac Newton, Adam Smith, and Charles Darwin (the fourth being Albert Einstein).

Yet there he was, looking downcast like a scolded school child. Not only was his much-vaunted Brexit too little and too late to repair the fragility of a senselessly globalized and now brittle economy, shattering under the pressure of Covid-19 even as you read this. It was also a step in the wrong direction, making climate cooperation just a bit harder.

So don’t expect much from COP26. It was doomed before it even started, doomed by the selfishness of our species. It was doomed by the absolute predominance of unrestrained capitalism as a global economic religion. It was doomed by the rejection of any concerted planning (aka “industrial policy”) almost everywhere but in China and Germany. It was doomed by the weakness of traditional religions, such as Pope Francis’, which teach selflessness and cooperation but are fading under the influence of internal problems like pedophilia and a species-wide stampede toward short-term greed.

Will our species ever undertake the tasks that it must do collectively, not to ward off the worst—that is inevitably coming—but to mitigate it? The hour is late, and the prognosis is sober. The task won’t get easier as crops begin to fail, large populations start to migrate to safety even within the “First World,” desperate hordes from without it become massive waves of refugees, and dominant powers like China seize the turmoil as a chance to make military plays. Just don’t forget that little, fragile Taiwan is where many of the world’s computer chips are made, and we will need those chips for any technological solution.

Besides throwing a good party, perhaps the thing we humans do best is congratulate ourselves. We once thought we were the center of the Universe and our small blue planet its focal point, around which all else revolved.

Now we know we are but one ever-vulnerable species, dominating a small planet in a solar system on the outer edge of a spiral arm of a rather small galaxy. Our once-comfortable civilization has pretty much stopped our biological evolution, which anyway takes far longer than our recorded history to produce recognizable change. So we are unprepared biologically for the next climate equilibrium, which we have already set in motion. Perhaps the best we can do to save ourselves is to move toward the poles.

Maybe we should downgrade our self-awarded designation from Homo sapiens to Homo ordinarius. For when it comes to our self-created catastrophe, we are on track to repeat the suffering of every other species facing loss of food and a livable habit: migration, conflict, starvation, and a big die-off. Let’s hope that nuclear weapons won’t play a leading role in our partial or total self-extinction.

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