Is the Human Race Going Extinct?

As the media discourse around climate change continues to shift appropriately toward apocalyptic language, a recent BBC article argues that we need to begin considering the possibility of extinction.

“I know a lot of people working in climate science who say one thing in public but a very different thing in private. In confidence, they are all much more scared about the future we face, but they won’t admit that in public. I call this climate appeasement and I believe it only makes things worse. The world needs to know how bad things are going to get before we can hope to start to tackle the crisis.”

In a recent entry, I linked an article which contains this quote by climate scientist Bill McGuire. On the contrary to the protestations of so-called climate optimists (who rely on infeasible, ineffective, and politically unpopular green technology to argue for the idea that human society is capable of avoiding the worst of the environmental outcomes), the realist perspective is one of profound trepidation about the future of human civilization, if not the human race itself. Even still, rarely is the possibility of actual human extinction brought up—the danger is typically limited to our current way of life, with the assumption being that even under catastrophic conditions some form of human life will remain, however scattered and beleaguered. This final domino is now set to fall, with a paper published in PNAS calling for a more thorough investigation of species-ending, rather than just civilization-ending, outcomes. A BBC summary:

In recent years climate scientists have more often studied the impacts of warming of around 1.5C or 2C above the temperatures seen in 1850, before the onset of global industrialisation.

These studies show that keeping temperatures close to these levels this century will place heavy burdens on global economies, but they do not envisage the end of humanity. …

But this new paper says that not enough attention has been given to more extreme outcomes of climate change.

"I think it's sane risk management to think about the plausible worst-case scenarios and we do it when it comes to every other situation, we should definitely do when it comes to the fate of the planet and species," said lead author Dr Luke Kemp from the University of Cambridge.

The researchers found that estimates of the impacts of a temperature rise of 3C are under-represented compared to their likelihood.

Using climate models, the report shows that in this type of scenario, by 2070 around 2 billion people living in some of the most politically fragile areas of the world would be enduring annual average temperatures of 29C.

"Average annual temperatures of 29C currently affect around 30 million people in the Sahara and Gulf Coast," said co-author Chi Xu of Nanjing University.

"By 2070, these temperatures and the social and political consequences will directly affect two nuclear powers, and seven maximum containment laboratories housing the most dangerous pathogens. There is serious potential for disastrous knock-on effects," he said. …

"Understanding these plausible but grim scenarios is something that could galvanise both political and civil opinion," said Dr Kemp.

From the report:

There are four key reasons to be concerned over the potential of a global climate catastrophe. First, there are warnings from history. Climate change (either regional or global) has played a role in the collapse or transformation of numerous previous societies (37) and in each of the five mass extinction events in Phanerozoic Earth history (38). The current carbon pulse is occurring at an unprecedented geological speed and, by the end of the century, may surpass thresholds that triggered previous mass extinctions (39, 40). The worst-case scenarios in the IPCC report project temperatures by the 22nd century that last prevailed in the Early Eocene, reversing 50 million years of cooler climates in the space of two centuries (41).

This is particularly alarming, as human societies are locally adapted to a specific climatic niche. The rise of large-scale, urbanized agrarian societies began with the shift to the stable climate of the Holocene ∼12,000 y ago (42). Since then, human population density peaked within a narrow climatic envelope with a mean annual average temperature of ∼13 °C. Even today, the most economically productive centers of human activity are concentrated in those areas (43). The cumulative impacts of warming may overwhelm societal adaptive capacity.

The authors argue astutely that focusing more on the potentially catastrophic outcomes will spur action, not discourage it, as the mainstream climate scientists McGuire alluded to might believe, and there is no more apocalyptic a scenario to envisage than the total end of the human race. How likely is extinction, however? As long as there are sufficient numbers of humans somewhere on earth to avoid inbreeding, there is the potential for survival of the species even in the most ruined and desolate world.

It was recently revealed that “forever chemical” PFAS, which is associated with “cancer, learning and behavioural problems in children, infertility and pregnancy complications, increased cholesterol, and immune system problems,” is now being found in rainwater “everywhere on Earth”:

Even in the most remote parts of the world, the level of so-called “forever chemicals” in the atmosphere has become so high that rainwater is now “unsafe to drink” according to newly released water quality guidelines.

Forever chemicals are a group of man-made hazardous products known as PFAS, which stands for perfluoroalkyl or polyfluoroalkyl substances, some of which are linked to cancer in humans.

In recent decades they have spread globally through water courses, oceans, soils and the atmosphere and as a result, they can now be found in the rainwater and snow in even the most remote locations on Earth – from Antarctica to the Tibetan Plateau, researchers have said. …

“For example, the drinking water guideline value for one well-known substance in the PFAS class, namely the cancer-causing perfluorooctanoic acid (PFOA), has declined by 37.5 million times in the US.”

He added: “Based on the latest US guidelines for PFOA in drinking water, rainwater everywhere would be judged unsafe to drink.“

“Although in the industrial world we don’t often drink rainwater, many people around the world expect it to be safe to drink and it supplies many of our drinking water sources,” Professor Cousins said.

The birthrate is already dropping precipitously due to a number of other factors, including ubiquitous microplastics:

Then we further divided the men into two big categories. One is, were they partners of pregnant women? Were their partners pregnant, or had they fathered a child? Those are the fathers, that's the group we called fertile men. And the reason we separated them is because they cannot demonstrate the same kind of decline because if their count was sufficiently low, they would not be fathers. So just being a father selects you into a certain category as sperm count.

We also see declines in testosterone in several studies around the world. We see increases in erectile dysfunction. We see increases in rates of genital abnormalities. There is quite a lot of data on that. We see increases in testicular cancer rates. We see increases, on the female side, in diminished ovarian reserve, which means that a woman does not have as many eggs left when she gets older as she might need to conceive. An increase in miscarriage, but perhaps the most important after sperm count is fertility.

Fertility is a complicated metric, but what's usually thought of as fertility and what's published by the World Bank is the number of children that a couple has, simply the number of children born. And that number has dropped 50% between 1960 and 2018. …

Is it even realistic to believe that we can beat this? Because there is a ticking clock and although we've been aware of the climate change crisis for decades, we have done nowhere near enough to address it. We're only now becoming aware on a wide scale about this crisis. And we only have a few decades in which to address it. Is it even realistic? Is it possible that we need to go through a grieving process and recognize that our species is about to become extinct? 

Well, I don't want to minimize the seriousness of this. I think it's absolutely critical that we turn around the declines that we're seeing, but I don't think it is impossible. And the reason is that we have an option for continuing our species, which is a different kind than the options for climate change, which is that we have technology now to reproduce even in the face of very severe decline. We have all kinds of all manners of assisted reproduction that allow us to have healthy children.

The top-down political scramble to preserve the birthrate is already beginning. As I wrote previously, the growing regressive opposition to abortion and reproductive rights is predicated on such fears (in tandem with the growing racist fear of white replacement, an interrelated issue):

None of this is to absolve the US or the West in general of its role in creating the conditions of economic hardship and political repression that lead to increased childbirth and a lack of family planning in poorer nations (our relative wealth is in fact highly dependent on this predatory relationship), nor to portray them as backwards or inferior to our way of life. Indeed, treatment of women and LGBTQ+ individuals the world over is lacking even in the putatively most advanced nations with the healthiest economies, and a large contributor to this regressive tendency is the fascist need to keep the population growing to account for the demographic needs of capital (which depends on an ever-increasing growth in profits), the military, the church, as well as the maintenance of social programs and the supply of young workers to care for and support the aging population. These “collective” problems will more and more frequently win out over what will be misattributed to selfish, individualistic concerns about rights; in the same way that the war in Ukraine and high gas prices were recently deemed more important than even attempting to combat the existential threat of climate change, the Supreme Court’s revealing citation of a CDC document containing the phrase “domestic supply of infants” in its leaked Roe decision is only the beginning. As the population dwindles, the burden on women in Western nations will come to resemble that found in developing countries, and they will be asked to set aside their rights as well as their health for the good of the population. But this will not be just any population: the recent turn against abortion rights is racist in nature as well as generally regressive.

Optimists will be quick to argue that the human race will likely survive in some form (even if it consists of roving bands struggling to survive in the hell we have created for them), and has persisted through much worse in our history on this planet. But these previous near-extinctions were not on the scale of climate change, nor were they characterized by infertility-causing chemicals raining from every cloud on the planet, inescapable and corrosive. As noted in the above article, we normally do not drink rainwater, but in a climate breakdown scenario in which the world is an average of 3 or 4 degrees Celsius warmer, what remains of our civilization will find hydration wherever they can, ingesting an even greater amount of PFAS and microplastics than can now be found in precipitation (barring some ahistorical and extremely unlikely international movement to clean up these chemicals). Historic droughts are already taking place, and they will only become more frequent and extreme.

These previous brushes with extermination did not feature a reduction in human fertility across the board, which will reduce our ability to rebound as the population eventually dwindles. We will be unable to simply “reproduce through” our troubles, so thoroughly will the poisoning of our bodies become. Added to this is our preoccupation with survival: in optimistic scenarios in which the human race survives but its societies do not, oppression and struggle will be the order of the day. The optimist might posit some kind of fascist fertility program in the far future, no doubt based on the assumption that technology of that kind will survive or be improved out of necessity, even as all else has long since crumbled. The likelihood that such an authoritarian state would be concerned with selflessly ensuring the survival of the collective (or indeed anything other than the maintenance of their own power by whatever means necessary) is astronomically low. (Contrast this to our own pre-cataclysm fascist program to increase the birthrate—elite self-interest before and after society has ceased to function are two very different things).

As I previously argued in “It’s Time to Stop Procreating,” heading off a potential life does not do violence to it, because the potential life has no experiences or values to take away. There is no inherent worth to the continuation of the human race (the potential lives have no value any more than any single life which would have existed had a couple not chosen contraception), but there is inherent worth in its cessation: the ability of the natural world to begin healing itself after having been rid of the most destructive presence in this planet’s history. We should therefore not eulogize or lament our potential end, but regard it as either the natural outcome of our grossly unsustainable lifestyle or an actual boon to the rest of the creatures sharing our living space. But this value judgment is a moot point in either case: we may be soon going extinct whether we deliberately stop procreating or not, and it is time to start considering the possibility as more than remote.