Within the lifetime of anyone born at the start of the Baby Boom, the human population has tripled. Has this resulted in a human endeavor three times better — or one-third as capable of surviving? In the 1960s, humans took about three-quarters of what the planet could regenerate annually. By 2016 this rose to 170 percent, meaning that the planet cannot keep up with human demand, and we are running the world down.

“In other words,” say 17 of the world’s leading ecologists in a stark new perspective on our place in life and time, “humanity is running an ecological Ponzi scheme in which society robs nature and future generations to pay for boosting incomes in the short term.” Their starkly titled article, “Underestimating the Challenges of Avoiding a Ghastly Future,” reads less as an argument than as a rain of asteroids encountered in the course of flying blind on a lethal trajectory. The authors’ stated goal is not to dispirit readers. “Ours is not a call to surrender,” they write, “we aim to provide leaders with a realistic ‘cold shower’ of the state of the planet that is essential for planning to avoid a ghastly future.”

Put on your shower cap and step into the cold. Humans have altered about 70 percent of Earth’s land surface and ocean. Wetlands have lost 85 percent of their natural area; kelp forests have lost 40 percent; seagrass meadows are disappearing at 1 percent per year; the ocean’s large predatory fish are two-thirds gone; coral reefs have lost half their living mass. Agriculture has halved the weight of living vegetation on land, driving a diversity loss of 20 percent; 40 percent of extant plants are currently endangered. Farmed animals and humans now constitute 96 percent of all land vertebrates; only around 5 percent are wild, free-living animals. The world’s wild populations of birds, mammals, fishes, reptiles, and amphibians have declined by an average of nearly 70 percent in just the last 50 years, a breathtaking plummet. More than 700 vertebrate species have gone extinct over the last 500 years, an extinction rate 15 times the natural rate. Around a million species are now threatened with total extinction. These disruptions and declines have caused the deterioration of soil, air, and water quality; pollination; carbon sequestration; and human health. Other things have increased: floods, fires, the number of malnourished people, plastic pollution, general toxification, and infectious epidemics.

Referring to the loss of living diversity and abundance, the authors note: “The mainstream is having difficulty grasping the magnitude of this loss, despite the steady erosion of the fabric of human civilization.” But I think the problem is that the fabric of human civilization has been built and fueled precisely by causing erosion of the living world. The pain of other living things is seldom humanly felt, their interests seldom considered, their intrinsic values discounted. (I am still asked “why we should care” about whether even iconic creatures such as right whales, for example, vanish forever.)

Worth noting is that the authors are overwhelmingly ecologists. As am I. This may account for their perceiving a grim future versus the rosy future offered by techno-optimists. Ecologists understand the world as interdependent relationships among diverse living and non-living systems. Ecologists examine feedbacks that result from, and make possible, the continuity and wondrous proliferation of life. Optimists tend to point to key human social trends such as rates of hunger and poverty. (The number of malnourished declined from 1 billion in 1990 to 800 million in 2017, a rate some well-nourished optimists feel good about. And while poverty rates also declined, population growth resulted in more extremely poor people.)

In my view and the view of others whom we might call techno-skeptics, technology alone won’t solve the accelerating collision. Any social system, any technology, delivers on its values. New technology that serves the same values that have caused the current array of problems will likely accelerate those problems. (Robots that put people out of work come to mind.) At core, optimists and ecologists are not having the same conversation. Optimists are upbeat about the way human things have been going. Ecologists see existential threats in the relational overshoots of the human footprint, strained social systems, climate feedbacks, and the extinction crisis. Ecologists understand that building an ever-larger human enterprise has resulted from putting more of the world through a macerator at the expense of the rest of life on Earth and generations unborn. On a planet that is finite, such an enterprise faces inevitable limits. We are slamming the guardrails.

The point of seeing existential threats is not to face a doomsday future but to avert one. When the oil light comes on or the warning bells are insistent because you’ve fallen asleep at the wheel, it is safest to pull off the road you are hurtling along and assess your situation.

The authors of “Avoiding a Ghastly Future” highlight several main implications of our road too heavily travelled. One, current trends put the future on track to be much worse than generally appreciated. The scale of existential threats to humanity and other living things is so great as to be nearly incomprehensible. Second, humanity’s existing governments and leaders are not up to what’s needed. And mounting stresses such as managing climate refugees will perversely drive politics toward a diminishing capacity to recognize and deal with problems — as has become stunningly evident. Refugees fleeing climate-related famines or sea-level rise — in places like Afghanistan, Samoa, the Philippines, and the U.S. Gulf Coast, for example — strain politics and response systems, creating crises that dash the likelihood of diffusing underlying crisis-causing problems.

The most fundamental driver of putting more material into our enterprise, human population growth, is on track to continue at least through this century. But population growth and its effects are uneven around the globe. Some nations are stable or even declining slightly in numbers; some consume vastly less per person. But even the poorest, lightest-living people need land, food, and water, and the results are stark to anyone who has known and loved a place over several decades.

Just as population growth and consumption are not uniform, neither is the misery created. An estimated three-quarters of a billion people are slowly starving and 1 to 2 billion don’t get enough food to fully function as human beings. Population growth causes crowding, joblessness, friction, and conflict. Managing the heat of friction as population grows and the economy is under pressure to keep up makes it more difficult to cool it. It becomes less likely that leaders will recognize cooling, rather than fueling, as the more urgent need. This is evident as near-universal policies focus on getting “more” — more food for more people, for instance, rather than easing the crises by policies incentivizing population flattening and de-growth.

But most economists and politicians and their policies catastrophically confuse growth and improvement as synonymous. The fundamental difference is that growth means getting larger by pushing more material into the system. Improvement means more effective outcomes. We all experienced a period when our bodies’ program was growth. When growth stopped, our focus could become improvement. Improved health care, education, and compassion do not require growth as a necessary condition. It seems, conversely, that a focus on growth often obstructs improvement.

Meanwhile, global economic growth will continue through this century, meaning that aggregate consumption will increase in coming decades. Fossil fuels presently enable most consumption; they’re the source of 85 percent of commercial energy, 65 percent of fibers, and most plastics. Agriculture also depends on fossil energy. Consequent to this burning, climate warming has matched or exceeded prior scientific predictions, and the most recent models predict more warming than did earlier models.

The loss of living things may mean little to most people, but climate changes are more obvious and more directly damaging to human life and investments. Perversely, atmospheric warming threatens to lower regional agricultural yields, increase mortality and morbidity, and even affect human cognitive functioning. The intensifying storms, coastal wash-overs, and fires of late might reasonably cause us pause. Such existential threats would seem likely to command the full attention of governments.

But national and international responses have been wholly inadequate. Nations are not meeting goals set under the Paris climate accord, the Convention on Biological Diversity, and the UN Sustainable Development Program, due mainly to the lack of governmental commitment to their success. The authors say that without fulfilling existing pledges — not to mention additional measures required — “Earth’s temperature will be catastrophic for biodiversity and humanity.”

Worsening trends should prompt positive responses from a rational being. The opposite is occurring. Worsening trends exacerbate social pathologies. Politics works short-term; changes necessary for a livable future are politically risky. Meanwhile politicians seldom get blamed for incurring the real risks and mounting costs behind catastrophic floods and fires. Conflicts, refugees, and wars are seldom understood as being partly (sometimes wholly) attributable to environmental changes. Those problems increase discord. Crises fuel the rise of extreme ideologies, terrorism, and autocratic heads of state (the U.S., Brazil, and Russia are among the examples). All this makes less likely the cooperation necessary to ease root causes, creating a perverse cycle of ecological decline, rising risks, catastrophic damages, social inequality, and dysfunctional responses.

Environmentalism, rather than being regarded as a non-partisan endeavor to bring humanity together in a quest for self-preservation and planetary stabilization — as in the 1970s — is now often seen as a political ideology. As the authors of “Avoiding a Ghastly Future” point out, the Green New Deal in the U.S. has been a flashpoint for political polarization. Indeed, environmental groups are frequently labeled “terrorists.” To get a quick idea of how dangerous it has become to protect land, wild things, and wild places, search the Web for: environmentalists murdered (over 200 killings in 2019).

Big-picture solutions exist, including fundamentally tweaking global capitalism by including costs of pollution in the production of carbon and chemicals, for instance; rapidly attenuating fossil-fuel use; and ditching the delusional ideology of perpetual growth. Even the most fundamental issue, human numbers, could largely solve itself as social progress continues alleviating what might be the world’s most widespread inequity — suppression of women.

What the solution-assigned institutions have lacked at the helm, however, is a species capable of the foresight, cooperation, and compassion that would avoid sinking the planetary ark. Whether humans could become that species remains to be seen. We are manifestly capable of creating planetary problems. We are not proving capable of fixing them.

A reckoning is coming. The authors warn that the only choice is between exiting the overshoot by design or by disaster. If we don’t get it, it will get us. There is no third way out of inevitable contractions in economic growth and human expansion.

On the positive side, many examples exist of successful interventions at smaller scales, such as the cleaner skies and waters resulting from laws and policies in the U.S. and elsewhere and the successes of the U.S. Endangered Species Act. But the authors contend that globally, only colossal international approaches to the colossal problems could let nations chart “a less-ravaged future.”

The point of “Avoiding a Ghastly Future” is that we all must recognize the enormity of these problems. But the authors believe that reality can be faced without sowing “disproportionate” fear and despair. They say the necessary choices will entail “difficult conversations about population growth” and “the necessity of dwindling but more equitable standards of living.”

About this last conclusion, I don’t fully agree that it has to be like that. I hope the optimism bias that they warn of isn’t getting in my way. More equitable standards of living mean not dwindling standards for all, but rather, for many people, bigger and better lives than current inequities force billions to endure. Women who attain empowerment tend to seek smaller families simply as a matter of personal choice. So, what is difficult for some should hold great attraction for many now deprived of dignity, education, and equality.

In my view, if there is one silver bullet that can quell the multi-headed dragon of our looming future, that bullet is full citizenship for women — legally, financially, and culturally. Where women can enter higher education, secure bank loans, inherit wealth, own businesses, and ascend to high positions in business and government, population growth has largely tended to slow, as living becomes more equitable. Women more in control of their decisions and lives choose birth spacing and smaller family size. No discussion is necessary about the need to reckon with global population; personal decision-making suffices. The secret of those who attain more control of their own lives is that smaller families give people larger lives. The biggest slices of pie get cut at the least crowded tables.

The cold shower outlined in “Avoiding a Ghastly Future” should motivate scientists to speak out strongly and should motivate investors and policymakers to envision and implement the many comprehensive solutions that have been charted. It’s not really a matter of “avoiding” a ghastly future; it’s whether we decide to create one. If we decide not to, we have our work — and our moral and ethical reflections — cut out for us.