The unforgiven generations

The generations currently in their third or fourth act—Baby Boomers and Gen X, born roughly 1946 to 1980—have contributed a dizzying mix of positives and negatives to the world. We created the internet and personal computing; remade arts and entertainment in good and terrible ways; spurred incredible economic growth, then killed the middle class; opened up greater access to higher ed, then saddled a generation with crushing debt. We were the ones who put cultural diversity on the front burner, then said "just kidding" in the voting booth. We changed the essence of parenting and childhood for better and worse. We brought torture and imprisonment without charge back into vogue. We stopped a pandemic in record time with a vaccine that we then refused to take. We elected a gifted president who surrounded himself with talent and intelligence, and we elected an autocratic narcissist whose damage has only begun to play out.

None of it will be remembered for long.

Decades from now, even centuries, the adults of the past 50 years will be associated with one thing only: climate inaction. And we will not be forgiven.

Leaving our children, and theirs, and theirs, a far worse world

We aren't the first cohort to badly mis-play the hand we were dealt. The generations of the late Roman Republic in the 1st century BCE were riven by political corruption and power struggles that led to the fall of the Republic and a slide into imperial autocracy. An excessive accumulation of wealth by aristocrats and neglect of everyone else led to the French Revolution, then Napoleon and a period of continuous war. The entrenchment of US slavery prior to the Civil War. The grotesque exploitation of workers, child labor, and environmental degradation in the early Industrial Revolution. The interwar political leadership of Germany that led to Naziism. All terrible.

But we will be remembered with greater contempt than any of these.

The reason is this: No other fumbling of the ball will pass on as much daily human misery to the future as our failure to respond to the climate crisis when we still could. No one feels the negative consequences of the demise of Res Publica or the Ancien Régime every morning. But the consequences of a climate that has spun irretrievably out of control will be woven deep into every part of the human experience for centuries to come.

The (relatively) blameless generations

The destruction of Earth's biosphere can be laid firmly at the feet of the Industrial Revolution. Every generation that lived and worked and made decisions in developed countries during that period—decisions often driven by greed, selfishness, and a lust for power—contributed to the disaster that is now our inescapable reality and our legacy. But most of those generations toiled and innovated and hoarded and spewed without knowing the consequences of their actions.

The atmosphere was still seen as an inexhaustible sink. I remember being floored by Carl Sagan's description of the atmosphere's thickness relative to the earth being the same as a coat of shellac on a classroom globe. That was in 1995.

Not that there weren't early warnings. Joseph Fourier first proposed the concept of what would eventually be called the greenhouse effect in 1824. American scientist Eunice Foote first described the specific propensity of atmospheric carbon dioxide to lead to atmospheric warming in 1856. As early as 1896, scientists were drawing a line between burning fossil fuels and increasing global temperatures. In 1957, we get the first regular atmospheric CO2 measurements and the Keeling curve charting their steady rise.

But these were isolated scientific findings, shared in conferences and in journals with print runs in the low hundreds.

Those who knew and did nothing

By the 1970s, the growing awareness of a climate crisis pushed into international public policy, first with the UN Conference on the Human Environment (1972), then the World Climate Conference in Geneva (1979) declaring climate change to be a global issue that required international cooperation. And then, in 1988, the Intergovernmental Panel on Climate Change (IPCC) was established to assess climate science and advise governments.

If we need to identify a moment at which inaction could no longer be excused, the World Climate Conference in 1979 will serve. Boomers were young adults in their 20s and 30s. The establishment of Earth Day in 1970 had launched the environmental movement, followed by the (US) National Environmental Policy Act (1970) requiring environmental impact assessments for federal projects, the creation of the EPA, the Clean Water Act, and the discovery (and rapid mitigation) of ozone layer depletion.

Awareness was high. The window for informed action was open.

Earlier generations had an opportunity to change their behavior but no knowledge of the need to do so. Later generations—arguably Gen Z, Gen Alpha, and onward—will have knowledge of the crisis and its cause but an expired window of opportunity. They will be left only with the consequences of the inaction of those who knew and did nothing.

As of 1979, by most estimates, we had about 45 years to turn things around. If we failed to act within that time frame, the tipping point would be unavoidable, the worst effects of climate change inevitable.

That 45-year timeline expired in 2024, a year that ended three weeks ago.

Instead of taking meaningful action to reduce emissions, global carbon dioxide emissions from fossil fuels and industry nearly doubled between 1979 and 2024, from approximately 19.5 billion metric tons to 37.01 billion metric tons per year.

Only poor excuses remain

There are so many excuses and explanations for pressing the accelerator as our planet approached the cliff: The tragedy of the commons (in which individuals or nations acting in their own self-interest overexploit or destroy a shared resource, to the detriment of everyone including themselves), ignorant denial ("temperatures have always gone up and down"), concerns about job losses, simple inconvenience and short-term greed, the relative abstraction of it all, and the slowness of the pot's boiling, with the most serious consequences delayed.

The generations facing first heatwaves, droughts, and powerful storms, then dramatically rising sea levels, devastating floods, and intense agricultural stress, then Amazon die-back, the displacement of millions, the collapse of polar ice sheets, ecosystem failures, mass extinctions, food and water insecurity, and a decimated global economy—all now expected before 2100—those people will certainly find it hard to understand our far-reaching selfishness, and even harder to forgive.