Climate Policy Counts Dollars and Tonnes. What if We Counted the Dead?

Climate policy has a strange way of making the human disappear. Governments talk about tonnes of CO₂. Economists talk about dollars. Corporations talk about CO₂ equivalent and offsets. Consultants talk about pathways, baselines and scenarios. International negotiators talk about degrees of warming, carbon budgets and least-cost abatement.

Of course, all of that matters. But none of it captures the thing that should matter most. A new preprint shared with me this week by Nigel Howard and his colleague Professor Peter Newman from Curtin University asks a confronting question: what if we measured climate policy not only in tonnes of CO₂, but also in lives lost?

Their report, Forecasting Lives Lost to Climate Change, proposes a framework for estimating cumulative climate-related deaths under different CO₂ emissions pathways. Its numbers are deliberately framed as precautionary scenarios, not precise predictions. And that matters. Climate mortality is incredibly difficult to model. Hunger, conflict, disasters, heat, disease, poverty, governance, trade, adaptation and technology all interact in complex ways. So no serious person can pretend that it's possible to forecast the exact human death toll of climate change over the next two centuries.

But that doesn't mean we should refuse to ask the question. Howard and Newman estimate that even rapid decarbonisation will still be associated with enormous cumulative climate-related mortality. And continued high emissions will place billions of lives at risk over coming centuries. The numbers are shocking. They are also not 100% certain. But the moral direction of the argument is very clear. Climate delay kills.

For decades, climate discussion has been dominated by the language of politics and economics. What will it cost to cut emissions? What will it cost to transition? What will it cost households? What will it cost business? What will it cost the economy? What are the CO₂ equivalent emissions reductions? etc etc. These are all legitimate questions. But they're not the only questions. And they certainly should not be the first questions. The first should be: who pays the price if we don’t act?

Too often, the answer is hidden. It's children who will inherit a hotter world. It's people in poorer countries who've contributed least to the problem. It's farmers facing crop failure. It's coastal communities facing inundation. It's elderly people dying in heatwaves. It's families displaced by fire, flood and failed harvests. It's First Nations peoples whose relationships with Country are disrupted by ecological collapse. It's future generations who don't get a vote in today’s coal, gas and oil project approvals.

That's why a “mortality cost of carbon” is such a powerful idea. It says every tonne matters. Every delay matters. Every new fossil fuel approval matters. Every corporate strategy based on expansion rather than transition matters. Every government that says it supports climate action while approving new coal and gas needs to be judged not only against its emissions targets, but against the human consequences of its choices.

Of course, the exact number of deaths attributable to climate change will always be contested. Some impacts will be direct, like heat deaths. Others will be indirect, through food insecurity, disease, conflict, migration and the breakdown of systems that keep people safe. Some deaths will be statistically visible. Others will disappear into categories like malnutrition, poverty, disaster, civil unrest or preventable disease.

But uncertainty cuts both ways. Uncertainty isn’t an excuse for inaction. It's a reason for precaution. When the possible consequences are mass human suffering and mortality, the burden of proof should not sit with those calling for urgent climate action. It should sit with those who want to keep expanding the industries causing the harm.

And this is the great moral inversion of climate politics. Fossil fuel companies and their political defenders demand certainty from scientists, while asking the rest of us to accept catastrophic risk. They say: prove exactly how bad it will be. The honest answer is: we don't know exactly.

But we know enough. We know the planet is heating. We know fossil fuels are the main cause. We know climate change is already worsening heatwaves, fires, floods, droughts and food insecurity. We know the poorest and youngest are most vulnerable. We know delay increases danger. And we know that every fraction of a degree avoided means less suffering.

That should be enough. Howard and Newman’s report should not be read as the final word on climate mortality. It's not. It's a provocation, a framework and an invitation to take the human consequences of climate change more seriously. And that's exactly why it matters. Because a society that counts dollars and CO₂-equivalent emissions, but not deaths, has already made a moral choice.