The real cost of climate change: Cambridge study warns global warming could shrink income by 24% by 2100

Global warming could reduce the average person’s income by as much as 24% by 2100, according to researchers at the University of Cambridge, a projection that underscores the broad economic risks of climate change beyond the immediate hazards of fires and floods. The study, which examines 174 countries from 2015 to 2100, uses shared socioeconomic pathways developed by the Intergovernmental Panel on Climate Change to model different warming trajectories and their economic consequences. It estimates that, under a high-emission scenario with little mitigation, global GDP per capita—the total economic output of the world divided by its population—could fall by roughly 20% to 24% by 2100 compared with a no further warming baseline. In all, the researchers say, climate change has the potential to reduce income in both rich and poor countries alike.

If temperatures rise at about 0.04°C per year with minimal adaptation or mitigation, global GDP per capita could drop about 10% to 11% by 2100. In the most extreme emissions scenario, losses could reach 20% to 24%. The study also finds that hotter, lower-income countries would face disproportionately larger losses—often 30% to 60% higher than the global average—compounding existing development gaps. Afghanistan, Bangladesh and Burkina Faso are among the examples cited as having the highest potential relative losses.

The researchers emphasize that the economic damage goes beyond the costs of rebuilding flood-damaged infrastructure or repairing drought-stricken farms. They conclude that climate change will reduce income across sectors, from transport and manufacturing to retail and services, and that the negative effects persist even when some adaptation is possible. The authors note that global climate policy matters just as much as local adaptation, and that mitigation is essential to limit long-run output losses.

The Cambridge team used Shared Socioeconomic Pathways—models that map how global development might unfold under different levels of warming—to compare projections against two baselines: a continuation of historical warming trends from 1960–2014, and a scenario with no further warming. In the first case, global GDP per capita would fall by about 10%–11% by 2100; in the no-further-warming baseline, the losses are smaller but still substantial. In the most aggressive emissions scenario with no sufficient mitigation, losses reach 20%–24% by the end of the century.

The study, published in PLOS Climate, highlights that even under modest temperature increases, the economic pain is widely distributed and that no country is immune if greenhouse gas emissions remain unchecked. The researchers argue that ongoing and ambitious action to reduce emissions, along with adaptation strategies, can significantly mitigate the losses. They also stress the Paris Agreement's goals: to keep the global temperature rise well below 2°C above pre-industrial levels and to pursue efforts to limit the increase to 1.5°C, a target that could markedly reduce the risk of severe income losses.

The authors note that future work should examine country-specific strategies for climate change mitigation and adaptation, recognizing that different regions face distinct challenges. Still, the overall message is clear: without decisive action to curb greenhouse gas emissions, long-term economic growth linked to higher incomes and living standards is at risk, and the burden would fall most heavily on those already exposed to climate hazards and lower incomes.