The twenty-first century is being shaped by three pressures acting on the same people at the same time: a warming climate, a polluted environment, and a more unstable political and economic order. Each is large on its own — 2025 was the second or third warmest year on record, air pollution contributed to 7.9 million deaths in 2023, and 2025 saw 65 conflicts involving states, the most since records began — but what distinguishes the present is their interaction. A heatwave becomes a harvest failure, a price spike, a fiscal squeeze and a displacement crisis; an energy-supply shock becomes a pollution crisis as households return to dirtier fuels. Repeated shocks can ratchet systems downward, because each one erodes the buffers needed to absorb the next.
This report argues that the variable that most reliably separates societies damaged by compound stress from those that come through it intact is adaptive capacity: the standing ability to anticipate, absorb, adapt to and, where necessary, transform in the face of shocks. It organises capacity into a five-layer Capacity Stack — sense and anticipate; buffer; distribute and diversify; protect people; and govern, finance and learn — and shows how each layer pays off against all three stressors. The report quantifies the gaps: international public adaptation finance of about US$26 billion in 2023 against estimated needs of US$310–365 billion a year by 2035; US$921 billion of net interest paid by developing countries in 2024; and a pollution burden that exceeds the measured toll of heat, disasters and conflict.
Two arguments distinguish the analysis. First, pollution control and clean energy are treated as adaptation investments, not only as mitigation: Beijing’s two-thirds cut in particulate pollution, the global phase-out of leaded petrol and the Montreal Protocol show that exposure can be cut fast, and the same measures strengthen health, productivity, fiscal buffers and energy security. Second, capacity must be designed for instability as well as weather, which favours reduced dependence, modularity, flexible finance and local control over attempts to forecast political shocks. Seven case studies — Bangladesh, Ahmedabad, Beijing, the Netherlands, Singapore, Ethiopia and Barbados — show that capacity is buildable at many income levels where institutions, budgets and feedback loops are sustained.
The report concludes with actor-specific strategies, a three-phase roadmap to 2050, a capacity scorecard, an analysis of the ways adaptation can fail, and ten commitments. Its central finding is that thriving under compound stress is a matter of design and timing: capacity built early, for more than one stress at a time, is cheaper, more effective and more equitable than capacity improvised after the damage is done.