■ Domain 02 · Poverty
Poverty is the exposure multiplier. It turns every other stressor lethal.
The same heat wave, the same polluted air, and the same failed water supply produce radically different outcomes at different incomes. Poverty is not one of the four exposures; it is the coefficient on the other three.
DATA WINDOW 2000–2100 · BASELINE 2025 · WORLD BANK · ILO · IPCC AR6
The baseline
The century opened with the largest poverty reduction in human history — and a fragile floor
In 2000, 1.75 billion people — 29 percent of humanity — lived below the international extreme-poverty line. By 2024 the count fell to roughly 700 million. No other exposure in this atlas improved that fast.
The engine was convergence. East Asia's manufacturing boom lifted hundreds of millions above the line; South Asia followed; Africa's reduction started later and runs slower. The floor that remains is harder. The last 700 million live disproportionately in fragile states, in conflict zones, and in the districts most exposed to heat, drought, and flood.
That floor is not stable. Climate damage now works against the poverty engine — destroying assets, cutting agricultural income, and pushing households that had escaped back below the line. The World Bank's own accounting puts tens of millions of additional people into poverty under current warming by 2030.
Poverty reduction is the cheapest adaptation policy in the polycrisis. Every percentage point of poverty removed is a percentage point of the population moved out of the overlap — without touching a single climate variable.
The overlap
The poor do not merely face more climate risk — they live inside it
Exposure maps and poverty maps align almost perfectly. The districts with the highest heat, the worst air, and the most fragile water are the districts where the $2.15 line runs through the middle of town.
The overlap is structural, not accidental. Land is cheapest where hazards are highest — floodplains, steep slopes, unserviced urban fringes. Housing quality, drainage, cooling, and insurance all cost money the poor do not have. The result is a near-mechanical rule: the lower the income, the higher the share of income exposed to climate shocks.
Hazard discount
Land and housing are cheapest where floods, heat, and pollution are worst. The poor buy exposure at a discount and pay for it in health and lost assets.
No buffer
A climate shock at $2.15 a day consumes the whole margin. Savings, insurance, and credit — the standard shock absorbers — are precisely what extreme poverty lacks.
Reversible progress
Households that crossed the poverty line recently sit just above it. One failed harvest or one heat-disrupted work season pushes them back below.
The mechanism
Heat taxes poor workers before it kills them
The ILO estimates heat stress could cost 2.2 percent of global working hours by 2030 — the equivalent of roughly 80 million full-time jobs. The loss concentrates in agriculture and construction, and inside those sectors it concentrates in low-income countries.
The physiology is unforgiving. A laborer paid by the day either works slower in the heat, stops early, or works through it and risks heat illness. All three cut income. The same worker has no cooled home to recover in and no savings to bridge the lost day. Heat thus operates as a regressive tax: the richest households barely feel it as a productivity number; the poorest feel it as food not bought and school fees not paid.
That is why the heat page and this page must be read together. Heat exposure determines the dose; poverty determines the damage. Separating them produces forecasts that are far too optimistic about the cost of warming.
Do not model poverty and heat as separate damages. Model heat as a wage cut applied first to the people with the smallest wage — then compound the rest of the polycrisis on top.
Next: the stressor that taxes the poor first
The heat page quantifies the dose — from global temperature pathways to wet-bulb threshold days.