Web-native long-form research on systemic risk, climate resilience, development finance and the energy transition.
Latest report № 2026-70 · 23 October 2026 · 22 min read
Building affordable systems that narrow global health inequalities
The life-expectancy gap between developing and high-income countries fell from 25 years in 1960 to 8.4 today, but it closed four times faster before 2000 than since, and coverage growth has halved since 2015. Sri Lanka, Thailand and Viet Nam show good health at low cost, yet in the median low-income country governments spend $7 a person on health, households pay nearly half of all costs, and an essential package would cost 11% of GDP.
By 2087, most of humanity will live in sub-Saharan Africa or South Asia. By the 2090s, the median person would live at a mean annual temperature of 26–28 °C, up from 22 °C, and the worst-off quarter beyond 28.5–29.4 °C, with one to more than two months of dangerous heat a year, in air already six times dirtier than the WHO guideline. A low-emissions, high-development path keeps unprecedented heat to 0.6 billion people instead of 3.8 billion.
By the 2090s, 4.3 to 9.3 billion people will live with frequent heat, extreme rain or long dry spells, up from 3.4 billion. The exposed population ages fast: heat exposure among people 65 and over rises nearly tenfold, to 1.3 billion. If schooling keeps rising and protecting as it has, harm falls by 70–84% in three pathways, but under SSP3 protection only holds harm level, and heat harm rises 39%.
Droughts have barely become more frequent, but they have become hot. Half of warm-season drought months in 1995–2024 were also extremely hot, up from three in ten in 1951–80 and seven in ten in 2021–24. Dry-to-wet whiplash is up 30%, and hot-dry years produce the great smoke and dust events. By the 2090s, 0.34 billion people would live with two or more compound hazards on a low-emissions path, 5.2 billion on a high one.
1.66 billion people live where two or more climate hazards overlap, but only 158 million of them also have limited means to adapt. They are concentrated in the heat-and-drought belt from Senegal to Pakistan and on cyclone coasts from Madagascar to Haiti. By 2050 that overlap nearly triples to 455 million, led by Nigeria. Halving poverty and strengthening coping would cut it to 263 million, more than lower emissions alone (356 million), though not in the most fragile states.
Multi-domain shock years rose from about 6% of countries a year before 2020 to 9% since, after 33% in 2020. The observed network has a sink: economic shocks, internet shutdowns and governance shocks raise the next year's risk of displacement or mortality shocks 2.5, 2.0 and 1.6 times. Low-income countries carry eleven times the multi-domain burden of rich ones, and twenty countries with 705 million people face a 30% or higher modelled risk of multi-domain shocks in 2026.
The world adds 1.43 billion people by 2050, 69% of them in cities and 57% in sub-Saharan Africa. People living with 30 or more days a year above a 35 °C heat index more than double, from 1.9 to 4.1 billion. Warming drives 1.74 billion of that rise and population growth 0.44 billion, and growth lands disproportionately in hot places. City dwellers in 100-year flood zones, 507 million today, are heading for 630–690 million.
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