As COP30 opens in Belém, the region's own climate-health ledger is blunt

The 30th UN climate conference is under way in Belém do Pará, the Brazilian Amazon city the regional Lancet Countdown named as the summit's venue in its own closing argument [s1]. Days before it opened, the Countdown's Latin America arm published its 2025 assessment of what climate change is already doing to health across Latin America — a collaboration of 25 regional academic institutions and UN agencies tracking 41 indicators across 17 countries [s1]. It is the most detailed picture available of the health ledger the host region brings to the table, and it is not a flattering one.

What the heat numbers say

Average annual temperature exposure across Latin America rose from 23.3 °C in 2001–2010 to 23.8 °C in 2015–2024, reaching a record 24.3 °C in 2024 [s1]. That regional average conceals sharply uneven warming: the report records increases of about 2 °C in Bolivia, 1.7 °C in Venezuela, 1.6 °C in Mexico, 1.5 °C in Paraguay, 1.4 °C in Ecuador, 1.3 °C in Guatemala, 1.2 °C in Brazil and 1 °C in Colombia [s1].

Exposure to heatwaves has risen far faster than average temperature. Compared with a 1981–2000 baseline, infants experienced a 450% increase in heatwave exposure days and adults over 65 a 1,000% increase [s1]. For older adults the report puts the figure at 5,116% in Venezuela and 5,910% in Colombia [s1]. Heat-related mortality across the region increased by 103%, which the report translates to roughly 13,000 deaths a year, carrying an average annual monetised cost of US$855 million over 2015–2024 — a 229% rise on the previous decade [s1]. Heat-related labour losses in 2024 alone totalled US$52 billion, 12.6% more than 2023, concentrated in agriculture and construction [s1].

Drought has expanded on a similar scale. The share of Latin American land experiencing one-month meteorological drought rose from 15.8% in 1981–1990 to 59.1% in 2015–2024, a 275% increase, with Brazil, Bolivia and Mexico most affected [s1]. Extreme wildfire risk rose 10% across the region, and in Chile by 30.5 days — a 105% increase [s1]. Out-of-pocket economic losses from extreme events reached nearly US$19.2 billion in 2024, about 0.3% of regional GDP, of which less than 5% was insured [s1].

Where the risk actually falls

A study published this month in the Journal of Climate Change and Health illustrates why regional averages are the wrong unit of analysis. Argentine researchers mapped mortality risk from heat-sensitive non-communicable disease by combining national statistics, climate reanalysis and remote sensing under Argentina's own climate risk mapping methodology, layering sociodemographic, environmental, chronic-disease and lifestyle vulnerability [s2]. The resulting map shows lower risk in coastal and high-altitude north-western areas and higher risk concentrated in the centre-north of the country, arranged along a broad south-west to north-east diagonal [s2]. Age-standardised cardiovascular mortality was positively associated with the map's overall heatwave risk estimate (RR 1.68, p < 0.001) [s2].

That is a single country and a single disease group, and the underlying heatwave data run from 2006 to 2010 [s2]. But it demonstrates the kind of sub-national resolution the regional report says is largely missing from planning.

The adaptation gap

On governance, the Countdown's regional numbers are stark. Fewer than half of the region's countries — 41.2% — have publicly reported completing a vulnerability and adaptation assessment since 2020, and only nine countries (53%) have developed a national health adaptation plan [s1]. Mentions of health in Latin American countries' UN General Assembly addresses fell from a peak of 10 countries in 2010 to three — Bolivia, Brazil and Chile — in 2024 [s1].

Money follows the same pattern. Bilateral donors committed US$197 million to health adaptation projects in 2024, but 68% went to Brazil alone [s1]. Of US$3.4 billion approved by the Green Climate Fund since 2017 for projects with any health dimension, only US$77.7 million — 2.3% — targets direct health adaptation [s1].

There is at least one clear counterexample of what works. Countries with climate-informed health early warning systems recorded a 92.5% decline in mortality from floods and storms [s1]. Improvements in basic water and sanitation drove a nearly 60% reduction in the region's Mosquito Risk Index since 2000 [s1]. These are the report's strongest arguments that adaptation is not theoretical.

Air, energy and the fossil fuel line

The energy indicators are the section most directly in tension with the summit's framing. Latin America's net carbon price is negative: fossil fuel subsidies across the region total US$38.6 billion, outweighing carbon pricing revenues by nearly fifty to one [s1]. The low-carbon share of the region's electricity mix fell from 67.6% to 58.9%, even as solar and wind grew from 2.7% to 11.8%; coal's share nearly doubled, from 2.6% to 5.2% [s1]. Road transport remains 96.7% fossil-fuelled [s1].

The health cost of that shows up in air quality. Ambient fine particulate matter from coal and gas is held responsible for 360,000 premature deaths among working-age people, and PM2.5 from biomass for an estimated 140,000 deaths in 2018–2022, 17,000 more than in 2007–2011 [s1]. Indoor PM2.5 from solid cooking and heating fuels averaged 245 µg/m³ in 2022 — 314 µg/m³ in rural households against 145 µg/m³ in urban ones [s1]. Monetised years of life lost to PM2.5 across 11 countries came to US$160 billion, about 2.8% of their combined GDP [s1].

What this does and doesn't establish

These are indicators, not experiments. Attributing a given death to heat rests on modelled exposure–response relationships, and the report's own methods note refinements and six new indicators this cycle, which means year-on-year comparisons are not always like for like [s1]. The Argentine risk map is an association between a composite index and mortality rates, not a causal estimate for any individual [s2].

What the two documents share is a direction. Exposure is rising faster than the institutional response, the money that exists is concentrated in one country, and the indicators most responsive to policy — early warning systems, water and sanitation — are the ones showing improvement. The report's own framing for the summit is that the region should push health-prioritised adaptation and mitigation with health co-benefits [s1]. Whether Belém produces anything measurable against these indicators is the thing to watch when the next edition lands.

Sources

• The 2025 Lancet Countdown Latin America report: moving from promises to equitable climate action for a prosperous future — The Lancet Regional Health - Americas, 2025-10-29
• Comprehensive risk mapping for heatwave-sensitive chronic diseases mortality in Argentina: An approximation based on cardiovascular diseases — The Journal of Climate Change and Health, 2025-11-01