489,000
Health & mortality
Heat strains the heart, kidneys and brain. Older people, infants and outdoor workers are hit first.
[ A data-driven story ]
The Warming World
Understanding why temperatures are rising, what it means for humanity, and why practical cooling solutions have never been more important.
Scroll
[ Section 01 — Global warming ]
Earth is absorbing more energy than it releases.
Greenhouse gases let sunlight in but slow infrared heat on its way out. The result is an energy imbalance of roughly 1.8 watts per square meter — small in isolation, enormous across a planet. Each additional doubling of CO₂ commits us to further warming, and the rate of that warming is increasing.
Greenhouse gases
CO₂, methane and nitrous oxide absorb outgoing infrared radiation and re-emit it back toward the surface.
Energy imbalance
More energy arrives than leaves. That surplus accumulates — over 90 % of it in the ocean.
Climate sensitivity
Doubling CO₂ warms the planet by roughly 2.5–4 °C once feedbacks such as water vapour and ice loss play out.
Accelerating warming
The decadal rate of warming has roughly doubled since the 1970s, partly as air-quality gains reduce reflective aerosols.
1880
A climate that held its shape.
For most of the industrial era, each year traced almost the same circle. Warm years and cool years balanced out around a stable mean.
1980
The circle starts to drift.
As greenhouse gases accumulate, the trace begins to spiral outward. The signal separates cleanly from natural variability.
2024
+1.55 °C — and still opening.
The warmest year in the instrumental record. The spiral is no longer wandering; it is leaving the range human civilization was built inside.
Global temperature anomaly spiral, 1880 → today (NASA GISTEMP shape)
[ Section 02 — Extreme heat ]
Warming is not felt as an average. It is felt as heat.
Heatwaves are longer, hotter and more frequent. Cities amplify them: dark roofs and roads absorb sunlight and release it through the night. Add humidity and the danger changes character — when wet-bulb temperature climbs past about 31 °C, sweat can no longer cool the body, whatever a person does.
Heat exposure
Hover or focus a region to read its heat signature.
- 2003
European heatwave
More than 70,000 excess deaths across Europe in a single summer.
- 2010
Russian heatwave
Moscow records its hottest summer in 130 years; wildfires blanket the city.
- 2015
South Asia
Heatwaves in India and Pakistan kill over 3,500 people in weeks.
- 2021
Pacific Northwest
Lytton, Canada reaches 49.6 °C — a national record — then burns down.
- 2022
United Kingdom
The UK exceeds 40 °C for the first time in recorded history.
- 2023
Global
Earth's hottest year on record at the time; ocean surface temperatures off the chart.
- 2024
Global
First calendar year measured at roughly 1.55 °C above pre-industrial levels.
31 °C
Wet-bulb danger threshold
Beyond this, evaporative cooling of the human body begins to fail.
2.4 bn
People in high heat risk
Populations regularly exposed to dangerous heat stress.
[ Section 03 — Why heat matters ]
Heat is not a discomfort. It is a systems failure.
Temperature moves through everything a society depends on: bodies, harvests, power grids, water, work and the living world.
−6 %
Agriculture
Each degree of warming cuts global wheat yields by roughly six percent, with rice and maize close behind.
$1 tn+
Infrastructure
Rails buckle, roads soften and transformers fail as design temperatures are exceeded.
×3
Electricity demand
Cooling demand is projected to triple by 2050 — often peaking exactly when grids are weakest.
2×
Wildfire risk
Hotter, drier air doubles the atmosphere's thirst, priming landscapes to burn.
1 in 4
Drought
A quarter of humanity already faces extremely high water stress in an average year.
−2.2 %
Labor productivity
Working hours lost to heat stress, equal to about 80 million full-time jobs by 2030.
84 %
Biodiversity
Share of coral reefs affected by the 2023–2025 global bleaching event.
They told us — 1985
“The Earth is warming, and we are the cause. The consequences will be felt by everyone.”
Carl Sagan
Testifying before the US Congress, Sagan explained the greenhouse effect using Venus as the cautionary case — four decades before the warming he described became measurable in every dataset.
[ Section 04 — A warming planet ]
Every system on Earth is registering the change.
Scroll to move through six planetary signals, each measured independently and each pointing the same direction.
1 / 6
Ice loss
−400 Gt / yr
Greenland and Antarctica are losing on the order of 400 billion tonnes of ice per year. Bright ice is replaced by dark ocean, which absorbs more sunlight.
[ Section 05 — The human cost ]
A statistic is a person with the details removed.
Behind every anomaly line is a classroom too hot to teach in, a ward without power, a harvest that did not come. MEER's field programmes work in exactly these places.
01
Communities
In dense settlements with metal roofs, indoor temperatures can exceed outdoor peaks by several degrees — with nowhere cooler to go.
02
Schools
Classrooms become unusable in the afternoon. Learning outcomes fall measurably on hot days, most sharply where there is no cooling.
03
Hospitals
Clinics face rising heat admissions while their own wards overheat and vaccine cold chains come under strain.
04
Food
Heat shortens grain-filling periods and spoils harvests in storage, tightening supply exactly where incomes are lowest.
05
Water
Higher evaporation drains reservoirs and wells; water-based cooling becomes impossible where it is most needed.
06
Migration
When land, work and water fail together, people move. Heat is now a recognized driver of displacement.
07
Economic cost
Heat already erases hundreds of billions of dollars in output each year through lost hours and damaged assets.
[ Section 06 — Why adaptation matters ]
Cutting emissions is essential. It is also not fast enough on its own.
Even under ambitious decarbonization, the heat already stored in the ocean and the carbon already in the air commit us to decades of further warming. Emissions cuts govern how bad it gets; adaptation governs who survives the interval.
Mitigation
Reduce what we add. Decades to take effect, indispensable regardless.
Adaptation
Reduce what harm the warming that is already locked in can do.
Resilience
Build systems — homes, clinics, farms, grids — that keep functioning through extremes.
Passive cooling
Cooling that requires no electricity, no water and no maintenance-heavy machinery.
[ Section 07 — Surface cooling ]
Cooling the Surface
A dark roof absorbs sunlight and re-emits it as heat. A highly reflective surface sends that same sunlight straight back out through the atmospheric window to space. No power, no water, no moving parts — physics doing the work.
Dark roof · 62 °CReflective roof · 34 °C
Drag to compare — measured rooftop surface temperatures, MEER field sites
Reflection
Sunlight is returned before it can become heat in the fabric of a building.
High albedo
Raising surface albedo from 0.1 to 0.8 removes hundreds of watts per square meter.
Radiative cooling
Emission in the 8–13 µm window lets surfaces shed heat directly to deep space.
Less heat accumulation
Cooler surfaces mean cooler nights — the difference between rest and heat stress.
Urban cooling
Applied across a district, reflective surfaces measurably lower ambient temperature.
Community resilience
Locally made, locally installed, locally maintained — and free to run.
[ Section 08 — MEER around the world ]
Where the work is happening.
Field deployments, measurement sites and research partnerships. Select a location to read what is underway.
ActiveResearchPlanned
Reflective canopies and cool roofs across Freetown and Port Loko, with community-led measurement and training.
[ Section 09 — Results ]
Measured, not modeled.
Every deployment is instrumented. These are the numbers the field programmes have produced so far.
−6.4 °C
Peak indoor cooling measured
20+
Communities reached
6
Research & field sites
25+
Partner organizations
30+
Scientific publications
Projected future impact
Applied at scale to roofs, shelters, water bodies and farmland across the tropics, reflective surfaces could return a measurable fraction of a watt per square meter to space while cutting local peak temperatures for hundreds of millions of people.
Read the scienceThen
Everything we measured told the same story.
Each decade shaded warmer than the one before it — oceans, land, poles, nights.
Now
The next map is still being drawn.
How dark or how bright we leave the planet's surface is one of the few levers that acts immediately.
Observed surface temperature change, 1880 → 2021
[ Where this goes next ]
The Challenge is Global. The Solutions Can Be Too.
Climate change is one of humanity's greatest challenges — but practical, scalable surface cooling can help communities adapt today while contributing to restoring Earth's energy balance tomorrow.