Climate science didn’t arrive suddenly 50 years ago. It arrived piece by piece over two centuries, beginning in 1824.

Two centuries ago, Joseph Fourier (France) first realised that Earth’s atmosphere plays an active role in regulating temperature — trapping heat and making the planet habitable. This blanket of gases is both a lifegiver and lifesaver: without it, Earth would be a frozen ball of ice, around 30°C colder than today. The greenhouse effect is not a flaw in the system; it is the reason life exists at all. That foundational insight set climate science in motion.

What followed was not a single breakthrough, but a chain of discoveries across countries and generations. Eunice Foote (US) showed that carbon dioxide (CO₂) causes heating. John Tyndall (Ireland) explained the physical mechanism, demonstrating how certain gases block outgoing heat. Svante Arrhenius (Sweden) then quantified the effect, calculating — with remarkable accuracy — how much warming a doubling of CO₂ would produce. Milutin Milanković (Serbia) mapped the slow orbital rhythms that drive natural climate change over thousands of years, clarifying why ice ages occurred — and why they cannot explain today’s rapid heating.

Observation and measurement then closed the loop. Guy Callendar (UK) detected the early human fingerprint in rising temperatures. Charles Keeling (US) provided the hard evidence: precise, continuous measurements showing atmospheric CO₂ climbing year after year. After 200 years, each step reinforced the last — a body of evidence now assessed and synthesised by the IPCC.

A natural greenhouse effect keeps the planet liveable. An enhanced greenhouse effect — driven by rapidly rising concentrations of CO₂ and other greenhouse gases like methane (CH₄) and nitrous oxide (N₂O) — is another ball game entirely.