climate change
Weather is what the sky is doing today; climate is what the weather usually does, averaged over decades. Climate change is a lasting shift in those long-run averages — temperatures, rainfall, storms, ice — across the whole planet. So a single chilly afternoon tells you nothing, just as one tall student doesn't change a school's average height. What matters is the slow, steady drift of the average itself.
Earth's climate has always wobbled naturally, but today's warming is different: it is fast, and it is mostly us. Burning coal, oil, and gas releases carbon dioxide, which thickens the blanket of greenhouse gases around the planet and traps extra heat. The result is melting glaciers, rising seas, fiercer heatwaves, and weather that keeps breaking its own records.
A common mix-up: "it was freezing last winter, so where's the warming?" But a warmer climate doesn't erase winter — it nudges the whole deck of cards, loading the odds toward hotter summers, heavier downpours, and longer droughts. A few degrees of global average sounds tiny, yet at the height of the last ice age the whole planet was only about 5 to 6 degrees colder than today — small averages, world-changing consequences.
Climate is weather averaged over about 30 years — so to spot climate change, you watch the average drift, not any single day.
People often say "global warming," but scientists prefer "climate change": the planet's average is rising, yet the knock-on effects are wider than heat alone — shifting rainfall, stronger storms, and disrupted seasons. As early as the 1850s, Eunice Foote (1856) showed that air rich in carbon dioxide traps more of the sun's heat, and John Tyndall (1859) was the first to measure how carbon dioxide and water vapor absorb infrared (heat) radiation — the mechanism behind the warming.