Weather
What Is the Jet Stream, and Why It Matters
High above the clouds, a river of wind races around the planet at highway speeds and faster. It decides whether your week is stormy or calm, and whether your flight home is an hour early or late. Here is what the jet stream is.
What Is El Niño, and How Does It Work?
A patch of the Pacific warming by a degree or two can dry out Australia, soak parts of South America, and nudge up the whole planet’s temperature. That patch has a name: El Nino. Here is how it works.
What Causes Lightning, and Why Thunder Follows
A lightning bolt is hotter than the surface of the Sun and lasts a fraction of a second. It starts with something as ordinary as ice crystals bumping together inside a storm cloud. Here is how.