How to Predict Extreme Weather - Issue 78: Atmospheres

Thanks to advances in machine learning over the last two decades, it's no longer in question whether humans can beat computers at games like chess; we'd have about as much chance winning a bench-press contest against a forklift. But ask the current computer champion, Google's AlphaZero, for advice on chess theory, like whether a bishop or a knight is more valuable in the Ruy Lopez opening, and all you'll get is a blank stare from a blinking cursor. Theory is a human construct the algorithm has no need for. The computer knows only how to find the best move in any given position because it's trained extensively--very extensively--by practicing against itself and learning what works. Even with a lead time of 18 months, the neural network was able to see El Niño events coming.