Shoichiro Kido

A translator in a conference room hears not only the words but also the echo of previous phrases still bouncing around the ceiling. If they get distracted by every reverberation, an hour of conversation turns into two. Similarly, a complex system, whether an ocean or a power grid, receives random jolts that do not vanish instantly but drag behind them a tail of memory.

In winter, one part of town gets three times as much snow as the neighborhood next door. One year is a scorcher, the next is a cold snap. That's the whims of weather. But over decades, a different, slow shift emerges: winters, on average, get milder. Telling the two apart is the central challenge for climate scientists.