That's based on the yearly temperature cycle.

那就是它是基于每年的温度循环定义的。

Our yearly temperature cycles power air and water currents that pump nutrients from deep oceans, drive winds, transport water and a million other things.

我们每年的温度循环为气流和水流提供动力，这些气流和水流从深海中吸取养分、驱动风、输送水和其他一百万种东西。