When they start to seize up a lot of non-linear effects-processes in which small causes have disproportionate effects-come into play, making it much harder to see what is going to happen next.

当气流开始运转不畅时，很多非线性效应——在这些效应过程中，细微因素能产生不相称的影响- - -发挥作用，进而更难以预测接下来会发生何事。