So in general we would consider this to be an irreversible reaction, even though it is.

所以一般来说，我们会认为这是一个不可逆的反应，即使它是。

The popular idea of cutting our emissions in half in 10 years only gives us a 50 % chance of staying below 1.5 degrees, and the risk of setting off irreversible chain reactions beyond human control.

十年内减排半数尾气这一普遍的想法只能使全球温度升高保持在1.5度范围内的可能性达到50%，而且不可逆的连锁反应一旦引起，人类根本手足无措。