The best moment to stop was yesterday the next best moment is now.

With the current trajectory half the globe will have more than a month of deadly days. That is days where the temperature and humidity are such that humans can't sweat so they are cooked alive. Not having enough food will be another problem in 20 years because of irregular weather. We already have frost in late spring which often kills plants and in conjunction with irregular rain patterns, leads to massiv crop failures. This will only get worse.

If we don't address this quickly, swiftly we will not need fertilizer because it will not matter. Current climate change is already a mass extinction event such that it starts to rival the start of photosynthesis.

But we don't do anything so it is very likely that humanity will not survive this.