Global warming is not linear.

The difference between +1 C warming and +1.5 C warming compared with +1.5 C warming and +2 C warming might seem the same. This is because they both have temperature increases of +0.5 C. However, this is not true, as global warming is not linear; the effects accelerate and get more severe as global warming progresses. According to the Yale University Press, "the intensity of change in the climate due to warming increases with the temperature." With every increase in temperature caused by global warming, the effects are becoming more irrevisable.