Corresponding likelihood of staying below 1.5 C, 1.6 C, 1.8 C and 2.0 C at peak according to Table 7 in Forster et al. 10 . Likelihoods all assume the median of non-CO 2 contribution towards peak warming. In a , full symbols in the middle show the default assumption of combined differentiation of carbon prices and emissions-reduction quantities, whereas the four options on the left with open points show the results assuming no improvement of institutional capacity over time. The open points on the right side show the more optimistic assumption of only differentiated carbon prices but without the explicit emissions-reduction constraints.
