(a) Climate cost C_FB(G)	(b) Dynamics of GHG stock
(c) Adaptation and mitigation funding levels	(d) Adaptation and mitigation funding shares

Figure 5. First-best benchmarks. Author's own elaboration.

(a) Difference in climate cost: C(w_t, G_t) − C_FB(G_t)	(b) Difference in GHG stock: G_SB,t − G_FB,t
(c) Promised contribution value: w_t	(d) Total funding: I_t
(e) Adaptation funding: a_t	(f) Mitigation funding: m_t
(g) Adaptation share: a_t / I_t	(h) Mitigation share: m_t / I_t

Figure 6. Comparison of dynamics under the first-best and the second-best (SB) contract for probabilities of contract enforcement rho in {0.80, 0.85, 0.90, 0.95, 1.00}, with initial total funding set to 8% of the first-best level in 2015. Author's own elaboration.

The author does not numerically solve the full Bellman problem in this repository because a global solution is computationally intensive and highly sensitive to grid construction and interpolation choices. Nevertheless, a full-solution implementation can reproduce the patterns shown in Figure 6.