Nuovi strumenti conoscitivi e finanziari per la riduzione del rischio idrogeologico

The overall objective is to minimize the flood risk in a region by transferring financial resources from damage covering to damage preventing, assuming that: 1. Some preventive measures exist whose cost is by far less than the cost of covering the damages they prevent. 2. These preventive measures require target investments (project costs), whose amount cannot be sustained by a Central Public Administration (CPA) normal economic programming . 3. The above CPA aversion to investment on preventive measures is even worsened (not diminished!) by the frequent occurrence of catastrophes. In many cases, in fact a catastrophe occurrence triggers a negative financial flow, in the sense that resources previously allocated for prevention projects are diverted toward damage coverage. Points 1) and 2) are the main motivation for issuing project options (which may be subscribed by local public administrations, LPA) to support and finance risk prevention measures. Points 2) and 3) are the main motivations for accompanying the project options with a second financial instrument, similar to catastrophe bonds (which can be acquired by potential investors, PI), that: a) reinforces the remuneration in terms of gains (not simply loss reductions) subsequent to risk reduction; b) assures the CPA for the damage coverage in case of catastrophe, so that re-allocation of resources is not required. Both typologies of contracts incorporate a trigger mechanism, independent from posterioreconomic optimization and objectively evaluated by a third party arbiter. As a consequence, a dynamic interaction among CPA, LPA’s and PI’s takes place, which we represent by an evolutionary game modeled through a replicator dynamics. Taking as a case study the flood risk in the area of Florence (in Tuscan region) we assume realistic ranges for the model parameters and analyze, on such basis, the possible evolution and bifurcations of the game so as to gather qualitative indicators concerning the efficiency and convenience of the proposed financial instruments.