We analyze the strategic interaction between mitigation (public good) and adaptation (private good) strategies in a climate agreement.We show that adaptation can lead to larger self-enforcing agreements, associated with higher global mitigation levels and welfare if it causes mitigation levels between different countries to be no longer strategic substitutes but complements. Thus, the fear that adaptation will reduce the incentives to mitigate carbon emissions may be unwarranted. We argue that our results extend to many important public goods. The purchase of private goods may not crowd out the provision of public goods, as this is commonly believed.

Aquaculture is contributing at an increasing rate to world seafood supply. The interaction between fisheries and aquaculture is especially important for the seafood market where supply of wild and farmed fish can affect price dynamics. We examine market interactions in the French fresh sea bass and sea bream markets. We test for long term price parity between farmed and wild products for these two species, applying a bivariate cointegration approach to market delineation. We also conduct the Law of One Price (LOP) test between price series.Our data base consists of monthly domestic price series for fish purchased by French households from 2007 to 2012. Our empirical results show that the fresh fish markets for whole wild and farmed sea bream are partially integrated, while those for whole wild and farmed sea bass are not integrated. The substantially higher price for wild sea bass relative to farmed sea bass suggests that consumers may be more sensitive to seafood production processes in higher-value species.