Effect of a tariff on the environment and welfare: The case of an environmental differentiated duopoly in a Green Market

Employing a model of environmental quality-differentiated products, we analyze the effect of an ad valorem tariff on the unit emission level of the products, the environment and welfare in the Bertrand and the Cournot duopoly cases, respectively. We show that the effect of the tariff policy depends on the mode of market competition and the degree of marginal social valuation of environmental damage.