On the strategic effect of international permits trading on local pollution

We introduce a model of strategic environmental policy where two firms compete à la Cournot in a third market in the presence of multiple pollutants. Two types of pollutants are introduced: a local and a transboundary one. The regulator can only control local pollution as transboundary pollution is regulated internationally. The strategic effect present in the original literature is also replicated in this setup. However, we illustrate that when transboundary pollution is regulated through the use of tradable emission permits instead of non-tradable ones then a new strategic effect appears which had not been identified thus far. In this case, local pollution increases further and welfare is lowered. We also provide evidence from the implementation of EU ETS over the pollution of particulate matters (PM10 and PM2.5).