Ongoing Projects

To prevent carbon leakage induced by unilateral carbon pricing, the EU has designed a Carbon Border Adjustment Mechanism (CBAM) that taxes imports based on their carbon content. Since estimating the carbon content of imports is very complex, CBAM will be applied only to a few emission-intensive sectors. We argue that, as a consequence of its limited applicability, CBAM is unlikely to effectively eliminate leakage. We propose a simple alternative route towards leakage prevention with significantly lower information requirements and administrative burden which can be applied to all tradable sectors: the Leakage Border Adjustment Mechanism (LBAM). LBAM offsets the cost disadvantages of domestic producers relative to foreign competitors induced by unilateral carbon pricing by implementing import tariffs and, potentially, export subsidies that hold trade constant at the level before the introduction of carbon pricing. LBAM requires knowledge only about domestic product-specific output-to-emissions elasticities and import demand and export supply elasticities but does not depend upon information on the carbon content of imports. To quantify the welfare and emission effects of LBAM and to compare it to CBAM, we simulate a unilateral carbon-price increase in the EU using a granular structural trade model with 57 countries and 121 sectors. We find that LBAM is very effective in preventing leakage, while the EU CBAM is not. 

We study whether trade agreements should also constrain domestic policies from the perspective of monopolistic competition models with heterogeneous firms and multiple sectors. We consider shallow and deep trade agreements, modeled according to GATT-WTO rules. We show that, in contrast to deep agreements, shallow agreements, complying with market access commitments and tariff bindings, are not sufficient to achieve global efficiency because terms-of-trade improvements can be obtained without reducing foreign market access. We also show how the performance of different trade agreements is affected by firm heterogeneity and that the distortions arising from uncoordinated domestic policies increase when trade costs fall. 

We demonstrate that the estimation of gravity equations of trade flows suffers from an omitted variable bias when firms are granular and behave oligopolistically. We show how to correct for this bias in the estimation of both firm- and industry-level gravity. Using French and Chinese export data, we find that the oligopoly bias leads to a substantial underestimation of the effects of distance on trade flows. In a calibrated version of the model, the welfare gains from a trade liberalization are found to be almost twice as large under oligopoly as under monopolistic competition.