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Begin New Search Topic Climate Change Author Joschka Wanner

1. New Trade Models, Same Old Emissions?

Author:
Robin Sogalla, Joschka Wanner, and Yuta Watabe
Publication Date:
04-2024
Content Type:
Working Paper
Institution:
Kiel Institute for the World Economy (IfW)
Abstract:
This paper investigates the elusive role of productivity heterogeneity in new trade models in the trade and environment nexus. We contrast the Eaton-Kortum and the Melitz models with firm heterogeneity to the Armington and Krugman models without heterogeneity. We show that if firms have a constant emission share in terms of sales — as they do in a wide range of trade and environment models — the three models’ emission predictions exactly coincide. Conversely, if firms have a constant emission intensity per quantity — a prominent alternative in the literature — the emission equivalence between the three models breaks. We provide a generalization that nests both constant emission shares in sales and constant quantity emission intensities as special cases. We calibrate the models to global production and trade data and use German firm-level data to estimate the key elasticity of how emission intensity changes with productivity. Our multi-industry quantification demonstrates that the role of firm heterogeneity depends both on the model and the estimated parameters. Moving from the Armington model to the EK model increases the emissions effect on trade, while moving from the Krugman model to the Melitz model decreases the emission effects on trade.
Topic:
Climate Change, Globalization, International Trade and Finance, Carbon Emissions, and Sustainable Development
Political Geography:
Global Focus

2. The Consequences of Unilateral Withdrawals from the Paris Agreement

Author:
Mario Larch and Joschka Wanner
Publication Date:
11-2022
Content Type:
Working Paper
Institution:
Kiel Institute for the World Economy (IfW)
Abstract:
International cooperation is at the core of multilateral climate policy. How is its effectiveness harmed by individual countries dropping out of the global mitigation effort? We develop a multisector structural trade model with emissions from production and a constant elasticity of fossil fuel supply function to simulate the consequences of unilateral withdrawals from the Paris Agreement. Taking into account both direct and leakage effects, we őnd that a US withdrawal would eliminate more than a third of the world emissions reduction (31.8% direct effect and 6.4% leakage effect), while a potential Chinese withdrawal lowers the world emission reduction by 24.1% (11.9% direct effect and 12.2% leakage effect). The substantial leakage is primarily driven by technique effects induced by falling international fossil fuel prices.
Topic:
Climate Change, International Trade and Finance, Fossil Fuels, Carbon Emissions, and Paris Agreement
Political Geography:
Global Focus and United States of America