Border Carbon Adjustment: Questions and Answers (But More of the Former)

This briefing paper examines the economic, legal, and geopolitical challenges of implementing Border Carbon Adjustments (BCAs) to address industrial competitiveness and carbon leakage. It analyzes the tension between unilateral trade measures and international climate principles, specifically the UNFCCC's principle of common but differentiated responsibility.

• Domestic producers in trade-exposed energy-intensive sectors—specifically iron and steel, chemicals, pulp and paper, cement, aluminum, and sometimes petroleum refining—are most vulnerable to competitiveness impacts when unilateral climate actions are taken.
• To be compatible with WTO law, BCAs must avoid discrimination between domestic and foreign producers of like products (national treatment) and must not discriminate between like products based on the country of production (most favoured nation).
• For a BCA to potentially be cleared under GATT Article XX exceptions, it should account for all climate policies of trading partners, recognize differences between individual producers rather than using national averages, and be implemented only after unsuccessful efforts to reach a multilateral agreement.
• Narrowly cast BCAs that cover only basic commodities (like raw aluminum) may protect the primary sector but inadvertently penalize domestic manufacturers of value-added goods (like bicycles) by increasing input costs without taxing imported finished products.
• BCAs face significant administrative hurdles, including the lack of existing data for plant-by-plant carbon footprint verification and the difficulty of creating a common metric to compare diverse climate policies, such as comparing China's energy efficiency efforts to a carbon tax.
• The use of BCAs may conflict with the UNFCCC principle of common but differentiated responsibility (CBDR), as 'levelling the playing field' ignores the premise that developed countries should bear a larger burden due to historical responsibility.

APA

Cosbey, A. (2009). Border Carbon Adjustment: Questions and Answers (But More of the Former). International Institute for Sustainable Development. https://www.iisd.org/system/files/publications/bali_bcas_questions_answers.pdf

Chicago

Cosbey, Aaron. Border Carbon Adjustment: Questions and Answers (But More of the Former). International Institute for Sustainable Development, 2009. https://www.iisd.org/system/files/publications/bali_bcas_questions_answers.pdf.

Wikipedia

{{cite report |last1=Cosbey |first1=Aaron |title=Border Carbon Adjustment: Questions and Answers (But More of the Former) |publisher=International Institute for Sustainable Development |date=October 2009 |url=https://www.iisd.org/system/files/publications/bali_bcas_questions_answers.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{cosbey2009border, author = {Cosbey, Aaron}, title = {{Border Carbon Adjustment: Questions and Answers (But More of the Former)}}, institution = {International Institute for Sustainable Development}, year = {2009}, month = oct, url = {https://www.iisd.org/system/files/publications/bali_bcas_questions_answers.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }