The costs of climate policies in a second best world with labour market imperfections

The critical role of labour market imperfections is explored in climate stabilisation costs formation, using a dynamic recursive energy-economy model that represents a second best world with market imperfections and short-run adjustments constraints along a long-term growth path. The degree of rigidity of the labour markets is a central parameter and a systematic sensitivity analysis of the model results confirms this. When labour markets are represented as highly flexible, the model results are in the usual range of existing literature, i.e. less than 2% GDP losses in 2030 for a stabilisation target at 550ppm CO2 equivalent. However, when labour markets rigidities are accounted for, mitigation costs increase dramatically. Accompanying measures are identified, namely labour subsidies, which guarantees against the risk of large stabilisation costs in the case of high rigidities of the labour markets. This complements the usual view that mitigation is a long-term matter that depends on technology, innovation, investment and behavioural change. The results support the view that mitigation is also a shorter-term issue and a matter of transition on the labour market.