Including the Feedback of Local Health Improvement in Assessing Costs and Benefits of GHG Reduction

Ancillary benefits of greenhouse gas (GHG) mitigation refer to benefits from GHG mitigation in addition to lowered adverse impacts of global climate change. A major ancillary benefit of GHG mitigation is reduced local air toxins, which improves health. The purpose of the study is not to determine whether ancillary benefits of GHG mitigation can or cannot justify GHG mitigation. Rather, we discuss how an important benefit of addressing GHG emission — the local health effects — should and can be incorporated using the approaches put forth. A CGE model is used for simulating a carbon tax policy. A health effects submodel takes the local air emissions output from the CGE model and assesses the implications for ambient air concentration, health, and labor supply. Labor and medical expenditure changes are fed back into the economy. Applying this approach to Thailand, when health feedback is included we find that: (1) negative impact on GDP under a carbon tax drops by 45%, and (2) welfare improves for households and cleaner producers.