Health Co-Benefits and Mitigation Costs – A Climate Change Policy Study

Climate policies that apply mitigating actions to lower greenhouse gas emissions using alternative energy sources can also offer health benefits, according to the study “Health co-benefits and mitigation costs as per the Paris Agreement under different technological pathways for energy supply.”

According to the World Health Organisation (WHO), air pollution is the fifth biggest health risk, responsible for one in every nine deaths annually. Some related studies present higher figures than those of the WHO. The study states that one of the main sources of air pollution is the combustion of fossil fuels, which is also the source of greenhouse gas emissions.

Policies aim to lower air pollution also, lower greenhouse gas emissions, and generate health co-benefits. Because of these, there is a growing interest in policies and research mitigation costs and health benefits.

The study employs an integrated framework that estimates the global and regional co-health benefits, mitigation costs, and trade-offs of various technological pathways for achieving the Paris Agreement. These technology scenarios are based on the 5^th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).

Climate mitigation technologies refer to ways to reduce emissions through the use of bioenergy, nuclear power, and carbon capture and storage (CCS).

For each mitigation pathway, different levels of energy mix are assumed.

The scenarios used in the study are the following:

• First is the baseline scenario with no climate policy.
• Second, a scenario with all available technology used without any limitation,
• Third, where bioenergy is limited around the globe,
• Fourth, low availability of carbon capture and storage (CCS) technology, and
• Fifth, there is a nuclear phase-out scenario with no installation of new ones.

For each scenario, the study assessed the amounts of greenhouse gas emissions and air pollutants, as well as the associated mitigation costs and health benefits.

The study covers the major pollutant species, such as black carbon, organic carbon, nitrous oxides, sulphur dioxide, carbon monoxide, ammonia, and non-methane volatile organic compounds. The sum of black carbon and organic carbon likely constitutes fine particulate matter, or PM2.5, which is the most harmful air pollutant in terms of its health damage.

Premature deaths attributable to PM2.5 are caused by ischemic heart diseases (IHD), chronic obstructive pulmonary diseases (COPD), stroke, lung cancer, and acute lower respiratory infection (ALRI).

The study shows that when there is no climate policy to curb emissions, premature deaths increase continuously. Deaths will reach almost 4 million in 2050 and 3.2 million in 2030. Causes of deaths can be attributed to concentrations of air pollutants and increasing populations, as population growth can also influence air pollution.

The study generally shows that health co-benefits exceed mitigation costs when using different energy supplies across all emission reduction pathways. This result is also consistent with other studies that analyse different emissions targets.

The effects of climate policies on the amounts of air pollutant emission vary in countries, and so do the health benefits.

The largest health benefits are found in China and India. India showed the largest benefit, and China will benefit most in the mid-term or by 2030.  

However, in some developed countries like Canada, Australia, South America, and the USA with low population densities, health benefits are not larger than mitigation costs because significant air pollution policies have already been implemented. The health co-benefits in these regions are not enough to compensate for climate mitigation costs.

Health benefits arising from mitigation policies can also incentivise decarbonization efforts, especially in China and India, where health benefits are high.

FEATURED IMAGE CREDIT: “Niagara Falls” by Karl Hipolito