Climate Change and Respiratory Health

Current Evidence and Knowledge Gaps

Tim K Takaro; Kim Knowlton; John R Balmes


Expert Rev Resp Med. 2013;7(4):349-361. 

In This Article

Biomass Fuel Cooking/Heating Alternatives

Anthropogenic aerosol consists mainly of sulfate, nitrate, ammonium, black carbon (BC), and organic carbon (OC). These components interact with solar radiation in different ways depending on size and composition and contribute either a cooling or a warming forcing on climate.[78] BC absorbs solar radiation that causes a direct global warming effect,[79] and it also causes an additional warming effect after deposition onto snow and ice surfaces by reducing the reflectivity of snow.[80] Cooking with biomass fuels (wood, dung and crop waste) and open burning for agricultural purposes (deforestation and crop residue burning) are major sources of BC in the developing world. Fossil fuel combustion (diesel, oil and coal) is the primary source in developed countries. The strong warming due to the direct effect and snow-albedo effect of BC suggests that BC emission reductions could yield a short-term climate benefit. The Arctic may be particularly sensitive to the warming effects of BC.[81] The combustion sources that emit BC also emit other aerosol components that tend to cool climate, principally OC, so the net climate impact of emission controls is somewhat uncertain. A recent assessment, however, concluded that BC is the second-most important climate-forcing emission after CO2 and suggested that even after accounting for co emissions, which cool the climate, reducing diesel and residential biomass emissions would have a mitigating effect on global warming.[82] That said, a strong case can be made for a strategy to control BC emissions from indoor cooking with biofuel because of the health co-benefits of reducing biomass smoke exposure (decreased risks of childhood pneumonia, COPD, and lung cancer among women, and children in developing countries as well as cardiovascular disease among men and women).[83,84]