Black Carbon considered as a potent greenhouse gas has been resisted by India which opposes its inclusion in the list of GHG’s under the UNFCCC mechanism.
What is Black Carbon?
Considered as a climate change inducing agent by some, it is formed through the incomplete combustion of fossil fuels, biofuel, and biomass, and is emitted in both anthropogenic and naturally occurring soot. It basically consists of pure carbon in several linked forms. Black carbon absorbs heat and reduces albedo, thus considered as a player in climate change. Its lifetime is however only a few weeks in the atmosphere. Its effects are usually regional and due to its short life span, experts believe mitigating efforts can result in quicker gains.
Black carbon is important in Indian and Chinese context as both countries are emitters of Black carbon in large amounts. India commissioned a study soon after Cancun- The Black Carbon Research Initiative to go into the complexities of its global warming potential given the limited understanding of Black Carbon at present. Given the large amount of black carbon coming from cookstoves used widely by rural populations, mitigation measures for developing countries directed at reducing black carbon levels may not be feasible.
According to reports, Black Carbon removal may even be counter productive and may increase global warming rather than mitigating it. Associate Professor S K Satheesh of IISc, said- “the removal of BC would mean the removal of other kinds of carbon (sulphate and organic) that act as coolants. This would thereby become more harmful for Global Warming’s cause.”
Satheesh added that the very nature of carbon aerosols is important: “BC is 23 per cent absorbing and 77 per cent scattering, while organic carbons are 97 per cent scattering and 3 per cent absorbing,” he said, adding that the combined scattering is much larger than the combined absorption, thereby having cooling effects.
Naturally other countries would want Black carbon to be included in the list as India and China are together the two most important global emitters of Black Carbon. Given the limited research on role of black carbon, more research is needed to settle the issue of Black Carbon paradox.