The main sources being diesel vehicles and in less industrialised countries from the burning of biomass. Up in the atmosphere it absorbs sunlight and increases air temperature, while on the ground it adds to air pollution, particularly in urban areas. It can also darken snow and ice, increasing absorption of sunlight and has been linked to accelerating melting of the Arctic.
The contribution of black carbon to warming is thought to be 100-2000 times greater than CO2. However, it has a much shorter lifetime, staying in the atmosphere for only a number of days or weeks compared to 100 years for carbon dioxide (CO2), meaning benefits from reducing emissions will be rapidly noticeable.
In a study this week, the UN Environment Programme (UNEP) estimate we could quickly reduce ‘near-term' global warming by 0.5 degrees Celsius by tackling black carbon emissions. Reduction measures would have an even greater benefit in the Arctic where it could reduce warming by 0.7 degrees. Read the full report here.
Source: William McLennan, The Ecologist.
