Black carbon (BC) has a unique and important role in the Earth’s climate system because it absorbs solar radiation, influences cloud processes, and alters snow and ice cover melting. BC is the second-largest climate warmer, after carbon dioxide. A large fraction of atmospheric black carbon concentrations is due to anthropogenic activities. Concentrations respond quickly to reductions in emissions because black carbon is rapidly removed from the atmosphere by deposition. Thus, black carbon emission reductions represent a potential mitigation strategy that could reduce global climate forcing from anthropogenic activities in the short term and slow the associated rate of climate change.

Comparison with remote sensing observations indicates that global atmospheric absorption attributable to black carbon is too low in many global aerosol models. It is therefore important that measurements are done on a global scale.