New black carbon research helps advance climate solutions

Climate researchers have observed reductions in black carbon's warming effect in California, an unexpected benefit from two decades of the state's clean air laws. Black carbon, a form of particulate pollution associated with biomass burning and vehicle emissions, has been recognized as a major contributor to global warming.

In another aspect of black carbon research, computer scientists have discovered that cell phones can be used as a real-time, ultra low-power black carbon data collection system.

V  Ramanathan, distinguished professor of climate and atmospheric science at Scripps Institution of Oceanography at University of California, San Diego, will present results from the IMPROVE monitoring network during a press conference at the 2010 American Geophysical Union (AGU) Fall Meeting in San Francisco.

The results show that annual average black carbon concentrations in California have decreased by about 50 per cent over the past 20 years, in direct proportion to a decline in fossil fuel emissions. The study, which was led by Scripps researcher Ranjit Bahadur, will be published in the 14 December issue of the journal Atmospheric Environment.

"This study serves to confirm that some successes have already been achieved in combating climate change using existing, affordable remedies," said Ramanathan, who is a co-author of the California Air Resources Board (ARB)-funded study.

"This study demonstrates that ARB's efforts to cut air pollution, whether by promoting cleaner cars or controlling agricultural burning, have significantly reduced threats to public health while also helping address climate change," said California Air Resources Board chairman Mary D Nichols. "The more we learn about the atmosphere, the more it's clear that cleaning up the pollution that harms our lungs is also beneficial for slowing the rate of climate change."