Annual Science Update 2013

This report by the Climate and Clean Air Coalition (CCAC) Scientific Advisory Panel (SAP) provides basic information about short lived climate pollutants (SLCPs) as well as new scientific findings relevant to policy. It provides an overview of what the Latest Scientific Findings say about the Actions Undertaken by the CCAC and offers important new information on sources of SLCP emissions and their impacts.

New information useful to policymaking is becoming available about the SLCP sources and impacts:

• Gas flaring in the Arctic is now realized to be a more important source of black carbon particles in the Arctic than in earlier estimates.  The deposition of these particles is known to contribute to the accelerated melting of ice.
• The kerosene lamps commonly used in households in South Asia, Africa, and parts of Latin America have been confirmed to be a major source of indoor black carbon air pollution in these regions.  Controlling this source would not only reduce air pollution, but also bring regional and global climate benefits.  And of particular interest to policymaking, experts note that affordable alternatives to kerosene lamps are already available.  A comprehensive view of residential energy use would help identify optimal methods to lower emissions associated with cooking, heating and lighting.
• New information shows that diesel generators are an important source of black carbon emissions in countries where public power supply lags behind electricity demand (e.g. India, Nepal and Nigeria).
• New evidence confirms that reducing black carbon emissions from diesel engines (both generators and vehicles) and some types of cook stoves provides clear climate benefits.
• Recently published data from the US indicate greater leakage of methane from energy facilities than earlier suspected.  This includes emissions from fossil fuel production facilities in the Gulf of Mexico and from distribution systems in the LA basin, and suggests leakage rates may be underestimated in most countries.