The Board’s action is the third and final step California committed to as part of an agreement with automobile manufacturers and two federal agencies announced last May by President Obama in the Rose Garden to establish the harmonized national GHG standard.

The two other steps relate to compliance with the California standards in model years 2009 through 2011, prior to the initiation of the federal measure in 2012. The first allows California and the thirteen other states that had adopted California’s greenhouse gas standard to pool car sales from all 14 states instead of using a state-by-state basis for compliance; the second is a cost-reducing measure that permits existing federal data to be used to comply with California’s greenhouse gas standards for those years.

ARB studies indicate that, as a result of the national scope of the standard, a total of 941 million tons of carbon dioxide will be prevented from entering the atmosphere by cleaner cars in all fifty states by 2020, compared to 793 million tons had the standard been limited to California and the thirteen states that had adopted California’s standard.

The ARB is beginning work on a follow-up set of greenhouse gas regulations for light-duty vehicles (Pavley 2), targeting model years 2017 and following.