Got this from the list server from CARB:

The California Air Resources Board has just unveiled its revamped
Drive Clean website.

Please view: DriveClean.ca.gov. The site ranks cars by smog and
greenhouse gas emissions, and provides a variety of tools to
search and compare vehicles by environmental impact, efficiency,
cost and incentives. Check out www.DriveClean.ca.gov to find out
more. For more information, please contact Lisa Chiladakis at
[email protected] or at 916.327.2932.