How sustainable is San Diego?
        
        
    
   
   San Diego ranks as the 17th most sustainable big city in the United States according to the non-partisan group SustainLane.com. Tom Fudge finds out more about the study and San Diego's ranking.
    Guests: 
   
- Warren Karlenzig chief strategy officer of SustainLane.com and the director of the US Sustainable Cities Ranking.
 - Mike Lee is the environment reporter for the San Diego Union Tribune.