The Sacramento Bee published a great interactive map by Mitchell Brooks and Philip Reese that chronicles the history of California county unemployment rates from 2008 through May 2012. You can pick specific months or hit the PLAY button and watch the whole disappointing episode play out.
The disparity between coastal and inland regions is quite obvious. Also, playing the graphic makes it clear which areas suffer from perennially high unemployment rates—Imperial, Merced, Colusa. At peak unemployment in January 2010, only nine counties posted unemployment rates below 11% and five counties breached 21%..