Also, and significantly, AB 32's cap-and-trade regulation is to create major reductions in the total GHG emissions by 2020. The exact numbers are not yet published. For Arizona to change position and not participate in the cap-and-trade system shows that California is, increasingly, going it alone.
In view of the effort to have the California Jobs Initiative passed at the ballot in November, this shows growing opposition in other states to regulations that are similar to, or a part of, AB 32. Cap-and-trade is a central part of AB 32, and a part that will bring great hardship to California businesses and citizens who are unable to find jobs.
Arizona has just signaled that they welcome businesses from California that are driven out by cap-and-trade rules, and will provide jobs in their state for those businesses.