Associated Press: A day before he was to welcome hundreds of high-ranking officials for a summit on greenhouse gas emissions, Gov. Arnold Schwarzenegger raised the environmental stakes in California. Schwarzenegger signed an executive order committing the state to obtaining a third of its electricity from renewable sources by 2020. California previously had committed to producing 20 percent of its power from renewables such as wind and solar by 2010. “I am proposing we set the most aggressive …