California is on the front lines of climate change with trees dying and wildfires raging on drought-parched land. Perhaps recognizing the urgency of acting on the growing menace from global warming, Gov. Jerry Brown on Thursday signed sweeping climate change legislation that sets a more ambitious target for what was already the toughest greenhouse gas reduction goals in the nation. SB 32 requires the state to slash greenhouse gas emissions at least 40 percent below 1990…