Less than three months ago the North American Climate Summit, held right here in the Windy City, brought together mayors, civic leaders, and businesses from across the U.S., Canada and Mexico to sign a charter pledging to reduce greenhouse emissions and address the impact cities have on climate change.  But despite the overwhelming support, some of the most important players living at the forefront of innovation, strategy, storytelling and creative thinking were missing from the table.  Advertising and PR agencies.  These are the professionals who determine what and when we buy, and much of what we believe.  Their job is to tell stories, deliver on the most powerful ideas and campaigns that in turn change our behavior and perception of not just brands, but of society as a whole.