(Sködt McNalty/CBC) Hello, people! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. ( Sign up here to get it in your inbox every Thursday.) This week: Cities are on the front lines of climate action Banning plastic bags: Who’s done it? Blue box blues: A closer look at unrecyclable plastic Cities can be climate champions (Kazuhiro Nogi/Getty Images) When it comes to spewing carbon into the air, urban areas are among the biggest offenders. But cities also lead the way when it comes to taking significant action to get those emissions down, according to David Miller, director of international diplomacy for the C40 Cities Climate Leadership Group. "With a few exceptions, it’s been the leadership of the cities that’s really been pushing the envelope and moving towards what’s necessary, not just what’s easy," said Miller, a former mayor of Toronto. Research by C40, a network of 94 global cities committed to addressing climate change, shows about 70 per cent of the world’s greenhouse gas emissions come from urban areas. It’s predominantly from four sources: How we generate electricity. Transportation. How we heat and […]