Climate change and cities: a wake-up call

More than half the world's population live in cities, many of which are increasingly vulnerable to the impacts of climate change; cities, however, are also emerging as the innovative "first responders" in dealing with climate change; climate change will stress cities in many ways -- there will be more heat waves, threatening the health of the elderly and infirm; droughts will also become more commonplace in many cities, while in coastal communities too much water may be the problem, due to sea-level rise and more extreme coastal flooding