Cities in a way can be a refuge because they have lots of these marginal left-over aid spaces. A study from the Conservation Charity Zoological Society of London found that restoring biodiversity in urban environments could boost wildlife and help protect city residents. Every year around the world, we're increasingly seeing our cities getting hit by dangerous and damaging floods. Climate Central estimate 275 million people worldwide live in areas that will eventually be flooded at three degrees Celsius of global warming.