Trees help cool the planet by inhaling and storing harmful greenhouse gases into their trunks, branches, and leaves, and releasing oxygen into the atmosphere in return. In cities, trees can reduce overall temperature by up to eight degrees Celsius. With more than half of the world’s population living in cities—a number expected to increase to two thirds by the year 2050—pollution and overheating are becoming a real threat. Fortunately, a mature tree can absorb an average of 48 lbs of carbon dioxide per year, making cities a healthier, safer place to live.