This is an image of a multi-storied apartment building surrounded by tall buildings in a city. The terraces of the apartment building are covered in vegetation, and there are lots of trees around the perimeter of the building as well.

Credit: NNECAPA/CC BY 2.0

Creating green roofs and living walls by planting vegetation in cities is an important step to combat the urban heat island effect, which causes urban areas to be much warmer than surrounding areas. In metropolitan areas much of the ground is covered with concrete, which absorbs heat and emitts carbon dioxide. Plants shade the surface and remove carbon dioxide from the air, helping to offset the effects of a warming climate.