The source of the earth's climate and life on earth is the

The source of the Earth's climate and the life on earth is the Sun. The sun is the primary energy source of every living things on the surface and essential in earth's climate system. The sun is also the most important agent in photosynthesis, a process used by plants and trees to produce food, energy, and oxygen. 

Master planned communities outside of chicago. note: population density means people living in an area per square mile. chicago, an urban and highly populated area has a much more higher density than a desert, amish community, settlement, or nomadic region.