Geography students in the field with Dr. Vatche Tchakerian.
Planet Earth is our home.
We humans live on the land that occupies 29 percent of the earth's surface. The remainder of the globe is covered by the oceans. An envelope of air surrounds the earth. These realms, the lithosphere, hydrosphere and atmosphere, form the environment for life on this planet. The study of these realms and their interactions with each other, the biosphere, and with humans, comprise the geosciences.