Chapter 2 - The Earth System

The Earth system is made up of 5 individual spheres that are constantly interacting with one another in order to ensure dynamic and life sustaining nature of our planet. The atmosphere is the blanket of air that adheres to the Earth’s surface. The lithosphere (lithos meaning rock) is below the atmosphere, and is the outermost shell of the solid earth. 71% of the Earth’s surface is covered by the ocean which lies between the lithosphere and the atmosphere, this is the hydrosphere. The cryosphere includes all forms of frozen water, including glaciers, floating ice, snow cover, and permafrost. Finally, the biosphere is the zone of life, the home of all living things; which includes the Earth’s vegetation, animals, and human beings. This picture, ones again from Yellowknife, illustrates 4 of the 5 spheres interacting: lithosphere, atmosphere, biosphere, and the hydrosphere. Had we been here earlier in the season (or later for that matter) we may have captured all 5.