Science / Biology / Hydrosphere: The part of the physical environment that consists of all the liquid and solid water at or near the Earths surface.
Science / Weather / Geosphere: Considered the solid portions of the earth, including the hydrosphere and the lithosphere, as opposed to the atmosphere, which lies above it. At their conjunction is the biosphere. MORE
Science / Biology / Gaia: A hypothetical superorganism composed of the Earths four spheres: the biosphere, hydrosphere, lithosphere, and atmosphere. MORE