The Atmosphere
71% of the earth is water. Water is distributed in one form or another through several of the earth’s layers. The lithosphere consists of the crust and the mantle. The crust is typically about 25 miles thick beneath continents, and about 6.5 miles thick beneath oceans. It is relatively light and brittle. This is where the tectonic plates move and earthquakes occur. The lithosphere includes all forms on the surface of the earth, such as mountains, valley on land and trenches and peaks under the ocean.
The mantle is a thick layer of rock below the earth's crust; it is about 1,800 miles deep. Water is found in the groundwater and water table in the lithosphere.
The hydrosphere layer contains all the water on the earth. It includes water in lakes and streams, subsurface water, the ice of glaciers and water vapor in the atmosphere. The mass of air that surrounds the earth is the atmosphere.
Water is found in the atmosphere in the form of rain, snow, hail, sleet, water vapor and the water droplets that make up clouds.
The mass of air that surrounds the earth is called the ATMOPSHERE. The atmosphere is made mostly of nitrogen, water vapor, carbon dioxide, and oxygen which accounts for one-fifth of the atmosphere. All these gases are held in the atmosphere by the earth's gravitational pull.
There are five layers to the earth's atmosphere:
TROPOSPHERE 0-7 miles from earth's surface
where clouds and weather are
contains water and dust particles
animals and commerical planes
contains ozone which warms air to 40 degrees F
little water vapor or dust
fighter planes
-90 degrees F (coldest part of atmosphere)
no aircraft, only very large helium balloons
930-3,000 degrees F
thickest layer of atmosphere
outer space begins about halfway through this layer at 180 miles
satellites, Sputnik, X-15
outer space
thin gases, no oxygen or gravity
shuttle, space capsules
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