Download The Earth As A Planet

Earth and Space Science
- the scientific study of geology, oceanography,
meteorology, environmental science and astronomy
Earth and Space Science
Earth is generally thought of being made of four “spheres”:
1. Geology - Lithosphere
the hard outer crust (rocks) which covers 30% of our planet
two types:
a.
continental crust (rock type granite - old)
b.
oceanic crust (rock type basalt - young)
Earth and Space Science
2. Oceanography - Hydrosphere
- the combined volumes of water on Earth (i.e. Oceans, lakes,
rivers, glaciers, groundwater)
- 70% of Earth’s surface is covered by water (of which 97% is
salt and only 3% freshwater)
Earth and Space Science
3. Meteorology - Atmosphere
the layer of gasses which surround Earth (i.e. air)
99% of air is made up of only two elements (79% nitrogen and 20% oxygen)
other gasses include argon 0.9% and carbon dioxide 0.03%
Weather is the atmospheric conditions in a particular location over a short
period of time.
Climate is the average weather conditions in a region over a long period of time.
The Atmosphere
Earth and Space Science
4.
-
Environmental Science - Biosphere
the global community of living organisms and their
environment
life has been found ranging from 41 km above Earth’s surface
to a depth of 5 km into Earth’s crust