Structure and Dynamics of Geophysical Systems

1. Water is a solvent. As it passes through the water cycle it dissolves minerals and gases and carries them to the oceans.
2. The waters of the oceans circulate mainly due to uneven heating.
3. The majority of Earth’s surface is covered by water.
4. The movement of water through an ecosystem is called the “water cycle.” Water goes through the process of evaporation, condensation, precipitation and runoff.
5. Global patterns of atmospheric movement affect local weather.
   1. Uneven heating of Earth’s surface produces weather systems.
   2. Cycling of water in and out of the atmosphere plays an important role in determining weather and climatic patterns.
   3. Ocean currents affect local and global weather conditions.
   4. A weather map can be used to predict temperature and precipitation for several days in a given area.
6. Rock normally goes through a continuing process from igneous to sedimentary to metamorphic and back.
   1. Igneous rock is formed when magma cools.
   2. Weathering of other rock forms sediments which accumulates in layers to form sedimentary rock.
   3. Metamorphic rock is formed when pressure and heat are applied to the sedimentary rock.
7. Natural processes that change the features of Earth’s crust include erosion, glaciation, weathering, earthquakes, and volcanoes.
   1. Dynamic forces change the features on Earth’s surface by building up or wearing down.
   2. New features on Earth’s crust are formed as a result of dynamic forces.
   3. Earth’s surface can change abruptly as a result of earthquakes and volcanic eruptions or Earth’s surface may change more slowly as a result of erosion, glaciation, and weathering.
   4. Volcanism is a force that uplifts Earth’s surface forming mountains and volcanoes.
   5. Forces that wear Earth’s surface down include weathering, glaciation, and erosion. Features formed as a result of this include soil and valleys.
   6. Fossils provide evidence that life and environmental conditions on Earth have changed.
8. Tools such as map projections and topographical maps may be used to interpret features of Earth’s surface.

Origin, Evolution, and Structure of the Universe

1. Time is related to motions within the Earth-Moon-Sun system.
   1. Day- Earth spins (rotates) on its axis every 24 hours.
   2. Month- The Moon orbits around Earth in about 29 days.
   3. Year- Earth orbits (revolves) around the Sun in approximately 365 days.
2. The length of daylight varies according to latitude and seasons.
   1. Since Earth turns on it axis and is tilted 23 ½ degrees, the intensity of sunlight varies throughout the year.
   2. The length of daylight on any point on Earth is dependent on its latitude and the position of Earth in its orbit relative to the Sun.
3. Phases of the Moon, eclipses and tides are caused by the relative positions of Earth, Moon, and Sun.
   1. The Moon revolves around Earth. Since the Moon rotates at the same speed that it revolves, the same side of the Moon is always facing Earth. The portion of the lighted side seen from Earth determines the phases of the Moon.
   2. An eclipse occurs when the Sun-Moon and Earth are in a line.
   3. Tides are motions of oceans’ water caused by the gravitational attraction between Earth-Moon and Sun. The highest tides occur when the Sun-Moon and Earth are aligned.
   4. Tides, phases of the Moon, and eclipses occur regularly and predictably.
4. Each of the planets differ from Earth in terms of distance from the Sun, atmosphere, gravity, surface features, temperature, speed of rotation, length of year, and the number of moons.
5. Comets travel around the Sun in highly elliptical orbits. Comets produce a glowing head and long tail. The tail always points away from the Sun.
6. The Sun’s gravitational pull holds the planets in their orbits, and the planet’s gravitational pulls holds their moon’s in their orbits.
7. Changes in positions of the constellations are the result of the relative motion of Earth.
8. The planets revolving around the Sun change their positions against a background of stars.
9. The Sun is a star and it shares characteristics with other stars.
10. The universe consists of billions of galaxies, each including billions of stars.