Earth science

• Earth Science encompasses all sciences that seek to understand Earth and Earth's neighbors in space
• What Earth Science includes

  • Geology
  • Oceanography
  • Meteorology
  • Astronomy
• Big Bang Theory


  13.7 billion years ago, creation of all matter, hydrogen and helium the first, more complex elements evolved through time
• Steady State Theory


  The expanding universe, the Doppler effect is used to document the expanding universe, red shift, Hubble's Law
• Nebular Hypothesis


  The solar system formed from a collapsed nebula, observations support this idea
• Nebula formation

  1. Gas and dust, rotates and is held together by gravitational force

  2. Collapsed mass forms a proto-sun due to gravitational force

  3. Disk is "cleared out" due to the immense amount of energy released, sun is formed, dust and gases cool and condense in defined orbits around the sun
• Evidence for Nebula Hypothesis

  • Orion Nebula
  • Collapsed nebulae discs found in the Orion nebula
• Early Earth was homogenous and very hot
• Segregation of elements

  Gravitational force leads to compositionally and physically distinct layers
• Layers of the Earth

  • Inner Core
  • Outer Core
  • Mantle
  • Crust
• The Crust


  • It is very thin compared to the other three layers, makes up 1% of the Earth, broken into many pieces called plates
• The Mantle


  • The largest layer of the Earth, divided into upper and lower sections
• The Outer Core


  • Liquid, made up of iron, very dense
• The Inner Core


  • Solid, temperatures and pressures so great that the metals are squeezed together and are not able to move
• Spheres of the Earth

  • Atmosphere
  • Biosphere
  • Hydrosphere
  • Lithosphere
  • Anthrosphere
• Atmosphere


  • Reaches over 560 kilometers from the surface, supports life on Earth, absorbs energy from the Sun, recycles water and chemicals, provides moderate climate, protects from radiation and vacuum of space
• Layers of the Atmosphere

  • Thermosphere
  • Mesosphere
  • Stratosphere
  • Troposphere
• The biosphere is the life zone of the Earth and includes all living organisms and organic matter that has not yet decomposed
• Biotic


  Living parts or components
• Abiotic


  Nonliving parts or components (air, water, temperature)
• Hydrosphere


  • Includes all water on Earth, water is the basis of all life
• Lithosphere


  • The solid outermost shell of a rocky planet, includes the crust and uppermost layer of the mantle, broken up into different plates
• Anthrosphere


  Interactions of Homo sapiens with all aspects of the environment
• Earth's three natural cycles

  • Water Cycle
  • Nitrogen Cycle
  • Carbon Cycle
• Water Cycle


  • Sun fuels the evaporation, water is naturally purified as it evaporates from unclean bodies
• Nitrogen Cycle


  • Nitrogen is a gas in the atmosphere, important for animals and decomposers, plants consume nitrogen from animal remains
• Carbon Cycle


  • Carbon is found as a gas in the air as carbon dioxide, plants use carbon dioxide, water and sunlight to grow, animals receive carbon by eating plants, animals release carbon dioxide as they breathe
• The sun fuels the water cycle
• Plants create and take gas out of the air during the carbon cycle
• Decomposers help plants consume materials in the nitrogen cycle
• Animals release gas into the air as they breathe in the carbon cycle
• The water cycle helps keep lakes clean
• Weather begins with the sun
• Weather


  The state of the atmosphere with respect to heat or cold, wetness or dryness, calm or storm, clearness or cloudiness
• Climate


  The average course or condition of the weather at a place usually over a period of years as exhibited by temperature, wind velocity, and precipitation
• Some weather factors

  • Wind
  • Precipitation
  • Temperature
  • Cloud cover
• Seasons exist because the earth tilts on its axis towards the sun at different angles
• Air temperature


  The measure of the average amount of motion in particles
• Wind


  A natural movement of air of any velocity, especially the earth's air or the gas surrounding a planet in natural motion horizontally
• Humidity


  The amount of water vapor present in the air, relative humidity is a measure of the amount of water vapor present compared to the amount needed for saturation at a specific temperature