GLOBAL CYCLES

1
GLOBAL CYCLES

• Earth
• Dynamic planet made up of several layers or
  spheres
• The Atmosphere
• The Hydrosphere
• Biosphere (Ecosphere)
• The Lithosphere

2

• The Hydrosphere
• liquid water (surface and underground), frozen
  water and water vapor.
• Biosphere (Ecosphere)
• Total of all the ecosystems on the planet, along
  with their interactions
• The sphere of air, water and land in which all
  life is found
• The Lithosphere Earths crust and upper mantle.
  Contains fossil fuels and minerals needed to
  support life

3

• The Atmosphere
• Thin gaseous envelope of air around the planet.
• Troposphere 017Km. Most of the planets air
• Nitrogen 78
• Oxygen 21
• Other gases Ar, CO2 1
• Stratosphere Very thin air, little moisture.
  Lower portion is extremely cold. Temperature
  rises with increasing altitude
• Mesophere Coldest layer of the atmosphere
• Thermosphere Uppermost layer of the atmosphere

4

• Energy flow and matter cycling in the Atmosphere
• Depends on two fundamental processes
• 1. Unidirectional flow of high quality energy
  from the sun travels through matter, living
  organisms, on or near earths surface then
  through the environment, mainly as low quality
  heat (within air or water molecules) and
  eventually through space as infrared radiation
• 2. Through the biogeochemical cycles

5
The Sun Our Energy Source

• Composed of H (72) and He (28)
• The temperature and pressure in its nucleus are
  high enough to cause nuclear fusion in H forming
  He
• Radiation from the sun cover distances of 150
  million Km (93 million miles) to the Earth in 8
  minutes
• About 34 of the solar energy that reaches the
  troposphere is reflected immediately through the
  clouds, chemical substances, and dust
• 66 heats up the troposphere, the earth,
  evaporates water and cycles through the
  atmosphere generating winds
• 0.023 captured by plants and bacteria(photosynthe
  sis)
• Some of the heat not reflected is decomposed into
  low quality radiation when interacting with the
  earth.

6

• ENVIRONMENTAL SYSTEMS RULE!!!