2. UNIT ONE OF THE GCSE COURSE

8. The lithosphere (or geosphere) The Earth's solid surface, including continental and oceanic crust as well as the various layers of the Earth's interior.

9. The hydrosphere (water) The hydrosphere is the sphere which includes all of the water on Earth. 71% of the Earth is covered by water

10. The atmosphere - Air The atmosphere is a gaseous layer that surrounds the Earth. It consists of a mixture of gases composed primarily of nitrogen, oxygen, carbon dioxide, and water vapour.

11. The biosphere (living things) The biosphere is all life on earth, including man, and all organisms (both plants and animals).

12. How are the Spheres connected?  The four spheres are closely connected in many ways. For example, many birds (biosphere) fly through the air (atmosphere), while water (hydrosphere) often flows through the soil (lithosphere). In fact, the spheres are so closely connected that a change in one sphere often results in a change in one or more of the other spheres.  Warm water from the ocean (hydrosphere) evaporates until the atmosphere above can hold no more. The wind (atmosphere) moves the moisture (water vapour in the atmosphere) over a colder mountainous area (lithosphere). The atmosphere above it becomes colder and the water vapour condenses and changes to rain. The rain (atmosphere) falls on the land (lithosphere) and returns to the oceans (hydrosphere).

13. An ‘event’ may be climate change. For example the burning of trees (biosphere) will release carbon dioxide (into the atmosphere) which traps heat and changes climate patterns (atmosphere) that lead to melting of ice sheets and cause sea levels to rise (hydrosphere). This reduces the land (lithosphere) available for human occupation.

14. Assignment On the Front On one piece of white paper Draw an illustration of the spheres and label each of the 4 spheres. On the Back Create 4 boxes on your white paper, one for each sphere (biosphere, atmosphere, lithosphere, hydrosphere). Define each ‘sphere’. For each sphere, add at least one way in which it: o benefits people o can negatively affect, or harm, people o people can negatively affect the ‘sphere’