Explanation:
1. Conduction : When two bodies are in direct contact, the heat transfer is said to be taken place by conduction.
Convection : Conduction is the heat transfer which takes place by actual motion of matter.
Radiation : Radiation is the heat transfer with the help of electromagnetic waves.
2. The earth receives heat from the sun by radiations. This heat is taken up by the earth and is radiated back to the atmosphere.
3. Changes in the earth's orbit around the sun, changes in the axis of rotation and change sin ocean currents are three natural factors that affect earth's climate.
4. Emission of green houses gases to the atmosphere, deforestation, polluting the water bodies are three man made factors that affect earth's climate.