Answer:
the main ones are Variations in the sun's energy reaching Earth.
Changes in the reflectivity of Earth's atmosphere and surface.
Changes in the greenhouse effect, which affects the amount of heat retained by Earth's atmosphere.
Step-by-step explanation:
caused by the variation in the occurrences of some climatic factors; rainfall, temperature, light wind: biotic factors; predators, parasites, soil micro-organism, pest and diseases: and edaphic factors; soil pH,