The earth has three major climate zones; polar, temperate and tropical. The four seasons are fall, winter, spring and summer. The seasons are caused by the tilt of the earth. The earth rotates from west to east on its axis once about every twenty-four hours. The imaginary axis of the earth has a diagonal tilt of a 23.5° angle. As the earth rotates around the sun for several months it tilts toward the sun and for the equal amount of time it tilts away from the sun.
When the Northern Hemisphere tilts toward the sun, it is considered summer. When the Southern Hemisphere tilts away from the sun that will be winter in that area. The greatest amount of heating occurs when the sun is most direct, therefore summer and winter do not occur simultaneously around the world. It is during spring and autumn when neither hemisphere is tilted toward the sun.
Temperature: Climate can be referred to as the generalized weather of an area. There are many factors that affect climate and are often times classified by a combination of temperature (torrid, temperature, frigid) and rainfall (wet, humid, sub-humid, semi-arid). In the most commonly used systems, rainfall for the torrid and temperature zones and temperatures for the colder zones are stressed.
Rainfall: Due to the general direction of wind, land surface near the water usually have more rainfall than the inland. Climate is also dependent upon the amount of annual rainfall. Arid or very dry area receive an annual rainfall of 0-10 inches of rain. Semi-arid areas receive 10-20 inches. Areas receiving 20-40 inches of rain annually are considered humid. Over 40 inches of rainfall annually are considered very humid.
Wind-belts move slightly with seasons. This shifting causes one season to have more rain than the other. Temperature is an element that makes weather. All weather is dependent upon the temperature changes in different parts of the atmosphere.