Geography : weather & climate

• Climate


  Set of atmospheric phenomena, such as temperatures, precipitation, wind, which characterize a given place, during a given period. It is a synthetic presentation of the behavior of the atmosphere in a given region, which is based on long-term statistics
• Weather


  Set of immediate atmospheric phenomena. It is defined by instantaneous and local values of temperature, precipitation, pressure, wind, ...
• Components and factors affecting climate

  • (a) : The action of the Sun on the Earth. (b) : the atmosphere and the unequal distribution of temperatures. (c) : thermal transfers on Earth. (d) : the role of the oceans. (e) : unequal precipitation.
• The two rotations of the Earth ?

  Rotation (on itself)

  Revolution (around the Sun)
• The inclination of the Earth with respect to its axis is about 23,26
• The rotation of the Earth on itself lasts about 24 hours. Sunrise and sunset vary according to the latitude and longitude.
• The revolution of the Earth around the Sun takes 365 days, 6 hours and 4 seconds. Its orbit is not a perfect cycle. It forms a slight ellipse, and the Earth comes closest to the solar star in January.
• The amount of sunlight will be different depending on the time of year. In the Northern hemisphere, summer solstice (around 21st of June) is the longest day of the year while winter solstice (around 21st of December) is the shortest. Equinoxes occur around 21st of March and 21st of September when the day is equally as long as the night.
• Temperature and the percentage of humidity depend greatly on the action of the Sun. The Sun's rays act with varying strength according to the angle of inclination of the Earth. The maximum amount of sunshine occurs when the Sun's rays arrive perpendicular to the ground.
• When the angle of the Sun's rays is less than 45 degrees


  Energy flow disperses over a larger area, resulting in a decrease in insolation and température.
• Special times of the year


  • Summer solstice
  • Winter solstice
  • Equinoxes
• The thermal zones are marked according to the seasons and the inclination of the Earth on its axis
• Thermal zones

  • Hot zones
  • Temperate zones
  • Cold zones
• Hot zones are located around the equator and the tropics
• Temperate zones are located around 45 degrees north or south of the equator
• Cold zones are located near the polar circles
• These air masses undergo movements that condition climates
• There are only two seasons between the tropics 


  The temperature is +/- the same because the position of the Sun doesn't change a lot so there is only the : dry and rain seasons

  Due to pressure system