Weather, Seasons & Climate

Weather

  • Temperature, pressure, wind, humidity and precipitation, interact with each other.
  • They influence the atmospheric conditions like the direction and velocity of wind, amount of insolation, cloud-cover and the amount of precipitation. These are known as the elements of both weather and climate.
  • The influence of these elements differs from place to place and time to time. It may be restricted to a small area and for a short duration of time.
  • Very often this influence is described in the name of weather as sunny, hot, warm, cold, fine, etc depending upon the dominant element of weather at a place and at a point of time.
  • Therefore, weather is the atmospheric condition of a place for a short duration with respect to its one or more elements.
  • Two places even a short distance apart may have different kind of weather at one and the same time.

Seasons

Weather & Climate

  • Seasons are specified periods in a year which have similar weather conditions.
  • Season is a period of the year characterized by a particular set of weather conditions resulting from the inclination of the earth’s axis and the revolution of the earth round the sun.
  • The same cycle of season is repeated year after year.
  • Four seasons, each of three months duration have been recognized in temperate regions.
  • They are spring, summer, autumn and winter.
  • In our country, we have three distinct seasons which are summer, winter and monsoons.
  • The Indian Meteorological Department has recognized four main seasons.
  • They are
    • Cold weather season (December to February.)
    • Hot weather seasons (March to May)
    • Advancing monsoon season or rainy season (June to September.)
    • Retreating monsoon season (October to November.)
  • The rays of the sun are more or less direct on the equator throughout the year. Hence, equatorial regions experience the same temperature all the year round. Therefore, seasons are insignificant on or near the equator.
  • Near the coast, the oceanic influence reduces the seasonal variations.
  • In the polar regions, there are only two seasons i.e. long winter and short summer.

Climate

  • The average weather conditions, prevalent from one season to another in the course of a year, over a large area is known as climate.
  • The average of these weather conditions is calculated from the data collected for several years (about 35 years) for a larger area.
  • Rajasthan, for example, experiences hot and arid climate, Kerala has tropical rainy climate, Greenland has cold desert climate and the climate of Central Asia is temperate continental.

Climate of a region is considered more or less permanent.