Atmosphere 8th Notes KSEEB Social Science
→ Atmosphere is a layer of gases, dust particles and water vapour surrounding the earth.
→ Atmosphere, layer of gases forms protective boundary between the entire space and the earth’s surface.
→ Atmosphere traps heat and makes Earth a planet for all the living organisms.
→ Layers of atmosphere divided are into 5 important layers on the basis of its characterstics.
→ Tropophere, startosphere, mesosphere, themosphere, exosphere, are the 5 important Layers of atmosphere.
→ Weather conditions of a place is influenced by various elements such as temperature, pressure, wind, humidity, clouds, rainfall etc.
→ The sun is the main source of energy to the earth.
→ Temperature is recorded by an instrument called “thermometer”.
→ Temperate zone, torrid some, temperate zone, frigid zone etc are the important temperate zones.
→ Air has weight and it exerts pressure. It is called atmospheric pressure.
→ Air pressure is measured by Baromerter.
→ Wind is the horizantal movement of the air on the surface of the earth.
→ Wind blows on the earth due to rotation of the earth and difference in pressure. Anemometer’ is used to measure the speed of the wind.
→ Planetary winds, seasonal winds, local winds, cyclones and anticyclones, are the types of winds.
→ Planetary winds called permanent winds, they blow more or less in the same direction throughout the year.
→ The trade winds in the nothern hemisphere blow from Northeast to south west direction and in the southern hemisphere they blow, from south east to northwest.
→ Westerlies Anti-trade winds are called ‘Roaring forties’.
→ Polar winds are called as easterlies. These are the cold dry winds blowing from the polar ice- caps.
→ Cyclones and anti cyclones blow due to great variation in pressure. These are temporary but sometimes dangerous and destructive.
→ Humidity is the amount of water vapour or moisture present in the air.
→ Humidity is measured by using an instrument called Hydrometer or psychrometer. Clouds is a mass of small water drops or ice crystals formed by the condensation of the water in the atmosphere.
→ Stratus, cumulus, cirrus, Nimbus clouds.
→ Precipitation in two form of water droplets is called rainfall.
→ Conventional Rainfall, or graphic rainfall, Cyclonic rainfall etc.
→ The atmospheric conditions of a smaller area at a particular time is called ‘weather’. Climate is the average conditions of the atmosphere over a long period of time of larger area.