3. WHAT IS WEATHER ?
Weather is the state of the atmosphere at a given place and at a given
time.
4. about weather :-
The study of weather and its elements is known as meterology.
Weather refers to a particular station.
Weather may change within a short interval of time.
Some examples of weather is:-
sunshine
rain
cloud cover
winds
hail
snow
sleet
freezing rain
flooding
blizzards
ice storms
thunderstorms
15. World’s pressure belts
The unequal heating of the earth and its atmosphere and the rotation of the earth
are the main two factors which are responsible for the formation of pressure belts in
the world.
The types of permanent pressure belts are:-
Equatorial low pressure belt (doldrums)
Sub-tropical high pressure belt
Sub-polar low pressure belt
Polar high pressure belt
16. humidity
The amount of water vapour present in the air is called humidity.
The types of humidity are:-
Absolute humidity
Relative humidity
17. precipitation
The process through which water from the atmosphere falls down on the earth is
called precipitation.
Types of precipitation:-
Rain
Dew
Hail
Snow
18. wind
Wind blowing from the east is called an easterly wind and wind blowing from the
west is called westerly wind.
Types of winds are :-
Air moves from high pressure areas to low pressure areas . Such a horizontal movement
of air is called the wind.
Planetary winds
Periodic winds
19. clouds
A clouds is a large collection of very tiny droplets of water or ice crystals.
Classification of clouds:-
High clouds
Middle clouds
Low clouds
20. Weather instruments
A weather instrument is any device that measures weather related conditions
Types of weather instruments:-
Thermometer - Temperature is measured with the help of a THERMOMETER.
Rain gauge – Rainfall is measured with the help of RAIN GAUGE.
Hygrometer – Water vapour is measured with the help of HYGROMETER.
Anemometer and wind vane – Wind’s speed is measured with the help of
ANEMOMETER and wind’s direction is measured with the help of WIND VANE.
Barometer – Atmospheric pressure is measured with the help of BAROMETER.