•The weight of air above a given area on the earth’s
surface is called atmospheric pressure or air
pressure.
•The air pressure is measured by Barometer.
•The standard air pressure at sea level is 1013.25mb.
•At the earth’s surface the pressure is 1.03kg.per sq
cm.
•The variation in standard atmospheric pressure is
found both horizontally and vertically.
The average of maximum and minimum
temperatures within 24 hours is called mean
daily temperature [(87oF+73oF)/2=80oF].
• Diurnal range of temperature is the
difference between the maximum and
minimum temperatures of a day.
• Annual range of temperature is the
difference between the highest and lowest
mean monthly temperatures of a year.
• The distribution of temperature is shown by
means of Isotherms. Isotherms are
imaginary lines which connect the same
temperatures of different places.
•To understand the importance of weather
and climate
•To learn about the nature of the elements of
weather and climate.
•To know the instruments used for
measuring weather elements
•To be able to recognize the kind of weather
and climate of a place
•Earth's atmosphere is a layer of gases
surrounding the planet earth and retained by
the earth's gravity.
•It contains about 78% nitrogen, 21% oxygen,
0.97% argon, 0.03% carbon dioxide and
0.04% trace amounts of other gases and
water vapour.
Weather is the day today conditions(state) of the atmosphere at
any place as regards sunshine, temperature, cloud cover, wind
fog condition, air pressure, humidity, precipitation and such
other elements.
• It refers to short periods like a day, a week, a month or a little
longer and as such the weather changes from time to time in a
day and one period to the other in an year.
• In the morning the weather might be sunny with a clear sky in a
place and evening there might be clouds and rain. Similarly the
weather is cool in winter and hot in summer.
• Scientific study of weather is called Meteorology
• e.g. cricket match have been postponed due to bad weather etc.
The average of maximum and minimum
temperatures within 24 hours is called mean
daily temperature [(87oF+73oF)/2=80oF].
• Diurnal range of temperature is the
difference between the maximum and
minimum temperatures of a day.
• Annual range of temperature is the
difference between the highest and lowest
mean monthly temperatures of a year.
• The distribution of temperature is shown by
means of Isotherms. Isotherms are • Rain is a liquid water in the form of droplets
that have condensed from atmospheric water
vapour and then become heavy enough to fall
under gravity.
• Rain is a major component of the water cycle
and is responsible for depositing most of the
fresh water on the Earth.
• It is the source of water for all purposes.
• There is a close relationship between the
temperature and rainfall distribution.
• Generally rainfall is high in the equatorial
region and decreases gradually towards poles.
• Rainfall is measured by Raingauge.
imaginary lines which connect the same
temperatures of different places.
8th class social Weather and Climate PPT EM DOWNLOAD
•The weight of air above a given area on the earth’s
surface is called atmospheric pressure or air
pressure.
•The air pressure is measured by Barometer.
•The standard air pressure at sea level is 1013.25mb.
•At the earth’s surface the pressure is 1.03kg.per sq
cm.
•The variation in standard atmospheric pressure is
found both horizontally and vertically.
• Humidity refers to the degree of water
vapour present in the atmosphere in
gaseous form in particular time and place.
• It ranges from 0-5 percent by volume in
atmosphere.
• Climatically it is an important constituent
of the atmosphere and its quantity
depends on the level of temperature.
• So, the level of humidity decreases
towards poles from equator.
• The horizontal movement of air is called
wind.
• Vertical movement of air is said as air
current.
• The winds move from high pressure to low
pressure.
• Unlike other elements a wind is made up
of a series of gusts and eddies which can
only be felt and not seen.
• Winds get their name from the direction
from which they blow i.e, wind blows from
south west is called southwest wind.
• Meteorologist measures wind direction using
wind vane or weather cock.
• Wind speed is measured by anemometer.
• Wind rose is a diagram used to depict the
direction and periods (No. of days) of
prevailing winds on map.
• Meteorograph or triple register is an
instrument which records wind speed and
direction, sunshine and precipitation.
•It also provides graphic representation.
• Rain is a major component of the water cycle
and is responsible for depositing most of the
fresh water on the Earth.
• It is the source of water for all purposes.
• There is a close relationship between the
temperature and rainfall distribution.
• Generally rainfall is high in the equatorial
region and decreases gradually towards poles.
• Rainfall is measured by Raingauge.
8th class social Weather and Climate PPT TM DOWNLOAD
•The weight of air above a given area on the earth’s
surface is called atmospheric pressure or air
pressure.
•The air pressure is measured by Barometer.
•The standard air pressure at sea level is 1013.25mb.
•At the earth’s surface the pressure is 1.03kg.per sq
cm.
•The variation in standard atmospheric pressure is
found both horizontally and vertically.
The average of maximum and minimum
temperatures within 24 hours is called mean
daily temperature [(87oF+73oF)/2=80oF].
• Diurnal range of temperature is the
difference between the maximum and
minimum temperatures of a day.
• Annual range of temperature is the
difference between the highest and lowest
mean monthly temperatures of a year.
• The distribution of temperature is shown by
means of Isotherms. Isotherms are
imaginary lines which connect the same
temperatures of different places.
•To understand the importance of weather
and climate
8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT8th class social Weather and Climate PPT
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