The document discusses the causes of seasons and factors that determine temperatures in different places. It states that the Earth's axial tilt and yearly revolution around the sun cause the seasons. Several factors influence temperatures, including sunlight duration, the sun's angle above the horizon, and the Earth's distance from the sun. Places near the equator have less temperature variation and defined seasons. Higher latitudes experience more extreme seasonal changes with warm summers and cold winters due to variable sun exposure. Within seasons, temperatures fluctuate based on accumulated heat gains and losses.

3. Content :
 Cause of season
 Factors determining the
temperature
 Temperatures in various places

4. Seasons:
 The earth’s equator is at an angle ω of the
plane of its orbit and its axis of rotation keeps
nearly the same direction in space during a
complete revolution.
 Therefore each pole is presented to the sun for
part of the year and turned away from It for
the reminder .

5. Thus the climatic conditions are different at
different periods for the same place on the
surface of the earth.
Four Seasons:
Seasons
Spring
Summer
Autumn
Winter

6. Two main reasons for Seasons :
 The revolution of the earth around the sun.
 The constant inclination of earth’s axis of its
orbit.
The seasonal changes in the temperature depend
on many factors such as:
 The duration of sun’s stay above horizon
 Sun’s meridian altitude
 The distance of the sun from the
earth(147.72million km)
 The intensity of radiation of sun beams
 The absorption of heat by atmosphere and the
amount of heat gained and lost by the earth

8.  In this case sun’s rays strike the surface directly
 So the sun’s rays spread over small area .
 Therefore the heating power is very large
 Temperature is very high .

9.  In this case the sun’s rays strike the surface of
earth obliquely.
 Sun’s rays spread over large area .
 Moreover the rays have to pass through
greater atmosphere .
 Therefore the amount of the received is less.
 So the temperature is low.
 Thus the high temperature is associated with
high meridian altitude of the sun.

12.  For the place in torrid zone the upper transits of the
sun takes place very near the zenith through the year .
 The duration of day and night are not much different
 Such places having hot through out the year and the
seasonal changes are not much conspicuous
Variations are highly marked in greater latitudes
After March 21st the days are longer and so the
amount of the heat received increses.This
continues till June 21st which is the longest day.
Therefore it appears that the longest day is the
hottest day of the year. But this is not the case . It
is because, after the summer solstice though the
amount of heat received decreases, there is already
some accumulated heat gained .This continuous
till the first week of august when the heat gained
and the lost are equal(in 2019 I was occurred on
July 10) .

13.  This explain why the mid summer is hotter
than the mid spring even though the diurnal
path of the sun are identical in the two Seasons.
For similar reasons mid winter is colder than
mid Autumn and December 22nd , the shortest
day is not the coldest day . The coldest day occurs in
the first week of February (in 2019 It was occurred in
January 31) .

15.  In far north latitude the rays of the sun strike very
obliquely and the heating power is weakened which
reduces the mean temperature.
 .But the longer presence of the sun above the horizon
during he summer compensates to some extent the fall
in temperature. Therefore such places have warm
summer.
 On the other hand during the winter the long nights
reduces the temperature to considerable extent which
produces intense cold and thus making the land unfit
for permanent habitation.

17.  In the frigid zone, during the perpetual day the
sun is above horizon for number of days
together
 Since the latitude of the sun is very low, even
during the perpetual day this region is not hot
but during perpetual night It is unbearably
cold.

18. Thank You