The document discusses air temperature and factors that influence it. It defines air temperature as a measure of the kinetic energy of air molecules, with higher temperatures indicating faster molecule movement. Key points: - Air temperature is dependent on the amount of heat gained or lost at the earth's surface from solar radiation, varying between day and night as well as by location. - Several factors influence air temperature, including latitude, altitude, distance from bodies of water, cloud cover, humidity, wind, and land surface type. - Temperature is typically measured in degrees Celsius, Fahrenheit or Kelvin. Inversions can occur where warmer air sits above cooler surface air, acting as a lid and limiting convection.

1. UNIT - 5
AIR TEMPERATURE
SUBMITTED BY
DIVYA MALAKAR

2. AIR TEMPERATURE
• Air temperature is a measure of how hot or cold
the air is.
• It is the most commonly measured weather
parameter.
• Temperature describes the kinetic energy, or
energy of motion, of the gases that make up air.
• As gas molecules move more quickly, air
temperature increases.
• Unit of measurement DEGREE, KELVIN and
FEHRENHEIT

3. • Air temperature is dependent upon the amount of heat gained or
lost at the earth’s surface or any other surface with which air has
recently been in contact.
• Heat exchange at surface varies between night and day, with the
season, latitude , time of year, influenced by cloud cover.
• DURING DAY- surfaces are heated by solar radiation, the air nearest
to the ground acquires higher temperature.
• AT NIGHT- the ground losses much heat by radiation and after
sunset its temperature falls below that of air. The direction of flow is
reversed : from air to the ground . The lowest air becomes cooler.

4. TEMPERATURE SCALES
• Celsius
• water freezes at 0o
• water boils at 100o
• Fahrenheit
• water freezes at 32o
• water boils at 212o
• Kelvin
• no molecular motion at 0 K
• water freezes at 273 K
• water boils at 373 K

5. IMPORTANCE OF AIR
TEMPERATURE
AIR Temperature Affects:
• the rate of evaporation
• relative humidity
• wind speed and direction
• precipitation patterns and types, such as whether it will rain,
snow, fog or sleet.

6. FACTORS THAT INFLUENCE AIR
TEMPERATURE
• Latitude
• Altitude
• Distance From The Sea
• Ocean Currents
• Humidity
• Cloud Cover
• Aspect
• Types Of Land Surface
• Wind, Land & Water
• Atmospheric impurities
• Landscape and urban areas

7. LATITUDE
HIGHER TEMPERATURE AT OR NEAR EQUATOR.
LOWER TEMPERATURE IF AWAY FROM THE EQUATOR ,
TOWARDS NORTH & SOUTH POLE.
REASON:
• The angle at which the sun's rays strike the earth affects the
air temperature.
• At equator vertical sun rays strikes at 90 ° resulting more heat
gain .
• Away from the equator, due to earth curved surface, vertical
sun rays strikes at an angle less than 90 ° resulting less heat
gain thus lower air temperature.

8. ALTITUDE
Height above the sea level is altitude.
LOW temperature at HIGH ALTITUDE ex. At the mountain.
HIGH TEMPERATURE at LOW ALTITUDE for ex. Land surface.
Reasons:
• For every increase in height of 1000M, there is decrease of air
temperature by 6.5 °c.
• Density of the air decreases with height as the concentration
of gases and water vapor decreases.
• Thus the capacity of air to capture heat decreases with
altitude.

9. Distance from the sea
An inland location is further away from the sea, while a coastal location
is close to the sea.The difference in heating of land and water affects
the temperature of places.
The land heats up and cools down more quickly than the sea.
• During the summer, the air over the land heats up quickly, while the
air over the sea remains relatively cool because the sea gains heat
much slower than the land. Onshore winds blow cooler air towards the
land, lowering the summer temperatures of the areas along the coast.
• During winter, the air over the sea remains relatively warm compared
to the air over the land because the sea loses heat slower than the land.
The onshore winds blow warmer air towards the land, raising the winter
temperatures of the coastal areas.

10. MARITIME INFLUENCE
During the winter the sea is warmer than the land and
keep coastal places warmer by moderating the
temperature. but in summer, the sea is cooler than the
land thus it lower the temperature of coastal place.
CONTINENTAL INFLUENCE
Located in the interior of large continents i.e. the sea
does not has effect on them as they are very far in
temperatures.
Due to heating properties of land the inland areas
experiences hotter summers and colder winters, then
coastal regions of the same altitude

11. CLOUD COVER
The amount of clouds in a given area.
Places near the equator has greater amount of cloud cover.
Desert areas where humidity is low has less cloud cover.
 Temperate area with low cloud cover experience larger
difference in day and night temperatures.
 Tropical areas with dense cloud cover, due to high humidity in
the air, experience a smaller difference in day and night
temperatures.

12. Humidity
• The amount of water vapour present in the
atmosphere and it influence the cloud cover in
the sky.
• Greater the amount of humidity higher the cloud
coverage and vice verse.
• Lesser the amount of cloud clover lower the
humidity.

13. WIND AND OCEAN CURRENTS
Wind is the horizontal movement of air from a region of high pressure to a
region of low pressure.
Ocean currents modify the temperature of the winds, which blow over them.
Prevailing winds blowing inland from the sea help to moderate the
temperature of adjacent land masses.
• A wind, which has blown over a cold ocean current, will have its
temperature lowered. Cold ocean currents originate from the Poles and lower
the temperature of the winds, thus lowering the temperature of the coastal
countries they pass through. Amount of rain in those coastal areas decreases.
• A wind, which has blown over a warm ocean current, will have its
temperature raised. Warm ocean currents carry water from the tropics to the
poles and raise the temperature of the winds, thus warming the coasts they
pass through. Amount of rain in those coastal areas increases.

14. ASPECT
• Direction of the mountain slope with respect to the
sun.
• Aspect has more influence in temperate areas
compared to tropical areas.
• The angle at which sun strikes the horizon guides the
influence of the aspect on that region.
• In southern hemisphere the north facing slopes are
warmer than south-facing slopes and vice verse.
TROPICAL AREAS: Sun is high in the sky therefore
aspect is not much important.
TEMPERATE AREAS: The sun is low in the winter , this
will affect the temperature of the slopes that face
north to south.

15. LENGTH OF THE DAY
As the number of hours of daylight increases, the season changes to
summer, resulting in higher temperatures. As the number of hours of
daylight decreases the season changes to winter, resulting in lower
temperatures.
TYPES OF LAND SURFACE
DENCE FOREST
the vegetation cover prevents direct contact of solar radiation with
ground. Thus low air temperature.
IN THE CITY
The materials like concrete absorbs heat during day and retain the
heat at night. Thus affects air temperature directly , generally
increasing air temperature.

16. TEMPERATURE INVERSION
• Temperature inversion , is a
reversal of the normal
behavior of temperature in
the troposphere, in which a
layer of cool air at the
surface is overlain by a
layer warmer air.
( Temperature usually
decreases
with height).
• An inversion acts like a lid,
keeping normal convective
overturning of the
atmosphere from
penetrating through the
inversion.

17. IMPORTANT CAUSES OF
TEMPERATURE INVERSION
1. Radiation Inversion
2. Subsidence Inversion
3. Adjective Inversion

19. Effects of inversion
• It determines cloud forms, precipitation and visibility.
• It act as cap on the upward movement of air from the layers
below. Thus limited convection and diffusion.
• Regions with pronounced low-level inversion, convective
clouds cannot grow high enough to produce showers.
• Visibility may be greatly reduced below the inversion due to
accumulation of dust and smoke particles.
• It affects diurnal variations in temperature.

20. Types of inversion
• Temperature inversion in intermontane valley
• Ground Inversion
• Subsidence Inversion
• Frontal Inversion

21. Types Of Inversion