Weather is defined as the short term atmospheric conditions of an area defined by factors like temperature, wind, and rainfall. Climate is the weather of an area over a long period of time, usually 30 years or more. Many factors influence climate, including distance from the equator, height above sea level, distance from bodies of water, wind direction, humidity, and rainfall. The world can be divided into heat zones based on temperature - the Torrid Zone near the equator is hot and humid, Temperate Zones in between are mild, and Frigid Zones near the poles are cold.

1. WEATHER AND CLIMATE

2. WEATHER
• Weather is defined as the conditions air temperature, air pressure, wind,
humidity and rainfall in the atmosphere at a given place and time.
• Weather changes every day. It may be hot and dry but tomorrow it may be
rainy and wet.
• The weather conditions in the morning may be different from that in the
evening.
• Changes in weather conditions give rise to seasons. In India we enjoy
three seasons – summer, winter and monsoon.

3. CLIMATE
• The weather conditions that prevail over a large area and for a long period of time is called
climate.
• The climate of a place remains more or less the same, year after year. Different parts of the
world have different type of climate.
• On the basis of the prevailing climatic conditions, the world can be divided into seven
climatic regions:-
• Very hot and wet Hot and wet
• Very hot and dry cool and dry
• Warm and wet Very cold
• Mediterranean

4. WHAT INFLUENCES CLIMATE ?
• Many factors influence the distribution of heat on Earth, thereby affecting the climate. Let
us read about them:-
• Distance from equator
• Height above the sea level
• Distance from the sea
• Direction of winds
• Humidity and rainfall

5. DISTANCE FROM THE EQUATOR
• The rays of the Sun fall on the surface of the Earth. Near the Equator, these rays are vertical
and are spread over a small area.
• As we move away from the Equator and towards the poles, the rays become slanting and
cover a larger area.
• Thus, places near the Equator receive more heat. These places are hotter than those which
are away from the Equator.

6. HEIGHT ABOVE THE SEA LEVEL
• You know that hill stations such as Shimla, Nainital and Ooty are cool even in summers.
• Most peaks in the Himalayas are covered with snow and ice even during summers.
• This shows that places located at higher altitudes, are colder than those at lower altitudes
even if they are situated on the same latitude.

7. DISTANCE FROM THE SEA
• Places near the coast have a moderate climate. It is neither too hot nor too cold here. This
is due to the effect of sea breezes. Water bodies heat up and cool down at a slower rate
than land. In summer, therefore, the sea is cooler than the land.
• Water bodies heat up and cool down at a slower rate than land. In summer, therefore, the
sea is cooler than the land.
• Hence, air over the sea is cooler than that over the land. This cool air, called sea breeze,
blows from sea to land, making the land cooler.
• In winter the opposite happens and the land becomes warmer. Places far away from the
sea do not get sea breezes.
• So they are extremely hot in summers and extremely cold in winters. Such climate is
called extreme climate.
• Let us compare the climatic conditions of Delhi and Chennai. Chennai is located along the
coast while Delhi is located far away from the coast. As Chennai is nearer to the Equator, it
should be hotter than Delhi in the summer season. But this is not so. Chennai experiences
a mild climate throughout the year as it is near the sea coast.

8. DIRECTION OF WINDS
• Winds blowing from hot regions increase the temperature of a place while those blowing
from cold regions decrease the temperature.
• Delhi is hot in summer due to the dry, hot winds that blow from Rajasthan. In winter, cold
winds from the Himalayas make the northern India very cold.
• Winds blowing from the sea make the lands close to the sea cool and moist. Sometimes,
winds bring clouds with them and cause rainfall.

9. HUMIDITY AND RAINFALL
• Moisture or water vapor present in the air is called humidity. Humid air causes rainfall.
Places near Equator are hot and humid and receive a lot of rainfall.
• Air over deserts do not have moisture, so these places receive very little or no rainfall. Very
cold places experiences snowfall.
• The amount of rainfall and the season when it falls also influence the climate of a place.

10. HEAT ZONES
We can divide the Earth into 3 heat zones on the basis on the basis of the difference in
temperature.
They are:-
• Torrid Zone
• Temperate Zones
• Frigid Zones

11. TORRID ZONE
• The Torrid Zone or Tropical Zone lies on both sides of the Equator, between the tropic of
cancer and the tropic of Capricorn.
• The climate is hot and humid throughout the year because direct rays of the Sun fall over
it.

12. TEMPERATE ZONE
• The areas lying between the Torrid Zones and the Frigid Zones in both the hemispheres
are called Temperate Zones.
• It is neither too hot nor too cold here as these are away from the equator and also from
the poles.

13. FRIGID ZONE
• The areas lying between the Arctic Circle and the North Pole in the Northern hemisphere
and that between the Antarctic Circle and the South Pole in the southern hemisphere are
the Frigid Zones.
• This zone receives slanting rays of the Sun. It remains cold throughout the year.