7th Geography



1.The Greek world klimal’ refers to ——–


2. The temperature on the earths surface decrease at the rate of 6.5oC for every 1000 meter.

3. EI Niño means the ————— in Spanish

Christ child.

4. The —————- is a metropolitian are which is significantly warmer than its surrounding areas.

Urban heat Island

5. The——— is the boundary between the troposphere and stratosphere.


6. The equational low-pressure belt is called a ——-

A battle of calm

7. The air in horizontally motion is called a—–


8. The name of the local wind which blows over that desert is—Loo

9. The study of the science of lightning is called ——–


II. Choose the correct answer:-

1. In the tropical regions paddy is a major crop.

2. During nino period the temperature rises rapidly once in three to eight years along the coast of a peru and equadar.

3. The difference between maximum and minimum temperature of the day is called diurnal range of temperature.

4. Barometer is an instrument used to measure the atmospheric pressure.

5. Subtropical high-pressure belt is called horse latitudes.

6. In Ionosphere layer the sun’s rays is ionized.

7. Cumulus clouds are associated with rainfall, thunder and lightning.

8. Convectional type of rainfall is also called 4’O’ clock rainfall.

9. The average air pressure at the sea level is 1013 millibars.

10. The nimbus clouds are vertical clouds

Match the following

1. Global Warming — human influences

2.Thermometer —- instrument measuring temperature

3. Anemo meter — instrument showing of wind

4. Eye of the cyclone —- vaccum

5. Thunderstorms — weather factory.

IV. Write short answers:

1. Differentiates weather and climate:


Refers to the physical state of the atmosphere within 24 hours destroyed by weather elements


Climate is commonly defined as the weather averaged over a long period of time and over a large area.

The standard averaging period is 30 years

2. What are the advantages and disadvantages of meeting warm of and cold ocean currents.


· The meeting places of warm and cold ocean currents are the areas of major fishing grounds.

· Because the conditions are suitable for the formation of dense fog and low clouds.


· At that same time these areas are dangerous for shipping as they are suitable for the formation of dense fog and low clouds.

3. List the mechanisms by which the earth receives the solar radiation.

· Radiation in the atmosphere.

· Conduction overland.

· Convection in the water bodies.

4. What are the scales to measure Temperature?

· Celsius.

· Fahrenheit.

· Kelvin.

5. Differentiate Isobars and isohyets.


The imaginary lines joining different places with the same pressure on a map are known as isobars.


The imaginary lines that join different places having same amount of rainfall on a map are known as Isohyets.

6. Define ferrels law:-

· All moving objects including winds and oceans currents tend to get deflected towards right in the northern hemisphere and left in the southern hemisphere due to the rotation of the earth.

· This changeless principle is called the ferral1s law (or) coriollis force.

7. What are planetary winds?

· The winds that blow from a particular direction throughout the year are known as the planetary winds.

8. What is lightning? How they formed?

Lightning can be defined as the atmosphere discharge of electricity.

It is formed by the meeting of the positive and negative charges in the clouds containing ice.

9. What is weather factory?

· The thunderstorms are Accompanied by many weather element, meteorologists refer them to as weather factory.

· The formation of thunder Stroms ranges from 4 to 20 km.

10. Differeentite equable and extreme type of climate.

Equable climate:-

· The coastal areas experience the cool, wet air from the sea throughout the year which modifies the weather along coast to have uniform weather both in the winter and summer.

· This condition is said to be an equable climate or maritime climate.

Extreme climate:-

· The land absorbs and loses heat quickly an empty experience warm and dry air.

· They are very hot in summer and very cold in winter.

· This condition is said to be extreme type of climate or conditional climate.

V. Brief answers.

1. What are the factors determining weather and climate?

Explain EL nino.

The following factor determine weather and climate.

· They are latitude, altitude, ocean currents from the sea, direction of prevailing winds.

EL Nino:

· EL Nino is one of the reasons for the failure of the monsoon.

· In Spanish EL nino means ‘The Christ child’.

· It is formed around Christmas time and continues for a six months.

· During this period, once in five or six years the temperature rises rapidly. A low pressure system is formed along the coast of Peru and Equador.

· It attracts winds from all directions.

· So, the trade winds become very weak over the pacific Ocean and Indian ocean.

· These winds are deflected and cause a prolonged dry period in India.

· The other effects of EL nino are experienced in other areas too.

· They are bush fire and drought in Australia, famine in Indonesia and forest fires in Brazil and south East Asia.

2. What are the heat zones of the earth? Explain any one of them with a neat diagram.

· The temperature reduces with increasing latitude.

· Based on this, the earth is divided into Torrid, Temperate, Frigid zones.

Torrid zone:

· The places between the tropic of cancer and the tropic of capricorn.

· It receives vertical Sun rays all round the year.

· So they are hotter than the other zones.

3. What is called land breeze and sea breeze? With a Diagram.

Land breeze:

· During the night time the land becomes cooler than the adjoining of water bodies. So, there is a high pressure on the land and the low pressure on the water body.

· Hence cool dry breeze blows from the land towards the sea in the early morning.

Sea breeze:

· During the daytime the land becomes warmer than the adjoining of water bodies.

· As a result, a low pressure on the land and a high pressure on the water body formed.

· This leads to the cool wet breeze from the sea to blow towards land in the late evening.

5. What are the types of rainfall? Explain conventional rainfall.

Rainfall is classified into 3 types namely,

a. Convectional rainfall

b. Relief or Orographic rainfall

c. Cyclonic rainfall.

Convectional rainfall:

· The equatorial regions receive vertical sunrays and hence become hot.

· The hot air temperature reduces gradually, the air gets cooled and formed clouds.

· When the clouds reach the dew points, they cause rainfall.

· This is known as convectional rainfall. It is known as convectional thunder and lightning.

· Usually it occurs around 4’o clock rainfall.

Orographic rainfall (or)Relief:

· The winds that below from the sea contain a lot of moisture.

· When the moisture laden winds from the sea climb the hill slope the winds become cool causing heavy rainfall in the wind- ward side.

· Then these winds descend on the lee ward side of the mountains and cause low to no rainfall.

Cyclone rainfall.

· The warm air from the hot area is further heated and moves upward.

· Hence a low pressure area is developed and attracts air from the adjacent high pressure areas.

· The raising air gets cooled and condensation take place.

· This brings heavy rainfall in the low pressure areas. Eg. Coast of Tamil Nadu, Andhra Pradesh and Orissa.

8.Write a note on Thunderstroms?

· Thunderstroms are produced by cumulonimbus clouds.

· They are usually of short duration. They are accompanied by lightning, thunder, strong wind guests. Heavy rain and sometimes hail.

· The thunderstorms are accompanied by many weather elements, meteorologists refer them to as weather factories.

The formation of the Thunderstroms ranger from 4 to 20 km.

9. What are clouds? Explain any one of them.

· A cloud can be defined as a mass of small water droplets or ice crystals formed in the atmosphere.

· Clouds are formed by very minute suspended water particles present in the atmosphere.

· According to the shape and altitude the clouds are classified as cirrus, stratus, cumulus and nimbus.

Nimbus clouds:-

· These are vertical clouds. They are thick dark on gray or black clouds.

· They are vertical clouds.

· They cause continuous rainfall so they are known as storm or rain clouds.

10. What are the layers of Atmosphere? Explain any one of them with a diagram.

· The atmosphere of the earth is divided into four major layers.

· They are Troposphere, stratosphere, Ionosphere, Exosphere.


· The exosphere is the upper most layer of the atmosphere.

· The main gases within it are the lightest gases mainly hydrogen and helium.

· This layer is sometimes considered a part of outer space.