If you are looking for TN Board Class 8 Geography Unit 2 Weather and Climate, then you are at the right place. Here we are providing solutions as well as additional QA / Important Notes.
I Choose the correct answer
Earth’s atmosphere contains about percentage of nitrogen and oxygen.
- 78% and 21%
- 22% and 1%
- 21% and 0.97%
- 10% and 20%
……….is generally defined as the average conditions of the weather of a place or a region.
- Earth
- Atmosphere
- Climate
- Sun
The earth receives energy from .
- Current
- Electro magnetic radiation
- Waves
- Heat
Which one the following represents places with equal amount of rainfall
- Isotherm
- Isohel
- Isobar
- Isohytes
……….is used to measure the humidity.
- Anemometer
- Barometer
- Hygrometer
- Thermometer
II Fill in the blanks
- _____________ refers to the condition of atmosphere for a short period of time.[weather]
- The scientific study of weather is called ____.[meterology]
- The highest temperature ever recorded on the earth is ______________.[56.7°C (134°F)]
- _____________ is a ratio between the actual amount of water vapour and the maximum amount of water vapour the air can hold.[Relative humidity]
- ____________ and_____________ are measured by anemometer and wind vane respectively.[Wind speed and wind direction]
- _________ are imaginary lines which connect the same temperatures of different places.[Isotherms ]
III Match the following
- Climate – Locating and Tracking Storms
- Isonif – Cyclone
- Hygrometer – Equal Snowfall
- Radar – Long Term Changes
- Low Pressure – Humidity
Answer
- Climate – Long Term Changes
- Isonif – Equal Snowfall
- Hygrometer – Humidity
- Radar – Locating and Tracking Storms
- Low Pressure – Cyclone
IV State whether the following statements are True or False
- The atmosphere is a layer of gases surrounding the earth.[True]
- The Scientific study of weather is called Climatology.[False]
- Isohel refers equal sunshine.[True]
- Humidity is calculated by Aneroid Barometer.[False]
V Answer briefly.
Define ‘weather’.
Weather refers to the day-to-day conditions of the atmosphere at a specific place, including factors such as sunshine, temperature, cloud cover, wind, fog, air pressure, humidity, and precipitation. It is concerned with short-term changes, ranging from a day to a week or slightly longer.
What is insolation?
Insolation is the incoming solar radiation that reaches the Earth’s surface. It is the primary source of energy that heats the Earth and its atmosphere, influencing weather and climate patterns. The amount of insolation received at a place depends on factors such as the angle of the sun’s rays, the length of the day, and atmospheric conditions.
What is meant by atmospheric pressure?
Atmospheric pressure is the force exerted by the weight of the air above a given area on the Earth’s surface. It is measured in units such as millibars (mb) or kilograms per square centimeter (kg/cm²). Atmospheric pressure decreases with altitude and varies with weather conditions. It is measured using instruments like barometers.
Write a short note on “Planetary winds”
Planetary winds are large-scale wind patterns that blow consistently in the same direction across the globe. They are also known as permanent winds and include the Trade Winds, Westerlies, and Polar Easterlies. Trade Winds blow from the subtropical high-pressure areas towards the equatorial low-pressure areas. Westerlies blow from the subtropical high-pressure areas towards the subpolar low-pressure areas in both hemispheres. Polar Easterlies blow from the polar high-pressure areas towards the subpolar low-pressure areas. These winds are driven by the Earth’s rotation and the unequal heating of the Earth’s surface.
What are “Isolines”?
Isolines are imaginary lines drawn on maps to connect points of equal value of a certain variable. They help in visualizing and analyzing spatial patterns and distributions. Common types of isolines include:
- Isotherms: Lines connecting points of equal temperature.
- Isobars: Lines connecting points of equal atmospheric pressure.
- Isohyets: Lines connecting points of equal rainfall.
- Isohels: Lines connecting points of equal sunshine.
- Isonifs: Lines connecting points of equal snowfall.
