Clouds

Total Questions: 7

1. Clouds are the result of- [Uttarakhand P.C.S. (Pre) 2016]

Correct Answer: (d) Condensation
Solution:Clouds are formed as a result of the process of condensation. Conversion of water in the gaseous state to a liquid or solid state is called condensation. clouds are a collection of very tiny droplets of water or ice crystals formed by condensation of water vapour in the atmosphere.

2. Which of the following cloud is responsible for highly intense rain? [Jharkhand P.C.S. (Pre) 2003]

Correct Answer: (b) Cumulonimbus
Solution:Cumulo-nimbus clouds are highly diversified and dense in nature. These are a high possibility of rain, hails and thunderstorms associated with these clouds. Cumulonimbus cells usually dissipate within an hour once starts falling, making for short-lived, heavy rain.

3. Highest altitude clouds are - [U.P. Lower Sub. (Pre) 2009]

Correct Answer: (d) Cirrostratus
Solution:Cirrostratus are the highest altitude clouds. High-level clouds occur above about 20,000 feet and are given the prefix "cirro.".

Due to cold tropospheric temperatures at these levels, the clouds primarily are composed of ice crystals, and often appear thin, streaky, and white (although a low sun angle. e.g., near sunset, can create an array of color on the clouds). Cirrus, Cirrostratus, and Cirrocumulus are the cloud types found here.

4. Consider the following climatic and geographical phenomena: [I.A.S. (Pre) 2002]

1. Condensation

2. High temperature and humidity

3. Orography

4. Vertical wind

Thunder clouds development is due to which of these phenomena?

Correct Answer: (c) 1, 2 and 4
Solution:Thunder cloud is a process of a thunderstorm. In fact, thunderstorms are a local lightning storm that develops in hot, humid tropical areas like India very frequently. The rising temperature produces strong upward rising winds.

These winds carry water droplets upwards, where they freeze(condense), and fall down again. The swift movement of the falling water droplets along with the rising air creates lightning and sound. So it is clear that except Orography, all are related to thunder clouds.

5. During a thunderstorm, the thunder in the sky is produced by the - [I.A.S. (Pre) 2013]

1. meeting of cumulonimbus clouds in the sky.

2. lightning that separates the nimbus clouds.

3. violent upward movement of air and water particles.

Select the correct answer using the code given below

Correct Answer: (d) None of the above
Solution:During a thunderstorm, thunder is the sound caused by a lightning discharge. Lightning heats the air in its path and causes a large over-pressure of the air within its channel.

The channel expands supersonically into the surrounding air as a shockwave and creates an acoustic signal that is heard as thunder. Hence none of the above options is correct.

6. In the context of which of the following do some aurscientists suggest the use of cirrus cloud thinning technique and the injection of sulphate aerosol into stratosphere? [I.A.S. (Pre) 2019]

Correct Answer: (a) Creating the artificial rains in some regions
Solution:Scientists are researching climate engineering to reduce global warming. A major technique related this is the cirrus cloud rarefaction technique. Cirrus clouds are icy crystals of water vapour, which prevent heat reflected from the ground from escaping into other space.

By spraying bismuth triiodide or silver Iodide on these clouds it, become sparse. As a result of their rarefaction, their heat absorption capacity is reduced, due to which the terrestrial radiation will go comparatively more into space and thus the Global Warming will be reduced.

Similarly, under another proposed geoengineering technique, spraying of sulfate aerosols in the stratosphere would create a layer, which would reflect some amount of solar radiation before reaching the Earth's Troposphere, thereby reducing radiation on Earth will be achieved and thus global warming will be reduced.

7. Why are dewdrops not formed on a cloudy night? [I.A.S. (Pre) 2019]

Correct Answer: (b) Clouds reflect back the Earth's radiation.
Solution:The most suitable conditions for dew formation are cler sky, clam air, high relative humidity and cool and long nights. With higher temperature during the day, the water holding capacity of the air increases, due to which the amount of water vapour (humidity) in the air increases.

On the con- trary, when the temperature becomes very low at night, the water-holding capacity of the air decreases due to which more water vapour from the saturated air condenses in the from of drops on the cold surface, which is called 'dew'.

But when clouds cover the night sky, they reflect back Earth's radition, keeping the air and surface warm. Due to this the diurnal temperature difference is less and  does not form.