Tag: pollution and its effects

Questions Related to pollution and its effects

High concentration of greenhouse gases has resulted in maximum rise of atmospheric temperature in 

  1. Tropic region

  2. Middle latitude

  3. Polar region

  4. Temperate region


Correct Option: C
Explanation:
Increases in the level of greenhouse gases has led to considerable heating of earth leading to global warming. During the past century, the temperature of earth has increased by $ 0.6  $, most of it during the last three decades. Rise in temperature is slight in tropics, moderate in middle latitudes and maximum in polar regions. It will led to melting of polar ice caps as well as of other places like the Himalayan snow caps.
So, the correct answer is 'Polar region'.

If there is no greenhouse effect, then the average temperature at surface of earth would have been 

  1. $ 15 $

  2. $ -18 $

  3. $ -6 $

  4. $ 10 $


Correct Option: B
Explanation:
Greenhouse gases like $ { CO } _{ 2 }, { CH }{ 4 } $ and $ { CFC } _{ s } $ are essential for keeping the earth warm and hospitable. They prevent a substantial part of long wave radiations emitted by earth to escape into space, but these gases radiate a part of this energy back to the earth. This phenomenon is called greenhouse effect. Because of green house effect, the mean annual temperature of earth is $ 15. $ In its absence, it will fall to $ -18. $
So, the correct answer is '$ -18. $'

Which of the following is correct regarding 'El Nino' effect?

  1. Temperature rise leads to odd climatic changes

  2. Cutting down the use of fossil fuels

  3. Planting more trees

  4. Slowing down the growth of human population


Correct Option: A
Explanation:
The rise in temperature due to global warming is leading to deleterious changes in the environment and resulting in odd climatic changes like EL Nino effect. El Nino effect is the abnormal warming of surface ocean water. It affects the weather in large parts of the world. Moisture carrying capacity of air will increase. Pattern of air-mass movement will change. Precipitation will increase at higher latitudes both in summer and winter and in southern as well as Eastern Asia in summer. Frequency of droughts and floods  will increase. Threat to human health will increase in tropical and subtropical countries due to changed ranges of disease vectors and water borne pathogens.
So, the correct answer is 'Temperature rise leads to odd climatic changes'.

Denitrification is caused by

  1. Pseudomonas

  2. Nitrobacter

  3. Nitrosomonas

  4. Azotobacter


Correct Option: A
Explanation:
Denitrification is the process of degradation of fixed nitrogenous compounds to free nitrogen which is released back to the atmosphere. It is performed by several bacteria like Pseudomonas which utilize nitrate to form nitrite in a process called reduction. Nitrite is further reduced to nitric oxide then to nitrous oxide and then nitrogen gas. This process reduces the fertility and ultimately the agricultural productivity decreases.
Thus, the correct answer is option A.

Warm ocean surge of Peru current recurring every 5-8 years or so in the East Pacific of South America is widely known as.

  1. Gulf Stream

  2. Aye Aye

  3. El Nino

  4. Mangox


Correct Option: C
Explanation:

EI Nino describes the unusual warming of surface waters in the eastern tropical pacific ocean. This occurs when the normal trade winds weaken or get reverse which lets the warm water flow in the eastern Pacific instead towards the west. Thus it forms oscillation in the ocean-atmosphere.

So,the correct answer is option C.

Which of the following cause green house effect?
(i) Deforestation
(ii) Emission of gases from factories
(iii) Melting of polar ice

  1. Only (i) and (ii)

  2. Only (i) and (iii)

  3. Only (ii) and (ii)

  4. (i), (ii) and (iii)


Correct Option: A
Explanation:
Deforestation is removal, decrease or deterioration of forest cover of an area. It causes the change in climate, floods, soil erosion, siltation, cyclones, drought, desertification and increased level of carbon dioxide (greenhouse gas) in the atmosphere. Greenhouse gases like carbon dioxide and CH$ _4$ that are also released from factories cause green house effect.

Which of the following is not a greenhouse gas?

  1. $N _2O$

  2. CFC

  3. $O _3$

  4. $SO _2$


Correct Option: D
Explanation:

The gases which are transparent to solar radiation but retain and partially reflect back long wave heat radiations are called greenhouse gases. The various greenhouse gases are carbon dioxide, methane, chlorofluorocarbons and nitrous oxide. Other gases of minor significance are water vapour and ozone. Thus, the correct answer is option D.

Which of the following is a green house gas?

  1. CO

  2. CO$ _2$

  3. H$ _2$

  4. N$ _2$


Correct Option: B
Explanation:

Carbon dioxide is normally a non-polluting gas and is required for the normal process of photosynthesis by green plants. However, higher atmospheric concentrations of carbon dioxide due to the high rate of emission from the vehicle and deforestation leads to heating of earth and global warming.

So, the correct answer is option B.

Increase of temperature due to scattering of energy is by ozone, CO$ _2$ and water vapour, is known as

  1. Radioactivity

  2. Ozone effect

  3. Solar reaction

  4. Greenhouse effect


Correct Option: D
Explanation:

Global warming is the overheating of the earth due to the increased concentration of greenhouse gasses. Greenhouse gasses generally traps the radiations of the earth which leads to increase in the temperature of the earth and global warming. The greenhouse gasses includes water vapor, carbon dioxide, methane, nitrous oxide, and ozone. 

Checking of radiating heat by atmospheric dust, O$ _3$, CO$ _2$ and water vapours is

  1. Greenhouse effect

  2. Solar effect

  3. Ozone layer effect

  4. Radioactive effect


Correct Option: A
Explanation:

The concentration of oxides increases due to the high rate of emission from the vehicle and other human activities like deforestation. The oxides form a layer which traps solar radiation to escape the earth atmosphere which leads to global warming.

So, the correct answer is option A.