Engineering Questions with Answers - Multiple Choice Questions
Environmental Science MCQ – Greenhouse Gases – 1
By how much has atmospheric carbon dioxide concentration increased ever since the Industrial Revolution?
Explanation: Due to excessive combustion of fossil fuels, the carbon dioxide concentration shot up from 280ppm during 1750 to nearly 400ppm recently.
Which is the most abundant greenhouse gas in the atmosphere?
a) Carbon dioxide
b) Water vapour
Explanation: Water vapour also helps in trapping sun’s heat energy and thereby serves as the most abundant greenhouse gas.
What does the phrase “anthropogenic CO2 emissions” mean?
a) Human made CO2 emissions
b) Industrial CO2 emissions
c) Natural CO2 emissions
d) All of the mentioned
Explanation: The word “anthropogenic” stands for environmental impact due to human activity.
Which of the following is the largest sink for carbon dioxide gas?
c) Ice sheets
Explanation: Carbon dioxide dissolves in water as not only gas but also in the bicarbonates form. Therefore, ocean is one of the major sinks for carbon dioxide.
Apart from Earth, which other celestial body(s) exhibits greenhouse gas effect?
d) All of the mentioned
Explanation: Titan, Mars and Venus contain several greenhouse gases in their atmosphere and exhibit greenhouse effect.
Which of the following bodies in the solar system has anti-greenhouse effect?
Explanation: Titan also exhibits anti-greenhouse effect. The haze, constituting organic molecules, is not very efficient in trapping infrared radiations and thereby reduces the temperature by 9 K.
Which of the following radiations of the sun do greenhouse gases trap?
a) Visible radiations
b) Infrared radiations
c) UV radiations
d) All the radiations
Explanation: Greenhouse gases trap the infrared radiations from the sun and reflect it back to the Earth’s surface thereby heating up the planet.
What does “airborne fraction” with respect to greenhouse gases indicate?
a) Amount of greenhouse gases that are released into air due to industrial process
b) Proportion of greenhouse gases in air to all the other atmospheric gases
c) Proportion of greenhouse gas emission that remain even after a specified time
d) None of the mentioned
Explanation: The airborne fraction (AF) indicates the proportion of GHG emissions that remain after a given time.
Clouds help in cooling down the planet and do not contribute to greenhouse effect.
Explanation: Clouds can absorb infrared radiation as well as emit them and hence contribute to greenhouse effect.
What does GWP in the context of greenhouse gases indicate?
a) Global Warming Parameters
b) Gradual Warming Pattern
c) Global Warming Patterns
d) Global Warming Potential
Explanation: Global warming potential indicates the heat trapped by a greenhouse gas over 20, 50 or 100 years in terms of equivalent heat trapped by carbon dioxide over the same period of time.
What is the GWP of methane over a time period of 20 years?
Explanation: According to IPCC methane which has a 12.4 years lifetime, has a GWP of 86 over a period of 20 years.