Greenhouse Effect and Global Warming: Practice Problems and FAQs

During summers, you might have noticed that if a car is parked outside under the sun for sometime, it gets super hot from inside! However, have you ever wondered how this happens? To answer this question, let us ask one more question. Do you know anything about greenhouses? Greenhouses are glass houses used to grow plants, particularly in the winter. The glass panel in a greenhouse lets light in but prevents heat from escaping.

Now, answering the first question, the glass windows of the car, in a similar manner to greenhouse traps heat and does not allow it to escape. 

Did you know that the atmosphere surrounding our planet also serves as a greenhouse? Interesting right? Let’s take a deeper look into it.

Table of Contents

• Introduction to Greenhouse Effect
• Global Warming
• Practice Problems and Greenhouse Effect and Global Warming
• FAQs and Greenhouse Effect and Global Warming

Introduction to Greenhouse Effect

A phenomenon that occurs in a greenhouse inspired the phrase "greenhouse effect." This phenomenon occurs naturally and is responsible for the heating up of the Earth’s surface and atmosphere, even during the night. In the absence of greenhouse effect, the Earth's surface average temperature would have been a frigid –18°C, rather than the current 15°C. 

Heating of the Earth’s Atmosphere

Gases and clouds in the upper atmosphere reflect roughly a quarter of incoming solar energy and absorb some of it but nearly half of it falls on the Earth's surface, heating it, while only a small part is reflected back. Heat re-emitted by Earth’s surface is in the form of infrared radiation and a significant portion of this is absorbed by atmospheric gases (e.g., carbon dioxide, methane, etc.). These gases emit the absorbed heat energy, a large portion of which returns to the Earth's surface, heating it up once more.
This cycle is performed over and over again and thus, causes a greenhouse effect.

Greenhouse Gases

Greenhouse gases are atmospheric gases, mainly carbon dioxide, methane which absorbs the infrared radiations and heat the Earth’s atmosphere. Eventually, these gases are responsible for causing the greenhouse effect. It also includes chlorofluorocarbons (CFCs) and nitrous oxide in small percentages.

There is a misconception that oxygen is a greenhouse gas. However, it is not true because oxygen gas is transparent to infrared radiations, which means it does not absorb infrared radiations. 

Global Warming

Global warming is the phenomenon in which the levels of greenhouse gases increases resulting in significant heating of the Earth. Increase in the level of greenhouse gases has led to considerable heating. The temperature of the Earth has risen by 0.6 degrees Celsius over the last century, with the majority of this increase occurring in the recent three decades. Scientists believe that this rise in temperature is inflicting major changes in the climatic conditions across the world which can have deleterious effects on living organisms. Global warming can lead to droughts, floods, forest fires, cyclones, etc which in turn will affect crop yield and threaten the lives of plants and animals.

Effects of Global Warming

Melting of Polar Ice Caps and Rise in Sea Level

The rise in temperatures are causing negative changes in the ecosystem and strange climatic variations, resulting in greater melting of polar ice caps and other regions such as the Himalayan snow caps. This will result in a rise in sea level that will submerge numerous coastal areas over many years. 

El Nino Effect

In normal conditions, ocean winds blow in such a way that warm surface water is pushed towards the western Pacific, where it borders Asia and Australia. This results in increased precipitation and contributes to increased rainfall around the western pacific regions.

El nino normally happens every 2-7 years during which the warm surface water moves eastward, from the western Pacific to eastern Pacific region. 
This causes a drastic increase in rainfall in the eastern Pacific regions, contributing to coastal flooding and brings droughts to the western Pacific regions. 

El Niño affects the global climate and disrupts normal weather patterns, which as a result can lead to intense storms in some places and droughts in others. Global warming along with El Nino leads to catastrophic effects on the climatic conditions across the globe.

Ways to Control Global Warming

Global Warming Can be Controlled by Taking the Following Measures:

1. Planting trees
2. Reducing fossil fuel use
3. Limiting greenhouse gas emissions into the atmosphere
4. Reducing deforestation
5. Improving energy efficiency
6. Limiting the increase of the human population

Practice Problems of Greenhouse Effect and Global Warming

Question 1. Which gas among the following is not considered a greenhouse gas?

a. Methane
b. Chlorofluorocarbons
c. Oxygen
d. Nitrous oxide

Solution: Greenhouse gases include carbon dioxide, methane, nitrous oxide and chlorofluorocarbons. Oxygen gas is not a greenhouse gas as it does not absorb infrared radiation.
Thus, the correct option is c.

Question 2. Select the incorrect statement regarding the El nino effect.

a. The El Nino effect contributes to increased rainfall around the western Pacific regions.s
b. As a result of the El Nino effect, rainfall increases drastically in eastern Pacific regions, contributing to coastal flooding.s
c. During an El Nino effect, the warm surface water moves eastward, from the western Pacific to eastern Pacific region.s
d. None of the above

Solution: The El Nino effect is an unusual climatic phenomenon that causes exceptional warming of surface waters in the eastern Pacific Ocean every 2 to 7 years. Temperature, the speed and strength of ocean currents, coastal fisheries, and local weather are all affected. Warm surface water is normally carried towards the western Pacific, where it borders Asia and Australia, by ocean winds. Increased precipitation is caused by convection above warmer surface waters, which adds to increased rainfall in the western Pacific.
During an El Nino episode, however, warm surface water from the western Pacific to the eastern Pacific travels eastward along the Equator. In the eastern Pacific, rainfall increases dramatically.
The correct option is b.

FAQs of Greenhouse Effect and Global Warming

Question 1. What is the greenhouse effect?

Answer: Greenhouse effect is a phenomenon in which the clouds and gases present in Earth’s upper atmosphere reflect one-fourth of solar energy falling on it while absorbing some of it. This heats up the Earth’s atmosphere. Additionally, this heat is again re-emitted in the form of infrared rays on the Earth’s surface causing more heat. Thus, the greenhouse effect leads to the heating up of Earth’s surface and atmosphere.

Question 2. Describe the El nino effect.

Answer: The El Nino effect is an unusual climatic phenomenon that causes exceptional warming of surface waters in the eastern Pacific Ocean every 2 to 7 years. Temperature, the speed and strength of ocean currents, coastal fisheries, and local weather are all affected. Warm surface water is normally carried towards the western Pacific, where it borders Asia and Australia, by ocean winds. Increased precipitation is caused by convection above warmer surface waters, which adds to increased rainfall in the western Pacific.

During an El Nino episode, however, warm surface water from the western Pacific to the eastern Pacific travels eastward along the Equator. In the eastern Pacific, rainfall increases dramatically.

Question 3. Name the greenhouse gases.

Answer: Greenhouse gases are methane, carbon dioxide, chlorofluorocarbons and nitrous oxide.

Question 4. Mention four ways to control global warming.

Answer: The four ways to control global warming are as follows:

• Limiting the emission of greenhouse gases
• Planting more trees
•  Reducing fossil fuel use
• Slow down the human population

Question 5. Define global warming.

Answer: Global warming is the phenomenon of significant heating of the Earth’s temperature due to increase in the levels of greenhouse gases in the atmosphere.

Question 6. How does global warming affect the sea level?

Answer: The rise in temperatures due to global waring is causing negative changes in the ecosystem and strange climatic variations, resulting in greater melting of polar ice caps and other regions such as the Himalayan snow caps. This will result in a rise in sea level that will submerge numerous coastal areas over many years. 

Other Related Topic Of Biology

• Water Pollution and its Control