Questions & Answers on Global Warming/Ozone Depletion

1) What causes of Enhanced Greenhouse Effect / Increased emission of Greenhouse gases?

It is due to the increase in Human activities such as

Burning of fossil fuels, Burning of forest increases Carbon Dioxide (how? > lesser trees available to take in Carbon Dioxide to photosynthesis and therefore it increases CO2)
Increased raising of livestock > Increased decomposition of Organic Waste, Increased agriculture (water in rice fields) and increased no. of swamps causes an increase in Methane
Too much of burning of solid waste and excessive use of chemical fertilizer causes an Increase in Nitrous Oxide
Increase amount of man-made chemicals used in some aerosol sprays, air-conditioners and refrigerators increases the amount of CFCs. This also increases Ozone depletion.

2) Does the extend of Global Warming change at various parts of the Earth?

No, The extent of Global Warming is greater at the north and south poles. At the poles, about 80-90% of Sun's rays are reflected back into space by the ICE (Glaciers). Now with Global Warming and Ozone Depletion, increased melting of ice reduces the amt of Sun's rays being reflected back into space. The increase in melting also results in an increase to the amount of water in the Ocean. Thus the greater the water body (Ocean) the more heat from the Sun will be absorbed.... leading to an Increases in Temperature = Increase in melting of ice at the Poles.... The Cycle repeats. Therefore in the other parts of the Earth, the extent would differ as the presence of the amount of ice is different.

3) What measures can you as an individual take to reduce Global Warming?

I can help to reduce emissions of greenhouse gases through various means such as Car pull, using more public transportation, by using more energy efficient appliances and by getting licensed agents to dispose off any refrigerators or air-conditioners.

4) What are some measures that Government can take to reduce Global Warming?

Government can encourage using alternate source of energy such as hybrid cars. They can also Enforce certain laws and regulations to reduce the emission of Greenhouse gases. For example in Singapore, we have laws to control the amount of gases emitted by vehicles. They can also encourage using products that are more energy-efficient. For example in Singapore manufacturers of refrigerators and air-conditioners may apply to Singapore Environment Council to have their products labelled for energy efficiency. Government can also ban the use of CFCs. For example in Singapore, since 1995 all new cars imported in are required by law to be equipped with CFC-free air-conditioning systems.

5) Describe the International efforts used to reduce Global Warming.

Many countries and international agencies work together to monitor and manage the Global Warming problems which were responded by 

> Kyoto Protocol (1997), is a treaty signed by group of countries to reduce the emission of Carbon dioxide and

> Montreal Protocol is a treaty signed by group of countries to limit the production and use of CFCs.

6) Read the news article below and answer the following questions.

Arctic summer ice steadily shrinking

Arctic summer ice cover is constantly shrinking in the wake of climate change and global warming. By the end of August this year, Arctic summer sea ice covered only an area below 4-million sq. km. This means that the record set on Sept. 18, 2007 with a 4.17-million sq.-km has already been broken, and we are talking about the smallest minimum ice extent that was ever recorded in Arctic.


The scientists fear that this year's extreme melting of Arctic ice is only the beginning of the trend that will lead to Arctic being free of summer ice within the next 25-30 years, much sooner than it was previously thought.


The loss of Arctic summer ice will have serious consequences for our future well being. Arctic ice helps regulate the climate by reflecting the sunlight, and therefore cooling the climate. No ice would cause more moisture from the oceans to enter the atmosphere which would lead to more powerful and much more frequent storms. This increase in storm frequency and storm intensity will likely affect most of the world's populated places, leading to massive damages.


Arctic has already lost much of its thick (older) ice that would remain throughout the summer. Thirty years ago the ratio between thick, older ice and seasonal ice (ice that would melt away in the summer) was about 80 % older and 20% seasonal. Today, due to the rapidly growing global warming impact this ratio has almost reversed.


Also, there are huge quantities of organic carbon locked away as frozen plant matter in the big permafrost region of the Arctic, meaning that the further melting of Arctic ice could result in even more carbon emission being emitted in the atmosphere, leading to an even worse climate change impact.


Arctic is first in line when it comes to climate change impact. We sadly keep forgetting that climate change impact won't stop at Arctic but will spread further to an entire planet because we are talking about global phenomenon that will only increase in power and magnitude.Questions
a) According to the article above, What is meant by the 1st line, 'Arctic summer ice cover is constantly shrinking in the wake of climate change and global warming'.
b) Explain what is causing the constant shrinking of the ice. (1m)
c) Explain how your answer for (b) causes the constant shrinking of the ice. (6m)
d) Identify and describe any one impact caused by the constant shrinking of the ice stated in the article. (3m)
e) What measures can be taken to reduce Global warming? (6m)
(Reply with your email address and name for the answers)

6) What is Ozone Layer and Why is it important?

It is he layer of the Earth's atmosphere that surrounds us. It contains ozone molecules and extends about 15-50 kilometers above the Earth's surface. 

It is important because the Ozone layer acts as a shield / protective layer around the Earth, protecting life on Earth from the harmful Ultraviolet (UV) rays from the Sun.   UV rays can affect humans, plants and animals. Overexposure to UV rays can lead to skin cancer, cataracts, and weakened immune systems to Humans. It can also lead to reduced crop yield and disruptions in the marine food chain. 

7) In which part of the world is the extent of Ozone Depletion the greatest? Explain why is it so.

Ozone Depletion is the greatest over regions located at higher altitudes such as the Poles. 

This is because Click here for Ans.