Global warming is an average increase in the temperature of the atmosphere near the Earth's surface and in the troposphere, which can contribute to changes in global climate patterns.  This process may  last for an extended period (decades or longer). The "greenhouse effect" refers to the natural phenomenon that keeps the Earth in a temperature range that allows life to flourish. The sun's enormous energy warms the Earth's surface and its atmosphere. As this energy radiates back toward space as heat, a portion is absorbed by a delicate balance of heat-trapping gases in the atmosphere—among them carbon dioxide and methane—which creates an insulating layer. With the temperature control of the greenhouse effect, the Earth has an average surface temperature of 59°F (15°C). Without it, the average surface temperature would be 0°F (-18°C), a temperature so low that the Earth would be frozen and could not sustain life. Global warming" refers to the rise in the Earth's temperature resulting from an increase in heat-trapping gases in the atmosphere.

 

Figure 1.0 Green house gas emission.

 

Figure 1.0 describes the source of green house gases. Global warming is caused by green house gases, which trap in the sun’s infrared rays in the earth’s atmosphere. The trapped infra rays,  in turn heat up the earth’s atmosphere. Greenhouse gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), a number of fluorinated gases, and water vapor (H2O).

What is causing global warming?

 Scientists have concluded that human activities are contributing to global warming by adding large amounts of heat-trapping gases to the atmosphere. Every time we drive a car, use electricity from coal-fired power plants, or heat our homes with oil or natural gas, we release carbon dioxide and other heat-trapping gases into the air. The second most important source of greenhouse gases is deforestation, mainly in the tropics, and other land-use changes.

As the concentration of these gases grows, more heat is trapped by the atmosphere and less escapes back into space. This increase in trapped heat changes the climate, causing altered weather patterns that can bring unusually intense precipitation or dry spells and more severe storms. Refer to Figure 3.0 .   

 

Figure 2.0 Effect of greenhouse gas. Picture Source USC

 

Is global warming already happening?

In 1988, the United Nations Environment Programme and the World Meteorological Organization set up the Intergovernmental Panel on Climate Change (IPCC) to examine the most current scientific information on global warming and climate change. IPCC reported examples of observed climatic changes;

• Increase in global average surface temperature of about 1°F in the 20^th century
• Decrease of snow cover and sea ice extent and the retreat of mountain glaciers in the latter half of the 20^th century
• Rise in global average sea level and the increase in ocean water temperatures
• Likely increase in average precipitation over the middle and high latitudes of the Northern Hemisphere, and over tropical land areas
• Increase in the frequency of extreme precipitation events in some regions of the world

The rise in mean temperature of the earth’s surface temperature, is shown in Figure 3.0 data for the past 140 years.

 

Figure 3.0 data for the past 140 years. Picture Courtesy.Tanggang Public Lecture UKM

 

How Malaysia can be affected by global warming ?

In Malaysia , the effects can be :

·         Gradual Increase in temperature-  heat wave , haze episode

·         Extreme weather conditions – floods, storms, extreme rainfall (Figure 4.0), typhoon (Figure 7.0)

·         Shift in climatic patterns -  drought,  widespread flooding (Figure 5.0, 6.0), forest fire.

·         Rise in sea level –  high tide, (Figure 8.0)

 

 

Figure 4.0 Extreme rainfall patterns. Picture  Courtesy.Tanggang Public Lecture UKM

 

Figure 5.0 Extreme weather and flood occurrence in Johor, Kedah and other states. Courtesy.Tanggang Public Lecture UKM

 

Figure 6.0 Extreme weather patterns  Picture courtesy Tanggang UKM public lecture

 

 

Figure 7.0 Typhoon may bring in flood – thus the need for warning system. Picture courtesy Tanggang UKM public lecture

 

 

Figure 8.0 High tide

 

Conclusion- What can we do ?

The  impacts of global warming on us may be felt gradually. The impacts shall be felt in many  aspects such as health, forests, crops yield, water supply, erosion of beaches, loss of habitats and species.

There are many ways we can do to reduce global warming. Governments can adopt a range of options for reducing greenhouse gas emissions, including

• increasing energy efficiency standards
• encouraging the use of renewable energy sources (such as wind and solar power)
• protecting and restoring forests, which serve as important storehouses of carbon
• disaster mitigation – flood warning and prevention

Individuals can reduce the need for fossil fuels and often save money by

• driving less and driving more fuel-efficient and less-polluting cars
• using energy-efficient appliances
• using less electricity in general