Chapter
6
Climate Change
By Susan Stempleski
This chapter outlines a 50-minute lesson that focuses on the theme of climate change. The lesson begins with a warm-up activity in which students review the key term "climate change" and participate in a brief class survey to stimulate their interest in the topic of global warming. Students then read and discuss a short article on climate change. Next, they carry out a ranking task that encourages them to reflect more deeply on the effects of global warming. Finally, students write a brief paragraph summarizing what they have learned in the lesson and share their summaries with the class.
As students read, write, and talk about climate change, they improve their language skills by learning and using new vocabulary and concepts related to the topic. Some teachers may choose to present the activities described in the section on Classroom Applications as a single 50-minute lesson. Others may prefer to combine the activities with some of the materials outlined in the section on Internet Resources to create a longer lesson or a more extensive unit of several related lessons. The issue of climate change, especially as it relates to global warming, is complex and controversial. There are many questions about the topic, from its causes to its full effects, which cannot be fully covered in a 50-minute lesson. Teachers who want their students to explore the topic more deeply can use the sequence of activities described here as an introductory lesson.
The Intergovernmental Panel on Climate Change (IPCC), a United Nations group that was created to give scientific advice on climate change, published its Second Assessment Report in December 1995. According to the IPCC report, there is a great deal of evidence indicating that certain human activities are causing the warming of the Earth’s atmosphere. The report says that unless steps are taken to prevent further global warming, the average surface temperature on Earth will rise by about 1 to 3 degrees Centigrade by the year 2100. This predicted change is larger than any climate change the Earth has experienced in the past 10,000 years.
There is some uncertainty about the effects of climate change, but many experts believe that global warming would cause the following:
Health -- Tropical diseases such as yellow fever and malaria would spread to a wider area.
Wildlife -- Many animal and plant species would become extinct because warmer temperatures would cause their habitats to change or disappear.
Oceans -- Sea levels would rise and cause flooding in coastal areas and very serious damage in low-lying countries such as Bangladesh.
Agriculture -- Growing seasons in Canada, Finland, Japan and other countries in the Northern Hemisphere would become longer. However, sizes of wheat, corn and other soybean crops would become smaller, causing food shortages in some areas of the world.
Forests -- Parasites from tropical areas would extend their range and attack forests in temperate zones. Some tree species in temperate zones would become extinct.
Rangelands -- Drought and erosion would become worse, and increase fires would become a problem.
Islands -- If the oceans rise, some small islands, including the Caribbean Islands and archipelagos in the Pacific, might disappear.
The main cause of the recent increases in global temperature is greenhouse gases, especially carbon dioxide, released by coal- and oil-fired power stations, factories, automobiles, trucks, offices, and private homes. As world population and economies grow, more and more greenhouse gases are released. As more and more of these gases enter the atmosphere, they trap the Earth’s heat and add to global warming.
Until recently, some people argued that no action should be taken against global warming until we know exactly what effects it will have on the environment. However, scientists have shown that major changes in the atmosphere have already taken place, and that these changes will damage the environment. Furthermore, we do not know if these changes are permanent or only temporary. One fact is certain: the longer we delay action against global warming, the more difficult it will become to take effective steps.
In order to prevent further global warming, we would have to immediately reduce carbon dioxide emissions by 50-70%. Experts say it would be impossible to do this. However, it is possible to keep amounts of carbon dioxide below danger levels, even though we would still experience an increase in the Earth’s temperature. To do this, we have to reduce worldwide carbon dioxide emissions gradually until they are much lower than the current level.
To achieve the goal of keeping carbon dioxide levels below danger levels, the 180 countries that participated in the 1992 United Nations Conference on Environment and Development ("Earth Summit") were invited to sign the United Nations Framework Convention on Climate Change. The goal of the Convention is to eventually stabilize amounts of greenhouse gases at safe levels. The developed countries that are members of the Convention agreed to take steps to reduce their emissions to 1990 levels by the year 2000.
At the climate treaty negotiations held in Kyoto in December of 1997, the parties to the United Nations Framework on Climate Change reached agreement on a historic agreement, the "Kyoto Protocol," for reducing greenhouse gas emissions after the year 2000. The protocol calls for protecting the environment by improving the way energy is produced and consumed, among other measures. According to the agreement, developed countries are legally required to reduce their emissions of greenhouse gases by at least 5% compared to 1990 levels by the period 2008-2012.
