Deforestation/Global Warming

From WikiEducator
Jump to: navigation, search

Icon objectives.jpg
Module Five Objectives

After completion of this Module, you should be able to:

  • Understand what global warming is.
  • Understand that carbon exists in a variety of forms on earth.
  • Understand the greenhouse effect.
  • Explain the link between deforestation and global warming.
  • Compare and contrast hybrid and fuel cell cars.
  • Explain the carbon cycle.

Introductory Activity

Icon reflection.gif



Reflect on (think about) the photo below and, in a group, discuss what you see in the picture. Can you answer all the "I wonder..." questions below?

Orang-utan bukit lawang 2006.jpg


  • I wonder what this animal is?
  • I wonder what the animal is thinking?
  • I wonder how a temperature increase in this animal's habitat would affect it?

Global warming

Climate change is happening faster than we actually think. Carrying on living the way we do and not thinking about what we can do to slow down climate change - and then doing it - can be dangerous. The earth could be getting warmer on its own, but many of the world's leading climate scientists think that the things people do are helping to make the earth warmer. Global warming refers to an increase in the earth's average near-surface and ocean temperatures. Global warming “facts” are hard to come by. One of the few facts that most scientists agree upon is that the current average temperature of Earth has risen over the past 100 years. According to most estimates, this increase in temperature amounts to about 0.4-0.8 °C (0.72-1.44 °F) over this period of time.

A warmer earth may lead to changes in rainfall patterns, a rise in sea level, and have a wide range of impacts on plants, wildlife, and humans. When scientists talk about the issue of climate change, their concern is about global warming caused by human activities. Of most significance to low lying areas (those that are very close to, or below sea level) is that global warming has an effect on ice - glaciers or icebergs melt, raising the level of the sea water. This rising sea level then affects the land as the sea floods these areas. Even if the sea water could be stopped from flooding an area, the land is made infertile by the salt: it cannot grow crops. Land in many arctic regions of the world is lost because of this.

People design homes for cold weather in Europe because most parts of Europe are very cold. With the change in global weather, these homes are now unsuitable because the weather is warmer and the houses are too warm.

Habitats and ecosystems

The animal and plant life living together in an area is called an ecosystem – all living things are included in and rely on these ecosystems. Many ecosystems depend on a delicate balance of rainfall, temperature and soil type. A rapid change in climate could upset this balance and seriously endanger many living things, crops and even human health.

Icon activity.jpg
Activity One: Global Warming

Read the articles provided by your teacher and then answer the questions below on your own:

  1. What is global warming?
  2. List four causes of global warming.
  3. List four effects of global warming.

Your teacher will now divide the class into groups. In your groups, discuss and compare answers, ensuring that you are able to:

  1. Explain the link between deforestation and global warming.
  2. Decide whether there is a strong case for saying that deforestation contributes significantly to global warming.
  3. Create a presentation to persuade the other groups that there is, or is not a case to be answered: this presentation could be a PowerPoint slideshow, speech, mini play/skit, report, or poster.

Hybrid and Fuel Cell Cars

In an attempt to combat pollution and the release of carbon dioxide, car companies have, for years, been researching and testing alternative fuels for cars. They have specifically been looking at fuels that do not emit carbon dioxide when burned and those that emit lower levels of Carbon. There has also been a lot of research and development of electric and solar power cars, and hybrid cars. Out of these variants, there have been some successes with Hydrogen-based fuels, but the most successful type of car has been the hybrid. A hybrid car has a small petrol or diesel engine, and an electric motor which usually drives the wheels. The petrol or diesel engine is used to charge the batteries and provide more power to the wheels when required, and the cars usually use regenerative braking. Regenerative braking means that the electric motor in the car is used to slow the car down, but in the process generates electricity which then charges the batteries.

What are the Advantages of Hybrid Cars?

Most car companies manufacture hybrid cars. Some examples are Honda, Toyota, Nissan, Mazda, Ford, Chrysler, Lexus, etc. Hybrid cars are "cleaner" that traditional cars. They have much lower emissions, resulting in less pollution due to exhaust gas.

These hybrid cars can be as much as three times as efficient as normal petrol driven cars. Therefore, the primary advantages of electric cars over petrol cars are their lower emissions of carbon dioxide (CO2), and higher efficiency. Hybrid cars have a tendency to recapture significant amounts of energy during braking that is normally wasted as heat.

Finally, these cars are practical in that they can be fuelled using petrol or diesel that is purchased from the local gas/petrol station.

What are the Disadvantages of Hybrid Cars?

The expense is the primary disadvantage of hybrid cars. They are not only more expensive than their petrol equivalents, but they are also less powerful, so they do not perform as well and would not be suitable for towing a boat or trailer. They are also more complex and expensive to service and maintain, and require mechanics with specialist knowledge, to service them.

Icon activity.jpg
Activity Two: Hybrid and Fuel Cell Cars

Your teacher will divide you into pairs and provide you with information about either fuel cell cars or hybrid cars. When instructed by your teacher, do the following:

  • Read the article that you have been given. List the advantages and disadvantages of each type of car.
  • Once you have completed your list, join up with another pair who do not have the same type of car as you do - your teacher may assist with this. Exchange information with the new pair.

In your new group of four:

  • Create a Venn diagram with hybrid car characteristics in one circle and fuel cell car characteristics in the other circle. What do these two types of cars have in common? Write the common characteristics in the overlap between the circles. (Ask your teacher if you have forgotten what a Venn diagram is.)
  • Take a group vote to decide which car you will work with in the next task.
  • Draw up a list of positive characteristics for this car.
  • Design an advertisement for your chosen car that highlights the positive characteristics that your group has identified.

Carbon Cycle

Icon activity.jpg
Activity Three: Carbon Cycle

Your teacher will divide you into groups and give each group member a copy of an article that includes a diagram. Once each group member has finished reading the article:

  • Decide on a set of seven good questions relating to the article and diagram. At least one of these questions must be about the diagram.
  • When all groups have finished creating their questions the teacher will collect the list of questions, and provide each group with the questions created by another group. In your group, discuss the answers to all the questions that you have been given, and write down the best answers you can.
  • Once everybody has finished, discuss or construct a Plus-Minus-Interesting (PMI) chart (example below) to help decide:
    • How effective the questions that you answered were.
    • How interesting the questions were.
    • How good the questions were.
  • When constructing this chart, make sure you are positive, encouraging and give good feedback.
  • Once you have finished, choose the best questions and answers from those that you worked on, and highlight them.
  • Your teacher will let each group come up and write their chosen best questions on a large poster which will have the article and diagram on it. Once this has been completed, your teacher may put this up in the library so that others can learn about the carbon cycle.

Plus Minus Interesting
Anything positive in this column. Anything interesting in this column. New ideas and interesting comments in this column.

Icon activity.jpg
Activity Four: Word Bank

Add new vocabulary to your Word Bank and make sure that you have spelt them correctly. These words and their definitions will help you write a report at the end of the unit.

Ongoing Assessment

Icon qmark.gif


Assessment One: KWL Chart

It's KWL time! Return to the KWL chart. As you have now reached the end of Module Five, read through all your additions to your KWL chart - can you add anything more?

Have you gained any knowledge that helps you answer your big question? Fill in any answers on your KWL chart and add any new information or new questions that have come up, in order to see if deforestation is good or bad for a community.

Teacher Notes