For several years believers and skeptics have argued about the causes of global warming. The problem is complicated because believers warn that man-made causes if left to advance too far may be irreversible. Reduction of the rainforests, continued growth in hydrocarbon industries, increases in livestock, and depletion of the ozone are all considered factors in the debate. Skeptics maintain that the climate change is a natural phenomenon, that man's effect on nature is largely overrated. The fact is that for several years, the earth's temperature is rising. The problem remains in deciding what if anything we can do about it. Your job is to use the Internet resources below to find scientific evidence to support the cause and effects of global warming. 

Part A: The Greenhouse Effect - Global Warming

View this short video clip about "The Greenhouse Effect (Global Warming)" and answer the following questions.

1. According to weather records from the last century, what has happened to the average surface temperature on Earth?

2. What do scientists believe is the cause of the climate change?

3. What did American geochemist David Kealing discover about CO₂ in the atmosphere?

4. How has the percentage of CO₂ in the atmosphere changed since the Industrial Revolution?

5. What evidence does the South Cascade Glacier in Washington State have to support the theory of global warming?

6. How much CO₂ do humans pump into the atmosphere every year?

Part B: Website Resources

Browse the websites below and answer the following questions.

Are our industrial and agricultural practices changing Earth's climate? You'll examine humankind's impact on the global environment as well as Earth's past in an attempt to answer this important question.

Earth on Fire  (NASA Classroom of the Future™)

http://www.cotf.edu/ete/modules/carbon/earthfire.html