Using Satellite Imagery to Discuss the Science Behind Brazilian Deforestation
Students can delve into earth science by using satellite imagery to learn about the deforestation of the Brazilian rainforest.
By Bruce Howard
For several decades people concerned about the environment have had their eye on Brazil where vast areas of land are being deforested each year. Brazil loses more than 15,000 square kilometers to deforestation each year -- an area about the size of New Jersey, Northern Ireland, or twice the size of Puerto Rico. Brazil is home to more than a quarter of Earth's tropical forests.
But deforestation is about much more than saving trees. It is a complex topic worthy of study, with layer upon layer of interesting subtopics which can make studying earth science utterly fascinating. Here's how I suggest laying out a study of the topic. You will need access to computers, because this approach makes use of rich satellite imagery, making the topic visual and concrete for middle school or younger high school aged learners.
How to Get Started With Deforestation Lessons
Begin with an examination of the issue itself, being careful to shy away from the propaganda, and stick with topics rich with scientific implications. This Global Climate Change lesson has a nice introduction to the topic and makes use of satellite imagery as visualized using Google Earth. Two sites students could use for research include NASA's World of Change (also has a downloadable Google Earth file), and Monga Bay.
Use the Information to Promote Further Study
Using what you just covered, have your class come up with a list of questions and topics for further study. For example, we know that impoverished ranchers are burning acre upon acre of forest to create pastures for cattle:
- One main effect is a loss of trees and the forest canopy. This means less greenery, and therefore less oxygen. On the flip side, more carbon dioxide remains. This is a good time to study photosynthesis.
- Not only do you have a decrease in carbon dioxide consumption, but you also have the effect of reintroducing all the carbon that was stored in the greenery back into the environment. This leads to an examination of the carbon cycle and an interesting study on the greenhouse effect and the Keeling curve.
- There is the sheer amount of smoke (also called aerosols) being released into the atmosphere. This can lead to a study on atmospheric aerosols, particulate matter, and global cooling.
Break your students into groups of four and assign each group one of these topics to study-- using satellite imagery. Satellite imagery is one of the main tools in the arsenal of today's earth scientists. For example, they may want to compare carbon dioxide levels in forested areas with deforested areas. Go into the computer lab and let each group of four work on two computers to research their topics. A fantastic website for exploring satellite imagery and earth science is My NASA Data (You may want to use this lesson on the carbon cycle, using Rondonia, Brazil in place of Lake Erie. Ask teams to present their findings using images they have downloaded, pointing out their observations to the class. What follows are more lessons about Brazilian Deforestation.
Brazilian Deforestation Lessons and Activities:
This lesson provides an overview of how deforestation in Brazil affects the earth's biosphere, atmosphere, geosphere and hydrosphere, and includes a discussion of the carbon cycle, the greenhouse effect, and the Keeling curve. There is also a Google Earth activity.
Students examine two data sets to find correlations, and explain the importance of carbon dioxide and photosynthetic plants in the carbon cycle.
This simple lesson provides a list of topics to use to introduce the issues associated with deforestation. It includes a quiz and answer key.
Students study biodiversity and develop a policy brief on the issue. This lesson was taken from a collection of lessons from the U.K. which feature creative projects about the Amazon rainforest including video production, posters, and role-playing.