Name: #: Date: 5.8 The Greenhouse Effect The greenhouse effect traps heat in the atmosphere. This helps the Earth remain warm enough for humans. Without the greenhouse effect, human would not be able to survive on Earth. Unfortunately, human activity has forced the system out of balance. This has led to climate change. How the Greenhouse Effect Works A diagram of the greenhouse effect. The Earth receives radiation from the sun. This radiation includes the visible light that can be seen with the human eye. Is also includes the ultra violet light and infrared light that cannot be seen. Some of the sun s radiation hits Earth and bounces off of surfaces like snow, sand, and clouds and heads back out into space. The rest of the radiation remains in the Earth s atmosphere. It is absorbed by oceans, land, and the air itself. As Earth s surfaces and oceans heat up, the release some of the infrared radiation back into the atmosphere. Some of this infrared radiation is captured in the atmosphere by greenhouse gases. Some greenhouse gases include water vapor, carbon dioxide, methane, and nitrous oxide. The more heat the greenhouse gases capture, the warmer the Earth becomes. The greenhouse effect works just like a greenhouse that grows plants. This is where its name comes from. Sun enters a greenhouse and is absorbed by the plants. The infrared radiation inside is too weak to pass back through the glass to escape. It ends up keeping the greenhouse warmer than the outside air. This helps plants grow no matter the climate. The same concept occurs in a car during the winter. This is why the inside of a car can be warm even on days with chilly weather. 1
The Greenhouse Effect works just like a greenhouse. The Role of Humans in the Greenhouse Effect Without the greenhouse effect, the Earth would be similar to other planets that are either far too hot or cold for human life. The moon, for example, drops below -240 degrees Fahrenheit. Meanwhile, the average temperature on Venus in 864 degrees Fahrenheit. The greenhouse effect keeps Earth at a steady temperature. However, too much of a good thing can become a bad thing. Most scientists now agree that the greenhouse effect has been thrown out of balance due to human activity. The greenhouse effect is now a major threat to the global climate. Scientists use computers that can measure and predict greenhouse gas levels over time with simulations like this one. 2
This dangerous human activity began during the Industrial Revolution in the 1800s. During this time, humans began burning oil, gasoline, and coal to power factories, trains, and other new technology. At the same time, the demand for wood and clear land grew. This led to deforestation. Now, 200 years later, the levels of carbon dioxide in the air have grown to new levels. More and more carbon dioxide is being released into the air. At the same time, humans are cutting down the trees and killing the marine life that are able to convert carbon dioxide into oxygen. Burning fossil fuels releases greenhouse gases into the environment. With so many greenhouse gases, more of the sun s radiation is becoming trapped in Earth s atmosphere. Many scientists believe that this has caused the Earth to become warmer. This leads to warmer seas, changing tides and currents, flooding and drought, devastating storms, and more. These frightening consequences are known as global warming or climate change. This has raised interest in renewable energy and more efficient ways to minimize the levels of greenhouse gases in the atmosphere. Ten signs that the world may be warming up due to the greenhouse effect. 3
Writing Describe the connection between humans, the greenhouse effect, and global warming. Reading 1) Which quote from the text explains how the greenhouse effect works? o "Some of the sun s radiation hits Earth and bounces off of surfaces like snow, sand, o "The more heat the greenhouse gases capture, the warmer the Earth becomes." o "Some of this infrared radiation is captured in the atmosphere by greenhouse gases." o "This is why the inside of a car can be warm even on days with chilly weather." 2) Which quote from the text shows the importance of the greenhouse effect? o Some of the sun s radiation hits Earth and bounces off of surfaces like snow, sand, o Without the greenhouse effect, the Earth would be similar to other planets that are either far too hot or cold for human life." o This leads to warmer seas, changing tides and currents, flooding and drought, devastating storms, and more." o "The moon, for example, drops below -240 degrees Fahrenheit. Meanwhile, the average temperature on Venus is 864 degrees Fahrenheit." 4
3) Which quote from the text shows the problems caused by the greenhouse effect? o Some of the sun s radiation hits Earth and bounces off of surfaces like snow, sand, o Without the greenhouse effect, the Earth would be similar to other planets that are either far too hot or cold for human life." o This leads to warmer seas, changing tides and currents, flooding and drought, devastating storms, and more." o The moon, for example, drops below -240 degrees Fahrenheit. Meanwhile, the average temperature on Venus is 864 degrees Fahrenheit." 4) What is radiation? o part of a greenhouse o global warming o dangerous weather o light from the sun 5) What are "greenhouse gases"? o gases that trap heat o gases that cause rain o gases that help plants grow o gases that cool the Earth 6) What does it mean for the oceans to "absorb" greenhouse gases? o send out o take in o release o create STUDENT REFLECTION What I did well: Future Steps: 5