Unit C Section 2.3 Flashcards
Why is carbon dioxide not a considered a pollutant?
since it is naturally present in the air
Why is Earth considered to be a natural greenhouse?
- Some gases in the atmosphere act like glass in a greenhouse.
- They trap heat from the Sun’s radiant energy.
- This heat keeps Earth at temperatures that allow living things to live, grow, and reproduce
What are the atmospheric gases that trap
heat called?
greenhouse gases
What are greenhouse gases?
- Water vapor,
- carbon dioxide,
- methane,
- nitrogen oxides
The Greenhouse
Effect:
- When radiant energy from the Sun reaches Earth’s
surface, much of it is reflected back into space
-But some of this energy is trapped near Earth’s surface by a layer of gases that act like the glass in a
greenhouse.
What is the enhanced greenhouse effect?
- The enhanced greenhouse effect results from the greater concentration of gases trapping even more heat.
- this increases overall temperatures on Earth
What contributes to enhancing the greenhouse effect?
-human activities such as burning fossil fuels and clearing land
What is global warming:
This temperature increase worldwide
What can global warming lead to?
Global warming may lead to climate change
What can occur due to climate change?
MORE…..
- violent storms,
- flooding of coastal areas from melting icecaps,
- greater ranges in the spread of diseases.
Which gases contribute most to enhance the greenhouse effect?
-After water vapor, carbon dioxide is the gas that contributes most to the enhanced greenhouse effect.
What causes global warming:
- caused at least partly by human activities.
- Natural events such as volcanic eruptions and forest fires may also be part of the cause of global warming
The Enhanced
Greenhouse Effect Phases:
- Human activities are generating more greenhouse gases, so many scientists have concluded that more heat is being trapped.
- This means that Earth’s surface temperature will continue to rise.
- This worldwide increase is called global warming.
How is the ozone layer in the atmosphere good for us?
- absorbs ultraviolet radiation (UV) from the Sun.
- By absorbing this radiation, the ozone layer protects organisms on Earth from damaging UV rays.
How far is the ozone layer away from the Earth’s surface?
-The ozone layer is a natural formation of ozone 15 to 50 km above Earth’s surface
What have scientists noticed about the ozone layer?
-they have noticed that this layer has become thinner, allowing more UV radiation to reach Earth’s surface.
What are “holes” in the ozone layer?
Very thin parts of the layer that are considered holes
Thinning ozone layer means
More harmful UV (ultraviolet) radiation on Earth.
What are the harmful effects of UV radiation:
- Increase of human skin cancer
- Increase of cataracts
- cause plankton to die (disrupt the food chain)
How is carbon dioxide being reduced in the atmosphere?
carbon dioxide is being captured and injected
into depleted oil reservoirs for enhanced oil recovery
What is causing thinning of the ozone layer:
- is caused by our use of chemicals called chlorofluorocarbons (CFCs)
What are CFCs used on?
- refrigerators,
- aerosol
- cans for products such as hair spray, and fire extinguishers.
What is the process for the thinning of the Ozone layer?
- CFCs travel from the lower atmosphere to the upper atmosphere.
- UV radiation breaks them down into substances, such as chlorine, that destroy ozone.
- Chlorine atoms react with the ozone molecules to form oxygen molecules (O2(g)
- One chlorine atom can remove 100 000 ozone molecules.
What happens to the ozone layer in the South pole?
- cold temperatures cause ice particles to form in the upper atmosphere.
- These ice particles speed up the reaction that removes the ozone molecules
