How much of the United States total energy use is solar energy?
1%
How much of the United States total energy use is hydroelectric power?
3%
What is one reason we cut down trees (deforestation)?
Urban development, expand farm land,
What is the human carrying capacity?
WE DON'T KNOW
What are the two types of coal mines?
Open pit/ strip and underground/shaft
What is an advantage of solar power?
It is always renewable, generates no pollution
What is one advantage and disadvantage to wind energy?
Disadvantages: need batteries to store the energy, wind turbines can be noisy and change appearance of landscapes, can disrupt migration of patterns of some birds, are not very efficient
What are two downsides to Deforestation?
Many plants and animals lose their habitat. Less plants to remove carbon dioxide from the atmosphere.
What can you do reduce pollution?
What is one example of a bad oil spill.
Deepwater Horizon oil drilling plant leak in 2010
Exxon Valdez tanker leak in 1989
What are two disadvantages of solar power?
Not very efficient, costly to set up, not always reliable since you may not have consistent sunlight.
What is one advantage of hydroelectric power?
Produces almost no pollution, are the most cost-efficient energy source, and lakes created by damming can provide water for drinking, crop irrigation, or recreation.
What effect did farming have on Honey Bees?
Insecticides used by farmers killed almost 1/3 of honeybees over a 30 year time.
What are two ways air can become polluted?
Photochemical smog, Chlorofluorocarbons (CFCs), Acid precipitation.
Draw or explain the greenhouse effect in detail.
The sun is constantly blasting earth with heat energy, some of that energy is taken in and absorbed by the earth, that energy bounces around in the atmosphere a few times finally it leaves Earth and goes off into space.
Greenhouse gasses cause that heat to bounce extra times and in turn heat up the earth.
How do hydroelectric power plants generate electricity?
Because of gravity, water flows downstream which then crashes into and spins a turbine which generates electricity.
What is one disadvantage to hydroelectric power?
Can disrupt natural ecosystems, can disrupt fish migration patterns, and hydroelectric power sources are limited to bodies of water (lakes, rivers, and unused coast lines)
What effect did farming have on Bald Eagles?
The pesticide DDT, used by farmers, caused a reaction in the food chain that eventually led to Bald Eagles having soft eggs. The soft eggs either caused birth defects or didn't hatch leading to a severe drop in Bald Eagle numbers
What are two ways water can become polluted?
Why did the human population begin to start growing rapidly around 1900?
Because of the Fritz Haber Process, increasing availability of clean water, better food, increased birth rate.
How do photovoltaic cells work?
One side of the photovoltaic cell is rich in electrons, the other side not. When solar energy hits the electron rich side, it causes the electrons to flow, creating electricity.
How do Geothermal power plants work?
Water is pumped into the ground where it comes into contact with very hot rock and changes into steam. Steam returns to the surface and spins a turbine to generate electricity.
What is the main concern with clearing forests to create farmlands?
These farms are highly susceptible to severe erosion from heavy rains and floods.
What are the three steps water treatment plants go through to clean our water?
Separate solid materials from the sewage
Kill harmful microorganisms
Reduce amount of nitrogen and phosphorus in the water.
There are two estimates for the human carrying capacity. Fully explain one.
2 billion: There was around 2 billion people in 1900. This estimate is based on the fact humans were doing very little environmental damage prior to 1900.
12 Billion: This number is based on the human population estimate when we start running out of all fossil fuels around 2100.