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| Gamma rays, X-rays, and ultraviolet light have _____ wavelengths of energy than visible light and ____ energies. | shorter, higher,  |
| Radiowaves, microwaves, and infrared have _____ wavelengths of energy than visible light and ____ energies. | longer, lower |
| Energy that strikes an object and bounces back is said to be ______. | reflected |
| Energy that strikes an object and passes right through the object (like visible light going through glass) is said to be ______. | transmitted |
| Energy that strikes an object and causes the object to gain energy (by causing its electrons to move further from the nucleus) is said to be ______. | absorbed |
| The higher energy wavelengths of energy that reach the earth are absorbed by the ground (and water), causing the Earth to heat up. The Earth tries to cool down by radiating energy back into space, usually in the form of longer wavelength ________ rays that can be blocked from escaping by greenhouse gases. | infrared,  |
| The Earth must ____ or reflect about the same amount of energy coming in from the sun back out into space, or else the Earth will gain more and more energy, causing it to heat up. | radiate, |
| Greenhouse gases are gases that transmit energy coming from the ____ but absorb energy coming from the ____. | sun, ground |
| TRUE or FALSE: The greenhouse effect is what keeps our planet warm enough for life to exist. | TRUE |
| _________ refers to the increase in average temperature of the Earth's biosphere. | Global warming |
| The extra energy in the atmosphere due to the warming of Earth's climate may be leading to stronger ______. | storms |
| Besides temperature and greenhouse gas concentrations, what else has been rising due to global warming? | sea levels (due to melting ice caps and glaciers) |
| The extremely high rate of ______ of many species around the world may in part be due to global climate change. | extinction |
| Which gas gets the majority of the blame for global warming? | carbon dioxide (Even though water vapor is in higher concentrations on average than CO2, and produces most of the greenhouse effect humans have not been directly adding any additional water vapor to the air. Methane is a stronger greenhouse gas than carbon dioxide, but is in a much lower concentration in the air than CO2) |
| Which gas is the second leading culprit for causing global warming, and is an even stronger greenhouse gas than the one that gets most of the blame for global warming? | Methane (Methane is even more efficient at trapping heat than CO2, but there's much less of it, so it doesn't get as much of the blame) |
| There is a lot of methane trapped in arctic permafrost. As global temperatures rise, more and more permafrost melts, releasing this greenhouse gas into the atmosphere. The system just described is an example of a _____ feedback system. | methane, positive (It's an example of a positive feedback because it accelerates global warming. The warming causes permafrost to melt, releasing more methane, which traps more heat, which causes more permafrost melting, which releases more methane, which traps more heat, etc....) |
| Global climate change may be causing some areas of the world to be getting too dry to grow crops. This is a phenomenon known as _____. | desertification (which literally means, "the process of becoming desert-like") |
| Which animal receives a lot of blame for increases in atmospheric methane levels? | Cows (They release a lot of methane when they release gas from their posterior area, just below their tails. This release of gas is politely known as flatulence.) |
| The main cause of the increasing levels of carbon dioxide in the atmosphere is the ______. | burning of fossil fuels |
| A growing tree can help lower the amount of _______ in the atmosphere because it is a gas that is required (along with water), for photosynthesis to occur. Photosynthesis converts the carbon atoms in this gas into the organic molecules that make up the growing tree. | carbon dioxide |
| Which human activity is the second leading cause of the increase in carbon dioxide levels in the atmosphere? | Deforestation (Cutting down forests prevents trees from doing photosynthesis, leading to less CO2 being taken out of the atmosphere. Often times, the forests are burned to clear them quickly so the land can be farmed. Burning the trees releases the carbon stored in the trees directly back into the atmosphere as CO2) |
| If global warming caused the average amount of cloud cover on this planet to increase, that would be an example of a _____ feedback because clouds are good at reflecting energy from the sun back out into space, and would help slow down global warming. | negative (A negative feedback happens when anything that is caused by the increase in something works to slow down the increase in that original cause) |
| ____ feedbacks cause a trend to slow down or reverse themselves. | Negative |
| ____ feedbacks cause a trend to speed up. | Positive (An example of a positive feedback with global warming is melting of snow and ice. Global warming causes there to be less snow and ice covering the planet. With less snow and ice to reflect the suns energy back out into space, the earth warms up more and causes even more snow and ice to melt. Both trends are sped up) |
| ____ feedbacks work to achieve homeostasis in a system. | Negative (because they help to bring a system back to a normal level. For example, sweating is an example of a negative feedback because it is caused by being overheated, but then it helps the body cool down and get back to its normal temperature) |
| The amount of carbon dioxide that you are responsible for putting into the air by directly burning fossil fuels for things like heating and transportation is known as your ______ carbon footprint | primary carbon footprint |
| The amount of carbon dioxide that you are responsible for putting into the air by buying products (that require CO2 emitting energy in order to be built in factories) is known as your ______ carbon footprint. | secondary carbon footprint |
| Which type of fossil fuel is used to generate most of the electricity in the United States? | Natural gas |
| Which type of fossil fuel is used to generate most of the electricity in the World? | Coal |
| Which type of fossil fuel provides for most of the World's energy needs? | Oil |
| A controversial method of drilling for natural gas that involves injecting toxic chemicals thousands of feet underground at high pressures to break up shale rock and release methane gas. | fracking |
| Which country would the Keystone XL pipeline have connected to oil refineries in the United States? | Canada |
| Which fossil fuel is the least polluting in terms of the amount of CO2 produced when it is burned to supply a certain amount of energy? | Natural Gas |
| TRUE or FALSE: Natural gas does not produce greenhouse gases when it is burned. | False |
| When the price of something, like gasoline, goes down, people use ____ of it. | more |
| TRUE or FALSE: Nuclear power creates air pollution. | FALSE (The only thing that is released into the air from a nuclear power plant, unless there is an accident, is water vapor) |
| TRUE or FALSE: Burning biomass and biofuels for energy does not ADD any new greenhouse gases to the atmosphere. | TRUE: Although burning any type biomass, like wood, ethanol, or biodiesal, releases carbon dioxide into the atmosphere, that is CO2 that was already in the carbon cycle. As you grow more plants to convert into biofuels, they will absorb CO2 back out of the atmosphere for photosynthesis. If the plants didn't get used for biofuels, they would eventually die and decompose, or be eaten, and would be converted into CO2 anyway. The only thing that really adds new CO2 to the atmosphere is digging or drilling up fossil fuels from deep underground and burning them) |
| Nuclear reactions that involve the splitting of the nucleus of a larger radioactive element's nucleus into smaller nuclei, creating new and smaller elements, are called ____ reactions. | fission |
| Nuclear reactions that involve smashing 2 smaller atoms together to create a new element with a bigger nucleus are called _____ reactions. | fusion |
| TRUE or FALSE: The type of reactions that heat water and boil it to produce the water vapor that turns a turbine in a nuclear power plant are fusion reactions. | FALSE (That would be nice, but we haven't figured out how to use fusion yet to generate cheap energy. It would be nice because fusion reactions don't produce radioactive waste like fission reactions do)) |
| Every radioactive element has its own unique ______ which is a measurement of the amount of time it takes for half of the atoms in a sample of that element to break into smaller atoms, and in the process become a new element. | half-life |
| If you have a sample of a radioactive element that has a half-life of 1 million years, ____ % of the sample will still be here 1 million years from now, and the percentage that will remain 2 million years from now will be ____%. | 50%, 25% |
| Energy sources that can be used without causing the supply to decrease over time are called _____ energy sources. | renewable |
| Examples of using _____ for fuel include using wood, ethanol, biodiesel. | biomass |
| The blades of a windmill are really just a giant ____. | turbine |
| Noise and killing wildlife are disadvantages of using ____ energy. | wind |
| Oil extracted from plants can be used as _____ fuel. | biodiesel |
| Fermenting the sugars in plants to produce alcohol and then distilling it to make it strong so it can be used as a fuel is the basic process for producing ______. | ethanol |
| Which type of fuel can be extracted from the waste from cows or landfills that is allowed to decompose under anaerobic conditions? | methane |
| ____ can be used to generate electricity by allowing water in the liquid state to flow through them, turning a turbine that is attached to a generator. | Dams |
| Geothermal heating and cooling can be used _____ while geothermal power plants are located _____ | anywhere, in volcanically active areas |
| Which country gets most of its energy from geothermal sources? | Iceland |
| Passive solar involves designing _____ to more efficiently use the energy from the sun. | buildings |
| Solar panels use materials, like _____ that can generate an electrical current when their electrons are excited by solar energy of different wavelengths. | silicon |
| The biggest benefit of using hydrogen as a fuel is that the only direct waste product from its use is ____. | water |
| TRUE or FALSE: You can obtain hydrogen from natural gas (methane) without generating any greenhouse gases. | FALSE (The chemical reactions that extract hydrogen gas from a certain amount of methane ultimately produce just as much CO2 as would be generated by burning the same amount methane for energy directly. In addition, drilling for methane in order to use it to get hydrogen lets some methane escape into the atmosphere. However, hydrogen can be used in fuel cell engines more efficiently than methane can be burned in internal combustion engines, so using hydrogen made from methane can lower your carbon footprint compared to using natural gas/methane) |
| Using the process of electrolysis to generate hydrogen still produces carbon dioxide pollution if you use ____ to generate the electricity needed for electrolysis. | fossil fuels |
| The process of electrolysis can be used to split ____ to produce hydrogen gas. | water |
| Hydrogen gas must be put under a lot of pressure or cooled down to extremely low temperatures in order to turn it into ____ hydrogen so that it takes up less space and can be transported efficiently. | liquid |
