A large amount of the world's drinking water comes from desalination.​

We are using freshwater unsustainably through waste and pollution, and do not charge enough for its use.​

Withdrawing freshwater from deep aquifers amounts to mining a nonrenewable resource.​

Eutrophication is a condition of natural nutrient enrichment of a shallow lake, estuary, or slow-moving stream.​

A source of groundwater contamination in coastal areas is saltwater intrusion.​

The creation of dams and reservoirs has decreased the annual reliable runoff available for human use.

An oligotrophic lake tends to have relatively low levels of nutrients.​

Heat is a major water pollutant that makes some species vulnerable to disease.​

Preventing contamination is the least expensive and most effective way to protect groundwater resources.​

Water covers approximately ____% of Earth's surface.​

What is a water resource that can be considered nonrenewable?​

What is the portion of surface runoff that we can generally count on as a stable source of freshwater?​

What phenomenon can alter the hydrologic cycle on a global scale?​

Freshwater that is used indirectly is called ____, which is the freshwater that is not directly consumed but is used to produce food and other products.​

What is the primary problem with drawing groundwater from near ocean coastlines?

Large dams and reservoirs ____.​

What is formed when extreme sudden subsidence occurs within a depleted aquifer?​

What is a major disadvantage of desalination?​

What percentage of the water that people use throughout the world is lost through evaporation, leaks, and inefficient use?​

What is the most efficient form of irrigation?​

What has resulted along floodplains from channelization and loss of vegetation?​

What is an example of point source pollution?​

What is by far the leading cause of water pollution?​

What aquatic ecosystem is most capable of diluting, dispersing, and degrading large amounts of sewage, sludge, and oil?​

The initial amount of low-quality energy available from an energy resource is its net energy yield.​

Approximately 87% of the world’s commercial energy comes from fossil fuels.​

The nuclear fuel cycle has a low net energy yield.​

Nuclear fission is a process where the nuclei of two isotopes of a light element are forced together at an extremely high temperature until they fuse to form a heavier nucleus with a release of energy that can be used to produce commercial energy.​

A spent fuel rod is one that has lost all of its radioactivity

The nuclear fuel cycle has a low net energy yield.​

Hydropower has a low net energy yield

Production and delivery of natural gas may emit more CO2 and CH4 per unit of energy produced than the burning of coal for commercial energy.​

​Crude oil is also known as light crude or conventional oil.

Production of fossil fuels from shale rock has a lower net energy yield than does the fossil fuel produced from conventional oil deposits.

Aside from increasing energy efficiency, what energy resource has the highest net energy ratio for space heating?

What energy resource has the highest net energy ratio for transportation?

What is bitumen?

What is the term for propane and butane gases that can be liquefied under high pressure during the production of natural gas?

What is the world's most abundant nonrenewable fossil fuel?

The nuclear fuel cycle can last up to ____ years.

A small pellet of uranium dioxide is about the size of an eraser on a pencil and contains the energy equivalent to a ____.

What is an advantage of solar cells?

The leading renewable energy resource that is used to produce electricity in the world today is ____.

The world’s second fastest-growing source of electricity after solar cells has been ____.