Earth’s Four Spheres
Water, Water Everywhere
Rock Stars
Water Under Threat
Weather Watch
100

This Earth system contains all of Earth’s water.

What is the hydrosphere?

100

About seven-tenths of Earth’s surface is covered by this substance.

What is water?

100

Earth’s uppermost rocky layer, the one we live on, is called this.

What is the crust?

100

Water that has already been used by people is called this.

What is wastewater?

100

Almost all of Earth’s weather occurs in this lowest layer of the atmosphere.

What is the troposphere?

200

This Earth system contains all of Earth’s rocky layers, rocks, and minerals.

What is the geosphere?

200

This is water stored in spaces between rocks and other materials beneath Earth’s surface.

What is groundwater?

200

The three major rock types are igneous, sedimentary, and this third type.

What is metamorphic rock?

200

Wastewater is cleaned at this type of facility before being released into the environment.

What is a water treatment plant?

200

This instrument measures air pressure.

What is a barometer?

300

This Earth system is made of the gases surrounding Earth.

What is the atmosphere?

300

A place where water collects is called this.

What is a reservoir?

300

Magma that reaches Earth’s surface is called this.

What is lava?

300

This process is the final major cleaning step in which chemicals kill bacteria and other germs.

What is disinfection?

300

As altitude increases, air pressure generally does this.

What is decrease?

400

This Earth system includes every living thing on Earth.

What is the biosphere?

400

Water with more salt than fresh water but less salt than ocean water is called this.

What is brackish water?

400

Rock changed by intense heat and pressure becomes this type of rock.

What is metamorphic rock?

400

Too much of this chemical from fertilizers and soaps can cause algae to grow out of control.

What is phosphate?

400

Warm air tends to rise while this type of air tends to sink.

What is cool air?

500

A rainstorm waters plants, erodes soil, and later evaporates into the air. Name the four Earth systems involved.

What are the hydrosphere, biosphere, geosphere, and atmosphere?

500

Evaporation, condensation, precipitation, gravity, and water movement are all parts of this continuous process.

What is the water cycle?

500

This continuous process describes rock changing among igneous, sedimentary, and metamorphic forms.

What is the rock cycle?

500

Explain why an algal bloom can cause fish to die even though algae are living organisms in the food chain.

What is: dying algae lead to increased bacteria, which use up dissolved oxygen, leaving too little oxygen for fish?

500

Which weather conditions are generally associated with low pressure, and which are associated with high pressure?

What are clouds, wind, and precipitation for low pressure; clear skies and calm winds for high pressure?