Where did Earth’s water come from?

• It spontaneously popped up from the crust

• Outer space

• There are no theories of where it came from

Tags

NGSS.HS-ESS2-5

Earth’s water evolved in which way?

• It has always been liquid water

• It came to earth as liquid, but the early cold Earth froze it into solid ice

• It came as a gas, but turned to liquid as the early hot Earth cooled

Tags

NGSS.MS-ESS2-4

Evaporation in the water cycle is:

• Liquid water on Earth’s surface changes into a gas from the Sun’s energy.

• Gas water molecules get closer and form tiny droplets in clouds.

• Liquid water (rain) or solid water (snow) falls back to Earth’s surface.

• Some water travels over the surface into streams, rivers, lakes and the ocean.

• Some water soaks into the ground and is stored.

Tags

NGSS.MS-ESS2-4

Infiltration in the water cycle is:

• Liquid water on Earth’s surface changes into a gas from the Sun’s energy.

• Gas water molecules get closer and form tiny droplets in clouds.

• Liquid water (rain) or solid water (snow) falls back to Earth’s surface.

• Some water travels over the surface into streams, rivers, lakes and the ocean.

• Some water soaks into the ground and is stored.

Tags

NGSS.MS-ESS2-4

Precipitation in the water cycle is:

• Liquid water on Earth’s surface changes into a gas from the Sun’s energy.

• Gas water molecules get closer and form tiny droplets in clouds.

• Liquid water (rain) or solid water (snow) falls back to Earth’s surface.

• Some water travels over the surface into streams, rivers, lakes and the ocean.

• Some water soaks into the ground and is stored.

Tags

NGSS.MS-ESS2-4

Runoff in the water cycle is:

• Liquid water on Earth’s surface changes into a gas from the Sun’s energy.

• Gas water molecules get closer and form tiny droplets in clouds.

• Liquid water (rain) or solid water (snow) falls back to Earth’s surface.

• Some water travels over the surface into streams, rivers, lakes and the ocean.

• Some water soaks into the ground and is stored.

Tags

NGSS.MS-ESS2-4

Condensation in the water cycle is:

• Liquid water on Earth’s surface changes into a gas from the Sun’s energy.

• Gas water molecules get closer and form tiny droplets in clouds.

• Liquid water (rain) or solid water (snow) falls back to Earth’s surface.

• Some water travels over the surface into streams, rivers, lakes and the ocean.

• Some water soaks into the ground and is stored.

Tags

NGSS.MS-ESS2-4

Two ways that the water cycle “cleans” water and makes it usable freshwater.

• Precipitation and runoff

• Evaporation and runoff

• Condensation and infiltration

• Evaporation and infiltration

Tags

NGSS.MS-ESS2-4

About how much (what percent) of the water on Earth is unusable (locked up in salt water)?

• 97 - 98% (a lot)

• 100% (all)

• 0% (none)

• 50% (about half)

About what percent of Earth’s water is usable or freshwater?

• about 3% (very little)

• 100% (all)

• 0% (none)

• 50% (about half)

Tags

NGSS.MS-ESS2-4

NGSS.MS-ESS3-1