Bill Nye: Oceanography

According to the water cycle, water moves from the ocean to the atmosphere and back again.  Why isn't rain water salty?

• the salt falls as ice and snow from the clouds, never as rain

• the wind and currents prevent the salt from entering rainwater

• the water evaporates, salt doesn't because the salt is too heavy

Which water will taste saltier? 

• The one on the right

• The one on the left

Salt water is. . .

• less dense than fresh water, so it floats

• less dense than fresh water, so it sinks

• more dense than fresh water, so it floats

• more dense than fresh water, so it sinks

Oceans are salty and rivers and lakes aren't because...

• the salt is created by the ocean's wave action.

• the salt is eroded by water in rivers and lakes and is carried away from rivers and into the sea.

• salt is created in the ocean when sea creatures die, giving off their salt into the water.

Which is true? 

• The oceans are getting saltier because of all the salt and mineral runoff from rocks in rivers and lakes.  

• The oceans are getting less salty.

• The level of salt in the ocean is mostly constant.

What makes water in the ocean move in ocean currents? (What is the source of energy?)

• rain

• the sun

• the Earth's angle

• underwater volcanoes

Ocean currents in the Northern Hemisphere flow mostly _____________. Ocean currents in the Southern Hemisphere flow mostly _____________. 

 

• clockwise, counter clockwise

• counter clockwise, clockwise

What is the most powerful current in the world?

• the Gulf Stream

• the Atlantic Current

• the Pacific Current

Water at the equator is heated by the sun. It expands and flows toward the _______.

• equator

• poles

If ocean currents stopped flowing, how do you think it would change the climate?

• just a little bit

• drastically (a lot)

• not at all