Water Systems

Question 1

What is most of the water on earth?

Answer 1

Salt water

Question 2

What percentage of the earth’s water is salt water?

Answer 2

97

Question 3

What percentage of the earth’s water is fresh water?

Answer 3

2.6

Question 4

What percentage of the earth’s water is in ice caps?

Answer 4

67

Question 5

What percentage of the earth’s water is ground water?

Answer 5

30

Question 6

Is water a renewable resource?

Answer 6

It depends on where it is stored. In oceans, no, in rivers, yes.

Question 7

What drives the water cycle?

Answer 7

Gravity and solar radiation

Question 8

What are water transfers?

Answer 8

Advection
Flooding 
Surface run off
Infiltration
Stream flow and current

Question 9

What are water cycle transformations?

Answer 9

Evotranspiration
Condensation
Freezing

Question 10

Storages of water?

Answer 10

Oceans
Soil
Groundwater
Lakes
Rivers and streams
Atmosphere
Glaciers and ice caps

Question 11

What are human impacts on the water cycle?

Answer 11

Withdrawals
Discharges
Changing the speed of water flow
Diverting rivers

Question 12

What are withdrawals of water?

Answer 12

for domestic use, irrigation and industry

Question 13

What are discharges of water?

Answer 13

Adding pollutants to the water

Question 14

How can humans change the speed of water?

Answer 14

1. Building roads and channelling rivers underground
2. Canalizing
3. With dams

Question 15

What is canalizing?

Answer 15

Straightening large sections of rivers in concrete channels

Question 16

Why would humans divert rivers?

Answer 16

To avoid flood damage rivers are diverted from important areas.
Some are also diverted towards dams to improve storage.

Question 17

What are examples of major changes caused by humans?

Answer 17

The aral sea

The ganges basin

Question 18

What happened in the aral sea?

Answer 18

irrigation decreased river flow into the sea which lowered the sea level. It decreased by 90%.

Question 19

What are surface currents?

Answer 19

currents moved by the wind

Question 20

What are deep water currents?

Answer 20

caused by differences in water density

Question 21

How does density in sea water work?

Answer 21

warm water can hold less salt than cold water so its less dense and rises. The cold water sinks. When warm water rises, cold water has to come up and replace it. When cold water rises, warm water has to go down and replace is. Thus, water circulates.

Question 22

How can ocean currents effect climates?

Answer 22

Since water has a higher heat capacity than land, water masses heat up and cool down more slowly than landmasses. Land closer to seas therefore has a mild climate with moderate winters and cool summers.