Chapter 10 Test Study Notes

Question 1

Why is some water salty?

Answer 1

The reason why some water is salty is because the concentration of dissolved salts in ocean water averages 3.5 percent.

Question 2

Why is some water fresh?

Answer 2

The reason why some water is fresh is because it contains dissolved salts, but in amounts of less than 1 percent.

Question 3

What does salinity refer to?

Answer 3

Salinity refers to how much salt is dissolved in water.

Question 4

Where is the groundwater zone?

Answer 4

This freshwater storage zone exists in all soils, but the depth differs from region to region.

Question 5

What’s a water table?

Answer 5

The upper surface of the groundwater zone is called the water table.

Question 6

What’s an aquifer?

Answer 6

An aquifer are rocks and soil layers in the ground which exist in such a way that allows large amounts of water to collect within them naturally.

Question 7

What are wells?

Answer 7

Most rural homes and small farms drill and use wells, which are long, hollow shafts, down into aquifers to obtain fresh water.

Question 8

What’s an ice sheet?

Answer 8

An ice sheet is a particularly large glacier that covers the land. Only two of these huge glaciers exist on Earth, one in Greenland and one in Antarctica.

Question 9

What’s a polar icecap used to refer to?

Answer 9

The term polar icecap is sometimes used to refer to the big ice masses at the poles.

Question 10

What’s a watershed?

Answer 10

A watershed is an area of land where all the water eventually drains into one main water body, such as a stream, river, wetland, lake, or ocean. Activities that affect water in one part of the watershed therefore have an effect downstream in the watershed.

Question 11

What’s heat capacity and what does it refer to?

Answer 11

Heat capacity refers to the ability of a material to absorb heat. When testing a material’s heat capacity, scientists measure how long the material takes to heat up (absorb heat) and cool down (release heat).

Question 12

What are the three states of water?

Answer 12

Liquid, solid, gas.

Question 13

Where is liquid water found?

Answer 13

Liquid water is found both above and below the ground.

Question 14

What’s surface water and how is it collected?

Answer 14

Surface freshwater is the water in rivers, streams, lakes, ponds, and wetlands (such as marshes and swamps). In many communities, fresh water is also collected in human-made reservoirs such as artificial lakes and water towers. Precipitation (such as rain and snow) helps keep these water bodies filled.

Question 15

How is water collected underground naturally?

Answer 15

Underground water is called groundwater. As rainwater falls, it soaks into the soil and flows down between the soil particles. Slowly it continues draining downward through more soil and rocks until it reaches a layer that is difficult to permeate (meaning pass through). The upper surface of the groundwater zone is called the water table.

Question 16

What’s solid water?

Answer 16

All of the solid (frozen) water on Earth is freshwater. Ocean water can freeze, but salt water requires a lower temperature than freshwater does to become ice. In Earth’s polar regions and on the tops of its high mountains, most fresh water exists in a solid state of ice and snow.

Question 17

What are mountain glaciers?

Answer 17

In many mountain regions, temperatures are below freezing much of the year and the snow that falls never gets a chance to melt. A glacier is a mass of ice and overlying snow that moves slowly down a mountain slope under the influence of gravity.

Question 18

What are ice shelves?

Answer 18

An ice sheet forms in the same way as a mountain glacier does, but on a much larger scale. The floating ice is called an ice shelf. Large sections of an ice shelf that break off are called icebergs. As they float, icebergs change shape, and roll over, eventually melting.

Question 19

What’s gaseous water?

Answer 19

Water also exists in a gaseous state in the atmosphere. When liquid water evaporates from oceans, lakes, and rivers, it forms water vapor. You cannot see water vapor, but you can feel it as humidity in the air. As water vapor is carried upwards into the atmosphere, it becomes colder and condenses into droplets of water that form clouds. Plants and animals also put water vapor into the atmosphere.

Question 20

What is transpiration?

Answer 20

Transpiration is the process of water evaporation from plant leaves. Animals also exchange water vapor during respiration (breathing).

Question 21

What’s the cycling nature of water?

Answer 21

The water on Earth is always changing its state. Figure 10.13 shows the processes by which water changes state as it moves from Earth’s surface into the atmosphere and back to Earth again. This non-stop circulation is called the water cycle. The Sun provides the thermal energy that drives the whole cycle.

Question 22

What are watersheds and how do they work?

Answer 22

We all live in an area that is part of a water drainage basin known as a watershed. If you put your boat in a river in Jasper, Alberta, it would end up in the Arctic Ocean. Many smaller watersheds connect to other larger watersheds and finally empty into an ocean. As water cannot flow uphill, high points in the land such as mountain ridges create natural “divides.” Mountain chains or especially long areas of high land mark the boundaries of major watersheds on the continents. For example, the Rocky Mountains act as a divide and are often referred to as the Great or Continental Divide. If you are west of the Rockies, much of the water flows to the Pacific Ocean. If you are on the east side, it flows to the other main watersheds.

Question 23

How does water moderate air temperature?

Answer 23

As you may recall from previous studies, Earth is surrounded by an atmosphere made up of a mixture of gasses, including water vapor. This atmospheric layer extends for many kilometers above the planet. Heat from the sun passes through the atmosphere, reaching Earth’s surface. The amount of energy absorbed at any location depends on what is at the surface.

Question 24

How does land and water absorb heat from the Sun?

Answer 24

The land absorbs heat from the Sun more quickly than the water does. The air over the land becomes warmer as some of this absorbed heat is radiated back into the air. The warmer air begins to rise, and the cooler air over the water moves in to take its place.

As the Sun goes down, the land cools off quickly, but the water does not. The water radiates some of its stored heat into the air, and this warmed air begins to rise. The cooled air over the land moves in to take the place of the rising warm air over the water.

Question 25

What's the relationship between water bodies and regional climate?

Answer 25

In every part of the world, the presence of large water bodies is a major contributor to climate differences experiences from region to region. The Great Lakes are also notable for the strong moderating effect they have on the climate of the areas that border them. Their extensive water masses keep both summer and winter temperatures moderate. They also provide large amounts of moisture to the air. In the winter, this moisture eventually falls as snow. The heaviest snowfalls anywhere in Ontario occur in the stretch of land that extends east from Lake Huron and up to Georgian Bay.

Question 26

How do global climates affect temperature differences based on land to ocean ratio?

Answer 26

The northern hemisphere is 39% land and 61% ocean. The southern hemisphere is 19% land and 81% ocean. Because of the greater proportion of water surface south of the equator, the moderating effect on that hemisphere's climate is notably greater than on the northern hemisphere's climate. In the southern hemisphere annual average temperatures vary by only about 7.3 C from summer to winter. In the northern hemisphere, they differ by around 14.3 C.

Question 27

What's a microclimate?

Answer 27

A microclimate is an area with a small, localized climate variation that differs from the larger climate area around it. These differences in climate can occur over a very small scale. Inside a greenhouse, for example, can be a microclimate that is much warmer and moisture than the climate outside.

Question 28

How do most glaciers end up melting?

Answer 28

You read in Section 10.1 about how glaciers form. Where temperatures on Earth are below freezing, precipitation falls as snow. When snow builds up over time, it creates glaciers. If the cold conditions continue, the glaciers continue to grow larger and spread. On the other hand, if temperatures begin to rise and annual precipitation patterns change, glaciers start to shrink in size. Warmer temperatures mean that precipitation, even on mountaintops, is likely to fall as rain instead of snow. At the same time, the warmer temperatures cause the existing glaciers to melt. When they begin getting smaller in size, they are said to be receding or retreating.

Question 29

How do ice changes affect water systems?

Answer 29

When mountain glaciers and ice sheets increase in size, it means that even less water is available to be part of the world's oceans, atmosphere, and other water systems. Extreme examples of this occur during ice sheet expansion. Scientists estimate that with nearly a third of the planet covered in thick ice during the last expansion, seas levels on Earth were more than 100m lower than they are now. Figure 10.24 shows the extent of what was known as the laurentide ice sheet that once covered Canada. The opposite happens when glaciers and ice sheets shrink. Their frozen water is released in liquid and gaseous states. The melting glaciers slowly add more fresh water into the streams, rivers, and lakes they empty into. In turn, these bodies of water empty into oceans, adding to the volumes there. The increased amount of fresh water dilutes the seawater, reducing the salinity of the surrounding ocean water.