Global Systems

Question 1

Ocean Current

Answer 1

Continuous movements of ocean water that circulate around the Earth and determine weather and climate. They can be found deep underwater or on the surface.

Question 2

What causes ocean currents?

Answer 2

They are caused by wind, temperature, variations in salinity, the rotation of the Earth, and the gravitational pull of the Sun and Moon.

Question 3

What is the correlation between location of a current and its temperature?

Answer 3

Currents originating in lower latitudes (near the equator) carry warmer water while currents originating in higher latitudes (closer to the north and south pole) carry colder water.

Question 4

What is the correlation between the location of a current and its salinity?

Answer 4

The higher the salinity, the denser the water, therefore the deeper the current is while the lower the salinity, the lighter the current, therefore making it a surface current.

Question 5

Define the Global Conveyor Belt/Thermohaline Circulation

Answer 5

Water cycling from deep currents to surface currents, to deep again that distributes heat around the globe. A combination of currents that connect the oceans.

Question 6

What is Australia’s extreme weather caused by?

Answer 6

The Southern Oscillation, El Nino, and La Nina.

Question 7

Southern Oscillation

Answer 7

A sequence of changes to the way the atmosphere and water circulate across the Pacific Ocean and Indonesian Islands. It is also a measure of the atmospheric and ocean conditions across the Pacific Ocean.

Question 8

What does the Southern Oscillation Index tell us?

Answer 8

Close to zero SOI = conditions are normal
Strongly negative SOI = El Nino
Strongly positive = La Nina

Question 9

El Nino

Answer 9

The warm phase of the Southern Oscillation. Occurs when sea surface temperatures in the central and eastern Equatorial Pacific become warmer than average. When it occurs it means more energy for storms to form. It also weakens trade winds which allows warmer water from the eastern Pacific to surge eastward.

Question 10

La Nina

Answer 10

Climate La Nina impacts tend to be directly opposite of El Nino impacts. Occurs when the central and eastern Pacific sea surface temperatures become cooler than average. Equatorial trade winds become stronger which draws the cooler deep water from below and changes ocean surface currents.

Question 11

Impacts of El Nino

Answer 11

• Reduced rainfall
• Warmer temperatures
• Increased frost risk
• Increased fire danger in southeast Australia

Question 12

Impacts of La Nina

Answer 12

• Increased rainfall and cloudiness
• Cooler temperatures
• Decreased frost risk
• Stronger winds among the equatorial region
• Greater tropical cyclone numbers

Question 13

Indian Ocean Dipole

Answer 13

A cycle of change in the water temperature between the eastern and western areas of the Indian Ocean (near the equator).

Question 14

Weather

Answer 14

The state of the atmosphere in terms of temperature, wind, cloud cover, and precipitation.

Question 15

Climate

Answer 15

The long term averages of weather conditions.

Question 16

Atmosphere

Answer 16

Layer of gases (commonly known as air) that surrounds the Earth and is retained by Earth’s gravity.

Question 17

What are the 4 layers of the atmosphere?

Answer 17

The atmosphere is comprised of layers based off temperature which are the troposphere, stratosphere, mesosphere, and thermosphere.

Question 18

Biosphere/Ecosphere

Answer 18

The life support system of our planet including all of the Earth’s ecosystems and the atmosphere, lithosphere, hydrosphere and biota (living things).

Question 19

Lithosphere

Answer 19

The rigid outer part of the Earth where igneous, sedimentary, and metamorphic rocks are formed. Made up of Earth’s rocky crust and soil.

Question 20

Gulf Stream

Answer 20

Part of the Global Conveyor Belt. 10 000 km long, making it the largest and fastest warm ocean current on Earth. It brings warm water and air from the Gulf of Mexico into the Atlantic Ocean.

Question 21

Calcium Carbonate (CaCO3)

Answer 21

A chemical found in limestone (the largest carbon sink) and is Earth’s largest and oldest long-term store of carbon.

Question 22

Nitrogen - Fixation

Answer 22

Nitrogen-fixing microorganisms (bacteria and other single-celled prokaryotes) convert atmospheric nitrogen into ammonia and nitrates which is more of a biologically usable form that can then be taken up by plants through the soil.

Question 23

Ammonification

Answer 23

After an organism dies and gets decomposed (digested by bacteria) bacteria is able to break the nitrogenous compounds down and reverse it to ammonia.

Question 24

Nitrification

Answer 24

When ammonia is converted into nitrates by nitrifying bacteria.

Question 25

Haber Process

Answer 25

Artificial nitrogen-fixation process that produces ammonia from nitrogen and hydrogen.

Question 26

How do thunderstorms impact the nitrogen cycle?

Answer 26

During electrical storms, the energy of lightning breaks nitrogen molecules in the atmosphere into nitrogen atoms that then combine with the oxygen into the air forming nitrogen oxides (nitrates). These then dissolve in the rain and enter the soil as nitrates plants can use.

Question 27

Cellular Respiration

Answer 27

The process through which cells convert fuel into energy and nutrients.

Question 28

Leguminous Plants

Answer 28

Plants that produce seeds such as peas, beans, wattles, etc.

Question 29

Rhizobium

Answer 29

A type of nitrogen-fixing bacteria.

Question 30

Define the relationship between Leguminous plants and the bacteria Rhizobium.

Answer 30

They live in a symbiotic where they depend on each other for survival. Rhizobium bacteria live in the root nodules of the plant and gain protection and glucose while the leguminous plants gain nitrates and contain more protein than other plants because of the location of the nitrates.

Question 31

Evaporation

Answer 31

Water on the surface of the Earth is absorbed by the Sun’s heat energy and converted to water vapour.

Question 32

Condensation

Answer 32

Water vapour in the air is changed into liquid water and is responsible for the formation of clouds.

Question 33

Precipitation

Answer 33

The clouds (condensed water vapour) pour down as precipitation due to wind or temperature change. This occurs because water droplets combine to make bigger droplets.

Question 34

Transpiration

Answer 34

As water precipitates, it is then turned into water vapour by plants when the roots of the plants absorb the water and push it to the plants as photosynthesis. Essentially is the evaporation of water from plant leaves.

Question 35

Infiltration

Answer 35

Some of the water that does not runoff into the rivers or evaporates but moves deep into the soil and becomes pure water.

Question 36

Denitrification

Answer 36

Bacteria (that is not exposed to oxygen) takes nitrates and breaks them down into nitrites and then nitrogen gas which is released back into the atmosphere as nitrogen gas (atmospheric nitrogen).

Question 37

How do greenhouses heat up?

Answer 37

Short-wave radiation comes from the Sun which is absorbed by clouds and the Earth’s surface and then radiated back into space as long-wave radiation (heat). That long-wave radiation cannot pass back through the glass (atmosphere) and gets trapped causing the temperature to increase.