ESS

Question 1

Earth Systems

Answer 1

The Earth is made up of 4 distinct yet connected systems: atmosphere, biosphere, lithosphere, and the hydrosphere.

Question 2

Atmosphere

Answer 2

The layer of gases surrounding the Earth

Question 3

Biosphere

Answer 3

The part of the Earth composed of all the living organisms on the planet including plants, animals, bacteria, etc.

Question 4

Lithosphere (geosphere)

Answer 4

The part of the Earth composed of all the rocks, minerals, molten magma found on the surface and underground. Includes only non-living stuff

Question 4

Interaction

Answer 4

These spheres interact together to influence factors such as landscape, soil formation, change in temperature, biodiversity, and salinity. For example, the interaction of spheres influence temperature differences. The mountain ranges of the lithosphere interact with the low air pressure of the atmosphere and the snowy precipitation of the hydrosphere to produce an icy climate. This climate drives adaptations vital for organisms of the biosphere.

Question 5

Hydrosphere

Answer 5

The part of the Earth composed of all the water (solid, liquid, and gas) on Earth.

Liquid water (oceans, rivers, lakes, underground, etc), solid water (ice caps, glaciers, etc), and water vapour (clouds, rain, snow, etc)

Cryosphere – frozen water part of Hydrosphere

Question 6

The carbon cycle

Answer 6

The path through which carbon is exchange between the 4 Earth Spheres by the processes of respiration, combustion, photosynthesis, decomposition, and fossilisation.

Question 7

Respiration

Answer 7

The process of producing energy from sugar and oxygen and releasing CO2 and water in the process.

Question 8

Combustion

Answer 8

Combustion is a high temperature chemical reaction between a fuel and an oxidant, producing Carbon dioxide and water in the process.

Question 9

Photosynthesis

Answer 9

The process where green plants and certain other photosynthetic organisms transform carbon dioxide, water, and sunlight into oxygen and glucose.

Question 10

Decomposition

Answer 10

Decomposition is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts.

Question 11

Fossilisation

Answer 11

Fossilisation is the process of an animal or plant dying off and lithifying to form rock, storing carbon for long periods of time. Carbon is released back into the atmosphere when the fuel is burned.

Question 12

How is Carbon cycled in the 4 Earth Spheres?

Answer 12

Carbon dioxide in the atmosphere is converted into glucose and oxygen during photosynthesis by plants, moving from the atmosphere to the biosphere. These plants respire which releases Carbon dioxide back into the atmosphere and also pass on Carbon to animals as they feed on it. When a plant or animal dies, they decompose which releases Carbon dioxide back into the atmosphere or fossilise to form rocks which is a part of the lithosphere, storing carbon for long periods of time before being burned and releasing Carbon dioxide back into the atmosphere. Marine plants and animals of the hydrosphere also conduct these processes.

Question 13

Weather

Answer 13

Weather is the short-term change in atmosphere with respect to its effects on life form and human activities. It is thought of in terms of wind, temperature, precipitation, storm, humidity, etc.

Question 14

Climate

Answer 14

Climate describes the predominant long-term pattern in weather in a particular region.

Question 15

The natural greenhouse effect

Answer 15

The natural process that maintains Earth’s ideal surface temperature for plants and animals. When solar radiation from the sun reaches the Earth’s atmosphere, which includes heat in the form of infrared waves, some of it is reflected back to space, some of it is absorbed by the land and oceans, and some are trapped by greenhouse gases.

Greenhouse gases (GHGs) include: carbon dioxide, water vapour, methane, ozone, and nitrous oxide.

Question 16

The greenhouse effect in cars

Answer 16

Solar radiation which includes visible light passes through a car glass/window due to its short wavelengths. Some of it is reflected back out but some are absorbed and re-radiated in longer wavelengths in the form of infrared waves which is heat. Infrared waves are unable to escape through glass and hence is trapped.

Question 17

Thermohaline circulation

Answer 17

Deep-ocean currents driven by differences in water density due to differences in temperature and salinity.

Ocean water in polar regions gets very cold and forms sea ice which leaves salt behind. The surrounding cold and salty ocean water sinks as density increases until it can rise to the surface near the equator. Warm and less salty surface water from the equator is pulled in to replace the sinking water, which in turn eventually becomes cold and salty enough to sink. This creates the deep-ocean current and global conveyer belt that help redistribute heat around the globe.

Question 18

Gyres

Answer 18

A large system of swirling surface currents, driven by the Coriolis effect in wind, tides, and differences in temperature and salinity. These currents help redistribute heat and warmth around the globe.

Question 19

carbon sink

Answer 19

A carbon sink is any feature of the environment that absorbs and/or stores carbon, keeping it from the atmosphere.

4 main carbon sinks:

Soil: contains organic matter and decomposed organic matter of fossil fuels

Forest/plants: take in large amounts of Carbon dioxide via photosynthesis

Rocks: contains limestone, chalk, and carbonates

Oceans: contains dissolved CO2 and carbonates in shells of marine organisms

Question 20

Global climate is influenced by a number of factors, including:

Answer 20

Latitude and the Earth’s tilt, Surface covering (water, land, ice, vegetation), Topography (mountains, plains)

Question 20

Climate change

Answer 20

Climate change refers to major changes in the predominant long-term patterns of weather caused by natural variability and human activity.

Question 21

Evidence of climate change in geological past

Answer 21

Fossilized plants and animals that normally live in certain environments have been found at much higher or lower latitudes than they could survive at today. This serves as evidence that climate change occurred in different parts of the globe.

Ice-ages: a period in Earth’s history when the ice on the polar caps significantly expands due to a lowering of the Earth’s global temperatures.

Inter-glacial periods: a period of warmer temperatures between ice ages where glaciers retreat and sea levels rise.

Natural causes include changes in the Earth’s orbit, the intensity of the sun, the circulation of the ocean and the atmosphere, and volcanic activity.

Question 22

Latitude and the Earth’s tilt

Answer 22

At the equator, the sun’s rays are perpendicular to the Earth’s surface, exposing it to more heat.

At the poles, the sun’s rays are spread across a wider area, heating it up less than at the equator.

Global winds are caused by differences in atmospheric pressure due to the uneven heating of the Earth by the sun. Wind carries heat, moisture, pollutants and pollen to new areas.

Earth’s tilt causes six-month winter difference in northern and southern hemisphere.

Question 23

Surface covering (water, land, ice, vegetation)

Answer 23

Coastal areas: The sun heats the land more quickly than water. Warm air above the land rises and cooler air above the water moves in over the land, creating an inland breeze. The opposite goes during winter, water retains more heat and warm air above it rises and cooler air above the land moves in over the water, creating a land breeze.

Reflection of Surfaces: Different surfaces reflect different amounts of heat and light. (Surfaces without snow or ice absorbs more heat while surfaces with snow and ice reflects more heat.)

Question 24

Topography (mountains, plains)

Answer 24

It is the physical features of an area

Mountainous Areas: As wind approaches a mountain, it brings moisture with it, which condenses as rain before coming over the crest of the mountain. The dry air after rain moves downslope the mountain, creating rain shadows on the other side of the mountain.

Question 25

Describe the enhanced greenhouse effect

Answer 25

The impact on the climate from the additional heat retained due to the increased amounts of carbon dioxide and other greenhouse gases due to human activity.

Question 26

Sources of Anthropogenic GHGs

Answer 26

Energy production in burning fossil fuels, transportation of vehicles, agriculture producing methane from livestock and land grazing, etc.

Question 27

Sources of Anthropogenic GHGs

Answer 27

Energy production in burning fossil fuels, transportation of vehicles, agriculture producing methane from livestock and land grazing, etc.

Question 28

List fossil fuel types and compare their relative contributions to GHG emissions

Answer 28

Fossil fuels

a hydrocarbon-containing material such as coal, oil, and natural gas, formed naturally in the Earth’s crust from the remains of dead plants and animals.

1. Coal (40 per cent)

Petrified remains of plants

Flammable, easily transportable and mined (solid)

2. Oil (32 per cent)

Gasoline, diesel, motor oil, etc

3. Gas (21 per cent)

Methane, ethane, propane, butane, etc

Question 29

Investigate the role of the Aboriginal fire management regime in reducing GHG emissions

Answer 29

Aboriginal fire management involves cool burning during the early dry season. The man-made fires burn gradually removing fuel for larger fires during the late dry season which release Carbon dioxide to the atmosphere and to protect habitats. This method is an opportunity for collaborations to encourage Aboriginal empowerment with public and private sector organisations.

Question 30

Describe the abiotic effects of Climate Change:

Answer 30

1. Temperature changes

Increased level of greenhouse gases in the atmosphere due to human activity increase surface temperatures as more solar radiation is trapped on Earth. The average global temperature on Earth has increased by 1 C since 1880.

2. Extreme weather events

Changes in temperature, rainfall pattern and sea levels lead to floods, fires, storms, drought, etc.

3. Melting ice caps

As ice caps melt, reflection of the sun’s radiation is reduced leading to an increase in ocean temperatures as they absorb more heat. Sea level rises as well which causes destructive coastal inland erosion and soil contamination with salt.

4. Thermohaline circulation disruption

Warming surface waters and melting ice caps that add fresh water make waters less saline and warmer, preventing it from sinking and result in weaker currents. Hence, causing widespread cooling especially in the North-Atlantic regions.

Question 31

Describe the impact of ocean acidification on the great barrier reef

Answer 31

Biodiversity and abundance of reef-associated organisms are adversely affected. Coral calcification has slowed and growth in seaweed compete for space with corals. High CO2 levels lead to reefs dominated by massive corals as well. Crabs, shrimps, and mussels lose their habitat of branching coral and fish behaviour is also impacted, increasing the risk of mortality of some species of these marine animals.

Question 32

Describe changing environments, desertification and habitat loss in polar and alpine ecosystems

Answer 32

Changing environments of rising surface temperatures, melting of ice and rising sea levels lead to desertification and habitat loss. Desertification and soil degradation of alpine regions are caused by reduced rainfall and increased evaporation. Habitat loss in polar regions by melting sea ice while in alpine areas, the shift in vegetation to higher altitudes disrupts the balance of flora and fauna.

Question 33

Define extinction

Answer 33

All members of a species are diminished because of environmental forces. Populations that can’t migrate to adhere to effects of climate change, mostly plant and insect species, eventually die off and are at risk of becoming extinct.

Question 34

Describe the effects on species and genetic biodiversity

Answer 34

Climate change which lead to bushfires, heatwaves, droughts, floods, rise in sea levels, and ocean acidification lead to elimination of species in certain areas as they cannot adapt to the effects of climate change.

Climate change can lead to selective pressures on species, influencing the genetic diversity within populations. Species with limited genetic diversity may struggle to adapt to rapid environmental changes and make them more susceptible to diseases.

Question 35

Describe the value of biodiversity (ecosystem resilience, human resources for food, medicines)

Answer 35

Biodiversity is essential for the production of ecosystem services such as maintaining soil fertility, supply of clean water, nutrient cycling, and pollination which increases an ecosystem’s resilience and bring economic, cultural, recreational and scientific values.

Ecosystem resilience: an ecosystem’s capacity to absorb both natural and human caused disturbance such as climate change and maintain its normal patterns of ecosystem services.

Economic value includes both the intrinsic values of ecosystems and biodiversity and the market values of goods provided such as food, water, etc.

Cultural value includes the knowledge, sense of belonging and past traditions of the country and place, which is important to Indigenous people especially.

Recreational value includes interactions and activities involved with the appreciation of the natural environment

Scientific value includes the ability of scientists to undertake experiments and studies on different plants and animals to generate new crops, medicine, and study the evolution of certain species.

Question 36

Describe the role of natural ecosystems in maintaining weather patterns and providing human resources such as fishing, tourism and wood

Answer 36

Natural ecosystems maintain weather patterns by acting as buffers against extreme weather and provide fishing, tourism, and wood to humans.