Evidence, Effects and Impacts of Climate Change

Question 1

What event indicated the beginning of the Little Ice Age?

Answer 1

Unseasonal cold weather around 1300, cold summers and storms at the time of the Spanish Armada.

Question 2

When did the Little Ice Age occur?

Answer 2

1400 to 1850 AD

Question 3

How much cooler were the temps in the Little Ice Age compared to today?

Answer 3

-2°C to -3°C on average less than the present.

Question 4

Describe some of the effects of the Little Ice Age.

Answer 4

People froze to death
Birds died on the wing
Growth of glaciers closer to settlements
Crop failures
Freezing of rivers (Thames frost fair) and harbours (New York)
Great famines
Food prices rose
Wages of farm workers increased
Increase in crime
Accusations of witchcraft (50,000 executions)

Question 5

What is the importance of the Little Ice Age to climatologists?

Answer 5

Part of a recurring cycle.

Question 6

How do ocean sediments assist in understanding past climate conditions?

Answer 6

Ratio of species of organisms (foraminifera).
Some are suited to warm conditions, some to cold conditions.
Direct relationship to temp.
Little Ice Age averaged 4°C colder than today.

Question 7

Describe the period called the Little Climate Optimum (medieval warm period).

Answer 7

Allowed for greater prosperity. 
Temps suited for agriculture.
Crops more reliable.
Malaria on the decline.
Population increased 40-60 million.

Question 8

How did the Little Ice Age affect human development?

Answer 8

Population became more susceptible to disease and declined.

Question 9

Describe the onset of the Little Ice Age.

Answer 9

Winter periods became longer and colder.
Glaciers did not retreat in summer.
Increase in the Arctic ice pack.

Question 10

List the catastrophes that occurred in Europe in the 14th Century.

Answer 10

1315 (for 5 years) - heavy rain from the Urals to Ireland and destroyed marginal crops.
1371-1791 – 111 famines in France.
1601 - Russian famine killed 500,000.

Question 11

Why was the choice of crops dangerous to the peasant’s food supply?

Answer 11

Cereal crops better for warmer periods and easily destroyed by cold.

Question 12

Describe the effects of the famine on the population and its relation to climate.

Answer 12

High death rates (500,000 in Russia).
Families killed some children to preserve enough food for the rest.
Malnutrition and bubonic plague.

Question 13

What were the results of the Black Death?

Answer 13

25 million or one-third of Europe’s population died.

Question 14

How did the Little Ice Age affect the Viking Colonies in Greenland?

Answer 14

Colonists were not able to grow food and could not adjust to colder conditions - died out.

Question 15

Identify the possible causes of the Little Ice Age?

Answer 15

Orbital forcing due to cycles of Earth’s orbit - long term cooling period.
Low sunspot activity reduced solar output.
Volcanic activity blocks insolation.
Slowing down of ocean conveyor belt (Gulf Stream).
Global temp cooling due to increase in reforestation (increasing the storage of CO2).

Question 16

What is the Maunder Minimum and what was its effect on Europe?

Answer 16

1645-1715
Period of low sunspot activity
Coldest period of the Little Ice Age

Question 17

How did the Europeans adapt to the conditions of the Little Ice Age?

Answer 17

Changed from the three-field farming system to modern farming using enclosures and the use of technology.
Global temperature cooling due to reforestation increases the storage of CO₂.

Question 18

Define the Anthropocene.

Answer 18

Extent to which human activities are enhancing climate change
Increased rate of animal and plant extinctions since the spread of farming (8000 years ago).

Question 19

Why is a hunter-gatherer existence not part of the Anthropocene.

Answer 19

Live as part of their ecosystems.
Devise tools to increase their effectiveness.
Restricted by the amount of plant and animal food sources available.

Question 20

Why is farming part of the Anthropoene?

Answer 20

Clear natural landscapes.
Use techniques to intensify food production, sometimes using non-indigenous plant and animal species.
Potential for environmental destruction is greater.

Question 21

Why did the Industrial Revolution rapidly increase the human footprint on the Ecosphere?

Answer 21

Commenced with a massive increase in burning of fossil fuels rapidly increasing CO₂ levels in the atmosphere.
Mechanised and intensified farming.

Question 22

Why is CO₂ a more dangerous greenhouse gas when its ability to absorb heat is much lower than other greenhouse gases?

Answer 22

CO₂ is released in comparatively higher amounts compared to the other greenhouse gasses.

Question 23

Define radiative forcing.

Answer 23

The warming (or cooling) effect produced by greenhouse gases in the atmosphere.

Question 24

Give examples of greenhouse gasses.

Answer 24

CO₂
Methane
Halocarbons
Nitrous Oxide

Question 25

Define negative radiative forcing.

Answer 25

The cooling trend of aerosols in the atmosphere

Question 26

What factors produce negative radiative forcing and from what sources are they produced?

Answer 26

Occurs naturally from Sulphur in volcanic eruptions or from fossil fuel burning.
Produces Sulphuric acid in the stratosphere.
Consumer and industrial pollutants can also contribute aerosols.

Question 27

List the human activities that impact on the enhanced greenhouse effect in order of their contribution.

Answer 27

Power stations
Industrial processes
Transportation
Agriculture
Fossil fuel retrieval processing and distribution
Residential and commercial sources
Land use and biomass
Waste disposal and treatment

Question 28

Explain how ruminant animals contribute to increased greenhouse emissions.

Answer 28

Accounts for 9% of CO₂, 65% of nitrous oxide and 37% of methane.
Use enteric fermentation as part of their digestion (emitting methane).
Cause soil erosion, water pollution, eutrophication and coral reef degradation.

Question 29

List and briefly describe the ways in which agriculture (crop cultivation) contribute to the enhanced greenhouse effect.

Answer 29

Deforestation
Increases CO₂ (2% from 1999-2004)
Increases albedo (causes warming and cooling trends
Affects carbon absorption
Crops use less CO₂ than native plants
Reduces CO₂ sink of native plants
Burning biomass directly releases CO₂ into the atmosphere
Wet rice paddies release methane through the decomposition of plants
High use of fossil fuel in high yield mechanised agriculture

Question 30

Define Urban Heat Island.

Answer 30

Caused by the increased temperatures of urban areas compared to their surroundings (up to 10ºC).

Question 31

What aspects of urban areas contribute to the Urban Heat Island?

Answer 31

Concrete, bitumen and low levels of vegetation decrease a city’s albedo and increase the absorption of insolation.
Tends to be retained at night.

Question 32

What is the possible rise in temp over the next century?

Answer 32

Between 1.1° and 6.4°C

Question 33

What effect with the possible rise in temp have on Australia?

Answer 33

Temp rose between 0.2° and 1°C from 1970 to 2004

Temps could be expected to rise by more than 1°C

Question 34

Define albedo.

Answer 34

The degree to which the Earth’s surface reflects solar radiation ranging from 0 (no reflection) to 1 (maximum reflection).

Question 35

How do different surfaces vary in albedo?

Answer 35

Forests = 0.06-0.15
Deserts = 0.28 
Icecaps = 0.85

Question 36

How can changes to the Earth’s land cover affect its albedo?

Answer 36

Changes in land cover affect the heat budget and result in changes to global temperatures.
Deforestation and agriculture create bare soil, increasing albedo.
Loss of vegetation contributes to global warming.

Question 37

List some of the potential impacts of climate change on water supplies.

Answer 37

Increased supplies in the tropics and high latitudes.

Decreased supplies in the mid-latitudes.

Question 38

List some of the potential impacts of climate change on ecosystems.

Answer 38

At least 30% increase in extinctions, particularly those associated with coral reefs.

Question 39

List some of the potential impacts of climate change on food supplies.

Answer 39

Localised negative impacts.

Cereal will decline at lower latitudes.

Question 40

List some of the potential impacts of climate change on health.

Answer 40

Increased malnutrition and infectious diseases.
Deaths from heatwaves, floods and droughts.
Areal expansion of tropical diseases.

Question 41

List the impacts of climate change on coastal areas.

Answer 41

Severe storms threatening 100 million people who live within one metre of sea level and 25% of people living within 30 metres.
Water and sanitation systems placed under threat.
Increased estuarine development along rivers.
Sea water invasion of groundwater.
Increased use of defensive barriers for storm surges.

Question 42

Which areas of the world will suffer the biggest declines in freshwater supplies?

Answer 42

Central USA and California
Amazonia
Western Europe and European Russia
Middle East
Southern Africa
Western Sahara

Question 43

Define refugee species.

Answer 43

80% of plants and animals which have shifted their ranges closer to the poles.

Question 44

Identify the temperature difference between the city centre and the surrounding rural area.

Answer 44

1° to 3°C

Question 45

How does an urban landscape affect the carbon cycle?

Answer 45

Secondary industry, power production and transport.

Major producers of CO₂.

Question 46

Outline the ways in which climate variability can affect agricultural production in terms of livestock.

Answer 46

Increases heat stress.
Creates conditions for more widespread disease (sleeping sickness).
Reduces pastoral and stocking ratios.
Reduce water supply through rainfall.

Question 47

Outline the ways in which climate variability can affect agricultural production in terms of cropping.

Answer 47

Increases rainfall variability.
Causes changes to pests and fungal diseases.
Reduces soil moisture.
Increase extreme weather.
Improves growing seasons in cool temperate and sub-polar regions.

Question 48

List the different ways in which agriculture may need to adapt to changes in local climatic conditions.

Answer 48

Selective breeding of livestock and crop varieties.
Use modified pastures or alternative crops.
Develop new pest management strategies.
Introduce dietary supplements and supplementary feeding.
Increase water storage and water saving.
Diversify farming practices.
Shift to better regions.

Question 49

How will people living in cities have to adapt to climate change?

Answer 49

Construction of levees, sea walls and barriers.
Apply water-saving methods.
Use desalination plants.

Question 50

Define ocean acidification.

Answer 50

The increase of CO₂ storage in ocean water increasing the carbonic acidity of the water.

Question 51

Describe the problem of ocean acidification.

Answer 51

Acid reacts with carbonate ions to form bicarbonate. Reduces number of carbonate ions used by corals and shell fish- create carbonate shells.
Shells become thinner and more fragile.
More acid in the water dissolves calcium carbonate reducing the ocean’s ability to absorb more CO₂.
Changes the populations of microbial organisms, the basis of marine food chains.

Question 52

What would be the Earth’s temperature without the atmosphere?

Answer 52

-18°C

Question 53

What is the average temperature of the Earth due to the atmosphere?

Answer 53

15°C

Question 54

Describe the relationship between insolation and the warming of the atmosphere.

Answer 54

Short-wave insolation is absorbed by the Earth’s surface (land and water) and is re-radiated as longwave terrestrial radiation which heats the atmosphere.

Question 55

How does CO₂ absorb heat?

Answer 55

Dipole movements (vibrations of CO₂ molecules) capture infra-red radiation.

Question 56

List and describe the methods of achieving stability.

Answer 56

Reduce our use of fossil fuels and change to alternate sources
Greater efficiency with present sources, e.g., gas instead of coal.
Stop clearing forests and plant more trees.
Reduction of labour-saving devices.
Financial incentives to make changes.
Establishing international protocols such a Kyoto
Carbon tax
Carbon trading
CO₂ sequestration
Carbon offsets

Question 57

List examples of anthromes.

Answer 57

Urban (towns and cities) settlements
Rural (village) settlement 
Grazing properties
Cropland
Mining
Managed forests
National parks

Question 58

Examples of things that provide evidence for climate change.

Answer 58

Ice cores
Tree rings
Lake and ocean sediments
Fossil pollen
Corals
Temperature records
Ocean temperatures
Sea levels
Cryosphere

Question 59

Describe how tree rings (dendrochronology) provide evidence for climate change.

Answer 59

Patterns in tree-ring widths, density, and composition directly reflect variations in climate.
In temperate regions where there is a distinct growing season, trees generally produce one ring a year, recording the climate conditions each year.

Question 60

Describe how ice cores provide evidence for climate change.

Answer 60

Bubbles trapped within the ice capture the gas concentration of the atmosphere.

Question 61

Describe how lake and ocean sediments provide evidence for climate change.

Answer 61

Consist of biological and other materials that washed in from nearby land or that were produced in the lake/ocean.
Preserved as tiny fossils in the sediments (foraminifera) - used to infer past climate.

Question 62

Describe how fossil pollen (palynology) provides evidence for climate change.

Answer 62

Has unique shape depending on what plant it comes from.

Allows scientists to make inferences about past climates.

Question 63

Describe how corals provide evidence for climate change.

Answer 63

Coral skeleton density varies with changes in water temperature, light, and nutrient conditions.
This produces growth rings.