Depth Study One - Unit Review Booklet

Front 1

what is the Spatial distribution of precipitation and temperature patterns reflect on?

Back 1

Temperature and precipitation spatial distribution patterns reflect the way that the heat budget, hydrological cycle, carbon cycle and atmospheric circulation operate and interact.

Front 2

what is the Spatialdistribution of Temperature - January in NH

Back 2

In January it is winter in theNorthern Hemisphere. The lowest temperature occur over the northern continentswith the lowest temperature being across Siberia and Canada. Short days pluslong nights combined with a large landmass push the temperature well below zerodegrees Celsius across that area. It is that time of the year that the heatbudget is at its greatest deficit. Heat loss (terrestrial radiation) generallyexceeds insolation (incoming solar radiation). The temperature variationbetween eastern and western coastlines of Eurasia and North America is duemainly to effects of ocean currents. The Gulf Stream current carries warm wateracross the Atlantic from Central America to Western Europe. The prevailingWesterly winds are warmed by the Gulf Stream and this raises wintertemperatures in this region. Eastern coastal areas, on the other hand, haveprevailing winds from cold continental interiors and are generally colder thancorresponding latitudes.

Front 3

what is the Spatial distribution of Temperature - January in SH

Back 3

January is summer in the SouthernHemisphere. Long days and short nights make this time of heat surplus, as heatenergy builds up in the atmosphere. The warmest areas are the landmasses ofSouth America, Southern Africa and Australia. Australia’s rectangular shapemakes it susceptible to periods of high temperature when high pressure cellssit over the continent and moves hot tropical air from the north of thecontinent to the south. In general, summer temperatures for Southern Hemisphereare not as high as the Northern Hemisphere summer averages. This is becausethere is less land and more oceans in the south.

Front 4

what is the Spatial distribution of Temperature - july NH

Back 4

In July, Norther continents arestrongly heated. The hottest temperatures are the desert areas of the Sahara,Arabia, North West India and California with average temperatures in excess of30 degrees. Whilst equatorial regions receive the most solar radiation, theyare somewhat cooler than the deserts of the subtropical areas, sinceconsiderable energy is consumed in evaporating the abundant moisture thatprecipitates there and cloud cover reduces insolation.

Front 5

what is the Spatial distribution of Temperature - july SH

Back 5

Winter in the southern hemisphereoccurs during July. Once again average temperatures are moderated by the higherproportion of ocean to land. Comparisons of winter temperatures in bothhemispheres illustrate this difference.

Front 6

What is the spacial distribution of precipitation?

Back 6

Annually, an average of littleover one metre of precipitation falls across the entire surface of the worldregionally, there are extremes, ranging from places that do not receive anysignificant rainfall for years on end. (Arica in Chile 0.8mm) to places wereannual totals exceed 11 metres (Mt Waialeale in Hawaii 11,680mm). The highestrainfall occurs near the Equator. Here the air is rising, and being warm, iscapable of storing considerable amounts of water vapour. Most of the rainfallin the tropical belt is convectional, with prolonged heavy showers and frequentthunder storms. Towards the Poles, precipitation is low because the air is toocold to contain much water vapour.

The subtropical high pressure beltare regions of very low rainfall, due to stable atmospheric conditionsassociated with descending air. The northern temperate mid latitudes havemoderate rainfall, much of it frontal in nature, which declines towards theinteriors of North America and Asia.

Precipitation patterns shift Northand South with the changing seasons and the movement of the Thermal Equator.This is particularly significant in the tropical regions where monsoons bringheavy summer rain. Other regions that receive this seasonal variation includethe mid-latitude west coast regions where winter polar fronts bring rain andsnow followed by a summer dry season.

Front 7

explain what the heat budget refers to

Back 7

The heatbudget refers to the balance between the input of heat energy reaching theearth as short-wave radiation and output f heat energy emitted back into spaceas long-wave radiation.

Front 8

explain the operation of the heat budget in steps

Back 8

• As theshort wave insolation passes through the atmosphere some of it is reflectedback into space by clouds and particulate matter. Some of it is reflected fromlight coloured surfaces on the earth (ice) and is referred to as albedo.
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• Approximately19-20% of this insolation is absorbed by clouds and particles like ozonemolecules. This leaves about 50-51% of the short wave energy actually beingabsorbed by the earth’s surface where the solid earth changes this radiantenergy to heat energy and becomes warm. This then leads to a warming of thelower atmosphere through the process of conduction, convection, radiation andevaporation. Withconduction the atmosphere is heated by directed contact with the earth.
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• Withconvection the heated air rises and expands allowing cooler air to rise to comeinto contact with the source of heat. Heat leaves the atmosphere throughlong-wave radiation but it does not escape immediately as it is absorbed by gasesin the atmosphere such as water vapour, carbon dioxide and methane.
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• This isresponsible for keeping the atmosphere warmer during the night and is referred toas the natural greenhouse effect. Even though it holds energy for a length oftime it continually radiates the energy back into space and there is a balancebetween incoming and outgoing energy so as to maintain the earth’s temperatureat a relatively constant level.
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• If thereare imbalances in the heat budget then significant changes will be made to theearth’s climate. These can be produced through natural processes (e.g. orbitalvariation, solar output, albedo changes) or by human activity through changesto the composition of the atmosphere.
  

Front 9

what does the hydrological cycle refer to?

Back 9

The hydrologicalcycle refers to the continuous movement of water through the earth’senvironment in the form of water vapour, water, snow and ice. It is driven byenergy of the sun as heat is needed for the initial process of evaporation andtranspiration.

Front 10

explain the operation of the hydrological cycle in steps

Back 10

1. The heatneeded for evaporation is transferred to water molecules as kinetic energy. Theresult in water changing from a liquid to a gas (water vapour) while energyrequired for this change is carried into the atmosphere as latent heat.
2. The amountof water vapour that the atmosphere can hold is dependent on the temperature ofthe air and is expressed as a percentage referred to as relative humidity.Further moisture enters the air through a loss of water from the stomata ofplants and is referred to as transpiration.
3. When airbecomes 100% saturated with water dewpoint is reached resulting in the processof condensation whereby water returns to a liquid seen as cloud, fog or dew.
4. Advectioncurrents are then responsible for moving this water from one location toanother.
5. Someprecipitation will be evaporated but most will likely fall to the earth’ssurface where it may be infiltrated into the soil where it continues downwardtowards a zone of saturation. Some water will run off as a result of slope, poorpermeability of the soil or saturation of the ground. This discharge oftenfinds its way into streams and other water bodies.
6. Theevaporation of these water bodies continues in a cyclical nature of thisnatural system. Water can be locked up for long periods of time as ice sheetsor as ground water.
7. Theearth’s climate are heavily influenced by the hydrological cycle as the amountsof precipitation in the different areas continue to change. Since heat plays amajor role in the initiation of the cycle there is a close relationshipevident.
   

Front 11

explain the operation of the carbon cycle in steps

Back 11

1. Carboncirculates through the earth’s environment as a gas in the atmosphere, in rocks(e.g. calcium carbonate) and fossil fuels (e.g. coal) in the lithosphere, indecomposing vegetative matter in the biosphere and in the world’s oceans in thehydrosphere. These act as carbon sinks for differing periods of time.
2. Anincrease carbon levels in the atmosphere can lead to warming as it acts to traplong-wave heat energy thus impacting on local climates.
3. Carbon canbe sequestered from the atmosphere by green plants through the process ofphotosynthesis. Forests and woodlands are effective in keeping carbon levelsdown but deforestation acts to reduce the lands capacity to remove atmosphericcarbon.
4. Carbon canenter the atmosphere through volcanic activity, through bushfires and throughanthropogenic means such as the burning of fossil fuels like natural gas, coaland petroleum. Decaying plant and animal matter will also release increasedamounts of carbon dioxide into the atmosphere.
5. Carbon hasthe ability to be locked away for significant lengths of time in vegetation, asfossil fuels or in rocks. Some dissolved organic carbon accumulates with theremnants of marine organisms and becomes deposited on the sea floor to end upas sedimentary rock (e.g. limestone).
6. The carbonexchange between the atmosphere and the oceans results in some carbon dioxideentering the water and leaving solution behind. This dissolved carbon dioxideis then taken in by marine plants and animals (limpets and whelks). Differentlevels of operation can also be observed in the world’s oceans. More carbon isremoved from the atmosphere in cold waters but in warm waters there is agreater release of carbon dioxide. Where there is an upwelling of oceancurrents further carbon will be given off.
7. A naturalbalance needs to be obtained between reservoirs of carbon to provide theequilibrium needed for minimal impact of climate cycles, Human activities suchas over-clearing and the combustion of fossil fuels are said to have disruptedthese cycles leading to evidence of global warming.
   

Front 12

explain the operation of the atmopsheric circulation in steps

Back 12

1. Unevenheating is responsible for variations in the air pressure across the surface ofthe earth and this is responsible for driving the earth’s climates. Warm airexpands and takes up larger volume producing lower density and lower airpressure whereas cooler air contracts and takes up a much smaller volumeproducing high density and therefore higher air pressure.
2. Theconstant movement of air from higher to lower air pressure produces winds andcurrents and the transfer of heat and water across the world.
3. Due to theconcentration of the sun’s rays in the tropics lower air pressure and greaterevaporation of moisture takes place. Rising tropical air moves upwards andoutwards and cools. If finally descends into sub-tropical high pressure cell athigher latitudes.
4. Surfaceair rushes in to replace rising air creating wind that seem to follow a curvedpath as a result of the rotation of the earth referred to as the CoriolisEffect . As these winds cross large expanses of warm water it is responsiblefor heavy onshore rainfall.
5. There isseasonal movement of the equatorial low pressure cells as a result of changes tothe sun’s overhead position during orbit. The heat equator therefore migratesbetween the northern and southern hemisphere over the year forcing the otherpressure to migrate as well, affecting seasonal patterns of dominant winds.
6. Higher airpressure exists over the poles due to colder conditions from less concentrationof the sun’s rays. The flow of air outwards from these cells can create verystrong winds on the surface. Air moves towards the sub-polar low pressure systemsand pushes under warmer sub-tropic air creating cold fronts. This phenomenonbrings winter rains to southern Australia.
   

Front 13

what are the main interactions between the Heat Budget and hydrological cycle:

Back 13

· Cause evaporation, transpiration and condensation

· Influence movement of the ocean currents· Produce convectionalmovement of air and advection of water vapour

Front 14

what are the main interactions between the The hydrological cycleinteracts with the heat budget.

Back 14

· Transfer heat (latent energy) into the atmosphere by evaporation and condensation · Reflect light (albedo) from cloud and ice surfaces

· Transfer energy from the Equator to the poles via ocean currents.

Front 15

what are the main interactions between the Heat budget andatmospheric circulation.·

Back 15

Produce regions of low pressure which then causes convectional air currents.

· Produce different zones of low and high pressure due to differential heating of land and sea

· Affect the intensity of low pressure produced by heating, which results in varying pressure gradients and wind speeds.

· Cause seasonal variations in the location of the global air pressurfe belts due to the tilt of the Earth’s axis and north-south shift of the Thermal Equator.

Front 16

what are the main interactions between the Atmospheric circulationinteracts with the heat budget to:

Back 16

· Transfer energy away from the Equator towards the Poles viaHadley and Polar cells.

· Transfers energy from the ground into the air via convection

· Retain heat in theatmosphere through the presence of greenhouse gases including CO2, methane andwater vapour.

Front 17

The hydrological cycleinteracts with atmospheric circulation to:

Back 17

· Produce regions of high and low pressure· Transfer energy into the air through evapotranspiration,which then drives atmospheric circulation.

· Remove energy from theatmosphere by condensation and precipitation in low pressure systems.

Front 18

1. Atmospheric circulationinteracts with the hydrological cycle to:

Back 18

· Move water from one region to another via advection

· Produce upward moving unstable air masses where atmosphericcooling results in condensation and precipitation.

· Produce sinking, stableair masses where relative humidity decreases any potential evaporation rates.

Front 19

what are the main interactions between the 1. Atmospheric circulationand the heat budget interacts with the carbon cycle.

Back 19

· Influence the amount of atmospheric CO2 and the greenhouseeffect.

· Remove CO2 from the atmosphere via exchanges with thebiosphere, soils and oceans.· Form of a climate change feedback loop where risingtemperatures due to the enhanced greenhouse effect then increase the amount ofCO2 being released from soils to the oceans.

Front 20

natural causes of climate change - volcanic activity

Back 20

Increasedvolcanic activity impacts directly on the atmosphere and heat budget. Duringperiods of increased explosive volcanic activity, large amounts of fine ash and gases such as watervapour and Sulphur dioxide are ejected into the atmosphere. Theseaerosols can reflect sunlight and reduce insolation by as much as 10 percent.The major eruptions in both the Krakatoa and Mt Pinatubo, reduced by about 2 degrees in the year after the event. Volcanic activity can thereforecool the planet.

Non explosive volcanic activity: This type of volcanic activity can enhanceglobal warming by adding CO2 to the atmosphere which traps longwave radiationand helps keep the atmosphere warm.

Front 21

natural causes of climate change - changes in albedo

Back 21

Regionalchanges in albedo can alter weather patterns there. Clearing of forests acrosslarge areas of the middle to high latitudes in the Northern Hemisphere hassignificantly altered the albedo in these regions. Snow cover on trees wouldreflect about half the sunlight falling on it, whereas snow-covered open groundreflects about 2/3 thirds.

The effectis to cool those regions. This can however be offset by increase in temperatureassociated with the movement of warmer waters and air off the tropics.

heat island effect

Front 22

natural causes of climate change - Variations in solar output

Back 22

The amountof energy that the sun emits is affected by variations on its surface thatproduces sunspots and is said to experience an 11 year sunspot cycle.

Solarmaximum conditions with more sunspots seem to slightly influence the Earth’srainfall patterns favouring rainfall north of the Equator (South Asian monsoon)while decreasing rainfall near the equator

Increasedsolar UV can warm regions of the world.

Impactstend to more regional than global.

One longterm correlation between solar activity and climate change was observed withthe Maunder minimum, a period of little to no sunspot activity that wasassociated with a significant cooler period of colder weather in Europe.

Front 23

anthropogenic causes of climate change - Fossilfuel use:

Back 23

There are anumber of ways in which fossil fuel use affects climate. The widespread burningof coal has radically added large amounts of CO2 in the atmosphere. The changesin CO2 has increased from 280ppm in pre industrial times to 380ppm in 2005.This change in anthropogenic greenhouses has enhanced the natural greenhouseeffect. As such the earth’s average temperature has increased 1 degree since1900.

Enhanced greenhouse effect – globalwarming. This interference to the natural systems has created a new set ofinteractions that is resulting on significant changes to rainfall andtemperature patterns on the globe.

Front 24

anthropogenic causes of climate change -deforestaion

Back 24

• : Deforestation for agricultural or urban land sue purposes,has been a major contributor to increased carbon dioxide levels. Forests are amajor carbon sink and their removal results in a net increase in CO2 levels inthe atmosphere. The United Nations Food Organisation (FAO) estimates thatforests are disappearing at the rate of 13 million hectares per year.
• Up to 90% of West Africa’s coastalrainforests have disappeared since 1900 in countries like Liberia, Ghana andGuinea. Central America has lost 40% of all its rainforest in the last 40 yearsin countries like Honduras and Panama.
• South Asia has lost over 85% of itsrainforest to agricultural practices. Large areas of Indonesia (also Brazil InSouth America) are being replaced by a single crop Palm Oil.
• It is estimated that tropical deforestationreleases 1.5 billion tonnes of carbon each year into the atmosphere. Tropicaldeforestation is responsible for between 6 – 17% of worldgreenhouse emissions.
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• The interaction and the heat budgetand the atmosphere will result in changes to air pressure and subsequent windpatterns. Atmospheric circulation contributes to the global transfer of heatand water and with modifications to these global patterns there will be changeson local temperatures, changes in rates of evaporation and the distribution ofrainfall on a large scale.
• The general imbalance of the heatbudget has major ramifications. Warmer temperatures will result in the presenceof less ice and snow which will reduce albedo leading to further heating.Warming temperatures will also contribute to an increase in extreme weatherevents such as cyclones and floods.
  

Front 25

anthropogenic causes of climate change - agriculture

Back 25

• Much of the land is being cleared forpastoralism due to increased world demand for meat and dairy products. Thelivestock alone is responsible for 9% of all carbon dioxide produced from humanrelated activities, 65% of nitrous oxide emission through their manure and 37%of all methane through their digestive systems.
• It is estimated that 30% of theearth’s surface is now devoted to livestock rearing, or 70% of all arable land.With increased demand it is expected that more land will be cleared (e.g.Brazil) and be replaced with pastoral activities (e.g. cattle, sheep).
• Wet rice production has been a majorcontributor to the production of methane. Methane is 20 times more potent agreenhouse gas than CO2. Methane arises from fermentation of organic mattercontained on the soil.China, India, Indonesia, Bangladesh,Vietnam and Thailand produce 30 million tonnes of rice annually. The largestpopulations of China and India are said to consume more than 200 million tonnesof rice each year.
• Increased use of machinery forclearing, cultivation, harvesting and distribution has led to furthergreenhouse gas emissions. The use of fertilisers can contributeto large amounts of nitrous oxide to the atmosphere.
• Over cultivation has led todesertification.
  

• Agricultural practices has had a majorimpact on other natural systems such as the hydrological cycle. Deforestationhas a major effect on rainfall patterns due to a reduced canopy interception,changes to infiltration rates, increase in surface runoff and the reduction ofmoisture being cycled back into the atmosphere. This leads to further problemsof erosion, flooding and landslides.
• Over stocking of livestock can lead to soilcompaction and waterlogging and changes to natural watercourses. Over tillagecan reduce soil moisture content and rising water tables increasing salinity.
  

Front 26

what is one types of evidence fro climate change through geological time?

Back 26

• Climate change refers to the changesin global temperatures and precipitation over an extended period of time. Thistime frame can range from millions of years to decades and can be studied on alocal, regional or global scale. This concept refers to both warming periodsand cooling periods.
• Evidence for climate change can bestudied through geological time through the use of proxy (indirect) data. These include the study of ice cores, thestudy of tree rings (dendrochronology), through coral bleaching and sea levelchanges.
• Glacial ice contains dust and airbubbles with isotopes of oxygen that can be used to interpret the climate atthe time the snow fell and formed ice. The thick layer of ice that accumulatedover thousands of years provide a record of the past global climate andscientists drill deep into icecaps to collect ice cores in order to obtain thishistorical data.
• Also as ice forms from the annual buildup from layers of snow it contains remnant dust, ash, pollen and bubbles ofatmospheric gases. As snow continues toaccumulate, the snow beneath is compressed until surface pores are closed offand traps the particles and bubbles within, providing evidence of past climaticpatterns. Some ice cores can be used to reconstruct an uninterrupted climaterecord and one ice core from Vostok on Antarctica has provided us withinformation for the last 420,000 years an clearly reveals four past glacialcycles.
  

Front 27

· one major type ofevidence for climate change in recent human history

Back 27

• Evidence for climate change can alsobe obtained from recent human history through data collection frommeteorological records, documentation of extreme weather events, data fromweather satellites, and weather balloons, measurements in glacial extent andfrom observable changes to sea levels.
• World weather records began in 1923and produces a large volume of monthly data about temperature, precipitationand air pressure from hundreds of stations around the world. From these recordswe have observed changes to local and regional patterns (e.g. decline in annualprecipitation in the south-west of Western Australia) and a significantincrease in wet season precipitation
  

Front 28

what is the interrelationshipbetween land cover change and climate, including changes to surfacereflectivity (albedo) and the process of natural carbon sequestration

deforestation - including changes to surface, impact on climate and regional/global examples

Back 28

Changes to surfaces

• The clearing of forests across large areas of the middle to higher latitudes in the Northern Hemisphere has significantly altered the albedo in these regions. Impact on climate
• The albedo has increased. This is because snow on the once present trees used to reflect only about half of the sunlight falling on it; whereas snow covered open ground reflects about two thirds. This change has the potential to create a negative feedback loop and there a cooling trend.

Regional/Global examples

• High latitudes in the northern hemisphere.
  

Front 29

what is the interrelationship between land cover change and climate, including changes to surface reflectivity (albedo) and the process of natural carbon sequestration

urban development - including changes to surface, impact on climate and regional/global examples

Back 29

heat island effect - urbanisation of the landscape, changing from natural biulding infratsurcture - dark infraturcture such as roads, buildings

impact on climate - decrease in albedo, heat is absorbed rather than reflected making those areas a lot warmer. any urban landscape such as sydney, any mega city, more likely in developed countries

Front 30

the effects ofclimate change on land cover in natural and anthropogenic biomes (vegetation,ice sheets, glaciers, coastal systems and coral reefs, agriculture, urbansettlements and industry) - decrease in precipitation and increase in temperature - vegetation

Back 30

VegetationAs temperatures increase in the higherlatitudes of northern hemisphere there will be a redistribution of forests asconiferous forests move further north and invade former regions of tundra. Somepermafrost will thaw releasing greenhouse gases leading to further warming andencouraging even more plant growth.

Changes in snowlines will result indifferences in vegetation patterns and would result in major changes tobiodiversity as high altitude habitats come under competition for space.

Front 31

the effects of climate change on land cover in natural and anthropogenic biomes (vegetation, ice sheets, glaciers, coastal systems and coral reefs, agriculture, urban settlements and industry) - decrease in precipitation and increase in temperature - ice sheets

Back 31

The massive ice sheets of Antarcticaare showing signs of climate induced change. The Larson ice shelf on theAntarctic peninsula has undergone a significant reduction in recent years. Itis currently 40% of its size prior to the 1990’s. There is also increasingtemperatures, especially in Western Antarctica and extensive areas of melt lakesforming on the surface of the Antarctic ice sheet, which is seen as anindicator of ongoing climate induced change.

example antarctica

Front 32

the effects of climate change on land cover in natural and anthropogenic biomes (vegetation, ice sheets, glaciers, coastal systems and coral reefs, agriculture, urban settlements and industry) - decrease in precipitation and increase in temperature - glaciers

Back 32

A reduction in glacial ice as a resultin warmer temperatures in these areas (e.g. Greenland) will see a decline in albedoas more of the sun’s rays are absorbed also contributing to further warming.

Also as glaciers melt there is anacceleration in the process. Running water melts ice at the base and at thetop. It also penetrates the ice forming crevices. Together these increase processesspeed up glacial melt.

example greenland

Front 33

the effects of climate change on land cover in natural and anthropogenic biomes (vegetation, ice sheets, glaciers, coastal systems and coral reefs, agriculture, urban settlements and industry) - decrease in precipitation and increase in temperature - coastal systems

Back 33

Rising sea levels will bringsignificant change to Australia’s coastal zone in the coming decades. Some ofthe impacts will be:

· beach loss

· salinization of wetlands

· tidal flat communities

· salt marshes

· inundation of low lyingareas and reefs.

Front 34

the effects of climate change on land cover in natural and anthropogenic biomes (vegetation, ice sheets, glaciers, coastal systems and coral reefs, agriculture, urban settlements and industry) - decrease in precipitation and increase in temperature - coral reefs

Back 34

• Oceans are becoming more acidicbecause of an increasing amount of atmospheric carbon dioxide that is beingabsorbed by surface waters. This forms carbonic acid which ultimately effectsthe growth of corals as it reduces the number of carbonate ions available tobuild their skeletons.
• Coral bleaching can also occur due torising sea surface temperatures.
• Without reefs, which can act as acoastal buffer, mainland and island shores will be subject to higer energy waveconditions. This could lead to loss of sandy beaches. This concern is noted forthe Ningaloo Reef in Western Australia.
  
• example Great Barrier ReefAustralia

Front 35

the projectedimpacts of global climate change - temperature - characteristics and examples

Back 35

characteristics - The temperature couldrise between one and ve degrees Celsius by 2100 but the predicted mean globalsurface temperature is expected to rise at 2.5 degrees Celsius by the end ofthe century. The part of the world that is expected to be the most affected bythe temperature change is the middle to high latitudes in the NorthernHemisphere although the north-west of Australia is also expected to feel thetemperature rise.

examples - northern hemisphere and northern Australia

Front 36

the projected impacts of global climate change - precipitation - characteristics and examples

Back 36

Precipitationchanges are not as certain as the temperature changes but they are expected toshow some signs of change. Some places may receive less rainfall, some mayreceive more and some may have little or no change. A fall inprecipitation means less fresh water for the future generations.

examples - Australiais expected to have an overall decrease in rainfall across the country withSouth Australia and Western Australia both being the worst hit, possibly losingover 20% of annual rainfall.Otherareas expected to receive less rainfall include: Portugal and Greece, Morocco,South Africa, and Mexico city.

Regionsthat are expected to receive more rainfall include: Ethiopia, Uganda, Peru,Ecuador, and Indonesia.

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the projected impacts of global climate change - climate boundary shift - characteristics and examples

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Climate boundary shiftsare caused by a change in the ocean temperature, global atmospheric circulationand the upper atmosphere Jet Streams. This means that our weather patterns andclimate zones are shifting across the world. Principle climatic zones appear tobe shifting Poleward.

For example climatessuch as the Mediterranean climate of South Western Australia will be replacedby semi-arid conditions.

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the projected impacts of global climate change - extreme weather events - characteristics and examples

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Extreme weatherevents are becoming a more common occurrence with the amount of severe storms,ooding, droughts, heat waves and violent tropical cyclones globally increasingat a high rate. Heat waves are a major concern as they are becoming a greaterrisk each year..

examples - Many temperaturerecords have been broken in Australia over the last 10 years and this trend isexpected to continue in the future. The average temperature has phenomenallyincreased from about the 1970s and has continued to rise since. According todata from NASA, last year was the thirty-seventh consecutive year ofabove-normal global temperature and since 1970, each decade has averaged 0.75degrees Celsius warmer than the preceding one

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the projected impacts of global climate change - environmental impacts - sea levels - characteristics and examples

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Theprojected sea level rise by 2100 is 40 to 80cm with the possibility of the risebeing even greater. This depends on the temperature of the water and theeffects of thermal expansion. There are major possibilities when it comes tothe rising of the sea level. If the Greenland ice sheet was to completely melt,that would add about 7 metres to the oceans height and in the unlikelyoccurrence of the Antarctic ice sheet to melt, the ocean level would rise bysome 60 metres. This would cause a huge problem as many millions of peoplearound the world live within 1 metre above sea level. Higher sea levels alongwith storm surges and high tides would ood large areas of land and potentiallycover low lying coastal island such as the Maldives and the Cook Islands.

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the projected impacts of global climate change - environmental impacts - ecosystems - characteristics and examples

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Ecosystemsof the world will be largely impacted depending on the biome they live incurrently. Many plants and animals will not be affected by the rise intemperature and lack of rainfall in the coming years but are still expected tohave some sort of change by 2100. Species living in the desert, rainforest,savanna and tropical biomes will have little or no change due to the fact thatthese plants and animals have already adapted to the high temperatures and lowrainfall. The Northern Hemisphere is expected to be the most impacted areaparticularly in the boreal and tundra biomes of the sub-Arctic region due tonaturally cold temperatures barely ever reaching above 12 degrees Celsius. A 2degree Celsius increase in the global temperature would result up to 30% ofplants and animals species while a 5 degree increase would cause extinction.The change in landforms can be caused by a rise in the sea level, anotherprojected impact from climate change. They will produce retreating coastlinesand areas are expected to become ooded and eroded by rising water levels.Around 1 centimetre rise in sea level reduces beach width by 30 centimetres.Changes in rainfall intensity will also impact many landforms causing excessiveerosion. Physical and chemical weathering processes are also linked to climateconditions with chemical weathering being more pronounced in hot, wet climates.The rise in temperature would cause chemical weathering to become more activeand therefore chip away at landforms.

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the projected impacts of global climate change - human impacts - agriculture- characteristics and examples

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Climatechange can have many impacts on agriculturearound the world. Seasonal rainfall reliability and intensity, temperatureranges and extremes and wind speeds can all affect future agriculturalproduction. The temperature has a great impact on the germination and maturingstage of a plant as being too hot or too cold can kill the plants and stop themfrom growing. For example, some fruits require cold, frosty weather due to thehigher temperatures fastening plant maturity causing less fruit to be producedas the growth stages would be shortened. This also affects vegetable growth andcrop yields in tropical countries. This image below shows the percentage ofagriculture expected to be impacted around the world with the NorthernHemisphere being the most affected. With increased temperatures in the NorthernHemisphere, grain production is expected to be able to occur further north thanthe currents limits but growth in the Southern Hemisphere is expected todecline with the movement of the biomes.

IPCCprojects the following changes in agriculture such as: - A decline in forestryand agriculture in Australia and New Zealand by 2030. - Worse conditions foragricultural production in Southern Europe due to climate change. - Moderateclimate change is initially expected to increase agriculture growth by 5 to 20%in North America. - Important agriculture regions are expected to become underthreat from rising sea levels in Asia. - Livestock productivity in SouthAmerica is projected to decline. There are many urban impacts on the world dueto climate change. Cities are very vulnerable to the effects of climate changebecause of the inability to relocate if a weather related issue is to arise.The need to meet future water demands, the need to construct building and developmedical services to protect again heat waves, and the need to plan for theeffects of rising sea levels on coastal settlements are all major potentialimpacts Australia has to deal with. An increase in capital expenditure will beneeded across the globe to provide alternate water supplies including producingnew desalination plants. More than 40% of the world’s large cities are suppliedby surface water reservoirs and could become vulnerable to shortages anddroughts by 2040. Extreme weather events are also a huge issue for coastalcities. Storms and ooding are expected to become more intense and morefrequent as the years go on. Sea walls, ood barriers and the building oflevees will need to be built around low lying coastal areas to protect againststorm surges and rising sea levels. This leaves poorer countries morevulnerable than developed nations.

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the projected impacts of global climate change - human impacts - health effects- characteristics and examples

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Health effects due toclimate change on people of the world are generally expected to be negative.The World Health Organisation has projected that between 2030 and 2050, climatechange could cause approximately 250,000 additional deaths per year frommalaria, diarrhoea, heat stress and malnutrition and that direct damage coststo health could be 2 to 4 billion dollars per year by 2030. In Australia theprojected health impacts will include direct and indirect effects. By 2100,heat related deaths and hospitalisations are expected to double when comparedwith no climate change. Those living in poorer countries are much morevulnerable to climate change health impacts with children being exposed to theeffects for longer periods of time. The elderly can also be severely affectedas they generally have pre-existing medical conditions. The governments areworking to plan for projected health issues that will develop as the climatechanges in the 21st Century.

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rate of climate change - temperature

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Majorworld organisations, including NOAA, NASA, IPCC, the CSIRO and the BOM allconclude that the earth climate system is warming that the climate trends overthe past century are very likely due to human activities. Most ofthe warming has occurred since the 1970’s, with the 20 warmest years havinghappened since 1981 and with all the 10 warmest years occurring the last 12years (up to 2014).

The IPCChas a number of scenarios ranging from small increases to large and potentiallycatastrophic temperature changes. Projects that compare at the end of the 21stcentury to last range from 0.9 to 4.0 degrees Celsius.

Thechanges will not be even across the planet. The greatest increase will likelybe in the Northern hemisphere regions including Arctic, across Canada, thenorthern regions of Europe and Asia as well as Western Antarctica. The effectof temperature changes will change the hydrological cycle, atmosphericcirculation and the carbon cycle via series of feedback loops.

InAustralia, the average temperature has already increased by 1 degree since1910, with most of the warming occurring since 1950. This warming has seenAustralia experience more warm weather and extreme heat and fewer coolextremes. There has also been an increase in extreme fire weather, and a longerfire season.

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rate of climate change - precipitation

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Globalprecipitation patterns are becoming less predictable. A warmer climate isincreasing the risks of both droughts and floods. This is due to the way thehydrological cycle, the heat budget and the atmosphere interact.

InAustralia there have been significant changes in the amount of precipitation,its distribution, predictability and intensity. Since 1950s there has been amajor change in the distribution of rainfall. The northwest of Australia hasseen a significant increase while most of the east coast and south west of thecontinent have seen a significant decline. In 2011, annual rainfall recordsbroke across areas of Northern Australia and much of QLD was flooded by acombination of heavy monsoon rainfall and impact of cyclone Yasi.