environment 2015

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Page 1: Environment 2015

EnvironmentalEnvironmentalConcernsConcerns

Page 2: Environment 2015

Human Impact on Greenhouse GasesHuman Impact on Greenhouse Gases

Page 3: Environment 2015

Global Warming - ReasonsGlobal Warming - Reasons Carbon dioxide gases released into Carbon dioxide gases released into

environmentenvironment Due to massive amounts of Due to massive amounts of non-renewable non-renewable

fossil fuelsfossil fuels being burned by humans, being burned by humans, including:including:• CoalCoal• OilOil• Natural gasNatural gas

Non-renewable resources - Non-renewable resources - cannot be created over again and cannot be created over again and our supply of them is limited; once our supply of them is limited; once they run out, the resource is gone they run out, the resource is gone forever.forever.

Page 4: Environment 2015

Global WarmingGlobal Warming Some naturally occurring contributors to Some naturally occurring contributors to

global warmingglobal warming: : volcanic eruptions & meteor volcanic eruptions & meteor impactsimpacts

Page 5: Environment 2015

Most Global Warming Impacts Most Global Warming Impacts caused by Climate Changecaused by Climate Change

Page 6: Environment 2015

ClimateClimate Climate is commonly defined as the Climate is commonly defined as the

weather (temperature and rainfall) weather (temperature and rainfall) averaged over a long period of timeaveraged over a long period of time

The climate The climate of a location of a location is affected by is affected by its latitude, its latitude, terrain, terrain, altitude, ice altitude, ice or snow or snow cover, as well cover, as well as nearby as nearby water bodies water bodies and their and their currents.currents.

Page 7: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Rising incidence of Rising incidence of violent stormsviolent storms

North American Hurricane Season 2005North American Hurricane Season 2005

Page 8: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Rising incidence of Rising incidence of heat wavesheat waves (Europe (Europe

2003)2003)

Page 9: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Above average temperatures Above average temperatures melting melting

glaciers and sea levels are risingglaciers and sea levels are rising as a as a resultresult

Page 10: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Rising Sea LevelsRising Sea Levels

Page 11: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Diseases are spreading more quickly and Diseases are spreading more quickly and

easily easily extending their ranges because of warmer extending their ranges because of warmer

temperaturestemperatures Many diseases, especially those in water, Many diseases, especially those in water,

reproduce more rapidly in warmer weatherreproduce more rapidly in warmer weather

Page 12: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming

Earlier arrival of springEarlier arrival of spring in some parts of in some parts of the world – the world – impacting global agricultural impacting global agricultural patternspatterns

Page 13: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming As As permafrost meltspermafrost melts, Arctic communities , Arctic communities

lose valuable shorelinelose valuable shoreline

Page 14: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming

Causes Causes polar bears to starvepolar bears to starve because because they cannot use the ice to hunt sealsthey cannot use the ice to hunt seals

Now on Now on endangered endangered species listspecies list

Page 15: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming

Canada’s Canada’s Arctic regions Arctic regions – – sea ice sea ice shrinkingshrinking Causes Causes

sinking sinking shorelines shorelines and death of and death of some Arctic some Arctic animalsanimals

Page 16: Environment 2015

Global Warming in CanadaGlobal Warming in Canada

Page 17: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming In BC – increasing water temperatures In BC – increasing water temperatures

have contributed to have contributed to salmon spawning salmon spawning numbers being 1/3 of what they were in numbers being 1/3 of what they were in 1990s1990s

Page 18: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming While warmer temperatures could While warmer temperatures could

lengthen Canada’s short growing season – lengthen Canada’s short growing season – also also higher risk of drought and forest fireshigher risk of drought and forest fires

Page 19: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming Warmer weather causes Warmer weather causes increasing increasing

numbers of forest fires and more droughts numbers of forest fires and more droughts in Canada’s prairie areasin Canada’s prairie areas

Page 20: Environment 2015

Effects / Results of Global WarmingEffects / Results of Global Warming

Canada’s oceansCanada’s oceans Increasing surface Increasing surface

water temperatures, water temperatures, fewer nutrients are fewer nutrients are brought to the surface brought to the surface by the movement of by the movement of colder water from deep colder water from deep in the oceanin the ocean

Nutrients support and Nutrients support and maintain zooplankton – maintain zooplankton – beginning of the food beginning of the food chain of sea lifechain of sea life

Page 21: Environment 2015

Kyoto Protocol - 1997Kyoto Protocol - 1997 Agreement among 180 Agreement among 180

industrialized nations to industrialized nations to reduce greenhouse gas reduce greenhouse gas emissionsemissions

Canada promised to Canada promised to reduce greenhouse gas reduce greenhouse gas emissions by 6% of the emissions by 6% of the 1990 level by 20121990 level by 2012

Countries not meeting Countries not meeting their reduction targets their reduction targets could buy credits from could buy credits from other countriesother countries

USA withdrew in 2001USA withdrew in 2001

Page 22: Environment 2015

Arguments against KyotoArguments against Kyoto Concerned that meeting Concerned that meeting

goals will involve high goals will involve high costs to businesses and costs to businesses and government and possible government and possible loss of jobsloss of jobs

Provincial governments Provincial governments must regulate polluting must regulate polluting industries despite the fact industries despite the fact that the federal that the federal government signed the government signed the agreement without agreement without consulting the provincesconsulting the provinces

Some argue not enough Some argue not enough evidence that global evidence that global warming to blame for warming to blame for climate changeclimate change

Page 23: Environment 2015
Page 24: Environment 2015

Kyoto & CanadaKyoto & Canada

2006 - Canada's 2006 - Canada's greenhouse gas greenhouse gas emissions were up emissions were up by 24% by 24%

far from the far from the government's government's commitment to meet commitment to meet a target 6% below a target 6% below the 1990 levelsthe 1990 levels

Page 25: Environment 2015

Kyoto & CanadaKyoto & Canada Election of a Conservative Election of a Conservative

government in 2006 brought government in 2006 brought about a reversal in Canada's about a reversal in Canada's climate change policyclimate change policy

2007 –2007 – Government Government announced plans to announced plans to introduce legislation that introduce legislation that would regulate industrial would regulate industrial pollutants as part of the pollutants as part of the Conservatives' proposed Conservatives' proposed Clean Air ActClean Air Act, to take effect , to take effect in January 2010. in January 2010.

said Canada will not attempt said Canada will not attempt to meet Kyoto's greenhouse to meet Kyoto's greenhouse gas targetsgas targets

Page 26: Environment 2015

Possible Solutions – Possible Solutions – Renewable Energy ResourcesRenewable Energy Resources

Sustainable Sustainable sources of sources of energy could energy could lessen lessen dependence on dependence on fossil fuels, such fossil fuels, such as:as: Wind TurbinesWind Turbines

http://www.youtube.com/watch?v=Hg9fiDUroo4

Page 27: Environment 2015

Wind PowerWind Power

Page 28: Environment 2015

Solutions - Solar Power PanelsSolutions - Solar Power Panels

http://www.youtube.com/watch?v=iG7FNcw7a5c&feature=related

http://www.youtube.com/watch?v=0hCggdtEU-M&feature=related

Page 29: Environment 2015

Solutions – Tidal PowerSolutions – Tidal Power

http://www.youtube.com/watch?v=qRUl1mJQHmc&feature=related

http://www.youtube.com/watch?v=F0mzrbfzUpM&feature=related

http://www.youtube.com/watch?v=VamSAbwgJKk&feature=related

http://www.youtube.com/watch?v=tSBACzRE3Gw&feature=related

Page 30: Environment 2015

Solutions – Ground Source EnergySolutions – Ground Source Energy

http://www.youtube.com/watch?v=kUvdNrOD4PY

http://www.youtube.com/watch?v=lD82e5RYfW8&feature=related

Page 31: Environment 2015

Solutions – BiofuelsSolutions – Biofuels Ethanol – some made from CornEthanol – some made from Corn

Page 32: Environment 2015

Ethanol – ConcernsEthanol – Concernso Ethanol – while reduces levels

of carbon monoxide and other toxic air pollutants, corn-based ethanol production is energy intensive, and in some instances uses nearly as much energy to produce (including the energy needed for farming and making fertilizers) than it supplies, although new technologies are improving the efficiency of production.

http://www.youtube.com/watch?v=j9QQcP_Y1IIhttp://www.youtube.com/watch?v=8R012X3tU6Y&feature=related

Page 33: Environment 2015

Biofuels – instead of gasolineBiofuels – instead of gasoline

http://www.youtube.com/watch?v=WRB5VQMb5RI

Page 34: Environment 2015

Geothermal EnergyGeothermal Energy

Heat from the ground harvestedHeat from the ground harvested

Page 35: Environment 2015

Alternatives to Alternatives to Reduce Reduce Fossil Fuel Use Fossil Fuel Use

Hydrogen or methanol fuelled power cells Hydrogen or methanol fuelled power cells for automobilesfor automobiles

Page 36: Environment 2015

Alternatives to Alternatives to ReduceReduce Fossil Fuel Use Fossil Fuel Use Reduce, re-use, recycleReduce, re-use, recycle

Page 37: Environment 2015

Alternatives to Alternatives to ReduceReduce Fossil Fuel Use Fossil Fuel Use

Carpool, use public transportation, ride Carpool, use public transportation, ride bicycle or walkbicycle or walk

Page 38: Environment 2015
Page 39: Environment 2015

Ozone DepletionOzone Depletion

Ozone layer – Ozone layer – region of the region of the atmosphere atmosphere containing containing relatively high relatively high concentrations of concentrations of ozone – approx ozone – approx 19-48km above 19-48km above the Earth’s surfacethe Earth’s surface

http://www.youtube.com/watch?v=SSycyCuQmUA&feature=related

Page 40: Environment 2015

Ozone DepletionOzone Depletion

Ozone is formed Ozone is formed by the action of by the action of solar ultraviolet solar ultraviolet light on oxygenlight on oxygen

It’s the only gas It’s the only gas able to block out able to block out the ultraviolet the ultraviolet rays from the sunrays from the sun

http://www.youtube.com/watch?v=e9fqpnkiUi0&feature=related

Page 41: Environment 2015

Ozone - DamageOzone - Damage Chlorofluorocarbons (CFCs)Chlorofluorocarbons (CFCs)

Have done 80% of the damage to the Ozone Have done 80% of the damage to the Ozone Layer (creating “holes”)Layer (creating “holes”)

Widely used in coolants for refrigerators and Widely used in coolants for refrigerators and air conditioners, solvents, and aerosol cansair conditioners, solvents, and aerosol cans

Page 42: Environment 2015

Results of Ozone DepletionResults of Ozone Depletion

Page 43: Environment 2015

Results of Ozone DepletionResults of Ozone Depletion

Higher incidences of skin cancerHigher incidences of skin cancer

Page 44: Environment 2015

Results of Ozone DepletionResults of Ozone Depletion

Reduction of microscopic marine life like Reduction of microscopic marine life like phytoplankton which will impact the food phytoplankton which will impact the food chainchain

Page 45: Environment 2015

Results of Ozone DepletionResults of Ozone Depletion

Mutations of genetic structure of plants Mutations of genetic structure of plants and animalsand animals

Page 46: Environment 2015

Results of Ozone DepletionResults of Ozone Depletion

Reduces rate Reduces rate of of photosynthesisphotosynthesis in plants in plants (lowers energy (lowers energy output of output of producers)producers)

Page 47: Environment 2015

Possible Responses to Ozone DepletionPossible Responses to Ozone Depletion

Montreal Protocol Montreal Protocol – 1987– 1987 Agreement Agreement

between all between all industrial nations industrial nations to cut use of to cut use of CFCs in an effort CFCs in an effort to eliminate these to eliminate these chemicals by chemicals by 20002000

http://www.youtube.com/watch?v=Dn3KvZ_Xyqs&feature=related

Page 48: Environment 2015

Possible Responses to Ozone DepletionPossible Responses to Ozone Depletion

Avoid using plastic foam packaging and Avoid using plastic foam packaging and goods that use CFCs (some aerosol cans)goods that use CFCs (some aerosol cans)

Page 49: Environment 2015

Possible Responses to Ozone DepletionPossible Responses to Ozone Depletion

Dispose of old Dispose of old refrigerators, refrigerators, freezers, and freezers, and air air conditioners conditioners safelysafely

Page 50: Environment 2015

Fresh Water SuppliesFresh Water Supplies 70% of Earth’s Surface – covered by water70% of Earth’s Surface – covered by water However- most not readily accessible for However- most not readily accessible for

human usehuman use

Page 51: Environment 2015

Fresh WaterFresh Water

Water stored in:Water stored in: SoilSoil Aquifers Aquifers

(Ground water)(Ground water) LakesLakes RiversRivers streamsstreams

Page 52: Environment 2015

Fresh WaterFresh Water Only 3% fresh water – 78% of which is Only 3% fresh water – 78% of which is

stored in ice caps and glaciersstored in ice caps and glaciers Canada has 18% of all surface fresh water Canada has 18% of all surface fresh water

on Earthon Earth Large Large

portion ofportion ofthis in this in Great LakesGreat Lakes

Page 53: Environment 2015

Fresh Water Issues Fresh Water Issues in Developing Worldin Developing World

Mismanagement / OveruseMismanagement / Overuse Limited accessLimited access Lack of proper sanitation Lack of proper sanitation

systemssystems Lack of water treatment Lack of water treatment

facilitiesfacilities DroughtDrought Privatization (water is Privatization (water is

owned by a private owned by a private company and is expensive company and is expensive to buy)to buy)

Cost (poorest of poor Cost (poorest of poor cannot afford)cannot afford)

Page 54: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

ContaminationContamination Oil tanker accidentsOil tanker accidents Natural causesNatural causes Dumping of wasteDumping of waste

Page 55: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

ContaminationContamination Agricultural Agricultural

• Chemicals used in herbicides / pesticidesChemicals used in herbicides / pesticides• Can seep into nearby streams and ground waterCan seep into nearby streams and ground water

Page 56: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

ContaminationContamination Industrial Industrial

• By-products of production in oil refineries, pulp By-products of production in oil refineries, pulp mills, nuclear reactors, and chemical factoriesmills, nuclear reactors, and chemical factories

Page 57: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

ContaminationContamination MunicipalMunicipal

• Raw sewage, detergents, and solventsRaw sewage, detergents, and solvents

Page 58: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

MisuseMisuse 67% of accessible 67% of accessible

surface water is surface water is used by agricultureused by agriculture

When farmers till When farmers till land – lose moisture land – lose moisture – so land is – so land is irrigated irrigated – watered by – watered by artificial meansartificial means

Page 59: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

MisuseMisuse 19% fresh water used for industry19% fresh water used for industry 9% for municipal / residential services9% for municipal / residential services

Page 60: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

Groundwater Groundwater DepletionDepletion Over pumping of Over pumping of

aquifers aquifers (underground layer (underground layer of water-of water-permeable rock) permeable rock) which replenish which replenish slowly reduces the slowly reduces the water table (top of water table (top of saturated layer of saturated layer of porous rock – porous rock – ground water)ground water)

Page 61: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

Groundwater DepletionGroundwater Depletion Digging deeper wells which could potentially Digging deeper wells which could potentially

tap harmful minerals like arsenic and fluoridetap harmful minerals like arsenic and fluoride

Page 62: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

Page 63: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

Water ExportsWater Exports The transfer water over long distancesThe transfer water over long distances Example: California would like to buy BC water; Example: California would like to buy BC water;

however, this could influence water table levels in BChowever, this could influence water table levels in BC

Page 64: Environment 2015

Threats to Water Quality and Threats to Water Quality and Supply in CanadaSupply in Canada

Increasing PopulationsIncreasing Populations Main threat to world’s freshwater supply’s Main threat to world’s freshwater supply’s

shortages threaten world agricultural shortages threaten world agricultural production as the amount to irrigated land has production as the amount to irrigated land has more than doubled in the 2more than doubled in the 2ndnd half of the 20 half of the 20ththCC

Page 65: Environment 2015

Possible Possible SolutionsSolutions to Water Supply Threats to Water Supply Threats

Treatment technologies (Water Treatment Treatment technologies (Water Treatment Plants)Plants)

Page 66: Environment 2015

Possible Solutions to Water Supply ThreatsPossible Solutions to Water Supply Threats

DesalinationDesalination of sea water (remove salt) of sea water (remove salt)

Page 67: Environment 2015

Possible Solutions to Water Supply ThreatsPossible Solutions to Water Supply Threats

Reclaimed or recycled water technologiesReclaimed or recycled water technologies Rainwater harvestingRainwater harvesting

Page 68: Environment 2015

Possible Solutions to Water Supply ThreatsPossible Solutions to Water Supply Threats

ConservationConservation Low energy sprinkler systems and Low energy sprinkler systems and

washing machineswashing machines Low flush toilets and other small-scale Low flush toilets and other small-scale

supply systemssupply systems Water Management technologyWater Management technology

Page 69: Environment 2015
Page 70: Environment 2015

Possible Solutions to Water Supply ThreatsPossible Solutions to Water Supply Threats

Farmers change watering schedules to Farmers change watering schedules to coincide with seasonal rainscoincide with seasonal rains

Shallow wells or use new technology / Shallow wells or use new technology / techniques in well drilling so farmers are techniques in well drilling so farmers are able to tap groundwater in aquifers able to tap groundwater in aquifers

Drip irrigationDrip irrigation which directs which directs water to plant roots – water to plant roots – less evaporationless evaporation

Page 71: Environment 2015

Possible Solutions to Water Supply ThreatsPossible Solutions to Water Supply Threats

Micro-dams Micro-dams rather than large-scale rather than large-scale projects that cause major harm to the projects that cause major harm to the environmentenvironment

Stronger Stronger government regulationsgovernment regulations Taxes or user ratesTaxes or user rates

could be introduced to could be introduced to encourage encourage conservationconservation

Set Set watering patternswatering patterns within municipalities within municipalities

Page 72: Environment 2015

Acid RainAcid Rain Precipitation Precipitation

(rain, snow, hail, (rain, snow, hail, or fog) with a or fog) with a pH level of less pH level of less then 5.6then 5.6

Caused by Caused by heavy industrial heavy industrial activity with activity with acids like acids like sulphur dioxide, sulphur dioxide, nitrogen oxide, nitrogen oxide, and burning and burning fossil fuelsfossil fuels

Page 73: Environment 2015

Acid RainAcid Rain Can poison plant life Can poison plant life

and wildlife of an areaand wildlife of an area Cause genetic Cause genetic

mutationsmutations Decrease growth rates Decrease growth rates

of treesof trees Corrode steelCorrode steel Affect lung capacity in Affect lung capacity in

humanshumans Especially predominant Especially predominant

in Great Lakes areain Great Lakes area

Page 74: Environment 2015

Acid Rain - ResponseAcid Rain - Response

Canada- United States Canada- United States Air Quality Air Quality AgreementAgreement signed by Canada and the signed by Canada and the US in Ottawa - 1991 US in Ottawa - 1991

addresses transboundary air pollution addresses transboundary air pollution leading to acid rain leading to acid rain

Page 75: Environment 2015

DeforestationDeforestation

Page 76: Environment 2015

DeforestationDeforestation The permanent loss of old growth forestsThe permanent loss of old growth forests Has a drastic effect on the forests of the worldHas a drastic effect on the forests of the world Important to the recycling of carbon dioxide, and Important to the recycling of carbon dioxide, and

the release of oxygen into the atmospherethe release of oxygen into the atmosphere Leads to more Leads to more

global warmingglobal warming Survival of someSurvival of some

species threatenedspecies threatened

Page 77: Environment 2015

DeforestationDeforestation Brazilian RainforestBrazilian Rainforest

Develop rainforest Develop rainforest through farming, through farming, cattle ranching, cattle ranching, mining, and mining, and lumberinglumbering

Often no reforestation Often no reforestation occurs and removal occurs and removal of forests lead to dry of forests lead to dry wastelandswastelands

http://www.youtube.com/watch?v=Gqk_sre54WA&feature=related

Page 78: Environment 2015

Nearby bodies of water Nearby bodies of water because soil no longer because soil no longer covered by forest, it covered by forest, it becomes stripped away by becomes stripped away by rain or snowrain or snow

Washed-out soil raises Washed-out soil raises riverbeds, which leads to riverbeds, which leads to flooding, clogs reservoirs, flooding, clogs reservoirs, and shortens life of damsand shortens life of dams

Also contributes to formation Also contributes to formation of new islands, which of new islands, which depletes coastal fisheriesdepletes coastal fisheries

Many insect, animal, and Many insect, animal, and plant species have become plant species have become extinct or endangered due extinct or endangered due to deforestationto deforestation

Deforestation AffectsDeforestation Affects

Page 79: Environment 2015

Canada’s ForestsCanada’s Forests Canada has:Canada has:

¼ of the world’s ¼ of the world’s temperate temperate deciduous coastal deciduous coastal forestforest

1/3 of world’s 1/3 of world’s boreal coniferous boreal coniferous forestforest

Virtually all of the Virtually all of the world’s old growth world’s old growth pinepine

Page 80: Environment 2015

Decline of Canada’s Forests due toDecline of Canada’s Forests due to Forest firesForest fires Industrial Industrial

developmentdevelopment LoggingLogging In BC: In BC:

Pine Beetle Pine Beetle EpidemicEpidemic

• Largely due to Largely due to global warmingglobal warming

• Winters not cold Winters not cold enough to kill enough to kill themthem

Page 81: Environment 2015

DesertificationDesertification

Page 82: Environment 2015

DesertificationDesertification Expansion of deserts Expansion of deserts

due to due to mismanagement of the mismanagement of the land in agricultureland in agriculture

Using too much Using too much irrigation and artificial irrigation and artificial fertilizers to grow food fertilizers to grow food out of season can make out of season can make soils too salty to soils too salty to continue to grow cropscontinue to grow crops

Farmland can become Farmland can become a wasteland or desert a wasteland or desert on which very little can on which very little can grow or survivegrow or survive

Page 83: Environment 2015

DesertificationDesertification process whereby the productivity of drought- process whereby the productivity of drought-

prone land decreases because of a variety of prone land decreases because of a variety of factors including:factors including:

overgrazing (poor rangeland management), overgrazing (poor rangeland management), poor irrigation (waterlogging and salinization),poor irrigation (waterlogging and salinization), deforestation, deforestation, Over-cultivation, Over-cultivation, drought, drought, soil erosion, soil erosion, chemical action chemical action and other practices. and other practices.

http://www.youtube.com/watch?v=zLBYfyp24Xc&feature=related

Page 84: Environment 2015

Desertification and Global WarmingDesertification and Global Warming One of the impacts One of the impacts

which global warming which global warming may have on the may have on the surface of the Earth surface of the Earth is to exacerbate the is to exacerbate the worldwide problem of worldwide problem of desertification. desertification.

A decrease in the A decrease in the total amount of total amount of rainfall in arid and rainfall in arid and semi-arid areas could semi-arid areas could increase the total increase the total area of drylands area of drylands worldwide, and thus worldwide, and thus the total amount of the total amount of land potentially at land potentially at risk from risk from desertification.desertification.