Ecological Economics 生态经济学ppt课件.ppt

Ecologicaleconomics.AnintroductorycourseAutumn2011,RalfErikssonEconomicsSchoolofBusinessandEconomicsboAkademiUniversityUniPiD,1,Lecture1.,Introductionandconceptualbackground,2,Thestructureofthecourse,Thecourseconsistsof10modulesofwhich9istheactualcourseworkandthe10thisreservedforexami.e.Weeks38-47(5credits)5creditsN.B.thechangecomparedtothepreliminarycoursedescription!,3,Coursecontentinbrief:,IntroductionandthegeneralpolicyperspectiverequiredbysustainabilityeconomicgrowthinahistoricalperspectiveEthicsandecologicaleconomicsEnvironmentaleconomicssustainabilityconceptionsandmeasurementwithinecologicaleconomicseconomicsandethicsofclimatechangeglobalfoodsecuritythestateoftheseasonearthandlocally(theBalticSea)thepossibilityofdegrowthN.B.thechangetothepreliminarycoursecontent!,4,TheGoalofthecourse,TogiveanintroductiontothedisciplineofecologicaleconomicsTodiscussdifferentperspectivesonecologicaleconomicsproblemsandtheirsolutions,5,Literature,Eriksson,R.andthattheobjectiveofeconomicpolicyshouldnotbetomaximiseit,i.e.toenableustomaintainourcapitalstockwithaslittleconsumptionorproductionaspossible(Boulding,Daly1996),23,Pointofdeparture:Theglobalethicaltrilemma,24,Figure1.1theglobalethicalTRILEMMAPicktwoignorethethird,MassconsumptionProsperityGlobalsocial-Eco-efficientdemocracycapitalismGlobalEcologicaljusticesustainabilityRed-greenplanetarism,25,Thecornersofthetrianglecorrespondtothethreecomponentsoftenincludedinthedefinitionsofsustainabledevelopment:theecological,theeconomicandthesocialdimensions.Inpracticeitisimpossibletoreachallthree,26,Prosperity,Rostowsstage-theory(economicgrowthitliketheflightofanairplane)Thegoal,andfinalstagewastheageofhighmass-consumption.WhenRostowwrotethis(1960)noattentionwaspaidtothenaturalenvironmentEconomicgrowthisstillthestandardforsuccessglobally!,27,Justice,Onepossibledefinitioncouldbebasedoncapabilities(A.Sen)Aregimewillbedeemedjustifandtothedegreethatitpromotesharmonizationofcapabilitiestoachievefunctioningsatalevelthatissufficient,universallyattainableandsustainable.(DeMartino,s.144),28,Theworldishardlyjusttoday,Income(comparedintermsofmarketexchangeratesMERamongtherespectivecurrencies)ismorethan70timeshigher.Income(comparedintermsofpurchasingpowerparityexchangerates)isreckonedasmorethan10timeshigher.Consumptionofanimalfoodis7timeshigher.Releaseofcarbondioxideis22timeshigher.Consumptionofelectricityis35timeshigher.Consumptionofpaperis89timeshigher.,29,Ecologicalsustainability,Sustainability(insomesensetobediscussedinchapter5)becomeafundamentalvaluecomparabletolibertyorjustice.Onewayofmeasuringecol.SustainabilityistheecologicalfootprintWhichshowsthehumanpressureonecosystems,30,Figure1.2globalecologicalovershootfromthe1960stothe2050s,31,Figure1.2showshowtheglobalecologicalfootprinthasincreasedsincethe1960sandhowitisexpectedtogrowifhumankindcontinuestoincreaseitsconsumptionofnaturalresources.ArapidreductionwouldbenecessarytobringdowntheglobalfootprinttoalevelthatisconsistentwithEarthslimitedbiocapacity.,32,Picktwoignorethethird,Theethicaltrilemmaderivesfromthedifficultytoachieveallthreegoalssimultaneously.Itisrelativelyeasytopickoneofthecornersandtofindoutwhatwouldberequiredtoachievethatspecificgoal.Youcanreadbooksonhowtopromoteeconomicgrowth,howtoreduceinequitiesorhowtoavoidenvironmentaldegradation,butitismuchhardertofindworksthattreatallthreeevenjusttwoofthegoalsatthesametime.,33,Thedominatingpolicytodayisperhapstheonethatstressesgrowth,i.e.thetopofthetriangle(Figure1.1)AcombinationofProsperityandJusticecouldbeastandard(global)socialdemocraticview.Whereasmostenvironmentaleconomistsaresituatedonthesideof“eco-efficientcapitalism”ecologicaleconomiststendtohaveapenchanttowards“red-greenplanetarism”.,34,Thebiganddifficulttaskwouldbetotakeallthecornersintoconsideration.Wewillcomebacktothisprobleminthelastchapter(module)ofthiscourse.,35,Lecture2.economicgrowthandhumandevelopment,36,THEIPATEQUATION,I=PxAxTwhere:IstandsforenvironmentalimpactPstandsforpopulationAstandsforconsumptionpercapitaoraffluenceTstandsforthroughputnaturalresoursesusedperunitofconsumption;itislargelydependentonthetechnologyusedintheproductionofgoodsandservices,37,Forexamplelikeabove,WorldpopulationxGDPpercapitaxTonnesofnaturalresources/GlobalGDPGDPGrossDomesticProductisthevalueinmonetarytermsofthegoodsandservicesproducedinacountry.ItisalsoroughlyequaltotheGNItheGrossNationalIncomeofthecountry.GNIcomprisesthetotalvalueproducedwithinacountry(i.e.itsGDP),togetherwithitsincomesreceivedfromlesspaymentsmadetoothercountries.OnagloballevelGDPisexactlyequaltoGNI.,38,Table2.1Lifeexpectancy,1000-2003(yearsatbirthforbothsexescombined),39,2.2.Population(millions)1-2030,40,LevelsofpercapitaGDP(1990$),41,Sixtypesofcapital,Naturalcapitalisphysicalassetsprovidedbynature;naturalresourcesandamenitiesthatdeliverservicestotheeconomy.Theyaregenerallyreproducednaturally,withouthumaninterference,butsincehumansnowadaysareabletoremakenatureonamassivescale,naturalcapitalcanbedegradedanddestroyed,butalsoenhancedandcreated,42,2.Manufacturedcapitalcorrespondstothe“realcapital”oftheclassicaleconomists.Itconsistsofman-madeequipment,buildingsandinfrastructuresthatareusedforproductivepurposes.Manufacturedcapitalwearsoutandmustbereplacedbyinvestmentsinnewtools,machinery,vehicles,buildings,etc.,43,3.Humancapitalconsistsofthemotivations,skillsandknowledgeoftheworkers.Investmentinhumancapitalinvolvesupbringing,education,trainingandexperience.,44,4.Intellectualcapitalisthepoolofknowledgeandideasaccumulatedinculturalartefacts,suchasbooksandcomputermemories.Discoveries,innovations,recipes,scientificresults,fictionandplays,compositionsandpicturescanbestoredandreused.Evenifthematerialsencodingtheideasmaywearout,theideasinfactdepreciatelessthemoretheyareused.Intellectualcapitalisoftenmergedwithhumancapital,buttherearegoodreasonstoseparatethetwo.Oneisthatthereproductionofintellectualcapitalispracticallydelinkedfromtheuseofscarcenaturalresources,andthereforeofgreatinterestfromanecologicalpointofview.,45,5.Socialcapitalisembeddedinthecultureandinstitutionsofasociety.Trust,mutualunderstanding,andsharedvaluesarecrucialforeconomiccooperation.Activitiessuchaspolitics,legislationandgovernancecanimprovesocialcapital.Culturalnorms,customsandinstitutionsdonotwearout,buttheymaybecomeobsoleteanddysfunctionalastimeschanges.,46,6.Financialcapital,alsocalledfictivecapitalincontrastto“realcapital”,isfundsofpurchasingpowernecessaryforfacilitatingtransactionsandinvestmentsinacapitalisteconomy.Sincefinancialcapitalconsistsofsymbolicassets,suchasloans,currencies,stocks,futuresandderivatives,astronomicalamountscanbetransactedcheaplyandalmostinstantly.,47,Energy,entropy.andecologicalfootprint,Accordingtotheentropylaw(2ndlawoftermodynamicstheorderintheuniversetendstodecreas:theuseofnon-renauvablenaturalresourcesmakestheorderincreasesuchawhenoilipumpedupandmadeunusefulwhenuseddifferentenginesHoweever,solarenergyis(fromhumanperspective)renewable,thanksmostlytophostynthesis(seeslides21and22inlecture1),48,.andecologicalfootprint,Ecologicalfootprint(EF)isameasureoftheuseofrenewableresources.EFisameasureexpressedinthelandandwater(inhectares)toproducewhattheeconomyconsumesandrequiresfortoabsorbwaste.UsingourIPATequationwecanmeasuretheglobalenvironmentalimpactintermsofecologicalfootprintsinthefollowingway:Impact=PopulationxGDP/capitaxEF/GDPSinceweliveinafullworldtheEF/GDPrelationshouldbedimished.,49,Strongandweaksustainability,Howsubstitublearenaturalresourcestomanmadecapitalresources?WEAKSUSTAINABILIYisthestandardassumptionofmainstreameconomics;NaturalresourcesaresubstitutablebymanmaderesourcesSTRONGSUSTAINABILITYistheassumptionofecologicaleconomics;therearecriticallimitsofthenaturalresourcesthatshouldnotbeexceed,andcannotberecoveredbybuilt(artifical)systems,50,Decouplingandthereboundeffect,Howmuchcanthroughputbereducedinrelationtoconsumptionbytechnologicalimprovements?Isitpossibletodecoupletheuseofenergyandothernaturalresourcesfromtheproductionofgoodsandservices,51,Decouplingandthereboundeffect,cont.,Optimisticview:EnvironmentalKuznetsCurve(EKC):astheeconomyreachesacertainlevelofindustrialmaturity,moreeffortswillbedirectedtowardsthealleviationofenvironmentalproblems.Pessimisticview:IfIcansavemoneybyusingelectricalequipmentthatrequirelessenergy,butspendthisextramoneyonacheapflight,onecanhardlysaythatIhavecontributedtodecoupling.,52,Ecologicaleconomicsisoneimportantpartofanongoingrevolutionineconomicsthatdeemphasizestraditionaleconomicgrowth,andlookforaneconomicsconcernedwiththequalityoflife,careandsustainability.Otherimportantcontributionshavebeenmadebysocialeconomists,feministeconomists,institutionaleconomistsandbehavioraleconomists.,53,Caring,happinessandsustainability,Mostcaringworkhasnotbeenincludedinthemeasurementofeconomicproductionandwellbeing,despitethefactthatitconstitutesalargepartofallworkandlife.Anotherimportantfindingisthatforalreadyrichsocietiesprosperity,inabroadsenseoftheterm,nolongerislinkedtohigherincomesandconsumption.Variablessuchaslifeexpectancy,childmortality,levelofeducationandsubjectivelifesatisfactionarerelatedtoincomeuptolevelsbelow1500020000dollarpercapita,butabovethisthresholdtheserelationshipsareblurred.(Easterlinparadox),54,Howthemarketmechanism/pricesystemworksaccordingtotheoryBasedonchapter4ofErikssonandandersson,Environmentaleconomics,55,Howmarketswork.Figure4.1,Price/kilos12.000SupplyP*2500DemandQ*1000kilos,56,Howmarketswork,cont.,InFigure4.1thedownward-slopingline(Demand)describesthebehaviorofthefishbuyers:thehigherthepricethelessthebuyerswanttobuyandconversely.Thebehaviorofthesellers(suppliers)isdescribedbythesupplycurveline.Thehighertheprice,themorethesellerswanttosell(themoreintensivelythefishiscaught).Thus,expressedintherelationbetweenpriceandbought/soldfish,thewishesofthebuyers/sellersaretheopposite.Onlyatonepoint,say,attheprice5,000yenandthequantitysold500kilosdothesellersandbuyersagree.Atthisequilibriumprice(oftenshortenedasP*)theconsumersmarginalwillingnesstopaycorrespondstothemarginalcost(theadditionincostcausedbytheincreaseofthelastentityofthegoods,e.g.wages,materials,fueletc.)ofselling.Itshouldbenotedthattheexamplehereisnotquiterealisticbutjustintendedtogivethebroadoutlines(Forinstanceinreality,thebiggerthetunathehigherpriceperkilogram).AtthefirstTunaactionatTsukijifishmarketinTokioin2008thepricefortunawas22000yen(202dollars)perkilo,whichmeantapriceof$55700forthefishof276kilogram.,57,Howmarketswork,cont.,ThismeansthatthequantityQ*soldatpriceP*givesthebestpossibleeconomicresultforthemarketasawhole.Inotherwords,itisnotpossibletochangetheallocationofgoodsinawaythatsomepeoplewouldfareaswellasbeforewhilesomeatthesametimewouldbebetteroff(thisiscalledParetooptimum,namedaftertheSwisseconomistWilfredoPareto).,58,Theassumptionsforperfectcompetition,However,notethatthisresultistrueonlyiftheassumptionsthatthemodelrestsonaretrue.TheseassumptionsareThenumberofconsumersandproducersisverylargeThegoodsarehomogenous(noproductdiversificationoradvertising)Allactorsonthemarkethavefullinformationaboutalltherelevantfeaturesofthemarket,suchaspricesetc.Freeentryandexit(nocostsforestablishinginamarketorgoingoutfromit),59,Assumptions,cont.,Howcommonarethesecharacteristicsintherealworld?Thinkaboutit!Actually,theseassumptionsarerequirementsthatmakepossiblerationalbehavioronthemarketThisassumptionsarehardlyeverfulfilledonanymarket,atleastnotall!Still,thismodelisconsideredusefultoanalyzetherealeconomy.Becauseevenifallpeoplearenotrationalallthetime,onemaybelievethatmostpeoplebehaverationallymostofthetime(sufficientrationality),60,Figure4.2.Themarketequilibrium,Excesssupply,61,Marketequilibrium,Thecentralfeatureofamarketasillustratedbyfigure4.2isitstendencytowardsequilibrium,whichisdepictedbypointofintersection(E*,withequilibriumpriceP*,andequilibriumquantityQ*atwhichsellerswishtosellasmuchasbuyerswanttobuy.Tounderstandthistendency,assumethatthepriceishigher,asP.Whathappensnow?AtPwecandrawahorizontallineandbythatseewhatthecorrespondingdemandandsupplyisfromtheintersections.Wecansee(withoutknowingtheexactQ-scale,thatsupply(S-line)isrelativelymuchbiggerthandemand(D-line).Thisdifference(distance)wecallexcesssupply.,62,Marketequilibrium,cont.,Understandingthiswenowmayask,whathappensonthemarketundertheseconditions?Inotherwords:whathappensif(thepriceissohighthat)buyerswanttobuylessthanthesellerswanttosell?Itmighthelptoconcretizethesituationabit:whathappensonafishmarketwhennotallcaughtfishcanbesold?Asallgoodstheybegintopileupinstock.However,theproblemwithfishisthatthequalitywillquicklybegintodeteriorate.Itcanbekeptincoldorfrozen,butthequalitystillkeepsdeteriorating,soactuallyitseconomicvaluealsodeterioratesallthetime.Sowhatdoesafish-sellerdo?Heknowthatitwillbewisetogetthefishsoldassoonaspossible.Theonlyoptiontomakethispossibleistolowertheprice.,63,Marketequilibrium,cont.,Whenpriceislowered,peoplewillbuymore(demandwillrise,ascanbeseenbydrawingalineunderPinfigure4.2)-excesssupplydiminishes.IfthisthinkingiscorrectitwillbesoatallpricesunderPaslongasweareaboveP*!ThethoughtexperimentcanberepeatedforsomepriceunderP*,asituationwitha”ceilingprice”.Suchsituationsmayoccure.g.whenthereisafoodshortagewhenthegovernmentwantstomakesurethatalsopoorpeoplecanaffordtobuyfood.Insuchasituationablackmarketmayarise,whichmeansthatan(illegal)marketisinworkwherepricesrise.,64,InbothcasesthereisanautomatictendencytowardsthepriceP*andequilibrium(E*)Importanttokeepinmindhereisthattheseequilibratingforcesfunctiononlywhentheassumptionsa)-d)arevalid.Underothertypesof”marketfailures”,asforinstancemonopoly,i.e.themarketfailurethatthereisonlyoneseller,theequilibriumpricewillnotbereachedbutwillbehigher,exactlybecauseofthemarketpowerofthemonopolist,whocanbykeepingthesupplysmallerthanunderperfectcompetition,keepthepricehigher.,65,Perfectcompetitionintheperspectiveofanindividualfirm,Figure4.3illustratesonefundamentalfeatureoftheperfectcompetitionmarket,whichisthefeaturethatfromthepointofviewofasingleseller(aswellasbuyer)pricemustbetakenasgiven.Whyisthat?Thiscanbeintuitivelyunderstoodatleastfromtwopointsofview:1)afirmonacompetitivemarketisonlya“dropinthesea”,i.e.itsproductiondecisionhasnoeffectwhatsoeveronthetotalsupplyofthemarketandthusnotontheprice!2)orifasinglefirmshouldraiseitsprice,arationalconsumerwouldnotbuyfromthatfirm,becausehecouldbuythegoodcheaperfromsomeotherfirms.,66,Inperfectcompetition,thefirmisthuscalledaprice-taker.Fromthisthereisashortsteptotheeconomicallyimportantconceptofmarginalrevenue.Themarginalrevenueistheadditionalrevenue(income)whichthefirmgetsfromanadditionalsoldunitofthegood.Inperfectcompetitionmarginalrevenueisidenticalwiththeprice.Regardlessofwhetheryousell1kgor10,000kgsyourpricewillbethesame(sinceyourproductionisminimalcomparedtothewholemarketasthetroutmarketinfigure4.3),Perfectcompetitionintheperspectiveofanindividualfirm,contd,67,Perfectcompetition:thetroutmarket,Thisunderstood(verify!)infigure4.3theupshotofthisisthat,fromthepointofviewofasinglefirm,thedemandcurvewillbeahorizontalline(MR)Despitethefactthatthedemandcurveforthewholemarketisslopingdownward!Thisisbecauseforthesinglefirmonlymarket(equilibrium)single/givenpriceiswhatmatters!,68,Figure4.3.Marginalrevenue,P,69,Marginalcostandmarginalrevenue,NowweunderstandwhattheTotalIncomeis:Price(=MR)xQuantity(verifythatyouunderstandthisfromfigure4.3;geometricallyitistheboxofPricetimeswhateveramountyousell(e.g.ifpriceis1andyousell1kg,totalincomeis1,ifyousell10,000totalincomeis10,000,etc.)However,tobeabletosaysomethingabouthowmuchtoproducei.e.togetthehighestprofitweshouldalsoknowwhatthecostsofproductionare.,70,Marginalcosts,Thetotalcostsareusuallydividedintofixedcosts(FC)andvariablecosts(VC).Thefixedcostsdonotchangewithproducedquantity.Forexampleforthefishfarmerthecostsforafishcage(abignetbagwherethefishisgrown)isthesameindependentlyofwhetherheisfarmingoneorathousandsoffish.Variablecosts,conversely,varywithproductionquantity.Ifthefishfarmerwantstoproducemorehemuste.g.buyjuvenilefish,morefodderetc.Ineconomicstheanalysisisoftensimplifiedbyneglectingthefixedcosts,thatareconsideredasconstant,andinsteadconcentratingonthevariablecostsinmarginalterms(i.e.changeinMCwhenproductionchangesoneunit)(MVC).AtypicalMVC-curveisdrawninFigure4.4.,71,Figure4.4.Marginalvariablecostandmarginalrevenue,72,MCandMR,Fig.4.4simplyshowsmarginal(additional)revenue(+)andcost(-)foreachadditionalproducedunit.Wecanseethatforeachadditionalproducedunitthecostsaresinkingtillthe10thunit.Thismeansthatuptothispointproductivityisrising.AfterthispointtheMVC-curvebeginstorise,whichmeansthatproductivityisdiminishing.Howmuchshouldweproduce?Inotherwords,whichproductiongivesusthehighestprofit(Totalrevenuesminustotalbenefits),73,MCandMR,cont.,Inthefig.4.4thetotalrevenueisgivenbyadditionofallcolumnsundertheP=MRlinetoacertainquantity.Thetotalcost(disregardingfixcosts)isgivenbythecorrespondingadditionthecolumnsundertheMVCcurve.Inthefiguretotalcostsarethusgivenbyallthewhitecolumnsandtotalrevenuesbythecoloredcolumns.Thus,ateachlevelofproductiontheprofitwillbethetotalwhiteareaminusthetotalcoloredarea.Howmuch,then,shouldbeproduced(sold)togetthegreatestprofit?Simple;choosetheproductionquantitywherethewhiteareainthefigureisatitsbiggest!ThatisQ*.Thinkaboutit:whynotchooseproductionat10?,74,MC=MR?,WhatFigure4.4.illustratesis“Thefundamentaleconomicprinciple”:alleconomicactivityshallbeexpandedtothepointwheremarginalcostisequaltomarginalrevenue:MC=MR!,75,Thewillingnesstopayandconsumersurplus,Thereisbutashortsteptounderstandthatthedemandcurvebesidesshowinghowmuchconsumersdemandatdifferentpricesisatthesametimetellinghowmuchtheyarewillingtopay(WillingnessToPay(WTP)fordifferentamountofgoods.So,forinstance,ataveryhighpriceoftuna(12.000ormore)therearejustafewpeoplewhodesireitand/orarerichenoughtobythetunaatthatprice.Asthepricegoesdowntherearemoreandmorepeoplewilling(and/orwhocanafford)tobuythetuna.InfacttheywouldbewillingtopaymorethanthepriceP*,buttheygetthetunaatthisprice,sotheyreceiveasurplusinasituationlikethis.Thisiscalledtheconsumersurplus.(Cf.figure4.5),76,Price/kilo,12.00