GEF

11 Introduction UNIT4 | TheGlobal ecosysTem 87 The icebergmodel isauseful systems thinking tool to lead us to lookbeyondwhat isfirstnoticedaboutaproblemand deeper into the linkedcauses.The simple factsofan issue makeup the tipof the iceberg.Forclimatechange, thiswould be today’snewsof rising temperatures,melting icecaps,natu- raldisasters,andother symptomsofclimatechange. Above theWaterline Below theWaterline The icebergmodelencouragesus to lookbelow the surfaceof challenges. Themajorityof the iceberg,which isharder to see, represents the rootcausesof the symptoms.Thesecauses include factors suchashowweuseenergyand resources,aswellasouratti- tudesabout theenvironment.Thegoalof the icebergmodel is todemonstrate that realchangebecomespossiblebyunder- standing rootcausesandpatterns. AlbertEinstein said, “Wecan’t solveproblemsbyusing the samekindof thinkingweusedwhenwecreated them.”Systems thinkingand the triplebottom linearenewways to look for successful solutions toproblems. ICEBERG MODEL A systems thinkingmethod that looksbelow the simple factsofan issue to investi- gatecausesandpatterns. ? DIDYOUKNOW? In 1996,NewYorkCitywas facedwith theprospectof buildingawaterfiltration plantatanestimatedcostof $8billionaftercitywaterno longermetEnvironmental ProtectionAgency stan- dards. Instead, thecitychose to investabout$1.5billion inecosystem restoration in theCatskillMountains, the sourceofNYCwater. In this case,valuing thepurifying serviceof thisecosystem provedmoreeffectiveand cheaper thanbuildinga water treatmentplant. Ecosystem services isagrow- ingfieldwithin sustainability. UNIT4 | TheGlobal ecosysTem 88 checK yoUR UNDeRsTaNDING 1. Howold is theEarth?Whendid thefirstmodernhumansemerge? 2. Whycan theEarthbeviewedasa system?Whatare the fourmain systems,or “spheres,” thatmakeup theEarth? 3. Whatare the threemost importantbiogeochemicalcycles that link theEarth’s systems together?Howarehumansdependenton thesecycles?Howdohumans impact thesecycles? 4. What isanecosystem?Why is“thinking likeanecosystem”avitalcomponent ofpracticing sustainability?How isanunderstandingofecosystem services important forbuilding sustainable societies? 5. How is sustainabilityan integratingconcept?Why is systems thinkingnecessary andhelpful for sustainabilityeducation? GROWYOURKNOWLEDGE Biogeochemicalcycles link theatmosphere,hydrosphere,biosphere, and lithosphereEarth systems.Studying thesecyclesnotonly shows the linkbetweenEarth systems,butalsohowhumanactivity impacts these systems. In thisactivity,youwillexploreoneof thecycles discussed in thisunit. 1. Chooseoneof the threebiogeochemicalcyclesexplored in thisunit—carbon, water,ornitrogen.Visit theNationalCenter forAtmosphericResearchWebsite (eo.ucar.edu/kids/green/cycles1.htm) to reviewyour selectedcycle. 2. Identify thebenefitsofyour selectedcycle.Why is thiscycle important?Makea list of severalof thekeybenefits thatyou think thiscycleprovides tohumans,plants, animals,and/orother livingorganisms.Your listmay range fromgeneral (e.g., “helpsplantsgrow”) to specific (e.g.,“fillsmy rainbarrel”). 3. Identify thehuman impactsonyour selectedcycle.Howdohumans interactwith thiscycle?List severalexamplesof thewaysyou thinkhumans interactwith this cycle.Your listmay includepositive interactions (e.g.,“usingcompost ingardens”) aswellasnegative interactions (e.g.,“drivingcars thatemitgreenhousegases”). Grow You Knowledge activities—one at the beginning of the unit and one at the end—provide hands-on opportunities to explore additional areas of sustainability. Did You Know? sidebars introduce facts and notes about sustainability issues. The Check Your Understanding questions at the end of each unit allow you to revisit the self-assessment statements to recognize how your knowledge has grown.