Theprincipleof"commonbutdifferentiatedresponsibilities"isthecornerstoneoftheUnitedNationsFrameworkConventiononClimateChange(UNFCCC),formedin1992andnowratifiedby192countries.
Theprincipleservesasanimportantreasonwhytheworld'scountries,allwithmanydifferencesintheirrespectiveinterestsandconcerns,couldsitdowntogethertonegotiateasolutionforthepressingissueofclimatechange.
Theword"common"showsthatfightingclimatechangeisanobligationforeverycountryaroundtheworld.
Undoubtedly,whentheearth,mankind'scommonhomeland,isfacingacrisis,peoplearoundtheglobemustworktogetherandhelpeachothertofindasolution.
However,letusnotforgetthattheresponsibilitiesarenotonly"common"butalso"differentiated."
Theindustrializedcountries,withabundantfinancialresourcesandadvancedtechnologies,shouldshouldertheirhistoricalresponsibilitiesandmaketangiblemovestodealwiththeirhighpercapitacarbondioxideemissions.
Asforthedevelopingcountries,"economicandsocialdevelopmentandpovertyeradicationarethefirstandoverridingpriorities,"theconventionsaid.
Takingintofullconsiderationthedifferentsocio-economiccontexts,historicalresponsibilities,andpercapitaemissionsofvariouscountries,theconventionstipulatesthat:developedcountriesshouldtaketheleadincombatingclimatechangeandprovidefinancialresources,includingthetransferoftechnology,fordevelopingcountries.
Withthefundsandtechnologicalsupportprovided,developingcountriesneedtoadoptmeasurestomitigateandadapttoclimatechange,accordingtotheconvention.
In1997,thethirdsessionoftheConferenceofthePartiestotheUNFCCCheldinJapanadoptedtheKyotoProtocol,which,forthefirsttimeinhistory,madetheprincipleof"commonbutdifferentiatedresponsibilities"becomealegallybindingcommitment.
TheUnitedStates,reluctanttoaccepttheprinciple,hasnotyetratifiedtheprotocol.
Duringnegotiationsinrecentyears,somedevelopedcountries,includingtheUnitedStates,haveexpresseddissatisfactionwiththeprinciple,demandingthatdevelopingcountriesalsocommitthemselvestothebindingtargetsonemissioncuts.
Why,then,don'tsomedevelopingcountriessuchasChina,IndiaandBrazil,alsomajorcarbonemitters,havetocommitthemselvestothelegallybindingtargetsonemissionscuts?
Thereasonisthatthepercapitaemissionsofthosecountriesarefarlessthanthoseofthedevelopedones,andtheyhaveproducedonly"survivalemissions"insteadof"luxuryemissions."
Moreimportantly,thecarbondioxidecurrentlyintheatmospherewasmostlyproducedduringtheindustrializationprocessofthedevelopedcountries.
Itisworthnotingthatcarbondioxide,theprimarygreenhousegas,hasanatmosphericlifetimeofbetween50to200years.
ThatmeansthatthecarbondioxidedischargedbyWesterncountriesduringtheIndustrialRevolutionperiodsome200yearsagostillremainsintheatmosphere.
Astheconventionsaid:"Thelargestshareofhistoricalandcurrentglobalemissionsofgreenhousegaseshasoriginatedindevelopedcountries,"and"percapitaemissionsindevelopingcountriesarestillrelativelylow."