NASA satellite images show how polluted your country is | CNN

New NASA satellite images show how pollution levels have changed in the last decade in ... according to new global NASA satellite maps. NASAsatelliteimages:Whicharethemostpollutedcountriesintheworld?ByMonicaSarkar,CNNUpdated1354GMT(2154HKT)December17,2015 StoryhighlightsNitrogendioxideisamajorpollutantthatcanplayaroleinasthmaandotherrespiratoryillnessesNewNASAmapsshowincreasesinChinaanddecreasesinU.S.andwesternEurope(CNN)TheUnitedStatesandEuropeareamongtheworld'slargestemittersofnitrogendioxide--butbothhavealsoshownthemostdramaticreductionsintheseemissionsbetween2005and2014,accordingtonewglobalNASAsatellitemaps.Nitrogendioxideisayellow-browngasthatisacommonemissionfromcarsandindustrialactivity.Itisamajorrespiratorypollutantinurbansmog.Photos:NASAsatelliteimagesshowchangesinglobalairqualityPhotos:NASAsatelliteimagesshowchangesinglobalairqualityThisglobalmapshowstheaverageconcentrationofnitrogendioxideintheatmospherein2005,asdetectedbytheOzoneMonitoringInstrumentaboardtheAurasatellite.Blueindicatesanobserveddecreaseinnitrogendioxide,andorangeindicatesanobservedincrease.HideCaption1of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThismapshowstheaverageconcentrationofnitrogendioxideinthetroposphere(theatmosphericlayerclosesttothesurfaceofEarth)in2014.HideCaption2of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityAveragenitrogendioxideconcentrationsacrosstheU.S.in2005.TheU.S.andEuropeareamongthelargestemittersofnitrogendioxide.Bothregionsalsoshowedthemostdramaticreductionsbetween2005and2014.HideCaption3of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityAveragenitrogendioxideconcentrationsacrosstheU.S.in2014.HideCaption4of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThistrendmapoftheU.S.showslargedecreasesinnitrogendioxideconcentrations,between20-50%,from2005to2014.Onlydecreasesarehighlightedhere.HideCaption5of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThistrendmapofEuropeshowsthechangeinnitrogendioxideconcentrationsfrom2005to2014.Nitrogendioxidehasdecreasedbyasmuchas50%inwesternEurope.HideCaption6of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThetrendmapoftheMiddleEastshowsthechangesinnitrogendioxideconcentrationsfrom2005to2014.IntheMiddleEast,researcherssuggestthattheincreasednitrogendioxidelevelssince2005inIraq,KuwaitandIranweredowntoeconomicgrowthinthesecountries.ButinSyria,thedecreasesince2011ismostlikelybecauseofthecivilwarwhichbeganinthatyear,andhassinceleftmorethan300,000peopledeadandforced10.6million--nearlyhalfthepopulation--toflee.HideCaption7of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThetrendmapofthePersianGulfshowsthechangeinnitrogendioxideconcentrationsfrom2005to2014.HideCaption8of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThetrendmapofSouthAfricashowsthechangesinnitrogendioxideconcentrationsfrom2005to2014.TheSouthAfricanregionencompassingJohannesburgandPretoriahasthehighestnitrogendioxidelevelsinthesouthernhemisphere,butthemapshowsacomplexsituationplayingoutbetweenthetwocitiesandneighboringpowerplantsandindustrialareas,saytheresearchers.HideCaption9of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityAveragenitrogendioxideconcentrationsinSouthAfricain2014.Accordingtotheresearchers,theJohannesburg-Pretoriametroareasawdecreasesafternewcarswererequiredin2008tohavebetteremissionscontrols.Theheavilyindustrializedareajusteastofthecities,however,showsbothdecreasesandincreases.Thedecreasesmaybeassociatedwithfeweremissionsfromeightlargepowerplantseastofthecitiessincethedecreaseoccursovertheirlocations.However,emissionsincreasesoccurfromvariousotherminingandindustrialactivitiestothesouthandfurthereast.HideCaption10of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThetrendmapofEastAsiashowsthechangesinnitrogendioxideconcentrationsfrom2005to2014.China,theworld'sgrowingmanufacturinghub,sawanincreaseofbetween20-50%innitrogendioxide,muchofitoccurringovertheNorthChinaPlain.ThreemajorChinesemetropolitanareas--Beijing,Shanghai,andthePearlRiverDelta--sawnitrogendioxidereductionsofasmuchas40%.HideCaption11of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThetrendmapforTexasshowsthepercentagechangeinnitrogendioxideconcentrationsfrom2005to2014.HideCaption12of13Photos:NASAsatelliteimagesshowchangesinglobalairqualityThistrendmapforNorthDakotashowsthepercentchangeinnitrogendioxideconcentrationsfrom2005to2014.Toseethedatainfull,visittheNASAwebsite.HideCaption13of13Thelatestimagesshowhowpollutionlevelshavechangedinthelastdecadeinvariousregionsand195citiesacrosstheworld.Butthespaceagencyhasgoneastepfurtherandlookedathowfactorsontheground,suchaslargepowerplants,haveimpactedthefindings.China,theworld'sgrowingmanufacturinghub,sawanincreaseofbetween20-50%innitrogendioxidemuchofitoccurringovertheNorthChinaPlain,adenselypopulatedareathatrunsfromBeijingsouthtoNanjing.Expert:Changes'aren'trandom'ReadMorePhotos:Beijingsmog:What'sitliketobreathetheair?Photos:Beijingsmog:What'sitliketobreathetheair?Thisweek,Beijingissueditsfirstredalertforhazardouspollution,closingschools,restrictingtrafficandshuttingconstructionsites.ResidentstellCNNwhatit'sliketoliveinthesmog-cloakedcity.HideCaption1of6Photos:Beijingsmog:What'sitliketobreathetheair?HideCaption2of6Photos:Beijingsmog:What'sitliketobreathetheair?HideCaption3of6Photos:Beijingsmog:What'sitliketobreathetheair?HideCaption4of6Photos:Beijingsmog:What'sitliketobreathetheair?HideCaption5of6Photos:Beijingsmog:What'sitliketobreathetheair?HideCaption6of6However,threemajorChinesemetropolitanareas--Beijing,Shanghai,andthePearlRiverDelta--sawnitrogendioxidereductionsof40%.OnDecember8,Beijing'scitygovernmentissueditsfirstredalertforpollution,forcingittocloseschoolsandconstructionsitesandrestricttraffic."Thesechangesinairqualitypatternsaren'trandom,"saidBryanDuncan,anatmosphericscientistatNASA'sGoddardSpaceFlightCenterinGreenbelt,Maryland,wholedtheresearch."Whengovernmentsstepinandsaywe'regoingtobuildsomethinghereorwe'regoingtoregulatethispollutant,youseetheimpactinthedata."Exposuretonitrogendioxidecanplayaroleinasthma,bronchialsymptoms,lunginflammationandreducedlungfunction,accordingtotheWorldHealthOrganization.Themajorsourcesofemissionsofthegascausedbyhumanactivityarecombustionprocesses,suchasheating,powergenerationandenginesinvehiclesandships. Nitrogendioxidelevelshavedecreasedfrombetween20-50%intheU.S.andbyasmuchas50%inwesternEurope.Andresearchersputthesechangeslargelydowntotheeffectsofenvironmentalregulationsthatrequiretechnologicalimprovementstoreducepollutionemissionsfromcarsandpowerplants.IntheMiddleEast,researcherssuggestthattheincreasednitrogendioxidelevelssince2005inIraq,KuwaitandIranweredowntoeconomicgrowthinthesecountries.ButinSyria,thedecreasesince2011ismostlikelybecauseofthecivilwar,whichbeganinthatyear,andhassinceleftmorethan300,000peopledeadandforced10.6million--nearlyhalfthepopulation--toflee.OnDecember12,historywasmadeinParisattheCOP21meeting,wheregovernmentministersfrom195countriesagreedtoabidebyalegallybindingagreementtocombatclimatechangeandkeepglobalwarmingbelowtwodegreesCelsius(36degreesFahrenheit).