CharacterizingClimateandHumanInfluencesonCoastalMarginCarbonDynamicsUsingIntegratedLand-Ocean

ModelingApproaches

StevenLohrenz(U.MassDartmouth)Wei-JunCai(U.Delaware)HanqinTian(Auburn)

RuoyingHe(N.CarolinaStateU.)Zuo“George”Xue(LouisianaStateU.)

Katja Fennel(Dalhousie)

OCBWorkshop- 2017Acknowledgements:NASA,NSF,NOAA,USGS,EPA

Approach: Coupled Terrestrial-Ocean Models

DynamicLandEcosystemModel(v2.0)usedtoestimatespatialandtemporalpatternsofland-aircarbonfluxesandlateraltransportofwater,carbon,andnitrogen

DLEMterrestrialoutputslinkedtoaphysical-biogeochemicalmodel(SABGOM)tocharacterizecoastalcarbonfluxesandecosystemdynamics

Modelingeffortssupportedbyfieldsurvey-basedandsatellite-basedobservationsofcarbonfluxesandotherbiogeochemicalprocesses

Tianetal.,2010a,b;Tianetal.,2011;Tianetal.,2012;Zhangetal.,2012;Taoetal.,2014;Renetal.,2015;Tianetal.,2015

Hoffmanetal.,Ann.Rev.,2011;Fenneletal.,2011,2013

HyunandHe(2010);Xueetal.,2013,2016

DynamicLandEcosystemModelResults

CarbonLeachingPatterns -Spatialdistributionofyearlytotalorganiccarbon(TOC)anddissolvedinorganiccarbonleachingintheMARBaveragedduring2001-2010(Tianetal.,GBC,2015)

IncreasingRiverDischarge - ProjectedMississippiriverdischargeoverthe21stcenturyanditsenvironmentalcontrolsunderhighemissionscenario(A2)(Taoetal.,GRL,2014)

IncreasingTrendinDIC- Annualchangesinexportofdissolvedinorganiccarbon(DIC,Tg Cyr1)fromtheMississippiRiverbasintotheGulfofMexicooverthe21stcentury (Renetal.,JGR-B,2015)

CoupledModelSimulations:1904-1910vs.2004-2010• IncreaseinDLEM-simulatedDINexportfrom

MARBfrom1904-1910comparedto2004-2010• Significantincreaseinsimulatedoceanprimary

production,anddecreaseinpCO2 asaresultofincreasedriverinputs

• Oceanmodelalsoprovidesestimateofalong- andcross-shelftransportofdissolvedinorganicnitrogenforthe2004-2010period

Xueetal.,2013,2016

Summary:UnderstandingClimateandHumanImpactsonTerrestrial-CoastalFluxes

• Integratedmodelingapproachescanbeusefulinunderstandinghowclimateandweather-relatedforcinginconjunctionwithchanginghumanactivitycanalterthetransferofwater,carbonandnutrientsthroughvariousterrestrialreservoirsintorivers,estuaries,andcoastaloceanwaters

• Coastalmarginsmaybeparticularlysensitivetosuchchanges,whichcanalterbiogeochemistryofthecoastaloceanandhaveimplicationsforcarbonsequestration,eutrophication,hypoxia,andoceanacidification

• Modelproductscanprovidedecisionsupportforcarbonmanagement,waterquality,andecosystemsustainability