climatechangeinmtnregionssteenburgh/classes/6250/...uncertainties? recent global climate trends...

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ClimateChangeinMountainousRegions

JimSteenburghDepartmentofAtmosphericSciences

UniversityofUtahjim.steenburgh@utah.edu

801-581-8727488INSCC(InSuite488)

LearningObjectives• Afterthisclassyoushould:– Haveabasicunderstandingofrecentglobalandregionalclimatetrendsandtheirdrivers

– Recognizethesignificanceofclimatechangeformountainousregions

– Beabletodistinguishbetweenclimatevariabilityandchangeandhowtheyaffectandcomplicatetheinterpretationoflong-termtrendsandweatherevents

– HaveabasicunderstandingofhowfutureclimatechangewillaffectsnowoverthewesternUSandUtah

Discussion

Whataspectsofourunderstandingofclimatechangedoweknowwithmediumorhigh

confidence?

Inwhatareasdowestillhavelargeuncertainties?

RecentGlobalClimateTrends

“Warmingoftheclimatesystemisunequivocal,andsincethe1950s,manyoftheobservedchangesareunprecedentedoverdecadestomillennia.Theatmosphereandoceanhave

warmed,theamountsofsnowandicehavediminished,[and]sealevelhasrisen.”– IPCC(2013)

NOAA/NCEI

RecentTemperatureTrends ALongerViewAnomaliesrelativeto1881–1980mean

Masson–Delmotte etal.(2013,IPCCAR5)

MedievalClimateAnomaly

LittleIceAge

“ThemeanNHtemperatureofthelast30or50yearsverylikelyexceededanyprevious30- or50-yearmeanduringthepast800years…Confidenceislowerinthisfindingpriorto1200,becausetheevidenceislessreliableandtherearefewerindependentlinesofevidence.”

– IPCC(2013)

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AnEvenLongerView

Source:NRC(2002),Alley(2000),https://www.ncdc.noaa.gov/paleo/pubs/alley2000/alley2000.html

ArcticSeaIce

Source:http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/http://nsidc.org/arcticseaicenews/2015/09/2015_arctic-minimum/

Arcticvs.Antarctica

Source:https://nsidc.org/data/seaice_index/

NearM

inim

umExten

tNearM

axim

umExten

t

LandIce(Antarctica/Greenland)

Source:Gracesatellite,http://climate.nasa.gov/vital-signs/land-ice/

365Gigatones =1mmsealevelrise

GreenlandMassBalance

SMB=SurfaceMassBalanceD=IceDischarge

“Thetotal2000–2008mass…isequallysplitbetweensurfaceprocesses(runoffandprecipitation)andicedynamics.Withoutthemoderatingeffectsofincreasedsnowfallandrefreezing,post-1996Greenlandicesheetmasslosseswouldhavebeen100%higher.”

Source:vandenBroeke (2009,Science)

Glaciers

Source:http://www.grid.unep.ch/glaciers/pdfs/glaciers.pdf,USGSSouthCascadeGlacier,WA

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Glaciers

Source:https://news.agu.org/press-release/alaska-glaciers-make-large-contributions-to-global-sea-level-rise/

SeaLevelRise

Source:http://sealevel.colorado.edu/

Risesince1870=195mm(7.5inches)Rateofriseisincreasing

Currentrate=3.3mm/yr =1.3in/decade

SeaLevelRise

Source:http://sealevel.colorado.edu/

Contributors(1993–2010)*OceanThermalExpansion=1.1mm/yr

GlacialMassLoss=.76mm/yrGreenlandIceSheet=.33mm/yrAntarcticIceSheet=.27mm/yrLandWaterStorage=.38mm/yr

*Middleofestimaterangenoted

AttributionofRecentClimateChange

Source:2005CoxRadioInteractive&CoxRadio,Inc.

GreenhouseGasConcentrations

• CO2morethan35%higherthanpre-industrial– Halfofincreasesincemid1970s– Verylikelyexceedshighestnaturalconcentrationsoveratleastthelastseveralhundredthousandyears

• IncreasesinothergreenhousegasestooSource:Forsteretal.(2007),https://www.esrl.noaa.gov/gmd/ccgg/trends/

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KnownClimateForcings

Source:Myhre etal.(2013)

ClimateModelSensitivity

Source:Steenburgh (2014),adaptedfromKnutsonetal.(2013)

ClimateFingerprinting

Source:http://www.globalchange.gov/sites/globalchange/files/sap1-1-draft3-all.pdf

RecentEstimates

Source:HuberandKnutti (2012)

RecentEstimates

Source:http://www.skepticalscience.com/a-comprehensive-review-of-the-causes-of-global-warming.html

KeyRemainingUncertainties• Aerosol-radiationandaerosol-cloud-radiationinteractions

• Futureclimateforcings– Trajectoryofanthropogenicforcings likeGHGconcentrations,

aerosols,dust,etc.

• Sensitivityofclimatetothoseforcings (stillawiderangeofpossibleoutcomes)

• Regionalclimateandimpacts

• Shiftsinweatherandclimateextremes– Waterisoftentheagentthatdeliversclimatechangeimpacts

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ClimateChangeinMountainousRegions

Discussion

Whatmakesmountainsimportantforthestudyofclimatechangeanditsimpacts?

Whataresomeofthepossibleconsequencesofclimatechangeinmountainousregions?

SignificanceofMountains

“Mountainsareimportantsourcesofwater,energy,minerals,forestandagriculturalproductsandareasofrecreation.Theyarestorehousesofbiologicaldiversity,hometoendangered

speciesandanessentialpartoftheglobalecosystem.”– UN(1992)

Source:Beniston (2003)

SignificanceofMountains• Mountainscoverabout25%ofcontinentalsurfaces– Mountains,Hills,andPlateauscover46%

• 26%ofworld’spopulationlivesinmountainsortheirfoothills

• 40%ofworld’spopulationlivesinwatershedsoriginatinginmountainousregions

• Mountain-basedresourcesindirectlyprovidesustenanceforoverhalftheworld’spopulation

Source:Meybeck etal.(2001),Beniston (2003)

SignificanceofMountains

• Mountainsareuniqueareasfordetectingclimatechangeandassessingclimate-relatedimpacts– Vegetation,snow,ice,andhydrologyvaryrapidlywithelevationandover

shortdistances– Mountainshavehighbiodiversitywithlargeecosystemgradients(ecotones)– Mountainsareoftenclimateandecosystemislandscomparedtothe

surroundingplains

Source:Beniston (2003)

SpecificAreasofConcern• Water,snow,andice

– Amount,timing,andseasonalityofprecipitationandsnowfall– Depthanddurationoftheseasonalsnowpack– Changesin“permanent”snowandice– Amount,timingandseasonalityofrunoff– Extremeeventsandhazardssuchasfloods,landslides,avalanches,etc.

• Vegetation,forests,andbiodiversity– Vulnerabilitytoclimate-changethresholds– Impactstonaturalandhuman-managedecosystemsandagriculture

• Health– Shiftsinvector-bornediseases(e.g.,Malaria)

• Tourism– Skiing,hiking,etc.

Source:Beniston (2003)

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TheWesternUS

Discussion

Howdoyouthinkclimatechangewillaffecttheaforementionedareasofconcerninthe

westernUS?

Howwillchangesvaryregionallyandwithaspectandelevation?

USTemperatureTrends

Source:http://nca2014.globalchange.gov/highlights/report-findings/our-changing-climate

Note:Basedlargelyonlow-elevationstations&doesn’tcapturethesmall-scalevariability

Utah

1993

2011

20121934

NOAA/NCEI

WesternSnowpackTrends

SWE/PFractionofwinter

precipitationretainedinthesnowpackonApril1st

Source:Pierceetal.(2008)

WesternStreamflow Trends

Timingofspring-pulseonset Dateofcenterofmassofannualflow(Inset:Non-snowmelt-dominatedguages)

Source:Stewartetal.(2005)

“Theimmediateforcings forthespatiallycoherentpartsoftheyear-to-yearfluctuationsandlonger-termtrendsofstreamflow timinghavebeenhigherwinterandspringtemperatures.Althoughthesetemperaturechangesarepartlycontrolledbythe[Pacificdecadaloscillation

(PDO)],aseparateandsignificantpartofthevarianceisassociatedwithaspringtimewarmingtrendthatspansthePDOphases.”

– Stewartetal.(2005)

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Weather/ClimateVariabilityvs.Change

“Weatherismood,climateispersonality”– MarshallShepherd

Source:http://news.uga.edu

ATaleofTwoSeasons

“Big”Year “Bad”Year

WY2015:West

“ThisIstheNewNormal”- CAGov.JerryBrown

Source:NRCS

WY2017:West

“Thisdroughtemergencyisover,butthenextdroughtcouldbearoundthecorner.Conservationmustremainawayoflife.”

- CAGov.JerryBrown

Source:NRCS

Discussion

Whatisthenewnormal?TheFuture

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FutureProjections

Source:IAMCRCPDatabase,Steenburgh (2014,adaptedfromKnutti andSedlacek 2012)

WintertimeTemperatureChange

Source:Steenburgh (2014,adaptedfromDiffenbaugh andGiorgi2012),CourtStrong

1986–2005to2080-2099High-GrowthScenario

You AreHere

WintertimePrecipitationChange

1986–2005to2080-2099High-GrowthScenario

You AreHere

Source:Steenburgh (2014,adaptedfromDiffenbaugh andGiorgi2012),CourtStrong

Discussion

Whatdoyouthinkthismeansforthefutureofsnowandskiinginthewest?

SnowfallVulnerability

Source:Steenburgh (2014,adaptedfromJones2010)

Vulnerabilitygreatest@lowerelevations

Upperelevationslessvulnerable

(butnotimmune)

DownscaledProjections

PierceandCayan (2013),HighGrowthScenario

Changefrom

1976–20

05

SFE=Snowfallwaterequivalent

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DownscaledProjections

PierceandCayan (2013),HighGrowthScenario

Changefrom

1976–20

05

SWE=Waterequivalentofsnowpack

SnowfallProjections

Luteetal.(2015)

SnowfallWaterEquivalent(SFE)1950–2005to2040–2069HighGrowthScenario

%ChangeSFE

%ChangeSnowDays

%ChangeBigStorms

ColderStationsWarmerStations

Summary• Warmingoftheclimatesystemisunequivocal

• Multiplelinesofevidencesupporttheconclusionthatmost(perhapsall)oftherecentwarmingishumancaused

• Futurewarmingdependsonfutureemissionsandotherhumaninfluencesandthesensitivityoftheclimatesystem

• Impactsonmountainousregionsvaryregionallyandwithelevationsandextendtopeopleinnon-mountaonous regions

• Thecompetitiveadvantagesofhighelevationresortswilllikelyincreaseintimeduetotheunevenlossofsnowandsnowpackwithaltitude

References• Alley,R.B.,2000:TheYoungerDryas coldintervalasviewedfromcentralGreenland.Quat.Sci.Rev.,19,213–226.

• Beniston,M.,2003:Climatechangeinmountainregions:Areviewofpossibleimpacts.ClimaticChange,59,5–31.

• Diffenbaugh,N.S.,andF.Giorgi,2012:ClimatechangehotspotsintheCMIP5globalclimatemodelensemble.ClimaticChange,114,813–822.

• Forster,P.,andCoauthors,2007:Changesinatmosphericconstituentsandinradiativeforcing.ClimateChange2007:ThePhysicalScienceBasis.Solomon,S.,D.Qin,M.Manning,Z.Chen,M.Marquis,K.B.Averyt,M.Tignor andH.L.Miller,eds.CambridgeUniversityPress,Cambridge,UnitedKingdomandNewYork,NY,USA.

• Huber,M.,andR.Knutti,2012:AnthropogenicandnaturalwarminginferredfromchangesinEarth’senergybalance.NatureGeoscience,5,31–36.

• Jones,L.P.,2010:AssessingthesensitivityofWasatchsnowfalltotemperaturevariations.M.S.Thesis,UniversityofUtah.

• Knutson,T.R.,F.Zheng,andA.T.Wittenberg,2013:Multimodel assessmentofregionalsurfacetemperaturetrends:CMIP3andCMIP5twentiethcenturysimulations.J.Climate,26,8709–8743.

• Knutti,R.,andJ.Sedlacek,2012:RobustnessanduncertaintiesinthenewCMIP5climatemodelprojections.NatureClimateChange,3,369–373.

• Lute,A.C.,J.T.Abatzoglou,andK.C.Hegewisch,2015:Projectedchangesinsnowfallextremesandinterannual variabilityofsnowfallinthewesternUnitedStates.WaterResourcesResearch,51,960–972.

References• Masson-Delmotte,V.,andCoauthors,2013:Informationfrompaleoclimate archives.ClimateChange2013:ThePhysicalScienceBasis.Stocker,T.F.,

D.Qin,G.-K.Plattner,M.Tignor,S.K.Allen,J.Boschung,A.Nauels,Y.Xia,V.Bex andP.M.Midgley,Eds.CambridgeUniversityPress,Cambridge,UnitedKingdomandNewYork,NY,USA.

• Meybeck,M.,P.Green,andC.Vorosmarty,2001:Anewtypologyformountainsandotherreliefclasses:Anapplicationtoglobalcontinentalwaterresourcesandpopulationdistribution.MountainResearchandDevelopment,21,34–45.

• Myhre,G.,andCoauthors,2013:Anthropogenicandnaturalradiativeforcing.ClimateChange2013:ThePhysicalScienceBasis.Stocker,T.F.,D.Qin,G.-K.Plattner,M.Tignor,S.K.Allen,J.Boschung,A.Nauels,Y.Xia,V.Bex andP.M.Midgley,Eds.CambridgeUniversityPress,Cambridge,UnitedKingdomandNewYork,NY,USA.

• Pierce,D.W.,andD.R.Cayan,2013:Theunevenresponseofdifferentsnowmeasurestohuman-inducedclimatewarming.J.Climate,26,4148–4167.

• Pierce,D.W.,andCoauthors,2008:AttributionofdecliningwesternU.S.snowpacktohumaneffects.J.Climate,21,6425–6444.

• Steenburgh,J.,2014:SecretsoftheGreatestSnowonEarth.UtahStateUniversityPress,186pp.

• Stewart,I.T.,D.R.Cayan,andM.D.Dettinger,2005:Changestowardearlierstreamflow timingacrosswesternNorthAmerica.J.Climate,18,1136–1155.

• vandenBroeke,M.R.,J.L.Bamber,J.Ettema,E.Rignot,E.J.O.Schrama,W.J.vandeBerg,E.vanMeijgaard,I.Velicogna,andB.Wouters,2009:PartitioningrecentGreenlandmassloss,Science,326,984–986.