climatechangeinmtnregionssteenburgh/classes/6250/...uncertainties? recent global climate trends...
TRANSCRIPT
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ClimateChangeinMountainousRegions
JimSteenburghDepartmentofAtmosphericSciences
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.
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• 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.