the investigation future evolution of glacier and ... · an underestimate of the rates of glacier...

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The First Workshop of the Chinese-Norwegian 'Third Pole-Arctic Center’, 2019.10.7, Bergen The investigation future evolution of glacier and hydrological impacts by an integrated atmosphere- glacier-hydrological modelling system: case study of a Norwegian glacier Lu Li 1 (李璐), Trude Eidhammer 2 , Adam Booth 4 , Bhuwan Bhatt 3 , Atle Nesje 1,3 and Stefan Sobolowski 1 1. NORCE Norwegian Research Centre, Bjerknes Center for Climate Research, Bergen, Norway 2. National Center for Atmospheric Research (NCAR), Boulder, USA 3. University of Bergen, Bergen, Norway 4. University of Leeds, UK

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Page 1: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

TheFirstWorkshopoftheChinese-Norwegian'ThirdPole-ArcticCenter’,2019.10.7,Bergen

Theinvestigationfutureevolutionofglacierandhydrologicalimpactsbyanintegratedatmosphere-glacier-hydrologicalmodelling system:casestudyof

aNorwegianglacier

LuLi1(李李璐璐),Trude Eidhammer2,AdamBooth4,Bhuwan Bhatt3,AtleNesje1,3 andStefanSobolowski1

1. NORCENorwegianResearchCentre,Bjerknes CenterforClimateResearch,Bergen,Norway

2. NationalCenterforAtmosphericResearch(NCAR),Boulder,USA3. UniversityofBergen,Bergen,Norway4. UniversityofLeeds,UK

Page 2: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

• Glacierscover∼10%oftheEarth’slandsurface;• Watersupplyfordomesticandindustrial

consumption,irrigationandhydropower;• Glaciersareshrinkingrapidly,leadingto

cascadingimpactsondownstreamsystem.

Background

Westilldon’tfullyunderstandthesechangesandhowtheywillpanoutinthefuture.

ü Observationsscarcity;ü topographiccomplexity;ü Toocoarseatmosphericmodels;ü Regional‘atmosphere-only’models; Globalglacierlengths(Roeetal.,2016,Naturegeosciences)

Glacier

Reservoir

Page 3: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

Hypothesis:missingfeedbacksandresolutiondependentprocessesresultinanunderestimateoftheratesofglacierchangeandattendanthydrologicalimpacts.

Anintegratedcoupled-modellingapproachisneededinordertofullyassesstheeffectsofawarmingclimateonglaciersandtheirhydrologicalimpacts.

Glacier

LinLout Hsen Hlat

P

SinSout

Land/hydro

Albedo

Layer1(T,liquid,grain,density)

Tair

Ts

MeltRefreezing

… Hcon

Atmosphere

Layers

GSubsurface

Rm

Ex

Underground

Q

Groundsurface

IR

ET

Finse

Blåisen

Midtdals- breen

Rembesdalsskåka ’Tipping point’ ELA ~1800 m a.s.l.

1670

1670

1670

1670

1670 = Steady-state ELA

norgeskart.no

Oslo Bergen

Trondheim

Maingoal

Page 4: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

WRF-HydroSystem

Model Chain

Meteorological forcing (Observations or model)

https://www.ral.ucar.edu/projects/wrf_hydro

One-waycoupling(canbetwo-waywithWRF(WeatherResearchandForecastingModel))

Page 5: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

CouplingofCrocussnowmodelinWRF-Hydromodelsystem(WRF-Hydro/Glacier)

LandsurfaceofWRF-Hydromodelsystem

Crocussnowmodel

• One-dimensionalmultilayersnowscheme;• Variablesnowlayers(upto50);• Detailedphysicaldescriptionofsnowproperties.

Page 6: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

WRF-Hydro/GlacierModelling

WRF1kmrunsasmeteorological forcinginput

WRF-Hydro/Glacierrunsat100mgrid

CrocusSnowModeloverGlacier grids

• Drivenby6hourlyERA-Interim

Page 7: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

Temperatureisaccurate(left),details inprecipitation(right)aremissinginSeNorge2;WRFismore‘true’inaphysicalsense

WRF

Observation(SeNorge2)

mm/drainfallTemperature

Meandaily(1995)

(Courtesy:Bhuwan Bhatt)

Topography

Page 8: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

General pattern in agreement, although some issues with absolute values.

More faith in GPR depths over the thin snow, more faith in the model over thicker snow.(Courtesy:Adam)

Snowdepth:Modelvs.Radarsurvey

Page 9: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

MassbalanceRembesdalskåka: CROCUSvs.NoahMP

CROCUSNoahMP

ModelObservations

(Courtesy:Trude)

Page 10: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

1995 2055

• GlacierwillberetreatinginHardangerjøkulen during2005– 2055takenfrom(Åkesson,2018)

• Hindcast:1995-2005andFuture:2055-2065• FuturesimulationbyPGWmethod.

Glacier(icethickness)initialization

Page 11: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

The results show a change ~ -2 m/yr of glacier mass balance in the future(2055-2065) compared with the historical period (1995-2005).

FuturemassbalancechangesofRembesdalskaka

NVE-Obs Ba: -0.58Hindcast Ba: 0.04Future Ba: -1.98

2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065

(massbalanceobservationfromNVE)

Page 12: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

Futurechangeofrunoff

• FuturerunoffareprojectedtoincreaseinSpring andAutumn;

• Summerrunoffwillincreaseintheheavilyglacierized anddecreaseinthenon- /little-glacierized basins.

heavilyglacierized(60%)

Future(2055-2065)vs.Hindcast (1995-2005)

littleglacierized

Page 13: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

• Modelprecipitationshowedamorereasonableresultthangriddedobservationdata;

• TheintegratedmodelwithCROCUSimprovesthemassbalanceresultscomparingwithNoahMP;

• InHardangerjøkulen,futurewarmingclimate(2055-2065,RCP8.5)willconductachange~-2m/yr massbalancecomparingwithhistoricalperiod(1995-2005),whichwillresultinrunoffincreaseinbothSpringandAutumn,whilemoremixedchangesinsummer,i.e.,runoff decreaseinthelittle/noglacierized basinwhileincreaseintheheavilyglacierized (60%)basin.

Forward:• ComparetheoutputsfromWRF-Hydro/GlaciersimulationsandHBVmodel

withglacierparameterization.• ModelcanbeappliedtootherglaciersinNorwayandbeyond(i.e.,Himalaya,

TP).

Summary

Page 14: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

Midtdalsbreentongue

Ellen

2.6m

Kickoffmeeting,Bergen, Nov.15-16, 2016

Finalworkshop,Rosendal,May27-29,2019Middalselvi streamflow

Lu andStefan

EllenAdam

GPRsurvey

GPRsurvey

Atle

AcknowledgementstothewholeEvoGlac teamandsupportsfromLATICEgroup,NVEandHiddenCost project!LuLi:[email protected]

Page 15: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

Catchments

Catchments

Reservoirs

• 10catchments• DEM10mtopography• Dischargedatamostmissedafter

1980th.

Page 16: The investigation future evolution of glacier and ... · an underestimate of the rates of glacier change and attendant hydrological impacts. An integrated coupled-modelling approach

• Investigateconvective-scaleevents,relatedprocessesandtheirchanges

• Provideacollectivemulti-modelensembleassessmentandintercomparison

• Shapeacoherentandrobustassessmentoftheconsequencesofclimatechangeonconvectivephenomenaimpactsatlocaltoregionalscales

WCRP-CORDEXFlagshipPilotStudyonConvection

ByStefanSobolowski,ErikaCoppolaandTheFPSConvectionteam

(Courtesy:StefanSobolowski)

TheFPSConvectionlaunchedFall2016(31participatinginstitutes),Fall2019firstfuturechangeensemblescompleted