Arctic Regional Climate Modelling: GEM-Arctic, the DGF...
Transcript of Arctic Regional Climate Modelling: GEM-Arctic, the DGF...
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Arctic Regional Climate Modelling:Arctic Regional Climate Modelling:GEMGEM--Arctic, the DGF Process and Arctic, the DGF Process and
CloudSat CloudSat –– CALIPSO New Perspective CALIPSO New Perspective
JJ--P Blanchet, E. Girard, C. Jones, P Blanchet, E. Girard, C. Jones, P. P. GrenierGrenier, R. Munoz, R. Munoz--Alpizar, P. Du, C. Stefanof, A. Stefanof, D. Alpizar, P. Du, C. Stefanof, A. Stefanof, D. SimjanovskiSimjanovski
University of Quebec at Montreal (UQAM)University of Quebec at Montreal (UQAM)
with collaboration fromwith collaboration from
G. Stephens, D. Winker , C. G. Stephens, D. Winker , C. TrepteTrepte, J. , J. PelonPelon, J. Jiang, E. , J. Jiang, E. FetzerFetzerCloudSat CloudSat –– CALIPSO CALIPSO –– AURA AURA –– AIRS TeamsAIRS Teams
Towards a Polar Snowfall Hydrology Mission: Towards a Polar Snowfall Hydrology Mission: The Science and the GapsThe Science and the Gaps
2626--28 June 200728 June 2007Montreal, Quebec Montreal, Quebec
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ObjectivesObjectives
1.1. Summarize the development of the new Summarize the development of the new GEM GEM –– ClimClim Canadian Regional Climate Canadian Regional Climate ModelModel
2.2. DehydrationDehydration--Greenhouse Feedback (DGF)Greenhouse Feedback (DGF)an indirect effect of aerosols on cloud and an indirect effect of aerosols on cloud and precipitation and climate in the Arctic.precipitation and climate in the Arctic.
3.3. New results from New results from CloudSatCloudSat--CALIPSOCALIPSO
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CRCM CRCM -- ArcticArctic
Two ModelsTwo Models (dynamic kernels) are used:(dynamic kernels) are used:
NARCMNARCM = CRCM (MC2) + CAM aerosols= CRCM (MC2) + CAM aerosolsStatus: Mature with 6 years of experimentsStatus: Mature with 6 years of experimentsStructure: Scalar model (very slow !!!)Structure: Scalar model (very slow !!!)
GEMGEM--CAMCAM = CRCM (GEM) + CAM aerosols= CRCM (GEM) + CAM aerosolsStatus: In development from forecast modelStatus: In development from forecast modelStructure: Parallelised modelStructure: Parallelised model
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The Canadian Regional Climate Modellingand Diagnostics (CRCMD) Network
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GEM can be run in a variety of configurations
● Potential for a common modelling framework for the development and application of both global & regional climatemodels
● Joint weather forecast, climate and cloud resolving domains
● Applicable to any regions on a wide range of scales
● One application is the Arctic processes and climate studies
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Simulated Annual cycle of 2-metre temperature at 3 distinctly different climatic locations around the globe.
Ref.: Zav Kothavala, Colin Jones, Katja Winger, Bernard Dugas & Ayrton Zadra
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BondvilleckMAGS GAPP BALTEX GAME
LBA LA PLATA CEOP Observation Site
MDB
AMMA
Transferability of GEM-LAM has been assessed through participation in the GEWEX-CEOP ICTS transferability study.
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We have made some tests of GEM-LAM over North Americaon a common domain at 0.45º, 0.3º and 0.15º resolution
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Barrow: Native domain freq. distribution (Precipitation)
Ref.: Zav Kothavala, Colin Jones, Katja Winger, Bernard Dugas & Ayrton Zadra
Winter Summer
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GEM Evaluation vs SHEABARef.: D. Simjanovski and C. Jones
PRECIPITABLE_WATER
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NARCM: Aerosol SizeNARCM: Aerosol Size--Specie ResolvedSpecie ResolvedS ectiona l S ize R epresen ta tion
A eroso l R ad ius [μm ]
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• Flexible model structure• Multi-components Simulations• Physically based size distribution• Numeric diffusion for particle growth• Computational intensive (large bin no.)
Gong, Barrie and Blanchet et al. 2003, JGR
Mas
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CanadianAerosol ModuleGong et al (1997, 2003)
DynamicsPhysics
Semi-lagrangiantracer transport
CRCMCanadian Regional Climat Model
Aerosol sourcefunction
Aerosol processes
CAMCanadian Aerosol Module
NARCMNorthern Aerosol Climate Model
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DehydrationDehydration GreenhouseGreenhouse Feedback Feedback DGF DGF -- ProcessProcess
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Sulphur Injection into the ArcticSulphur Injection into the Arctic
AMAP Assessment Report: Arctic Pollution Issues. Arctic Monitoring and Assessment Programme (AMAP), Oslo, Norway. Xii+859 pp
64%
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Noril’skA point source
within the Arctic Circle
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Evidences of Evidences of aerosol alterations in the Arcticaerosol alterations in the Arctic
BiggBigg (1980) observed (1980) observed sulfuric sulfuric acid coatingacid coating on nearly all on nearly all other aerosol particles during other aerosol particles during winterwinter
Boris observed Boris observed reduced ice reduced ice nuclei activitynuclei activity by 100 to by 100 to 10000 fold in crystal counts 10000 fold in crystal counts during anthropogenic Arctic during anthropogenic Arctic haze event.haze event.
New laboratory observationsNew laboratory observations(Bertram and Girard) confirm (Bertram and Girard) confirm the reduced IFN activity of the reduced IFN activity of sulfuric acid coated aerosolssulfuric acid coated aerosols
Reaction on calcium fluorideRef.: Bigg, 1980
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Size (μm)
Tim
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ays)
Cold CloudsCold Clouds Regime (Arctic FallRegime (Arctic Fall--WinterWinter--Spring)Spring)
Ref.: Girard, Blanchet, JAS 2001
Radius (microns)0.01 0.1 1 10
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• Fewer but larger ice crystals• Cooling positive feedback (colder)• Radar: visible• Thin Ice Cloud type 2
Radius (microns)0.01 0.1 1 10
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• Numerous and small ice crystals• Long cloud lifetime (warmer)• Radar: no or weak return• Thin Ice Cloud type 1
20µm 200µm Mas
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Lesserosion
H2SO4shell
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Ice and Snow layers
Two Opposite States: Diamond Dust or Ice Fog
Dehydration-Greenhouse Feedback (DGF)
Less H2O vapour
Acid Aerosols **
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**Low Acid AerosolsHydrophilic
WarmerColder
Reduced Greenhouse
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Clouds forming on acidic ice nuclei precipitate more effectively, dehydrate the air, reduce greenhouse effect and cool the surface
Slow Cooling Process adiabatic cooling and IR lost
Thin Ice Clouds type 1Thin Ice Clouds type 2
Cold Ice and Snow Surface
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AVHRR T 20 yr Summer Temperature Trend NASA/Goddard Space Flight CenterScientific Visualization Studio, Larry Stock, Robert Gerstenbased on data analysis by Joey Comiso (NASA)
Sea ice-albedo feedback (+)
Snow-albedo feedback (+)
A rapidly declining perennial sea ice cover in the Arctic, Geophysical Research Letters, Vol. 29, No. 20, October 2002
http://svs.gsfc.nasa.gov/search/Keyword/Arctic.html
Mean Annual Trend °C / yr
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AVHRR T 20 yr Winter Temperature Trend 1982-2002 NASA/Goddard Space Flight CenterScientific Visualization Studio, Larry Stock, Robert Gersten (2003)
CGCM1/IS92a-Winter
2040-60 minus 1975-95
Mean Annual Trend °C / yr
Raatz, 1991H
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AVHRR T 20 yr Winter Trend near Noril’sk,Russiaemits 2.8Mt SO2/yr at 69°N 88°E in the Arctic Circle
Main flow Acid shadow?
Acid shadow? Acid shadow?
Noril’sk(coldest trend!)
Ref.: NASA Goddard
Mean Annual Trend °C / yr
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AVHRR T 20 yr Autumn Trend near Noril’sk,Russiaemits 2.8Mt SO2/yr at 69°N 88°E in the Arctic Circle
Acid shadow?Noril’sk(cold trend)
Ref.: NASA Goddard
Mean Annual Trend °C / yr
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AVHRR T 20 yr Spring Trend near Noril’sk,Russiaemits 2.8Mt SO2/yr at 69°N 88°E in the Arctic Circle
Noril’sk
Ref.: NASA Goddard
http://svs.gsfc.nasa.gov/search/Keyword/Arctic.html
Mean Annual Trend °C / yr
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WhatWhat do do wewe seesee in the in the ArcticArcticfromfrom CloudSat CloudSat –– CalipsoCalipso ??
Can Can wewe detectdetect DGF type of DGF type of processprocess ??On On whatwhat scalescale ??
Do Do wewe seesee anyany possible possible responseresponse ??
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Typical Winter ConditionsTypical Winter ConditionsJanuary 1, 2007 January 1, 2007 –– CALIPSO + CloudSatCALIPSO + CloudSat
CloudSat
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Case Case StudyStudy: : KyrillKyrill StormStormJanuaryJanuary 18, 200718, 2007
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KyrillKyrill StormStormJanuaryJanuary 19, 200719, 2007
Surface Pressure(black lines mb)
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KyrillKyrill Storm Storm –– System Through ExtensionSystem Through Extension
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AerosolAerosol Simulation Simulation duringduring KyrillKyrill StormStormJanuaryJanuary 1515--21, 200721, 2007
CAM – segmented aerosol model: 12 size bins from 0.005 to 20 µm5 species: sea salt, soil, organics, soot and sulfate
Scale: Log Concentration in kg.m-3
Total Aerosol – 854mb Sulfate Aerosol – 923mb
Horizontal resolution: 45kmModel NARCM
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ViewView fromfrom CalipsoCalipso –– CloudSat CloudSat JanuaryJanuary 19, 200719, 2007
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U.S.A. U.S.A. –– ArcticArctic ComparisonComparison
2007/01/19 08:25:37.4350 UTC 2007/01/19 01:50:03.2330 UTC
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Frequent Arctic Overpass Frequent Arctic Overpass Compact Time Sampling and near 3D Horizon ViewCompact Time Sampling and near 3D Horizon View
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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«« Tour Tour dd’’horizonhorizon »» around the Polearound the PoleJanuary 19, 2007January 19, 2007
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Weather Weather SynopticsSynoptics of of KyrillKyrill StormStormJanuary 16 January 16 –– 29, 200729, 2007
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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Surface Pressure & 500mb HeightSurface Pressure & 500mb Height( ~ Mean Temperature in lowest 5 km)( ~ Mean Temperature in lowest 5 km)
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DGF Process in ActionDGF Process in Action
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EnhencedCold Dome
Airmass
TIC type 2: Cold TIC type 2: Cold LowLow PenetrationPenetration in in thethe ArcticArctic andandSlowlySlowly Lifting Lifting AcidicAcidic AerosolAerosol withwith DGFDGF
IRNET
LSCALE: A 5 to 8 day dehydration- IR cooling process1000 – 3000 km
Radar VisibleLarge Ice Crystals
Higher Precipitation Rate
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Day 1January 18, 2007
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Day 2January 19, 2007
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Day 3January 20, 2007
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Day 4January 21, 2007
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Day 5January 22, 2007
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Day 6January 23, 2007
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Day 7January 24, 2007
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O3
CO2
H2O H2OTrace Gases
Greenhouse Atmospheric Radiation at the groundGreenhouse Atmospheric Radiation at the groundWater Vapour is the Strongest Greenhouse GasWater Vapour is the Strongest Greenhouse Gas
Downward IR spectral radiance (53° zenith angle) using LOWTRAN
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ArcticArctic EquinoxEquinoxJuneJune 21, 200721, 2007
3200 km
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TIC type 1: Cold TIC type 1: Cold LowLow PenetrationPenetration in in thethe ArcticArctic andandSlowlySlowly Lifting Lifting PristinePristine Air Air withoutwithout DGF DGF EffectEffect
L
IR
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Radar TransparentSmall Ice Crystals
Low Precipitation Rate
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Arctic Winter: Thin Ice Clouds Type 1 (pristine) over GreenlandJanuary 19, 2007
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TIC-1
Thin Ice Clouds Thick Ice CloudsMid-latitudesAntarctic
Antarctica Winter: Thin Ice Clouds Type 1 (pristine)July 15, 2006
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Summary: Cloud Types Summary: Cloud Types –– IFN AerosolIFN AerosolJanuary 19, 2007January 19, 2007
Thin Ice Cloud type 2 high [aerosols] (acidic),
large ice crystalsand fast sedimentation
Thin Ice Cloud type 1low [aerosol] (pristine),
small crystalsslow sedimentation
DGF-DeepDGF-PBL
No DGF
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ThinThin IceIce Cloud (TIC) TypesCloud (TIC) Types
TICTIC--11Pristine environmentPristine environment
Active IFN (low acid) Active IFN (low acid) Small ice crystalsSmall ice crystalsWeak sedimentation rateWeak sedimentation rateRandomly orientationRandomly orientationLower IR emissivityLower IR emissivityRadar transparentRadar transparentEx: thin cirrus (pristine)Ex: thin cirrus (pristine)
Ice Ice stratusstratus or ice fogor ice fog
TICTIC--22Anthropogenic effectAnthropogenic effect
Low activity IFN Low activity IFN (high acid content)(high acid content)Large ice crystalsLarge ice crystalsLarge sedimentation rateLarge sedimentation rateHorizontal orientationHorizontal orientationLarger IR emissivityLarger IR emissivityRadar visibleRadar visibleEx: diamond dust (acid)Ex: diamond dust (acid)
deep arctic cirrus deep arctic cirrus (4 (4 -- 10 km deep)10 km deep)
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Two Important Climate Feedbacks Two Important Climate Feedbacks are Interlinked during Arctic Winter :are Interlinked during Arctic Winter :
Vertical :Vertical : Acid aerosols alter thin ice cloud Acid aerosols alter thin ice cloud microphysics, enhancing IR cooling and microphysics, enhancing IR cooling and dehydration dehydration lower temperatureslower temperatures
Horizontal :Horizontal : Lower temperatureLower temperature generates generates APE enhancing midAPE enhancing mid--latitude storms which latitude storms which transport aerosols into the Arctic and further transport aerosols into the Arctic and further cools in the cools in the vertical vertical process.process.
“Arctic Thermal Pumping”
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Temperature Trend: Temperature Trend: Simulation Simulation vsvs ObservationObservation
Hansen, et al (GISS)
70 year observed trend
Ref.: Pavlovic and Blanchet, 2002
SimulationNARCM + Girard - Curry Cloud
NorilskKola
AVHRR 20 year Trend
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CorrelationCorrelation betweenbetweenRelative Relative HumidityHumidity andand
AcidAcid FractionFraction fromfrom AIRS AIRS Data Data andand NARCM NARCM
SimulatedSimulated AerosolsAerosols
Correlation between rw and sulfate ratioin function of temperature
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temperature (oC)
corr
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700 mb850 mb925 mb
Ref.: Grenier, Blanchet and Fetzer (2006)
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Example: ensemble of 12 January Example: ensemble of 12 January Simulations (perturbed Simulations (perturbed –– reference)reference)
[ Aerosol (µg/m3 ] IWC annomaly
Precipitation annomaly IR down at sfc annomaly (W/m2)
Temperature annomaly °C
Ref.: Stefanof A., 2005 (MSc)Girard E. et al, 2006
Dehydration Efficiency
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1900 1920 1940 1960 1980 2000
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Num ber o f Intense W inte r C yc lones pe r YearsNorthern Hem is phere (Lam bert, 1997)
Observed Trend in the Winter StormsObserved Trend in the Winter StormsNorthern HemisphereNorthern Hemisphere
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Model Model StudiesStudiesWe have done We have done several simulationsseveral simulations of this process of this process using the CRCM and CAM models.using the CRCM and CAM models.Results show consistently that Results show consistently that reduction of IFN reduction of IFN activityactivity increase light precipitation, dehydration increase light precipitation, dehydration and cooling efficiencyand cooling efficiency..Efforts are needed to Efforts are needed to improve improve parameterisationparameterisation of of DGF process.DGF process.3D Prognostic precipitation3D Prognostic precipitation fields are requiredfields are requiredCloud resolving simulationsCloud resolving simulations are needed to bridge are needed to bridge scale gaps.scale gaps.Improving the Improving the PBL schemePBL scheme in cold climate is in cold climate is needed needed
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SummarySummaryTwo types of thin ice cloudsTwo types of thin ice clouds can occur depending on IFN can occur depending on IFN activity.activity.
DGF can be driven by DGF can be driven by IR coolingIR cooling (PBL) or deep slow (PBL) or deep slow adiabatic ascendadiabatic ascend in decaying low pressure systems entering in decaying low pressure systems entering the Arctic.the Arctic.
TypeType--2 (acidic) 2 (acidic) IRIR-- cools a deep cools a deep tropospherictropospheric layerlayer in 5in 5--8 8 days over 1000days over 1000--3000 km scale. 3000 km scale.
Colder pole fuel intense stormsColder pole fuel intense storms transporting new aerosols transporting new aerosols into the Arctic.into the Arctic.
CloudSat and CALIPSOCloudSat and CALIPSO reveal the complex interactions reveal the complex interactions between aerosols, clouds, precipitation, radiative cooling and between aerosols, clouds, precipitation, radiative cooling and large scale circulation.large scale circulation.
We are developing new We are developing new atmospheric modelatmospheric model to simulate these to simulate these interactions in climate models. interactions in climate models.
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«« DGF may be the largest DGF may be the largest man mademan made
cloud seeding experiment cloud seeding experiment and and
weather modification in the weather modification in the world .world .»»
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AntarcticaAntarctica EarlyEarly WinterWinterJuneJune 18, 2007 (18, 2007 (lastlast weekweek!)!)