TristanL’Ecuyer
Contributors: Norm Wood, Jen Kay, Kristof van
Tricht, David Henderson, Alex
Matus,YunHang,ElinMcIlhattan
Radar+LidarCloudMask
2006 •  R03RO
1.
2016 •  R05
2.
2016 •  R04R05
3.
2009 •  R04
4.
2009 •  R04
5.
2006 •  R03RO
6.
Clouds – CloudSat CPR + MODIS optical depth
Sub-visual Cirrus – CALIPSO (5 km Cloud Layer Product)
Stratus/mixed-phase – CALIPSO (identification) + MODIS
(microphysical properties)
Aerosol – CALIPSO (5 km Aerosol Layer Product)
Precipitation – explicit rainfall DSD and CloudSat 2CPRECIP-COLUMN (identification/LWP)
Temperature & Humidity – ECMWF/AIRS (in progress)
CloudSat Radar Reflectivity (dBZ)
Multi-SpectralCloudMask
NetHeating(Kd-1)
CALIPSO532nm
Backscatter
LongwaveHeating(Kd-1)
MODIS11μm
13juin2016
ShortwaveHeating(Kd-1)
L’Ecuyeretal.,J.Geophys.Res.(2008)
LW
NET
SW
13 juin 2016
CALIPSO/CloudSat 10 Year Assessment Workshop
4
Hartmannetal(1992)
Hartmannetal(1992)
2B-FLXHR-LIDAR
2B-FLXHR-LIDAR
13 juin 2016
CALIPSO/CloudSat 10 Year Assessment Workshop
5
LW
SW
NET
13 juin 2016
6
CloudImpactonAtmosphericHeating
TOACRE
HangandL’Ecuyer,2016,inpreparation
SurfaceCRE
13juin2016
Also:Stephensetal,J.Climate(2012)
CALIPSO/CloudSat10YearAssessmentWorkshop
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AnnualMeanRadiative
StandardDeviation
dT
dt
CloudFraction
CloudFraction
CRH(DJF)
CRH(JJA)
Haynesetal.,Geophys.Res.Letters(2013)
13 juin 2016
CALIPSO/CloudSat 10 Year Assessment Workshop
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Matusetal.,2016,inpreparation
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
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PHOTOGRAPH BY PAUL NICKLEN, National Geographic
September2005
September2006
September2007
!
13juin2016
30 Wm-2 over 3 months
is enough energy to
meltabout0.3mofsea
ice or warm the ocean
mixedlayerby2.5K.
Kayetal.,Geophys.Res.Letters(2008)
!
On average, more than 40% of the clouds over the
Greenland Ice Sheet contain super-cooled liquid water
(70%insummer,25%inwinter).
↓
↓
↑
↑
4
↓
R sfc = FLW
+ FSW
− FLW
− FSW
≈ (ε atm −1)σTsfc
+ (1 − α )FSW
SWFlux
Clear-sky
Cloudy-sky
LWFlux
Highα
Overbrightsurfaces,enhancedεatmisthe
dominantcloudeffect
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
13
↓
↓
↑
↑
4
↓
R sfc = FLW
+ FSW
− FLW
− FSW
≈ (ε atm −1)σTsfc
+ (1 − α )FSW
SWFlux
Clear-sky
Cloudy-sky
LWFlux
Highα
Thepresenceofsuper-cooledliquidenhancesthe
cloudeffectonεatm
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
14
!  Cloudsenhancethenetsurface
radiationontheicesheetbyan
average of nearly 30 ± 6 Wm-2
relativetoclearconditions.
!  Unfrozen
liquid
droplets
account for HALF of this
forcing.
!  This is enough energy to melt
upto90Gtoficeeachyear.
!  Surfacemodelingsuggeststhat
thiseffectresultsinabout25Gt
of additional runoff each year
after warming and sublimation
areaccountedfor.
13juin2016
vanTrichtetal.,NatureComm.(2016)
CALIPSO/CloudSat10YearAssessmentWorkshop
15
LCCFREQUENCY
?
DOWNWELLINGLWRADIATION
Greenlandistoo
coldinCESM.
JAN
FEB
13juin2016
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
CALIPSO/CloudSat10YearAssessmentWorkshop
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PRECIPITATIONFREQUENCYOFARCTIC
LIQUIDCONTAININGCLOUDS
~40%
McIlhattanetal.,inpreparation
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
17
Clear-sky!
13 juin 2016
Cloudy-sky!
ADRE(Wm-2)
Clear
sky
Cloudy
sky
All-sky
Land
-2.2
-0.9
-1.5
Ocean
-2.6
-1.5
-2.0
Global
-2.6
±0.6
-1.4
±0.7
-1.9
±0.6
CALIPSO/CloudSat 10 Year Assessment Workshop
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a) Ocean-only DRE (Wm-2)!
FLXHR-LIDAR!
CESM-CAM5!
CESM-CAM5!
FLXHR-LIDAR!
b) Sample size!
FL
AR
-LID
R
H
X
"
Cloud fraction (%)!
13 juin 2016
Matusetal.,J.Climate(2015)
19
!
After10yearsinorbit,CloudSatandCALIPSOareshedding
newlightontheclassicalproblemofestablishingtheroleof
cloudsandaerosolsintheEarth’sradiationbudget.
!
Estimates of cloud radiative forcing, its vertical structure,
andtherelativecontributionsofindividualcloudtypesneed
toberevisedinlightofthesenewactiveobservations.
!
Mixed-phase clouds exert a strong impact on mass balance
of the Greenland Ice Sheet that appears to be underrepresentedinmodels.
!
CloudSatandCALIPSOprovideinsightsintotheinfluenceof
clouds on aerosol direct radiative effects (ADRE) and have
identiyfied a connection between model ADRE and cloud
biases.
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
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!
!
!
!
!
!
Kay, J., T. S. L'Ecuyer, G. L. Stephens, A. Gettelman, and C. O'Dell, 2008. The
contribution of cloud and radiation anomalies to the 2007 Arctic sea ice extent
minimum,Geophys.Res.Letters35,doi:10.1029/2008GL033451.
vanTricht,K.,S.Lhermitte,J.T.M.Lenaerts,I.V.Gorodetskaya,T.L’Ecuyer,B.Noel,
M. R. van den Broeke, D. D.Turner, and N. P. M. van Lipzig, 2015:Clouds enhance
Greenlandicesheetmassloss,NatureComm.7,doi:10.1038/ncomms10266.
Henderson, D. S., T. L'Ecuyer, G. Stephens, P. Partain, and M. Sekiguchi, 2013: A
multi-sensor perspective on the radiative impacts of clouds and aerosols, J. Appl.
Meteor.andClimatol.52,853-871.
Haynes, J. M., T. H. Vonder Haar, T. L'Ecuyer, and D. Henderson, 2013. Radiative
heatingcharacteristicsofEarth'scloudyatmospherefromverticallyresolvedactive
sensors,Geophys.Res.Letters40,doi:10.1002/grl.50145.
Matus,A.,T.S.L’Ecuyer,J.E.Kay,J.-F.Lamarque,andC.Hannay,2015:Theroleof
clouds in modulating global aerosol direct radiative effects in spaceborne active
observationsandtheCommunityEarthSystemModel,J.Climate28,2986-3003.
L’Ecuyer,T.S.,N.Wood,T.Haladay,andG.L.Stephens,2008.Theimpactofclouds
onatmosphericheatingbasedontheR04CloudSatfluxesandheatingratedataset,
J.Geophys.Res.113,doi:10.1029/2008JD009951.
13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
21
SUMMIT,GREENLAND
≈3km
13juin2016
La0tude:72.58°N
Longitude:38.48°W
Eleva0on:3216m
CALIPSO/CloudSat10YearAssessmentWorkshop
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13juin2016
CALIPSO/CloudSat10YearAssessmentWorkshop
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