1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA...
-
Upload
oswin-goodman -
Category
Documents
-
view
213 -
download
0
Transcript of 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA...
![Page 1: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/1.jpg)
1
An initial CALIPSO cloud climatology
ISCCP Anniversary, 23-25 July 2008, New York
Dave WinkerNASA LaRC
![Page 2: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/2.jpg)
2
Merged CALIPSO-CloudSat product now available
CloudSat
Merged
CALIOP
![Page 3: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/3.jpg)
3
CALIPSO vs. GEWEX CA
Cloud cover, height - CALIOP
Cloud temperature– Mid-cloud temperature (from CALIOP height and GMAO)
– Brightness temperature (from CALIOP + IIR)
Optical depth, extinction profile – ‘Thin’ cirrus only, < 3 to 5
– From CALIOP transmittance (good, 4%)
– From CALIOP retrieval (not as good, 96%)
Emissivity – CALIOP + IIR
Ice/Water phase – CALIOP depolarization
LWC/IWC – parameterized from CALIOP extinction
Particle size– Cirrus only – CALIOP + IIR
– CloudSat + CALIOP (overlap regions only)
Available now
Available, but Beta
(near) future
Not available
![Page 4: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/4.jpg)
4
clouds
aerosol
Sampling resolution:
z = 30 m
footprint = 70 m dia.
footprint separation = 335 m
Altitude location error << 30 m
~ 0.02
Cloud detection is weakly dependent on calibration
surface
![Page 5: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/5.jpg)
5
Arctic Stratus, full resolution (30 m, single shots)
600 m
![Page 6: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/6.jpg)
6
Temporal Averaging (high clouds)
one month one season
![Page 7: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/7.jpg)
7
Cloud Fraction Analysis
Merge clouds in 1/3-km and 5-km products– 1/3-km clouds are cleared from 5-km profiles during processing
Use only layers with CAD score 70-102– Layers with CAD = < 70 (especially 0-20) tend to be “spurious”
> Affects cloud fraction at the 1% level
– 101 = thin polar cirrus originally classified as aerosol, reclassified based on depolarization
– 102 = cloud dominated by horizontally oriented ice crystals
Reclassify “aerosol” over Antarctic plateau as cloud– Increases Antarctic cloud fraction by ~ 5%
Reject PSCs mistakenly classified as tropospheric cloud– Ambiguous GMAO tropopause results in misclassifications
![Page 8: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/8.jpg)
8
Total Cloud Cover
JJA
78.8%
DJF
76.5%
JJA
63.5%
DJF
65.6%
CALIPSO ISCCP
![Page 9: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/9.jpg)
9
Profile of Cloud Frequency
Black -> All Layers Detected, Red -> Highest layer only
Tropics 30N - 60N
![Page 10: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/10.jpg)
10
High Clouds - SON
ISCCP (2005)CALIOP (2006)
![Page 11: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/11.jpg)
11
High Opaque Clouds - SON
CALIPSO
ISCCP (IR clouds)
ISCCP
CALIOP
![Page 12: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/12.jpg)
12
High clouds, diurnal difference – Jan 2007
night day
![Page 13: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/13.jpg)
13
Cloud layer-average backscatter (V2.01)
Night Day
5-km avg
80-km avg
Histograms of layer-average cloud backscatter for 5-km and 80-km layers July 1-7, 2006.
3E-4/km/sr
3E-3/km/sr2E-3/km/sr
6E-4/km/sr
min ~ 0.0025
min ~ 0.025min ~ 0.017
min ~ 0.005
min estimated from distribution of layer IAB
![Page 14: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/14.jpg)
14
Middle Clouds - SON
CALIPSO
ISCCP (IR clouds)
ISCCP (2005)
CALIOP (2006)
![Page 15: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/15.jpg)
15
Low Clouds - JJA
ISCCP: 25.2%
CALIPSO: 49.4%
CALIPSO, single-layer low cloud: 27.5%
![Page 16: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/16.jpg)
16
Sensitivity to layers underneath thin clouds (night)
weaker layers disappear as overlying layer becomes optically thicker
Stratus detectable underneath clouds of optical depth ~ 5
Aerosols detectable underneath clouds of optical depth 1-2
![Page 17: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/17.jpg)
17
8 July, 1200Z
532 nm
1064 nm
![Page 18: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/18.jpg)
18
Cloud layer-average backscatter distributions (V2.01)
Night Day
Histograms of layer-average cloud backscatter for single-shot clouds,July 1-7, 2006.
2E-2/km/sr1E-2/km/sr
min~ 0.17min~ 0.1
![Page 19: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/19.jpg)
19
Antarctica
All cloud Opaque cloud
winter
(JJA)
summer
(DJF)
![Page 20: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/20.jpg)
20
15 June 2006
Antarctic winter
![Page 21: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/21.jpg)
21
Annual cycle of polar cloud, 60S – 82Sland only
all cloud
high cloud
![Page 22: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/22.jpg)
22
Profile of Cloud Frequency: Antarctica
Black -> All Layers, Red -> Highest layer only
Summer Winter
![Page 23: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/23.jpg)
23
CALIPSO Is Providing A Wealth of Information on Polar Stratospheric Clouds
Extensive measurement coverage over polar regions into polar night
![Page 24: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/24.jpg)
24
Annual cycle: global total cloud
CALIPSO ISCCP* TOVS-B* HIRS*
Global annual mean (%) 77.8 66 73 75
RMS difference (%) 0.26 2.3 2.4 3.5
* 1987-1995
![Page 25: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/25.jpg)
25
25
Zonal fraction of ice and water
Ice/water determination is based on depolarization signature
![Page 26: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/26.jpg)
26
Fraction of Ice and Water Cloud
Cloud Fraction = Cloud (all, ice, or water) / # of Samples Cloud Fraction = Cloud (ice or water) / Cloud (all)
Cloud, Ice Cloud, Water Cloud
Tropics
NH mid-latitudes
misclassifications likely
![Page 27: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/27.jpg)
27
CALIPSO-CERES collaboration
Surface and atmospheric fluxes estimated from:
Cloud profiles: CALIPSO, CloudSat
Cloud/aerosol properties: CALIPSO, CloudSat, MODIS
TOA radiances: CERES
![Page 28: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/28.jpg)
28
Flux Profiles: first example
![Page 29: 1 An initial CALIPSO cloud climatology ISCCP Anniversary, 23-25 July 2008, New York Dave Winker NASA LaRC.](https://reader036.fdocuments.us/reader036/viewer/2022062803/56649cef5503460f949bd403/html5/thumbnails/29.jpg)
29
Next Steps
Complete evaluation of cloud statistics for GEWEX assessement
Development and distribution of Level 3 cloud product
Improve cirrus optical depth, ice/water classification– Cloud fraction as a function of cloud optical depth
– Cloud fraction by cloud type
Characterize uncertainties due to sparse spatial sampling
Climatologies of other cloud properties (, etc)
Coordinate with CALIPSO simulator group at LMD