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| Titel |
Comparison of Global Cloud Climatologies |
| VerfasserIn |
Alexander V. Chernokulsky, Igor I. Mokhov |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250032845
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| Zusammenfassung |
| An analysis was carried out to intercompare several up-to-date cloudiness datasets
including satellite data (ISCCP D2, UW HIRS, Patmos-X, MODIS, PARASOL,
SCIAMACHY) and surface observations (EECRA, CRU, ICOADS) as well as
reanalyses data (NCEP/NCAR, NCEP/DOE, ERA-40, ERA-Interim, JRA-25) and global
climate models simulations (CMIP3) in terms of global, zonal and regional values of
cloudiness.
The amount of global annual mean cloudiness (GAC) from different observations is about
2/3 in average. It reaches 3/4 for certain data. The amount of GAC is estimated between 1/2
and 3/5 over land and about 7/10 over ocean. According to all observations clouds amount in
the Southern Hemisphere is larger than in the Northern Hemisphere with maximum in
summer and minimum in winter.
The amount of GAC according to reanalyses is evaluated between 1/2 and 3/5. According
to model simulations the amount of GAC is estimated in a wide range from 1/2 up to 3/4 with
3/5 as ensemble mean. On the whole, reanalyses and model simulations produce less amount
of GAC than observations.
The largest distinctions between different satellite data are noted over regions with high
albedo, in particular over polar regions and subtropical deserts. Major distinctions
between different reanalyses data are noted over the eastern boundary ocean currents. |
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