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| Titel |
The global land shortwave cryosphere radiative effect during the MODIS era |
| VerfasserIn |
D. Singh, M. G. Flanner, J. Perket |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1994-0416
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| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 9, no. 6 ; Nr. 9, no. 6 (2015-11-10), S.2057-2070 |
| Datensatznummer |
250116866
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| Publikation (Nr.) |
 copernicus.org/tc-9-2057-2015.pdf |
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| Zusammenfassung |
| The shortwave cryosphere radiative effect (CrRE) is the instantaneous
influence of snow and ice cover on Earth's top-of-atmosphere (TOA) solar
energy budget. Here, we apply measurements from the MODerate resolution
Imaging Spectroradiometer (MODIS), combined with microwave retrievals of
snow presence and radiative kernels produced from four different models, to
derive CrRE over global land during 2001–2013. We estimate global annual-mean land CrRE during this period of −2.6 W m−2, with variations from −2.2 to −3.0 W m−2 resulting from use of different kernels and
variations of −2.4 to −2.6 W m−2 resulting from different algorithmic
determinations of snow presence and surface albedo. Slightly more than half
of the global land CrRE originates from perennial snow on Antarctica,
whereas the majority of the northern hemispheric effect originates from
seasonal snow. Consequently, the northern hemispheric land CrRE peaks at
−6.0 W m−2 in April, whereas the southern hemispheric effect more
closely follows the austral insolation cycle, peaking at −9.0 W m−2 in
December. Mountain glaciers resolved in 0.05° MODIS data contribute
about −0.037 W m−2 (1.4 %) of the global effect, with the majority
(94 %) of this contribution originating from the Himalayas. Interannual
trends in the global annual-mean land CrRE are not statistically significant
during the MODIS era, but trends are positive (less negative) over large
areas of northern Asia, especially during spring, and slightly negative over
Antarctica, possibly due to increased snowfall. During a common overlap
period of 2001–2008, our MODIS estimates of the northern hemispheric land
CrRE are about 18 % smaller (less negative) than previous estimates
derived from coarse-resolution AVHRR data, though interannual variations
are well correlated (r = 0.78), indicating that these data are useful in
determining longer-term trends in land CrRE. |
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