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| Titel |
A closer looking at dimming and brightening in China during 1961-2005 |
| VerfasserIn |
X. Xia |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
0992-7689
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| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 28, no. 5 ; Nr. 28, no. 5 (2010-05-17), S.1121-1132 |
| Datensatznummer |
250016831
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| Publikation (Nr.) |
 copernicus.org/angeo-28-1121-2010.pdf |
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| Zusammenfassung |
| This study investigates dimming and brightening of surface solar
radiation (SSR) during 1961–2005 in China as well as its relationships to
total cloud cover (TCC). This is inferred from daily ground-based
observational records at 45 pyranometer stations. A statistical method is
introduced to study contributions of changes in the frequency of TCC
categories and their atmospheric transparency to the secular SSR trend. The
surface records suggest a renewed dimming beyond 2000 in North China after
the stabilization in the 1990s; however, a slight brightening appears beyond
2000 in South China. Inter-annual variability of SSR is negatively
correlated with that of TCC, but there is a positive correlation between
decadal variability of SSR and TCC in most cases. The dimming during
1961–1990 is exclusively attributable to decreased atmospheric transparency,
a portion of which is offset by TCC frequency changes in Northeast and
Southwest China. The dimming during 1961–1990 in Northwest and Southeast
China primarily results from decreased atmospheric transparency under all
sky conditions and the percentage of dimming stemming from TCC frequency
changes is 11% in Northwest and 2% in Southeast China. Decreased
atmospheric transparencies during 1991–2005 in North China in most cases
lead to the dimming. TCC frequency changes also contribute to the dimming
during this period in North China. This feature is more pronounced in summer
and winter when TCC frequency changes can account for more than 80% of
dimming. In South China, increased atmospheric transparencies lead to the
brightening during 1991–2005. A substantial contribution by TCC frequency
changes to the brightening is also evident in spring and autumn. |
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