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| Titel |
Variation in the Asian monsoon intensity and dry–wet conditions since the Little Ice Age in central China revealed by an aragonite stalagmite |
| VerfasserIn |
J.-J. Yin, D.-X. Yuan, H.-C. Li, H. Cheng, T.-Y. Li, R. L. Edwards, Y.-S. Lin, J.-M. Qin, W. Tang, Z.-Y. Zhao, H.-S. Mii |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1814-9324
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| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 10, no. 5 ; Nr. 10, no. 5 (2014-10-01), S.1803-1816 |
| Datensatznummer |
250117056
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| Publikation (Nr.) |
 copernicus.org/cp-10-1803-2014.pdf |
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| Zusammenfassung |
This paper focuses on the climate variability in central China since AD 1300,
involving:
(1) a well-dated, 1.5-year resolution stalagmite δ18O record
from Lianhua Cave, central China
(2) links of the δ18O record with regional dry–wet conditions,
monsoon intensity, and temperature over eastern China
(3) correlations among drought events in the Lianhua record, solar
irradiation, and ENSO (El Niño–Southern Oscillation) variation.
We present a highly precise, 230Th / U-dated, 1.5-year resolution
δ18O record of an aragonite stalagmite (LHD1) collected from
Lianhua Cave in the Wuling Mountain area of central China. The comparison of
the δ18O record with the local instrumental record and historical
documents indicates that (1) the stalagmite δ18O record reveals
variations in the summer monsoon intensity and dry–wet conditions in the
Wuling Mountain area. (2) A stronger East Asian summer monsoon (EASM)
enhances the tropical monsoon trough controlled by ITCZ (Intertropical
Convergence Zone), which produces higher spring quarter rainfall and
isotopically light monsoonal moisture in the central China. (3) The summer
quarter/spring quarter rainfall ratio in central China can be a potential
indicator of the EASM strength: a lower ratio corresponds to stronger EASM
and higher spring rainfall. The ratio changed from <1 to
>1 after 1950, reflecting that the summer quarter rainfall of
the study area became dominant under stronger influence of the Northwestern
Pacific High. Eastern China temperatures varied with the solar activity,
showing higher temperatures under stronger solar irradiation, which produced
stronger summer monsoons. During Maunder, Dalton and 1900 sunspot minima,
more severe drought events occurred, indicating a weakening of the summer
monsoon when solar activity decreased on decadal timescales. On an
interannual timescale, dry conditions in the study area prevailed under El
Niño conditions, which is also supported by the spectrum analysis. Hence,
our record illustrates the linkage of Asian summer monsoon precipitation to
solar irradiation and ENSO: wetter conditions in the study area under
stronger summer monsoon during warm periods, and vice versa. During cold
periods, the Walker Circulation will shift toward the central Pacific under
El Niño conditions, resulting in a further weakening of Asian summer
monsoons. |
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