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  • Climate variability in the northern Levant from the highly resolved Qadisha record (Lebanon) during the Holocene optimum
Title: Climate variability in the northern Levant from the highly resolved Qadisha record (Lebanon) during the Holocene optimum
Abstract New stalagmites from Qadisha Cave (Lebanon) located at 1720 m above sea level provide a high-resolution and well-dated record for northern Mount Lebanon. The stalagmites grew discontinuously from 9.2 to 5.7 and at 3.5 ka, and they show a tendency to move from a more negative oxygen isotope signal at ~9.1 ka to a more positive signal at ~5.8 ka. Such a trend reflects a change from a wetter to a drier climate at high altitudes. The δ 13 C signal shows rapid shifts throughout the record and a decreasing trend toward more negative values in the mid-Holocene, suggesting enhanced soil activity. In the short-term trend, Qadisha stalagmites record rapid dry/wet changes on centennial scales, with a tendency to more rapid dry events toward the mid-Holocene. Such changes are characterized by overall good agreement between both geochemical proxies and stalagmite growth and might be affected by the seasonal variations in snow cover. The Qadisha record is in good agreement with other Levantine records, showing more humid conditions from 9 to 7 ka. After 7 ka, a drier climate seems to affect sites at both low- and high-altitude areas. The Qadisha record reflects uniquely mountainous climate characteristics compared with other records, specifically the effect of snow cover and its duration regulating the effective infiltration.  more » « less
Award ID(s):
2202913
PAR ID:
10451312
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Quaternary Research
ISSN:
0033-5894
Page Range / eLocation ID:
1 to 15
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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