Paleoclimate reconstruction in the Levant region from the geochemistry of a Holocene stalagmite from the Jeita cave, Lebanon

Abstract

Dated oxygen and carbon isotopic profiles from a Holocene stalagmite (11.9–1.1 ka) from the Jeita cave, Lebanon, are compared to variations in crystallographic habit, stalagmite diameter and growth rate. The profiles show generally high δ18O and δ13C values during the late-glacial period, low values during the early Holocene, and again high values after 5.8 ka. On the basis of the good correlation between the morphological and crystallographic aspect of the stalagmite and its isotopic records, as well as the isotopic response of speleothems from central and northern Israel, we relate high δ18O and δ13C values to drier conditions. Between 6.5 and 5.8 ka an increase in isotopic values, a decrease in growth rate and stalagmite diameter suggest a transition from wet conditions in the early Holocene towards drier conditions in the mid-Holocene. The transition occurred in two steps, first a progressive change to drier conditions started at 6.5 ka but was interrupted by a short (∼ 100 years) return to wetter conditions, followed by an equally rapid (< 200 years) change to drier conditions.

The global monsoon across timescales: coherent variability of regional monsoons

“…Speleothem δ 18 O records from Israel and Lebanon have also been demonstrated to be a useful proxy for the North African monsoon change whose variability, to first order, tracks surface seawater δ 18 O changes in the eastern Mediterranean Sea (Bar- Matthews et al, 2003), as the latter is influenced strongly by river discharge from the North African monsoon region. These speleothem records show variability during the Holocene pattern similar to other proxies for the North African monsoon region (Bar-Matthews et al, 2003;Verheyden et al, 2008). Recently, a correlation has been revealed between an eastern Mediterranean record (color reflectance from the ODP 968 core) and Asian monsoon records (Ziegler et al, 2010b), which suggests coordinated changes in the Asian and North African monsoons (Fig.…”

“…Although it is outside of the modern Asian monsoon domain, it may be influenced by the summer monsoon incursions during the mid-Holocene (Cheng et al, 2012b;Kutzbach et al, 2014). (d) Eastern Mediterranean records from Soreq Cave (brown, Bar-Matthews et al, 2003) and Jeita Cave, Lebanon (blue, Verheyden et al, 2008). (e) The seawater δ 18 O record from the marine sediment core (MD03-270) (Weldeab et al, 2007).…”

Hydrological variability in the Northern Levant: a 250 ka multi-proxy record from the Yammoûneh (Lebanon) sedimentary sequence

“…This early Holocene wetting was shown at other sites from Lebanon (see site location in Fig. 1) by changes in growth rate, δ 18 O and δ 13 C in a 12 ka speleothem from Jeita Cave (Verheyden et al, 2008), and by the ∼15 ka-pollen records from the Aammish marsh in the Bakka Plain (Hajar et al, 2008(Hajar et al, , 2010. Pollen data from the Ghab Valley, Syria (Yasuda et al, 2000) show similar trends.…”

Monitoring of a fast-growing speleothem site from the Han-sur-Lesse cave, Belgium, indicates equilibrium deposition of the seasonal δ<sup>18</sup>O and δ<sup>13</sup>C signals in the calcite

“…In the past 25 years, speleothem records have provided important information on past climate variations on multimillennial to decadal scales (e.g., Genty et al, 2003;McDermott, 2005;Verheyden et al, 2008b;Wang et al, 2008;Van Rampelbergh et al, 2013). With the increasing number of studies on cave calcite deposition dynamics (e.g., Dreybrodt, 1999Dreybrodt, , 2008Verheyden et al, 2008a;Lachniet, 2009;Scholz et al, 2009;Ruan and Hu, 2010;Oster et al, 2012) and with the help of modern analytical tools (Fairchild et al, 2006;Spötl and Mattey, 2006;Jochum et al, 2012), progress has been made to measure resolution at sub-seasonal and even bi-monthly scales.…”