Heterogenous Late Holocene Climate in the Eastern Mediterranean—The Kocain Cave Record From SW Turkey

Matthew J. Jacobson,Pascal Flohr,Aleksey Sadekov,Alison Gascoigne,R. Lawrence Edwards,Okan Tüysüz,Dominik Fleitmann,Melanie J. Leng,Hai Cheng

doi:10.1029/2021gl094733

Abstract

AbstractPalaeoclimate variability must be constrained to predict the nature and impacts of future climate change in the Eastern Mediterranean. Here, we present a late Holocene high‐resolution multiproxy data set from Kocain Cave, the first of its kind from SW Turkey. Regional fluctuations in effective‐moisture are recorded by variations in magnesium, strontium, phosphorous and carbon isotopes, with oxygen isotopes reacting to changes in precipitation and effective‐moisture. The new record shows a double‐peak of arid conditions at 1150 and 800 BCE, a wet period 330–460 CE followed by a rapid shift to dry conditions 460–830 CE, and a dry/wet Medieval Climate Anomaly/Little Ice Age pattern. Large discrepancies exist between Turkish records and the Kocain record, which shares more similarities with other Eastern Mediterranean coastal records. Heterogeneity of regional climate and palaeoclimate proxy records are emphasized.

Highlights

To predict the nature and impacts of future climate change in the Eastern Mediterranean (EM), a “hotspot” which will experience severe impacts (Giorgi, 2006), past climatic variability must be constrained (Masson-Delmotte et al, 2013)
We present a late Holocene high-resolution multiproxy data set from Kocain Cave, the first of its kind from SW Turkey
Regional fluctuations in effective-moisture are recorded by variations in magnesium, strontium, phosphorous and carbon isotopes, with oxygen isotopes reacting to changes in precipitation and effective-moisture

Summary

Introduction

To predict the nature and impacts of future climate change in the Eastern Mediterranean (EM), a “hotspot” which will experience severe impacts (Giorgi, 2006), past climatic variability must be constrained (Masson-Delmotte et al, 2013). Agricultural droughts in (semi-)arid regions have a greater societal impact than individual climatic variables (Dalezios et al, 2017; Jones et al, 2019; Mannocchi et al, 2004) Reconstructing this variability requires a dense network of precisely dated and highly resolved palaeoclimate records. Stable-isotopes from Lake Gölhisar (Eastwood et al, 2007) reveal low-resolution (∼80 years) changes in lake water balance (LWB) throughout the Holocene, albeit with significant dating uncertainties of ±165 years This record and tree-rings are seasonally biased towards spring/summer, whereas precipitation mainly occurs in winter (Peterson & Vose, 1997). An age-model is constructed from uranium-series dates (230Th), with supporting evidence from the impact of historically attested earthquakes on Ko-1 This enables us to establish high-resolution climate variability in SW Turkey for >3,000 years during the late Holocene

Cave Setting

Ko-1 Record and EM Palaeoclimate

Heterogeneity of Eastern Mediterranean Climate and Proxies

Conclusion

Findings

Data Availability Statement