Speleothem‐Based Hydroclimate Reconstructions During the Penultimate Deglaciation in Northern China

Abstract

Hydroclimatic change has a substantial impact on the lives and well-being of humans, especially in densely populated regions (Yang et al., 2015). As recorded in historical literature and as is known through modern observations, floods and droughts have occurred frequently in China, affecting not only agricultural production and regional economies, but also water security in China. Understanding the past variability of hydroclimatic change and its dynamics is essential for projecting future changes and mitigating the potential influence of climate change. Instrumental records usually not exceed 70 years, or 150 years in some cities in China. These records are too short to provide a full understanding of the variability of hydroclimatic change and the underlying forcing mechanisms. Therefore, the reconstruction of past hydroclimatic conditions by using various archives has generally been the focus of past climate change studies.As a type of secondary carbonate deposition that grew within caves, speleothem has been regarded as one of the most important archives in paleoclimate-related and paleoenvironmental studies. Chinese speleothem δ 18 O records have demonstrated Asian monsoon variability over the last seven glacial-interglacial transitions (Cheng et al., 2016; references therein). In terms of the penultimate deglaciation, Asian monsoon variability, driving forces, and the timing and structure of Termination II have been discussed based on various speleothem δ 18 O records (

Hydroclimatic changes in south-central China during the 4.2 ka event and their potential impacts on the development of Neolithic culture

“…Factors influencing X/Ca ratios in speleothems are diverse, including hydrological processes (e.g., WRI, PAP/PCP), temperature, and speleothem growth rate, among others (Treble et al, 2003; Fairchild and Treble, 2009; Tan et al, 2014; Xue et al, 2021). In previous studies, trace elements varying positively in tandem with δ 13 C were suggested to be caused by rainfall-related hydrological processes (Cheng et al, 2016b; Tan et al, 2020b; Xue et al, 2021). Specifically, under dry climate conditions, prolonged WRI could increase the dissolution of bedrock.…”

“…Although several speleothem records are available from central and southern China, for example, from the Sanbao (Dong et al, 2010; Cheng et al, 2016a), Lianhua (LH) (Cosford et al, 2008; H. Zhang et al, 2013), and Dongge (DG) Caves (Yuan et al, 2004; Wang et al, 2005), the climatic significance of these stalagmite δ 18 O records is highly debated and subject to multiple interpretations (e.g., moisture sources and pathways, upstream rainout, and regional rainfall) (Yuan et al, 2004; Maher and Thompson, 2012; Tan et al, 2018a). The δ 13 C and trace elements ratios (e.g., Sr/Ca, Mg/Ca, and Ba/Ca) in stalagmites, which reflect the local hydrological environment (Fairchild and Treble, 2009; Xue et al, 2021; Zhang et al, 2021), are thus better suited to reconstruct the local rainfall variability. In this study, we present a suite of stalagmite-based stable isotope (δ 18 O, δ 13 C) and trace element records (Sr/Ca, Mg/Ca, Ba/Ca) from Remi Cave, Hunan Province, aiming to reconstruct the monsoon precipitation variations in south-central China across the 4.2 ka event.…”

Orbital‐ to millennial‐scale variation of the speleothem δ18O record during Marine Isotope Stages 5 to 3 on the southeast Chinese Loess Plateau and its climatic and environmental implications

“…The interpretation of speleothem δ 13 C Speleothem δ 13 C has often been linked to various factors, including the type of vegetation (i.e. C 3 vs C 4 ) above the cave, which determine the δ 13 C of soil CO 2 , biomass, which affects the soil CO 2 concentration, biological activities in the soil, carbon component dissolved from the host rock and prior carbonate precipitation (PCP) in the epikarst and within the cave (McDermott, 2004;Genty et al, 2006;Ridley et al, 2015;Lechleitner et al, 2017;Fohlmeister et al, 2020;Xue et al, 2021). In northern China, precipitation is the dominant factor affecting vegetation density and/or types and then plays an important role in causing changes in the speleothem δ 13 C record (Li et al, 2020).…”