Abstract
Abstract. Ice cores from the Tibetan Plateau (TP) are widely used for reconstructing past climatic and environmental conditions that extend beyond the instrumental period. However, challenges in dating and interpreting ice core records often lead to inconsistent results. The Guliya ice core drilled from the northwestern TP suggested a cooling trend during the mid-Holocene based on its decreasing δ18O values, which is not observed in other Tibetan ice cores. Here we present a new high-resolution δ18O record of the Chongce ice cores drilled to bedrock ∼30 km away from the Guliya ice cap. Our record shows a warming trend during the mid-Holocene. Based on our results as well as previously published ice core data, we suggest that the apparent discrepancy between the Holocene δ18O records of the Guliya and the Chongce ice cores may be attributed to a possible misinterpretation of the Guliya ice core chronology.
Highlights
Global climate models simulate a warming trend during the Holocene epoch, typically attributed to retreating ice sheets and rising atmospheric greenhouse gases, while global cooling was inferred from proxy reconstructions obtained mainly from the analysis of marine sediment cores (Marcott et al, 2013)
The Guliya ice core drilled from the northwestern Tibetan Plateau (TP) suggested a cooling trend during the mid-Holocene based on its decreasing δ18O values, which is not observed in other Tibetan ice cores
We provided a new high-resolution δ18O record of the Chongce ice cores drilled from the northwestern TP
Summary
Global climate models simulate a warming trend during the Holocene epoch, typically attributed to retreating ice sheets and rising atmospheric greenhouse gases, while global cooling was inferred from proxy reconstructions obtained mainly from the analysis of marine sediment cores (Marcott et al, 2013). Marsicek et al (2018) recently presented temperature reconstructions derived from sub-fossil pollen across North America and Europe These records show a general long-term warming trend for the Holocene until ∼ 2 ka BP (thousand years before present; present measured from 1950 AD), and records with cooling trends are largely limited to the North Atlantic, implying varied regional climate responses to global drivers. Among all the published Tibetan ice cores, the Guliya ice core drilled to bedrock (308.6 m) from the northwestern TP (Fig. S1 in the Supplement) is unique due to the exceptional length of its temporal coverage, estimated to be > 500 ka below the depth of 290 m (i.e., 18.6 m above the ice–bedrock interface) or up to ∼ 760 ka at the ice– bedrock interface based on 36Cl dead ice in the bottom section (Thompson et al, 1997). Its stable isotopic record suggests a cooling mid-Holocene based on its decreasing δ18O values
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
