Late Pliocene temperatures and their spatial variation at the southeastern border of the Qinghai-Tibet Plateau

Autor(en)

Yong-Jiang Huang, Wen-Yun Chen, Frédéric M.B. Jacques, Yu-Sheng Christopher Liu, Torsten Utescher, Tao Su, David-Kay Ferguson, Zhe-Kun Zhou

Abstrakt

It is widely accepted that the late Pliocene spans a time with globally warmer conditions compared to today. Regional specifics in temperature patterns from this period, however, remain poorly known. In this study, we reconstruct quantitatively late Pliocene climates for eight sites at the southeastern border of the Qinghai-Tibet Plateau (SBTP), based on palaeobotanical data compiled from published sources using the Coexistence Approach (CoA), and analyze anomalies with respect to modern climates. The reconstructed temperatures indicate that in the late Pliocene, the northwestern part of the study area was cooler than its southern part. This spatial differentiation in temperature was largely due to differences in altitude: the northwest of the SBTP probably had higher altitudes than the south at that time. Mean annual temperatures (MATs) were around 1. °C higher than today, suggesting a cooling trend since the late Pliocene. Our data show that summer temperatures have declined significantly since the late Pliocene while winter temperatures have remained similar to those of the present, different from observations in other territories. The unexpected summer and winter temperature changes can be explained by the regional orogenic uplift plus the global cooling. The eastward extrusion of the Qinghai-Tibet Plateau might have blocked the southward cold high pressure of the winter monsoon and forced it to circumvent the eastern flank of the plateau, weakening its impact on the SBTP. The post-Pliocene mountain uplift increased the overall altitude of the region, which caused the temperature decline for both summer and winter. The reconstructed summer precipitation was lower while the winter precipitation was higher than today, suggesting a weaker monsoon climate during the late Pliocene.

Organisation(en)

Institut für Paläontologie

Externe Organisation(en)

Chinese Academy of Sciences (CAS), East Tennessee State University, Rheinische Friedrich-Wilhelms-Universität Bonn

Journal

Journal of Asian Earth Sciences

Band

111

Seiten

44-53

Anzahl der Seiten

10

ISSN

1367-9120

DOI

https://doi.org/10.1016/j.jseaes.2015.04.048

Publikationsdatum

2015

Peer-reviewed

Ja

ÖFOS 2012

105117 Paläobotanik

Schlagwörter

ASJC Scopus Sachgebiete

Earth-Surface Processes, Geology

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/late-pliocene-temperatures-and-their-spatial-variation-at-the-southeastern-border-of-the-qinghaitibet-plateau(d45a88f1-ab3c-4144-8483-a172cf084208).html