TY  - JOUR
A1  - Wang, Yongbo
A1  - Bekeschus, Benjamin
A1  - Handorf, Doerthe
A1  - Liu, Xingqi
A1  - Dallmeyer, Anne
A1  - Herzschuh, Ulrike
T1  - Coherent tropical-subtropical Holocene see-saw moisture patterns in the Eastern Hemisphere monsoon systems
JF  - Quaternary science reviews : the international multidisciplinary research and review journal
N2  - The concept of a Global Monsoon (GM) has been proposed based on modern precipitation observations, but its application over a wide range of temporal scales is still under debate. Here, we present a synthesis of 268 continental paleo-moisture records collected from monsoonal systems in the Eastern Hemisphere, including the East Asian Monsoon (EAsM), the Indian Monsoon (IM), the East African Monsoon (EAfM), and the Australian Monsoon (AuM) covering the last 18,000 years. The overall pattern of late Glacial to Holocene moisture change is consistent with those inferred from ice cores and marine records. With respect to the last 10,000 years (10 ka), i.e. a period that has high spatial coverage, a Fuzzy c-Means clustering analysis of the moisture index records together with "Xie-Beni" index reveals four clusters of our data set. The paleoclimatic meaning of each cluster is interpreted considering the temporal evolution and spatial distribution patterns. The major trend in the tropical AuM, EAfM, and IM regions is a gradual decrease in moisture conditions since the early Holocene. Moisture changes in the EAsM regions show maximum index values between 8 and 6 ka. However, records located in nearby subtropical areas, i.e. in regions not influenced by the intertropical convergence zone, show an opposite trend compared to the tropical monsoon regions (AuM, EAfM and IM), i.e. a gradual increase. Analyses of modern meteorological data reveal the same spatial patterns as in the paleoclimate records such that, in times of overall monsoon strengthening, lower precipitation rates are observed in the nearby subtropical areas. We explain this pattern as the effect of a strong monsoon circulation suppressing air uplift in nearby subtropical areas, and hence hindering precipitation. By analogy to the modern system, this would mean that during the early Holocene strong monsoon period, the intensified ascending airflows within the monsoon domains led to relatively weaker ascending or even descending airflows in the adjacent subtropical regions, resulting in a precipitation deficit compared to the late Holocene. Our conceptual model therefore integrates regionally contrasting moisture changes into the Global Monsoon hypothesis. (C) 2017 Elsevier Ltd. All rights reserved.
KW  - Global monsoon
KW  - Holocene
KW  - Eastern hemisphere
KW  - Moisture evolution
Y1  - 2017
U6  - https://doi.org/10.1016/j.quascirev.2017.06.006
SN  - 0277-3791
VL  - 169
SP  - 231
EP  - 242
PB  - Elsevier
CY  - Oxford
ER  -