scholarly journals Variability of the Asian summer monsoon during the penultimate glacial/interglacial period inferred from stalagmite oxygen isotope records from Yangkou cave, Chongqing, Southwestern China

2013 ◽  
Vol 9 (6) ◽  
pp. 6287-6309
Author(s):  
T.-Y. Li ◽  
C.-C. Shen ◽  
L.-J. Huang ◽  
X.-Y. Jiang ◽  
X.-L. Yang ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Mainland China ◽  
Walker Circulation ◽  
Interglacial Period ◽  
Trade Winds ◽  
Comprehensive Picture ◽  
Isotope Record ◽  
Asian Summer

Abstract. The orbital-timescale dynamics of the Quaternary Asian summer monsoons (ASM) are frequently attributed to precession-dominated Northern Hemisphere summer insolation. However, this ASM variability is inferred primarily from oxygen isotope records of stalagmites, mainly from Sanbao cave in mainland China, and may not provide a comprehensive picture of ASM evolution. A new spliced stalagmite oxygen isotope record from Yangkou cave tracks summer monsoon precipitation variation from 124–206 thousand years ago in Chongqing, southwest China. When superimposed on the Sanbao record, the Yangkou-inferred precipitation time series is shown to support the strong ASM periods at marine isotope stages (MIS) 6.3, 6.5, and 7.1 and weak ASM intervals at MIS 6.2, 6.4, and 7.0. This consistency confirms that ASM events affected most of mainland China. We show that change in glacial/interglacial (G/IG) ASM intensity was also governed by the Walker Circulation by combining our results with published paleo-Pacific thermal and salinity records. One of the strongest ASM events over the past fiver G/IG cycles, at MIS 6.5, was enhanced by such zonal forcing associated with prevailing trade winds in the Pacific.

scholarly journals Stalagmite-inferred variability of the Asian summer monsoon during the penultimate glacial–interglacial period

2014 ◽  
Vol 10 (3) ◽  
pp. 1211-1219 ◽  
Author(s):  
T.-Y. Li ◽  
C.-C. Shen ◽  
L.-J. Huang ◽  
X.-Y. Jiang ◽  
X.-L. Yang ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Mainland China ◽  
Warm Pool ◽  
Trade Wind ◽  
Interglacial Period ◽  
Solar Insolation ◽  
The North ◽  
Asian Summer

Abstract. The orbital-timescale dynamics of the Quaternary Asian summer monsoons (ASM) are frequently attributed to precession-dominated northern hemispheric summer insolation. However, this long-term continuous ASM variability is inferred primarily from oxygen isotope records of stalagmites, mainly from Sanbao cave in mainland China, and may not provide a comprehensive picture of ASM evolution. A new spliced stalagmite oxygen isotope record from Yangkou cave tracks summer monsoon precipitation variation from 124 to 206 thousand years ago in Chongqing, southwest China. Our Yangkou record supports that the evolution of ASM was dominated by the North Hemisphere solar insolation on orbital timescales. When superimposed on the Sanbao record, the precipitation time series referred from Yangkou cave stalagmites supports the strong ASM periods at marine isotope stages (MIS) 6.3, 6.5, and 7.1 and weak ASM intervals at MIS 6.2, 6.4, and 7.0. This consistency confirms that ASM events affected most of mainland China. Except for the solar insolation forcing, the large amplitude of minimum δ18O values in Yangkou record during glacial period, such as MIS 6.5, could stem from the enhanced prevailing Pacific trade wind and/or continental shelf exposure in the Indo–Pacific warm pool.

scholarly journals A 338-year tree-ring oxygen isotope record from Thai teak captures the variations in the Asian summer monsoon system

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Nathsuda Pumijumnong ◽  
Achim Bräuning ◽  
Masaki Sano ◽  
Takeshi Nakatsuka ◽  
Chotika Muangsong ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Tree Ring ◽  
Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Oxygen Isotope Record ◽  
Isotope Record ◽  
Monsoon System ◽  
Asian Summer

Seasonal variations in the lake-water oxygen isotope composition of four lakes in the East Asian summer monsoon region: Implications for the interpretation of paleo-isotope records

2019 ◽  
Vol 44 (4) ◽  
pp. 572-588 ◽  
Author(s):  
Zhiping Zhang ◽  
Jianbao Liu ◽  
Xiaokang Liu ◽  
Shengqian Chen ◽  
Ailing Yu ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Summer Monsoon ◽  
Lake Water ◽  
Seasonal Variations ◽  
East Asian Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Monsoon Season ◽  
East Asian ◽  
Water Oxygen ◽  
Asian Summer

The scarcity of modern process studies of the relationship between climatic variables and lake-water oxygen isotope (δ18OLW) composition has restricted our understanding of the climatic significance of oxygen isotope (δ18O) records from lake sediments. We measured changes in δ18OLW at four lakes (Nanyihu, Gonghai, Mayinghai and Xihaizi) at various locations across the East Asian summer monsoon (EASM) region, from December 2016 to January 2018. The variations in δ18OLW at Lake Nanyihu, located in the lower reach of the Yangtze River, are controlled by precipitation oxygen isotope (δ18OP) composition, temperature and evaporation during the non-monsoon season. However, the variations in δ18OLW at the lakes close to the northern limit of the EASM (Gonghai, Mayinghai and Xihaizi) are affected not only by δ18OP, temperature and evaporation, but also by the replenishment of groundwater during the non-monsoon season. In general, during the non-monsoon season, the variation of δ18OLW exhibits a variety of patterns and the controlling factors across the EASM region are complex. During the monsoon season, although the effect of evaporation-induced isotopic enrichment still affects δ18OLW, the variations in δ18OLW are more influenced by the supply of abundant precipitation with lower δ18OP to the lakes, which caused a substantial decrease in δ18OLW across the EASM region in this season. Therefore, the variations in δ18OLW mainly reflect the δ18OP of the EASM during the monsoon season. However, the timing of the peak in monsoon precipitation does not correspond well to minima in δ18OLW, and correlation analysis reveals that there is only a weak relationship between δ18OLW and precipitation/humidity at all four lakes during the monsoon season. These findings demonstrate that although δ18OLW can represent the δ18OP of the EASM, it does not reflect precipitation/humidity during the monsoon season. Overall, our findings indicate that the seasonal variations of δ18OLW across the EASM region are controlled by different climatic variables, which implies that the interpretation of lacustrine δ18O records across the EASM region as an indicator of regional effective precipitation/humidity needs to be reassessed.

Decoupling of the East Asian summer monsoon and Indian summer monsoon between 20 and 17 ka

2014 ◽  
Vol 82 (1) ◽  
pp. 146-153 ◽  
Author(s):  
Xiuyang Jiang ◽  
Yaoqi He ◽  
Chuan-Chou Shen ◽  
Shi-Yu Lee ◽  
Bang Yang ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Summer Monsoon ◽  
Indian Summer Monsoon ◽  
East Asian Summer Monsoon ◽  
Asian Summer Monsoon ◽  
East Asian ◽  
Central China ◽  
Last Deglaciation ◽  
Oxygen Isotope Stage ◽  
Asian Summer

AbstractMarine Oxygen Isotope Stage (MIS) 2, with its profound environmental and climatic changes from before the last glacial maximum (LGM) to the last deglaciation, is an ideal period for understanding the evolution of the East Asian summer monsoon (EASM) and Indian summer monsoon (ISM), two Asian monsoon sub-systems. With 875 stable oxygen isotope ratios and 43 230Th dates from stalagmites in Sanxing Cave, southwestern China, we construct and interpret a new, replicated, Asian summer monsoon (ASM) record covering 30.9–9.7 ka with decadal resolution. δ18O records from this site and other reported Chinese caves display similar long-term orbitally dominated trends and synchronous millennial-scale strong and weak monsoonal events associated with climate changes in high northern latitudes. Interestingly, Sanxing δ18O and Arabian Sea records show a weakening ISM from 22 to 17 ka, while the Hulu and Qingtian records from East and Central China express a 3-ka intensifying EASM from 20 to 17 ka. This decoupling between EASM and ISM may be due to different sensitivities of the two ASM sub-systems in response to internal feedback mechanisms associated with the complex geographical or land-ocean configurations.

Sign in / Sign up

Export Citation Format

Share Document