High-frequency shifts in the Indian summer monsoon following termination of the YD event. (1st May 2021)

• Record Type: Journal Article
• Authors: Gupta, Anil K.; Singh, Raj K.; Dutt, Som; Cheng, Hai; Clemens, Steven C.; Kathayat, Gayatri
• Is Part Of: Quaternary science reviews. Volume 259(2021)
• Publication Date: 2021-05-01
• Subjects: Indian summer monsoon -- Younger Dryas -- Bølling-Ållerød period -- Abrupt wet and dry intervals -- Umsynrang cave -- Meghalaya; Geology, Stratigraphic -- Quaternary -- Periodicals; Stratigraphie -- Quaternaire -- Périodiques; 551.79
• DOI: 10.1016/j.quascirev.2021.106888
• Languages: English
• ISSNs: 0277-3791

Abstract

Abstract: High-resolution multi-proxy records are pivotal to analyze Indian monsoon variability and its linkages with socio-economic growth in South Asia. To constrain short-term shifts in the Indian monsoon, we analyzed a speleothem sample from Meghalaya, northeastern India encompassing ∼15.4 to 10.1 kilo year before the Present (kyr BP). Our new speleothem data from Meghalaya suggests wet conditions in northeastern India during ∼15.4 to 12.9 kyr BP and ∼11.3 to 10.1 kyr BP, punctuated by a dry phase during ∼12.9 to 11.3 kyr BP including the Younger Dryas (YD) cold interval. We suggest a southward shift of the Intertropical Convergence Zone (ITCZ) in addition to weak Atlantic Meridional Overturning Circulation and land-sea heat contrast during the YD event leading to a weak Indian summer monsoon. The Northern Hemisphere atmospheric heating shift the ITCZ northward, but our data shows high-frequency shifts in the ISM during ∼11.3 to 10.1 kyr BP following termination of the YD cold event. This interval also shows a higher growth rate of the studied speleothem sample. Highlights: Strong Indian summer monsoon during the Bølling-Ållerød and early Holocene. A weak Indian Summer Monsoon during the Younger Dryas cold event. High-frequency changes in precipitation following termination of the Younger Dryas.