TY - JOUR
T1 - Evaluating the timing and structure of the 4.2 ka event in the Indian summer monsoon domain from an annually resolved speleothem record from Northeast India
AU - Kathayat, Gayatri
AU - Cheng, Hai
AU - Sinha, Ashish
AU - Berkelhammer, Max
AU - Zhang, Haiwei
AU - Duan, Pengzhen
AU - Li, Hanying
AU - Li, Xianglei
AU - Ning, Youfeng
AU - Lawrence Edwards, R.
N1 - Publisher Copyright:
© 2018 Author(s).
PY - 2018/11/30
Y1 - 2018/11/30
N2 - A large array of proxy records suggests that the "4.2 ka event" marks an approximately 300-year long period (∼ 3:9 to 4.2 ka) of major climate change across the globe. However, the climatic manifestation of this event, including its onset, duration, and termination, remains less clear in the Indian summer monsoon (ISM) domain. Here, we present new oxygen isotope (δ18O) data from a pair of speleothems (ML.1 and ML.2) from Mawmluh Cave, Meghalaya, India, that provide a high-resolution record of ISM variability during a period (∼ 3:78 and 4.44 ka) that fully encompasses the 4.2 ka event. The sub-annually to annually resolved ML.1 δ18O record is constrained by 18 230Th dates with an average dating error of ±13 years (2σ) and a resolution of∼ 40 years, which allows us to characterize the ISM variability with unprecedented detail. The inferred pattern of ISM variability during the period contemporaneous with the 4.2 ka event shares broad similarities and key differences with the previous reconstructions of ISM from the Mawmluh Cave and other proxy records from the region. Our data suggest that the ISM intensity, in the context of the length of our record, abruptly decreased at ∼ 4:0 ka (∼ ±13 years), marking the onset of a multi-centennial period of relatively reduced ISM, which was punctuated by at least two multi-decadal droughts between ∼ 3:9 and 4.0 ka. The latter stands out in contrast with some previous proxy reconstructions of the ISM, in which the 4.2 ka event has been depicted as a singular multicentennial drought.
AB - A large array of proxy records suggests that the "4.2 ka event" marks an approximately 300-year long period (∼ 3:9 to 4.2 ka) of major climate change across the globe. However, the climatic manifestation of this event, including its onset, duration, and termination, remains less clear in the Indian summer monsoon (ISM) domain. Here, we present new oxygen isotope (δ18O) data from a pair of speleothems (ML.1 and ML.2) from Mawmluh Cave, Meghalaya, India, that provide a high-resolution record of ISM variability during a period (∼ 3:78 and 4.44 ka) that fully encompasses the 4.2 ka event. The sub-annually to annually resolved ML.1 δ18O record is constrained by 18 230Th dates with an average dating error of ±13 years (2σ) and a resolution of∼ 40 years, which allows us to characterize the ISM variability with unprecedented detail. The inferred pattern of ISM variability during the period contemporaneous with the 4.2 ka event shares broad similarities and key differences with the previous reconstructions of ISM from the Mawmluh Cave and other proxy records from the region. Our data suggest that the ISM intensity, in the context of the length of our record, abruptly decreased at ∼ 4:0 ka (∼ ±13 years), marking the onset of a multi-centennial period of relatively reduced ISM, which was punctuated by at least two multi-decadal droughts between ∼ 3:9 and 4.0 ka. The latter stands out in contrast with some previous proxy reconstructions of the ISM, in which the 4.2 ka event has been depicted as a singular multicentennial drought.
UR - http://www.scopus.com/inward/record.url?scp=85057745806&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85057745806&partnerID=8YFLogxK
U2 - 10.5194/cp-14-1869-2018
DO - 10.5194/cp-14-1869-2018
M3 - Article
AN - SCOPUS:85057745806
SN - 1814-9324
VL - 14
SP - 1869
EP - 1879
JO - Climate of the Past
JF - Climate of the Past
IS - 12
ER -