Centennial to millennial climate variability in the far northwestern Pacific (off Kamchatka) and its linkage to the East Asian monsoon and North Atlantic from the Last Glacial Maximum to the early Holocene

Sergey A Gorbarenko,Min-Te Chen,Yanguang Liu,Aleksandr A Bosin,Galina Yu Malakhova,Xuefa Shi,Jianjun Zou

doi:10.5194/cp-13-1063-2017

Abstract

Abstract. High-resolution reconstructions based on productivity proxies and magnetic properties of core LV63-41-2 (off Kamchatka) reveal prevailing centennial productivity/climate variability in the northwestern (NW) Pacific from the Last Glacial Maximum (LGM) to the early Holocene (EH). The age model of the core is established by AMS 14C dating and by projections of AMS 14C data of the nearby core SO-201-12KL through correlation of the productivity proxies and relative paleomagnetic intensity. The resulting sequence of centennial productivity increases/climate warming events in the NW Pacific occurred synchronously with the East Asian summer monsoon (EASM) sub-interstadials during the LGM (four events), Heinrich Event 1 (HE1) (four events), Bølling–Allerød (B/A) warming (four events), and over the EH (four events). Remarkable similarity of the sequence of the NW Pacific increased-productivity events with the EASM sub-interstadials over the LGM-HE1 implies that the Siberian High is a strong and common driver. The comparison with the δ18O record from Antarctica suggests that another mechanism associated with the temperature gradient in the Southern Hemisphere may also be responsible for the EASM/NW Pacific centennial events over the LGM-HE1. During the B/A warming and resumption of the Atlantic Meridional Overturning Circulation (AMOC), clear synchronicity between the NW Pacific, EASM and Greenland sub-interstadials was mainly controlled by changes in the atmospheric circulation. During the EH the linkages between solar forcing, ocean circulation, and climate changes likely control the synchronicity of abrupt climate changes in the NW Pacific and North Atlantic. The sequence of centennial events recorded in this study is a persistent regional feature during the LGM-EH, which may serve as a template in high-resolution paleoceanography and sediment stratigraphy in the NW Pacific.

Highlights

Model simulations and proxy-based records have both led to contradictory results on the millennial-scale environmental variability in the northwestern (NW) Pacific and its underlying mechanisms during the last deglaciation
A decreased trend of productivity records at the interval of ∼ 230–190 cm is likely associated with the Younger Dryas (YD) cooling and the subsequent high productivity trend in the upper 190 cm is presumably related to the Holocene warming (Fig. 2)
We interpret that the climate became warmer in the NW Pacific during the B/A period, terminating the last glaciation, it reversed to the cooling during the Younger Dryas (YD) followed by the significant warming throughout the Holocene

Summary

Introduction

Model simulations and proxy-based records have both led to contradictory results on the millennial-scale environmental variability in the northwestern (NW) Pacific and its underlying mechanisms during the last deglaciation. These model and proxy studies suggested either in-phase relationships of deglacial variability between the North (N) Atlantic and NW Pacific (Caissie et al, 2010; Chikamoto et al, 2012; Kienast and McKay, 2001; Seki et al, 2002) or out-of-phase. The Siberian High (SH), an essential component of northern East Asian atmosphere system, significantly influences the East Asian winter monsoon (EAWM) (Wu and Wang, 2002), which in turn affects the environment of NW Pacific. The out-ofphase response, was proposed to be driven by a seesaw mechanism, with oceanic readjustments between the weakening of the Atlantic Meridional Overturning Circulation (AMOC) and the strengthening of the Pacific Meridional Overturning Circulation (Okazaki et al, 2010)

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