Quantitative reconstruction of palaeoclimate from pollen profiles in northeastern Japan and the timing of a cold reversal event during the Last Termination

Abstract

Yoshida, A. and Takeuti, S. 2009. Quantitative reconstruction of palaeoclimate from pollen profiles in northeastern Japan and the timing of a cold reversal event during the Last Termination.ABSTRACT: We reconstructed quantified palaeoclimate changes within two Japanese pollen profiles spanning the Last Termination (LT; 18-10 cal. ka) in an attempt to better understand past monsoon activity. The reconstructed winter climate at the Tashiro mire, which is strongly influenced by the Siberian air mass, showed a weak and a short-lived cooling event at 11.8-10.6 cal. ka. This event spans part of the Younger Dryas (YD) cooling event in the North Atlantic region, suggesting the latter influenced the Siberian high-pressure system. In contrast, the summer climate at the Komado mire, which is more influenced by the Pacific air mass, experienced a strong and a prolonged cooling event at 15.5-13.0 cal. ka. The latter event is broadly synchronous with the Antarctica Cold Reversal (ACR) event, and suggests that the Pacific high-pressure system weakened during this period. The pattern of climate change across East Asia shows that the YD event did not extend beyond the East Asian monsoon front, while the ACR event strongly affected the Pacific high-pressure system during the LT. We suggest the East Asian monsoon front is an important geo-climatic boundary between YD-like and ACR-like deglacial climate changes.

Pollen-based temperature reconstructions from Jeju island, South Korea and its implication for coastal climate of East Asia during the late Pleistocene and early Holocene

“…7c). This was much smaller than~18°C cooling in Greenland (Alley, 2000), but relatively similar to temperature reductions of 1-3°C reported from other pollen-based reconstructions in Lake Suigetsu (Nakagawa et al, 2003) and Tashiro mire (Yoshida and Takeuti, 2009) of Japan. SSTs reconstructed from marine sediment proxy were data also similar to our results: for example, the peak-to-peak amplitude between BA and YD was~2°C in the northern East China Sea (Kubota et al, 2010) and 2.5°C in the Okinawa Trough (Sun et al, 2005).…”

Changes in El Niño – Southern Oscillation (ENSO) conditions during the Greenland Stadial 1 (GS-1) chronozone revealed by New Zealand tree-rings

“…Although the GS-1 may have extended hemispheric-wide (Bronk Ramsey et al, 2012;Cooper et al, 2015;MacDonald et al, 2008;Wang et al, 2001;Williams et al, 2002;Yoshida and Takeuti, 2009), the spatial and temporal expression of climate during this period remains complex with an anti-phase trend in temperature between the high-latitudes postulated to be evidence for a bipolar ocean seesaw (Broecker, 1997;EPICA Community Members, 2006;Stocker and Johnsen, 2003;WAIS Divide Project Members, 2015).…”

Evidence for cryptic northern refugia in the last glacial period in Cryptomeria japonica

“…130 m per year (Tsukada, 1980). As this is too fast for this species due to its long regeneration time, cryptic refugia may have occurred in the northern part of Honshu where the boreal conifer forests existed during the LGM (Yoshida and Takeuti, 2009).…”