Frequency and dynamics of millennial-scale variability during Marine Isotope Stage 19: Insights from the Sulmona Basin (central Italy)

Abstract

Among past interglacial periods, Marine Isotope Stage (MIS) 19 is particularly interesting because its orbital geometry is very similar to that of the present interglacial. Here we present a high-resolution (subcentennial) multiproxy record covering the ca. 790-770 ka interval, i.e. the interglacial MIS 19c and the ensuing glacial inception of MIS 19b, from a lacustrine sediment sequence retrieved from the Sulmona Basin (central Italy). The record has an independent chronology based on radiometric dating of six volcanic ash layers, and the resulting age model has a mean associated uncertainty of ± 2.6 kyr. Variations in sediment geochemistry and mineralogy are interpreted in terms of past hydrological and 2 temperature changes. Several millennial and sub-millennial events of reduced precipitation are well expressed. Comparisons with continental and marine records from the mid-latitude and sub-polar North Atlantic suggest a broad spatial expression for the observed events. Events occurring within the interglacial are not clearly associated with changes in marine proxies in the Iberian Margin, although similarities with the record from the sub-polar North Atlantic can be recognized and tentatively linked to changes in local hydrography having a downstream effect amplified by changes in atmospheric circulation. During the glacial inception, however, changes in the Sulmona record are coherent with changes in North Atlantic records, with drier events likely associated with meltwater-induced intervals of AMOC weakening. An event at ca. 785.6 ka may also reflect oceanic changes caused by freshwater discharges from residual ice-sheets and an outburst flood, similar to the 8.2 ka event in the Holocene.

Millennial-scale changes in sea-surface temperature and productivity along the Kuroshio–Oyashio boundary during MIS-19 based on the radiolarian record from the Chiba composite section, central Japan

“…The millennial-scale climatic changes during MIS-19 can also be recognized in records from the northern Atlantic Ocean (Kleiven et al, 2011) and central Europe (Giaccio et al, 2015;Sánchez Goñi et al, 2016;Regattieri et al, 2019). Figure 5 shows the probable correlations between climate records for the Sulmona Basin in Italy (Giaccio et al, 2015;Regattieri et al, 2019) and the CbCS in Japan (this study). Synchronous trends in each region suggest the strength of a large-scale teleconnection over the northern hemisphere of the Arctic Oscillation (AO) associated with winter Aleutian Low intensity (Tompson and Wallace, 1998) during MIS-19.…”

“…Because Marine Isotope Stage (MIS)-19 is an interglacial period with an orbital composition of the Milankovitch cycle similar to that of the current interglacial (MIS-1), it is important to build a detailed understanding of the climatic features of this period for use in making future predictions (Tzedakis et al, 2012;Giaccio et al, 2015;Sánchez Goñi et al, 2016). High-resolution paleoclimatic records during have been documented from the North Atlantic (Kleiven et al, 2011;Ferretti et al, 2015;Sánchez Goñi et al, 2016), Indian Ocean (Valet et al, 2014), southern Europe (Giaccio et al, 2015;Simon et al, 2017;Nomade et al, 2019;Regattieri et al, 2019), Japan (Hyodo et al, 2017;Suganuma et al, 2018;Haneda et al, 2020), Lake El'gygytgyn (Wennrich et al, 2014), Lake Baikal (Prokopenko et al, 2006), and Antarctica (Jouzel et al, 2007). The amplitudes and timing of millennial-scale variations of these paleoclimatic records tend to be synchronized among areas suggesting a global climatic teleconnection (Tzedakis et al, 2012;Nomade et al, 2019).…”

Millennial-scale changes in sea-surface temperature and productivity along the Kuroshio–Oyashio boundary during MIS-19 based on the radiolarian record from the Chiba composite section, central Japan

“…The millennial-scale climatic changes during MIS-19 can also be recognized in records from the northern Atlantic Ocean (Kleiven et al, 2011) and central Europe (Giaccio et al, 2015;Sánchez Goñi et al, 2016;Regattieri et al, 2019). Figure 5 shows the probable correlations between climate records for the Sulmona Basin in Italy (Giaccio et al, 2015;Regattieri et al, 2019) and the CbCS in Japan (this study). Synchronous trends in each region suggest the strength of a large-scale teleconnection over the northern hemisphere of the Arctic Oscillation (AO) associated with winter Aleutian Low intensity (Tompson and Wallace, 1998) during MIS-19.…”

“…Plot showing the relationship between summer SST and Tr in the northwestern Pacific based on the dataset from Matsuzaki and Itaki (2017). Probable correlations of paleo climate records between Sulmona Basin in Italy (Giaccio et al, 2015;Regattieri et al, 2019) and the CbCS in Japan (this study).…”

“…Millennial-scale fluctuations in the surface water temperature during MIS-19 can be correlated with European climate changes (Giaccio et al, 2015;Sánchez Goñi et al, 2016;Regattieri et al, 2019), and these are thought to have emerged as a result of atmospheric circulation teleconnection over a wide area. However, there are limited reports of high-resolution analysis in MIS-19, and it is expected that detailed teleconnection mechanisms will be elucidated by comparing analysis results over wide geographic areas.…”