Late Holocene palaeoceanography in Van Mijenfjorden, Svalbard

Abstract

Based on detailed stratigraphical analysis of sediment cores spanning the last ca. 4000 calendar years, we reconstruct the palaeoceanograhic changes in the fiord Van Mijenfjorden, western Svalbard. Benthic foraminiferal δ18O indicate a gradual reduction in bottom water salinities between 2200 BC and 500 BC. This reduction was probably mainly a function of reduced inflow of oceanic water to the fiord, due to isostatic shallowing of the outer fiord sill. Stable salinity conditions prevailed between 500 BC and. 1300 AD. After the onset of a major glacial surge of the tidewater Paulabreen (Paula Glacier) system (PGS) around 1300 AD, there was a foraminiferal faunal change towards glacier proximal conditions, associated with a slight bottom water salinity depletion. During a series of glacial surges occuring from 1300 AD up the present salinity in the fiord has further decreased, corresponding to a δ18O depletion of 0.5 %o. This salinity decrease corresponds to the period when the PGS lost an equivalent of 30 – 40 % of its present ice volume, mainly through calving in the fiord.

Holocene glacial evolution of Mohnbukta in eastern Spitsbergen

“…Previously it has been suggested that many of the Svalbard glaciers reached their postglacial maxima in the late Holocene, most notably at the end of the LIA (Salvigsen et al 1992;Svendsen & Mangerud 1997;Sletten et al 2001;Humlum et al 2005). However, several Svalbard glaciers are suggested to have experienced pre-LIA advances (Salvigsen et al 1990;Ronnert & Landvik 1993;Werner 1993;Andersson et al 2000;Hald et al 2001;Lønne 2005;Kempf et al 2013;Reusche et al 2014). The data from Mohnbukta support these findings and indicate that a glacial advance, more extensive than the LIA advance, has also taken place on the east coast of Spitsbergen.…”

“…A few Svalbard glaciers, mainly on the west coast of Spitsbergen, have been suggested to experience surgetype advances prior to the historical period, based on dates from marine sediment cores and terrestrial glacial deposits (Punning et al 1976;Hald et al 2001;Kempf et al 2013). Nathorstbreen in Van Keulenfjorden experienced a surge-type advance between 2790-2610 cal.…”

“…a BP (Kempfet al 2013) and Paulabreen in the nearby Van Mijefjorden has been suggested to have surged around 650 cal. a BP (Hald et al 2001) as well as during the early Holocene, sometime between 8550-7850 cal. a BP (Punning et al 1976).…”

“…The data from Mohnbukta support these findings and indicate that a glacial advance, more extensive than the LIA advance, has also taken place on the east coast of Spitsbergen. Interestingly, very few of the suggested pre-LIA advances have been assigned a surge origin (Hald et al 2001;Kristensen et al 2009;Kempf et al 2013).…”

Interactions of Arctic and Atlantic water‐masses and associated environmental changes during the last millennium, Hornsund (SW Svalbard)

“…Several marine sedimentary records span the Holocene history of the area (Elverhi et al 1995;Hald et al 2001Hald et al , 2004Hald et al , 2007Slubowska et al 2005;Forwick & Vorren 2007;Rasmussen et al 2007; Slubowska-Woldengen et al 2007). Their resolution for the last millennium is relatively low, but some records have revealed abrupt environmental shifts (e.g.…”