Proglacial landscape evolution across the Antarctic Peninsula with Holocene climate change

Lead Research Organisation: University of Leeds
Department Name: Sch of Geography

Abstract

The ice sheet margin around the Antarctic Peninsula receded rapidly from its Last Glacial Maximum (LGM) position on the continental shelf edge ~ 18 ka (Davies et al., 2012) to a position towards the head of fjords, and in some cases onto land. These former outlet glacier margins are marked by prominent (tens of km long) lateral moraine ridges along the major fjords. Coincidentally, sea level changes and isostasy created raised beaches, multiple shorelines and perched deltas (e.g. Fretwell et al., 2010). However, the rates and primary drivers of landscape evolution in NE Antarctic Peninsula in response to natural climate change are otherwise little known and are contentious, at least partly due to a lack of in situ observations, the variety of glaciation styles and complex paraglacial adjustments during and after the deglaciation.

The Pleistocene-Holocene transition along the northern tip of Antarctic Peninsula is connected with a significant and rapid climate warming between 13 and 12 ka BP and predominant early Holocene hypsythermal conditions continuing until 9.5 ka BP (Mulvaney et al., 2012) resulting in consequent ice shelf collapse and glacier retreat (e.g. Bentley et al., 2005). A number of mid and late-Holocene advances have been proposed from a handful of sites (Hjort et al., 1997; Bentley et al., 2009; Carrivick et al., 2012), but there is an absence of widespread evidence for a Little Ice Age across the Antarctic Peninsula (Mulvaney et al., 2012).

The opportunity to examine the composition, functioning and evolution of the ice-free proglacial parts of the Antarctic Peninsula is potentially extremely valuable, to yield new insights into the extent to which glaciers and their associated processes have shaped the landscape. These systems deliver vast volumes of meltwater and sediment to the bays and fjords of the Antarctic Peninsula (Griffith and Anderson, 1989; Kavan et al., 2017) and ultimately to the Southern Ocean. These water and sediment fluxes are controlled by glacier fluctuations (e.g. Diekmann et al., 2000; Evans et al., 2005) and in turn strongly influence mineral exports (e.g. Bown et al., 2018) and primary production and hence food webs in the Southern Ocean (e.g. Wefer and Fischer, 1991).

This project aims to assess landscape evolution across the Antarctic Peninsula during the Holocene by using a novel combination of high-resolution 3D geospatial analysis; most likely including datasets such as the recently released REMA DEM and Planet imagery, and field surveys of geomorphology, sedimentology and with geochronological ambitions. It will develop the methods and analysis of Carrivick et al. (2018) as applied to the proglacial areas of the central European Alps. Field surveys will be based on the Ulu Peninsula of James Ross Island, the second largest ice free area in the whole of Antarctica Peninsula, with the support and logistics of the Czech J.G.Mendel Station. Combining these skills and approaches will permit local process-based interpretations and a regional picture to be assembled of Holocene landscape development across the Antarctica Peninsula. Questions concerning sediment fluxes from glaciated versus deglaciated catchments, geomorphological structure-composition (landforms), geomorphological functioning (e.g. connectivity) and terrestrial-fjord linkages will be addressed.

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
NE/S007458/1 01/09/2019 30/09/2027
2444876 Studentship NE/S007458/1 01/10/2020 31/03/2024 Christopher Stringer