The western Antarctic Peninsula - A hotspot in recent and past climate variability
Contact: Dr. Donata Monien (now at ZMT Bremen)
The Western Antarctic Peninsula (WAP) region is one of the most sensitive and dynamic areas of the earth, where ecological and cryospheric systems respond rapidly to climatic changes. During the past 60 years a rapid regional warming and a concomitant glacier retreat were observed, affecting the coastal ecosystem by turbid meltwaters and contributing to global sea level rise. Furthermore, the occurrence of new ice-free areas may promote chemical weathering and soil formation on previously ice-covered bedrocks and in consequence these areas could act as iron source for fertilizing the Southern Ocean.
Currently, we focus on unrevealing recent climate changes and iron input (IMCOAST sub-project IP-5) and analogous climatic scenarios in the past (DFG funded project BR 775/25-1). The overarching goal of our study is to assess whether the documented temperature increase and associated glacier retreat at WAP is reflected in the sedimentary record and whether such episodes have occurred within the Holocene before. Therefore, we intend to characterize and quantify the particulate (SPM) and dissolved load of glacial meltwaters draining into Potter Cove, King George Island, by inorganic geochemical methods (major and minor elements, nutrients). According to these analyses, the results will help to identify recent effects of glacial melt on the ecosystem, e.g. is meltwater input prohibiting or supporting marine microorganism growth. The extent of meltwater drainage and SPM input will be investigated by analyzing SPM and surface sediments from Potter Cove. Based on provenance analyses we will document whether the material introduced into this bay is evenly distributed and uniform in composition and if specific source areas can be distinguished by their chemical signature. Additionally, it will be studied whether the reported increase in SPM may be quantified by determining sediment accumulation rates with 210Pb. Furthermore, quantitative SPM and sediment investigations will help to estimate the particle export of the region to the Southern Ocean. Longer sediment cores Maxwell Bay may moreover serve as archives for the climatic and paleoenvironmental development of this area during the Late Holocene - the last century in particular - and will be analyzed at high temporal resolution. In cooperation with the British Antarctic Survey sediments from lakes located at the Fildes and Potter Peninsula will further be used as reference sites.
- This study forms part of the project „Rapid Climate Change at the Western Antarctic Peninsula: Chemical Flux Change and Environmental Consequences“ and will be conducted in close cooperation with the project „Fe and Mn in Antarctic bivalves: Indicators of change in near-shore biogeochemistry?“ by Dr. Doris Abele from the Alfred Wegener Institute, Bremerhaven (DFG SPP Antarktis 2009-2012).
- Additionally our work is embedded in the multinational project “Impact of climate induced glacial melting on marine coastal systems in the western Antarctic Peninsula region” (IMCOAST). On a subproject-coordinated level this study combines different physico-hydrographical, sedimentological, geochemical and biological proxies to investigate past, ongoing and future climate related changes of land ice masses and sedimentary run-off and their effects on coastal benthic and pelagic ecosystems in the King George Island coastal area. This international research programme features a multidisciplinary approach involving geo- and biological sciences, field investigations, remote sensing and modelling, as well as knowledge of the hydrographical and biological history of the marine coastal ecosystems of the Western Antarctic Peninsula region (http://www.imcoast.eu, EU-FP7 funded project 2010-2013).
- A recently funded exchange and training project “Interdisciplinary Modelling of Climate Change on Coastal Western Antarctica - Network for Staff Exchange and Training” (IMCONet, EU-FP7 IRSES funded project, 2013-2017) will benefit from the results achieved in the two other projects.
POIGNER, H., MONIEN, P., MONIEN, D., KRIEWS, M., BRUMSACK, H.-J., WILHEMS-DICK, D. & ABELE, D. (submitted) Influence of the pore water geochemistry on Fe and Mn assimilation in Laternula elliptica at King George Island (Antarctica). Estuarine Coastal and Shelf Science.
HUSMANN, G., ABELE, D., MONIEN, D., MONIEN, P., KRIEWS, M. & PHILIPP, E.E.R. (2012). The influence of sedimentation on metal accumulation and cellular oxidative stress markers in the Antarctic bivalve Laternula elliptica. Estuarine, Coastal and Shelf Science, 10.1016/j.ecss.2012.06.003.
WATCHAM, E.P., BENTLEY, M.J., HODGSON, D. A., ROBERTS, S.J., FRETWELL, P.T., LLOYD, J.M., LARTER, R.D., et al. (2011). A new Holocene relative sea level curve for the South Shetland Islands, Antarctica. Quaternary Science Reviews, 30, 3152–3170, 10.1016/j.quascirev.2011.07.021.
MONIEN, P., SCHNETGER, B., BRUMSACK, H.-J., HASS, H.C. & KUHN, G. (2011). A geochemical record of late Holocene palaeoenvironmental changes at King George Island (maritime Antarctica). Antarctic Science, 23, 255–267, Doi 10.1017/S095410201100006x.
HASS, H.C., KUHN, G., MONIEN, P., BRUMSACK, H.-J. & FORWICK, M. (2010). Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands, West Antarctica. Geological Society, London, Special Publications, 344, 243–260, 10.1144/SP344.17.