Robert Turnewitsch

T:   +44 (0)1631 559 265

F:   +44 (0)1631 559 001

E:   robert.turnewitsch@sams.ac.uk

Research Interests:

Deep-Sea Landscapes – Fluid Dynamics and Sediment Geochemistry

The sediment-covered seafloor in the deep sea is topographically structured on spatial scales of millimeters (e.g., animal burrows) up to thousands of kilometers (continental margins, abyssal plains, mid-ocean ridges). For these very small and very large scales the impact of topographic heterogeneities on the environment has been relatively well studied. For spatial scales in the medium range of kilometers up to a few tens of kilometers, however, there is little information. On this medium space scale mainly topographic features such as abyssal hills, seamounts, fracture-zone valleys and canyons structure the global seafloor. Residual flow, tides and internal waves (tides) interact with such kilometer-scale topography. These interactions lead to hydrodynamic patterns that would not exist without the presence of these topographies and add even more structure and complexity to the environment. From here two interdisciplinary research foci arise:

(1) How do flow / topography interactions vary with the topographic geometry relative to the intensity of steady inflow, stratification, geographical latitude, tidal forcing, tidal excursion, water depth and the internal-wave characteristic?

(2) How are these flow / topography interactions reflected in

·           the sedimentary record?

·           biogeochemical fluxes across the sediment-water interface?

·           organic matter decomposition and preservation?

·           ecosystem structure and dynamics?

Selected recent and ongoing initiatives:

TopoDeep  –  Impact of the Geometry of Submarine Landscapes on Deep-Sea Biogeochemistry

Oceans 2025 (Themes 1 and 3)

OASIS (OceAnic Seamounts: an Integrated Study)

Teaching / Supervising:

Module leader    -    Marine Pollution (H3)

Contributions to the following modules: Sediment Processes, Defining the Marine Carbon Cycle, Marine Conservation

PostDoc  -  Florian Peine (University of Rostock)

Former PhD students    -    Paul Morris (NOC); Sandy Thomalla (University of Cape Town)

Publications:

Turnewitsch, R., Pohl, C. (in prep.) An estimate of the efficiency of the dissolved-phosphate trap at a brackish water-column redoxcline

Waniek, J.J., Tyrrell, T., Schiebel, R., Powell, S., Schulz-Bull, D., Turnewitsch, R. (submitted). Autumn bloom or stirring up of deep chlorophyll in the temperate NE Atlantic?

Peine, F., Turnewitsch, R., Mohn, C., Reichelt, T., Springer, B.M., Kaufmann, M. (2009). The importance of tides for sediment dynamics in the deep sea – Evidence from the particulate-matter tracer 234Th in deep-sea environments with different tidal forcing. Deep-Sea Research I 56, 1182-1202.

Forster, S., Turnewitsch, R., Powilleit, M., Werk, S., Ziervogel, K., Kersten, M. (2009). Thorium-234 derived information on particle residence times and sediment deposition in shallow waters of the south-western Baltic Sea. Journal of Marine Systems 75, 360-370.

Turnewitsch, R., Reyss, J.-L., Nycander, J., Waniek, J, Lampitt, R.S. (2008). Internal tides and sediment dynamics in the deep sea – Evidence from radioactive 234Th/238U disequilibria. Deep-Sea Research I, 55, 1727–1747.

Lampitt, R.S., Boorman, B., Brown, L., Lucas, M., Salter, I., Sanders, R., Saw, K., Seeyave, S., Thomalla, S.J., Turnewitsch, R. (2008). Particle export from the euphotic zone: Estimates using a novel drifting sediment trap, 234Th and new production. Deep-Sea Research I, 55, 1484-1502.

Thomalla, S.J., Poulton, A.J., Sanders, R., Turnewitsch, R., Holligan, P., Lucas, M. (2008). Variable export fluxes and efficiencies for calcite, opal, and organic carbon in the Atlantic Ocean: A ballast effect in action? Global Biogeochemical Cycles 22, GB1010, doi:10.1029/2007GB002982.

Morris, P.J., Sanders, R., Turnewitsch, R., Thomalla, S.J. (2007). 234Th derived particulate organic carbon export compared to new production from an island induced phytoplankton bloom in the Southern Ocean. Deep-Sea Research II 54, 2208–2232.

Turnewitsch, R., Springer, B.M., Kiriakoulakis, K., Vilas Español, J.C., Arístegui, J., Wolff, G., Peine, F., Werk, S., Graf, G., Waniek, J. (2007). Determination of the concentration of particulate organic carbon (POC) in seawater: the relative methodological importance of artificial organic carbon gains and losses in two glass-fiber-filter-based techniques. Marine Chemistry 105, 208-228.

Turnewitsch, R., Domeyer, B., Graf, G. (2007). Experimental evidence for an effect of early-diagenetic interaction between labile and refractory marine sedimentary organic matter on nitrogen dynamics. Journal of Sea Research 57, 270-280.

Thomalla, S., Turnewitsch, R., Lucas, M., Poulton, A. (2006). Particulate organic carbon export from the North and South Atlantic: the 234Th/238U disequilibrium approach. Deep-Sea Research II 53, 1629-1648.

Rutgers van der Loeff, M.M., Sarin, M.M., Baskaran, M., Benitez-Nelson, C., Buesseler, K.O., Charette, M., Dai, M., Gustafsson, Ö., Masque, P., Morris, P., Orlandini, K., Rodriguez y Baena, A., Savoye, N., Schmidt, S., Turnewitsch, R., Vöge, I., Waples, J. (2006). A review of present techniques and methodological advances in analyzing 234Th in aquatic systems. Marine Chemistry 100, 190-212.

Turnewitsch, R., Reyss, J.-L., Chapman, D.C., Thomson, J., Lampitt, R.S. (2004). Evidence for a sedimentary fingerprint of an asymmetric flow field surrounding a short seamount. Earth and Planetary Science Letters (Frontiers Article) 222(3-4), 1023-1036.

Turnewitsch, R., Graf, G. (2003). Variability of particulate seawater properties related to bottom mixed layer-associated internal waves in shallow water on a time scale of hours. Limnology and Oceanography 48(3), 1254-1264.

Turnewitsch, R., Springer, B.M. (2001). Do bottom mixed layers influence 234Th dynamics in the abyssal near-bottom water column? Deep-Sea Research I 48(5), 1279-1307.

Turnewitsch, R., Witte, U., Graf, G. (2000). Bioturbation in the abyssal Arabian Sea: influence of fauna and food supply. Deep-Sea Research II 47(14-16), 2877-2911.

Career history:

2006 -               Lecturer in Marine Geochemistry, Scottish Association for Marine Science, UK

2006                 Research Fellow, Baltic Sea Research Institute Warnemünde (IOW), Germany

2002 - 2006       NOC Research Fellow, National Oceanography Centre, Southampton, UK

2000 - 2001       Post-Doc, Rostock University, Germany

Education:

IfM-GEOMAR, Germany; degree: PhD (Dr rer nat magna cum laude)

University of Kiel, Germany; degree: MSc with distinction (Diplom mit Auszeichnung)

University of Kiel, Germany; degree: BSc (Vordiplom)