Geert-Jan Brummer

Geert-Jan Brummer

ROYAL NETHERLANDS INSTITUTE

FOR SEA RESEARCH

Postal address:

P.O. Box 59,

NL-1790 AB Den Burg (Texel)

The Netherlands

Visiting address:

Landsdiep 4

NL-1797 SZ ’t Horntje (Texel)

The Netherlands

Phone: (+31) (0)222-369300

Fax: (+31) (0)222-319674

PA120020

Room: C00 3, Dept: GEO

E-mail: Geert-Jan.Brummer

extension: @nioz.nl

Phone: (+31) (0)222-369442

Research Interests:

As a scientist at NIOZ, I pursue how sediments form on the sea floor, at present and during past climate change. Together with PhD-students and post-docs we carry out sea-going research on such topics as seasonal particle production by ocean plankton, current transport of bottom sediment and coral carbonate geochemistry in response to changing ocean-climate. We address research questions in collaborative projects, mainly in the Atlantic and Indian Ocean, sea-going and multidisciplinary.

· Sediment genesis: the pathways of production, transformation and accumulation fluxes of sedimentary matter, notably biogenic carbonates, silica and organic compounds.

· Ocean-climate change: anthropogenic and natural variability of biogeochemical cyling and thermohaline circulation; high-resolution paleoceanography.

· Planktonic foraminifera: biodiversity and population dynamics, seasonality and intermittency of export fluxes, isotope and chemical composition, dissolution and sediment mixing; proxy validation, evolutionary paleoceanography.

· Physical forcing mechanisms: stratification and mixing, eddy transports, thermo-haline circulation, re-suspension and sediment focussing.

Current research and projects:

In association with the Long-term Ocean Climate Observation-program we are active in sea-going research in important gateways for ocean circulation: Indian Ocean off Madagascar to address the effect of Mozambique eddies on the seasonal particle fluxes from the upper ocean across the biogeochemical sediment-water interface atmospheric and current forcing on deep ocean particle fluxes and modern to millennial-scale variability during past climate change.
Irminger Sea off Greenland to address the effects to atmospheric and current forcing on deep ocean particle fluxes, specifically deep convective mixing in winter, in relation to the climatic variability in Atlantic meridional overturning circulation.

There we look at modern ocean processes as they develop in response to anthropogenic climate change using moored instrumentation for time-series tracking down to the deep ocean floor. A wide array of marine techniques is coupled to geochemical analyses to develop and interpret the tracers for anthropogenic climate forcing (global warming, acidification, biotic responses, sea level change, ocean overturning). Bottom coring brings up the reactive sediment next to an archive of past changes in ocean-climate evolution, across ice ages and into deep geological time. Coral coring yields carbonate archives for ENSO-scale variability and monsoonal land run-off over the past centuries that can be tied to open ocean and continental records. Specific research aims are formulated within projects:

INATEX-B: Tracing past to modern Indo-Atlantic exchange in sedimentary records (2009-2012)

People involved: PostDoc (vacancy), Dr. G.J.A. Brummer (PI), Prof. Dr. H. Ridderinkhof (FYS), Prof. Dr. W.P.M. de Ruijter (UU-IMAU), Prof. Dr. D. Kroon (VU/Edinburgh), Prof. Dr. T.C.E. van Weering (VU/NIOZ).

Funding: NWO-ALW ZKO-Oceans

SINDOCOM: Southern Indian Ocean/Tropical Pacific teleconnections assessed by a joint coral-in situ ocean monitoring database (September 2006-2010)

People involved: C. Grove (PhD student), Dr. G.J.A Brummer (PI), Dr. H. Ridderinkhof (FYS); Dr. J. Zinke (VU), Prof. Dr. D. Kroon (VU), Prof. Dr. G. Davies (VU).

Funding: NWO-ALW Climate Change Program

Role of cyanobacteria in past biogeochemical cycling (2006-2009)

People involved: T. Bauersachs (Ph.D student), Prof. Dr. J.S. Sinninghe Damsté (promotor), Dr. S. Schouten, Dr. G.J. Brummer (MCG), Dr. E.C. Hopmans.

Funding: Darwin (NWO/NIOZ)

Temperature and salinity proxies of ocean thermohaline circulation and climate change: development and verification (November 2005-2009)

People involved: (PhD), Dr. G.J.A. Brummer (PI), Dr. S. Schouten (BGC) ; Prof. Dr. J. Bijma (AWI/IUB) and Bremen-partners

Funding: NEtherlands-BRemen Oceanography Cooperation-2, NIOZ/NWO.

EKP: Natural, climatic and anthropogenic change of the Berau Delta/Barrier Reef system: High-resolution coral proxy analysis of the modern environment and reconstruction on a seasonal to centennial timescale (2005-2012).

People involved: R. Nagtegaal (PhD), (post-doc), Dr G.J.A. Brummer (PI), Prof. Dr. T.C.E. van Weering, Prof. Dr. R. Bak (MEE/UvA), Prof. Dr. P. Hoekstra (UU)

Funding: WOTRO/KNAW/ICOMAR (East Kalimantan Programme for Coastal Zone Research Netherlands-Indonesia)

Variability of Atlantic Meridional Overturning Circulation (September 2005-2009)

People involved: (PhD), Dr. G.J.A. Brummer (PI), Dr. H. van Aken (FYS), Prof. Dr. T.C.E. van Weering; Dr. F.J.C. Peeters (VU), Dr. G.M. Ganssen (VU), Prof. Dr. H. Elderfield (Cambridge)

Funding: NERC-RCN-NWO trilateral programme RAPID2

Paleosalt: Development, calibration and application of independent salinity proxies (April 2006-2008)

People involved: Dr. M.T.J. van der Meer (postdoc BGC), Dr. S. Schouten (BGC-PI), Dr. G.J.A. Brummer (co-PI), U. Fallet (PhD), Prof. Dr. J. Bijma (AWI/IUB) and EU-partners.

Funding: ESF/NOW EUROCORES-EuroClimate

About:

Geert-Jan Brummer received his PhD-degree in Earth Sciences from the Free University Amsterdam (1988 with honours), the Royal Dutch Shell Award in 1986 and a Royal Academy of Sciences-fellowship at the Free University Amsterdam and Universität Tübingen (1988-1991). From 1991 he was a post-doc and project scientist at the Marine Chemistry dept. of Royal NIOZ until tenured in 1999, with “sediment trapping” as his expertise. He participated in 25-odd research cruises including 6 as the chief-scientist, he chaired the Steering Committee “Pelagia Around Africa 2000” organising a 6-month expedition with the NIOZ’s flagship across the Atlantic and Indian Ocean.

Geert-Jan Brummer acquired substantial contract and instrument grants for interdisciplinary ocean-going research, supervised 7 PhD-studies in collaboration with (inter-) national universities (VUA, UU, UE), and (co-) authored some 40-odd peer-reviewed publications including in Nature.