2016 Ocean Sciences – GEOTRACES sessions

2016 Ocean Sciences Meeting
(21-26 February 2016, New Orleans, Louisiana, USA, http://osm.agu.org/2016/) 

GEOTRACES-related sessions (see session descriptions below):

Atmospheric deposition and ocean biogeochemistry
Primary Chair: Ana M Aguilar-Islas, University of Alaska Fairbanks
Chairs: Clifton S Buck and Meredith Galanter Hastings
Monday, February 22, 2016, 228-230: 8-10 am, Poster Hall: 4-6 pm

The role of particles in the cycling of trace elements and their isotopes in the ocean
Primary Chair: Hélène Planquette, LEMAR, CNRS
Chairs: Phoebe J Lam and Benjamin S. Twining
Tuesday, February 23, 2016, 228-230: 8-10 am, 2-4 pm, Poster Hall: 4-6 pm

Trace Elements and Isotopes at the Interfaces of the Atlantic Ocean
Primary Chair: Geraldine Sarthou, LEMAR UMR 6539 CNRS UBO IRD IFREMER, IUEM
Chairs: Edward A Boyle, Gideon Mark Henderson and Micha J.A. Rijkenberg
Monday, February 22, 2016, 228-230: 10:30 am-12:30 pm, Poster Hall: 4-6 pm

Trace Metal Bioavailability and Metal-Microorganism Interactions
Primary Chair: Julia M Gauglitz, Woods Hole Oceanographic Institution
Chairs: Randelle Bundy and Jill N Sutton
 Thursday, February 25, 2016, 228-230: 8-10 am, Poster Hall: 4-6 pm

Trace metal speciation in seawater: measurements, modelling and impact on marine biogeochemistry
Primary Chair: David R Turner, University of Gothenburg
Chairs: Stan MG van den Berg, Sylvia Gertrud Sander, Kristen N Buck, Rachel Shelley, Peter L Morton, Christian Schlosser and Eric P. Achterberg
Wednesday, February 24, 2016, 228-230: 8-10 am, 2-4 pm, Poster Hall: 4-6 pm

Variability in Southern Ocean Productivity over Different Timescales
Primary Chair: Alessandro Tagliabue, University of Liverpool
Chairs: Philip Boyd, Eugene W Domack and Amy Leventer
Thursday, February 25, 2016, Poster Hall: 4-6 pm
Friday, February 26, 2016, 215-216: 10:30 am-12:30 pm

GEOTRACES sessions descriptions:

Atmospheric deposition and ocean biogeochemistry

Monday, February 22, 2016, 228-230: 8-10 am, Poster Hall: 4-6 pm

Primary Chair: Ana M Aguilar-Islas, University of Alaska Fairbanks, Fairbanks, AK, United States
Chairs: Clifton S Buck, Skidaway Institute of Oceanography, Savannah, GA, United States and Meredith Galanter Hastings, Brown Univ-Geological Sciences, Providence, RI, United States

Session Description:

Atmospheric deposition of marine, lithogenic and anthropogenic aerosols is an important transport pathway for nutrients and contaminants to the surface ocean. Constraining local, regional and global atmospheric deposition flux estimates and the bioavailability of aerosol-derived elements and compounds is essential for furthering understanding of ocean biogeochemistry. This transport pathway acts as an important chemical bridge between the lithosphere and hydrosphere linking major biogeochemical cycles. Aerosol emission, transport and deposition processes are, in part, a function of global change related to changes in land coverage, anthropogenic emissions and climate. Hence the study of ocean responses will improve our ability to predict future impacts. The GEOTRACES international program includes objectives related to the atmospheric input of trace elements and isotopes to accomplish its goal. Other programs, such as SOLAS and CLIVAR, continue to make significant contributions as well. This session invites contributions from studies of atmospheric deposition in the marine environment, including observations of atmospheric deposition fluxes, aerosol composition, aerosol fractional solubility, the fate of aerosol-derived compounds and the biological and chemical response to deposition within the surface ocean. Contributions from global and regional scale field observations, laboratory studies and modeling efforts are welcomed.

The role of particles in the cycling of trace elements and their isotopes in the ocean

Tuesday, February 23, 2016, 228-230: 8-10 am, 2-4 pm, Poster Hall: 4-6 pm

Primary Chair: Hélène Planquette, LEMAR, CNRS, Plouzané, France
Chairs: Phoebe J Lam, University of California Santa Cruz, Department of Ocean Sciences, Santa Cruz, CA, United States and Benjamin S. Twining, Bigelow Lab for Ocean Sciences, East Boothbay, ME, United States

Session Description:

A number of trace metals are thought to control marine ecosystem features and biological productivity. While trace elements in the dissolved phase have been the focus of many investigations, we are still largely ignorant of the large scale distribution of particulate trace elements and their size partitioning and chemical composition. The GEOTRACES program, which aims to provide a comprehensive view of the distribution of trace elements and their isotopes (TEIs) in the world’s oceans, is providing new insights on these aspects. Furthermore, there is a crucial need to understand the exchange mechanisms between particulate and dissolved pools, including adsorption, desorption, aggregation, precipitation, biological uptake and remineralization processes. This session seeks to bring together scientists interested in better constraining the role of ocean particles in the biogeochemical cycles of TEIs, in different oceanic environments, such as the continental shelves and slopes, the nepheloid layers, or the particle-poor regions of the open ocean. We invite abstracts on all aspects of oceanic particulate TEIs, through experimental, in situ and modeling approaches.

Trace Elements and Isotopes at the Interfaces of the Atlantic Ocean

Monday, February 22, 2016, 228-230: 10:30 am-12:30 pm, Poster Hall: 4-6 pm

Primary Chair: Geraldine Sarthou, LEMAR UMR 6539 CNRS UBO IRD IFREMER, IUEM, Plouzané, France
Chairs: Edward A Boyle, Massachusetts Institute of Technology, Earth Atmospheric and Planetary Sciences, Cambridge, MA, United States, Gideon Mark Henderson, University of Oxford, Earth Sciences, Oxford, United Kingdom and Micha J.A. Rijkenberg, Royal Netherlands Institute for Sea Research, Den Burg, Netherlands

Session Description:

Trace elements play a crucial role in the ocean. Some are toxic at high concentrations, others serve as essential micronutrients in the many metabolic processes active in marine organisms. Some trace elements and their isotopes (TEIs) are diagnostic and allow the quantification of specific oceanic mechanisms. Studying the biogeochemical cycles of TEIs is thus necessary to deepen our understanding of carbon and nutrient cycling, climate change, ocean ecosystems and environmental contamination. The Atlantic Ocean is one of the primary CO2 sinks of the world ocean and one of the most biologically productive. Recently, full-depth high resolution measurement campaigns, especially in the framework of the international GEOTRACES program, have revolutionized our understanding of the TEI cycling in the Atlantic Ocean. However, processes occurring at the oceanic interfaces are very complex and need more attention. The aim of this session is to increase our understanding of the exchange of TEIs at the interfaces between the ocean and i) the atmosphere, ii) the continents (e.g. by rivers and groundwater), iii) the marine sediments, and iv) the ridges. We will particularly encourage contributions dealing with interdisciplinary studies, with new insights gained by application of state-of-the-art analytical tools and modeling approaches.

Trace Metal Bioavailability and Metal-Microorganism Interactions

Thursday, February 25, 2016, 228-230: 8-10 am, Poster Hall: 4-6 pm

Primary Chair: Julia M Gauglitz, Woods Hole Oceanographic Institution, Marine Chemistry and Geochemistry, Woods Hole, MA, United States
Chairs: Randelle Bundy, Woods Hole Oceanographic Institution, Marine Chemistry and Geochemistry, Woods Hole, MA, United States and Jill N Sutton, IUEM/UBO, Technopôle Brest-Iroise, Place Nicolas Copernic, Plouzané, France

Session Description:

The distributions of trace elements in the marine environment are undeniably linked to biological processes. Low concentrations or low bioavailability of trace metals in the water column can lead to micronutrient limitation and stress, while greater availability may increase biological demand and enhance the growth of microorganisms. Recent advances in high throughput biological techniques, including “omics”, as well as high-resolution geochemical data from the GEOTRACES program (www.geotraces.org) has lead to a wealth of new data. However, meaningful interpretation of these data often still relies on process studies, incubation-based experimental work, or the culturing of representative or novel organisms. This session invites contributions on every scale of metal-microorganism interactions, ranging from small-scale mechanistic work to large-scale biogeochemical cycle studies. We encourage abstracts that investigate trace metal acquisition strategies, cellular metabolism, chemical speciation and bioavailability, and/or studies that link trace metal and biological water column data. Presentations that strive to better understand the biological control exerted on the distribution of trace elements in the marine environment are especially encouraged.

Trace metal speciation in seawater: measurements, modelling and impact on marine biogeochemistry

Wednesday, February 24, 2016, 228-230: 8-10 am, 2-4 pm, Poster Hall: 4-6 pm

Primary Chair: David R Turner, University of Gothenburg, Gothenburg, Sweden
Chairs: Stan MG van den Berg, University of Liverpool, Liverpool, L69, United Kingdom, Sylvia Gertrud Sander, University of Otago, Dunedin, New Zealand, Kristen N Buck, University of South Florida Tampa, Tampa, FL, United States, Rachel Shelley, LEMAR/UBO, Brest, France, Peter L Morton, Florida State University, Department of Earth, Ocean, and Atmospheric Science, Tallahassee, FL, United States, Christian Schlosser, GEOMAR Helmholtz Centre for Ocean Research Kiel, Chemical Oceanography, Kiel, Germany and Eric P. Achterberg, GEOMAR Helmholtz Centre for Ocean Research Kiel.

Session Description:

Global change processes, in particular ocean acidification, are changing the chemistry of seawater. The carbon dioxide system and trace metal speciation are expected to be among the chemical components of seawater most strongly affected by global change processes. The distribution and identity of organic metal complexing ligands in the marine system, and modelling of the chemical speciation using updated parameters, play an important role in understanding the changes that take place and in projecting future changes. This session builds on two SCOR working groups : WG139 which is focused on organic metal-binding ligands; and WG145 which is focused on modelling metal speciation in seawater. One aspect of metal speciation that is receiving particular attention is the bioavailability of trace metals, with extensive measurement programmes on the complexation of bioactive trace metals currently under way, in particular within the GEOTRACES program. This work is producing exciting new field data that will benefit from improved speciation modelling and additional measurements. We invite contributions on the identification, distribution and provenance of organic ligands in the marine environment, the modelling of inorganic and organic metal speciation, and linkages of trace metal speciation with ocean acidification and other factors of climate change.

GEOTRACES-related sessions descriptions:

Variability in Southern Ocean Productivity over Different Timescales

Thursday, February 25, 2016, Poster Hall: 4-6 pm
Friday, February 26, 2016, 215-216: 10:30 am-12:30 pm

Primary Chair: Alessandro Tagliabue, University of Liverpool, Liverpool, United Kingdom
Chairs: Philip Boyd, IMAS, ACE-CRC, University of Tasmania, Hobart, Australia, Eugene W Domack, University of South Florida St. Petersburg, St Petersburg, FL, United States and Amy Leventer, Colgate University, Geology, Hamilton, NY, United States

Session Description:

Southern Ocean productivity plays an important role in regulating marine resources, ocean biogeochemistry and the global carbon cycle. Canonically, variations in iron supply and demand are thought to regulate the variations in phytoplankton productivity. However, via the actions of ocean physics, the Southern Ocean also encounters substantial fluctuations across space and time in temperature, sea ice and glacial ice dynamics and the availability of light and/or macro- and micro-nutrients. How these regulatory factors act individually and in combination to shape the dynamics of biological activity across food webs in different Southern Ocean regions and different timescales is not well understood. This hampers our ability to project with confidence how future environmental change will affect this important ecosystem. In particular we lack an understanding of how variations in the physical and/or biogeochemical environment are underpinned and connected to the broader picture of ecosystem structure, as well as wider biogeochemical feedbacks. We invite presentations from field, laboratory, remote sensing, modelling and paleo studies that seek to unravel the dynamics of the Southern Ocean marine ecosystem from a seasonal or decadal or millenial scale viewpoint. Efforts to combine insights across disciplines and scales from physics to biogeochemistry to ecosystems are actively encouraged.