Home Page | Help | Contact | Log In | Search

Navigation

Physical and Geological Processes

SS24: Monitoring and Forecasting of Surface Current-Affected Phenomena in Coastal Regions — See Schedule

Conveners:Max Yaremchuk, Naval Research Laboratory, max.yaremchuk@nrlssc.navy.mil; Jeffrey Paduan, Naval Postgraduate School, paduan@nps.edu; Alexei Sentchev, Universite du Littoral, France, Alexei.Sentchev@univ-littoral.fr; Yves Barbin, Universite du Sud Toulon-Var, France, yves.barbin@univ-tln.fr

We invite presentations on the sea surface phenomena and Lagrangian tracking techniques in coastal environments based on remotely sensed observations of surface currents, modelling applications and data assimilation. This is a large topic of the applied oceanography in its own right, but it is also becoming clear that many larger-scale processes are essentially coupled with peculiarities of the coastal circulation, and those include local climate/weather, bioproductivity, marine pollution and many other issues related to the upper-ocean currents on regional scales. This is a rapidly developing area of the applied oceanographic research, and contributions based on the data analysis from the growing network of HF radar systems and regional modeling efforts are strongly encouraged.

SS25: Evolution of Coastal Change in the Northern Gulf of Mexico — See Schedule

Conveners:Christopher G. Smith, U.S. Geological Survey, cgsmith@usgs.gov; Lisa Osterman, U.S. Geological Survey, osterman@usgs.gov

The northern Gulf of Mexico continues to be besieged by both natural and man-made disasters. The environmental complexity of the northern Gulf of Mexico requires a “system- science” approach aimed at understanding the response of linked elements of coastal systems to multiple stressors and influences. An effective approach must develop information and understanding that addresses the regional scope of coastal change over multiple (oceanographic, ecologic, and geologic) time-scales. This session is broadly focused on how natural and anthropogenic processes (e.g., sea-level rise, storm events, climate, and land-use/land-change) have shaped the sedimentary record and geomorphic landscape of coastal regions along northern Gulf of Mexico over the last century or more.

SS30: Biological and Biogeochemical Responses to Human Impacts at the Sediment-Water Interface — See Schedule

Conveners:John Lehrter, EPA Gulf Ecology Division, lehrter.john@epa.gov; Katja Fennel, Dalhousie University, katja.fennel@dal.ca; Wally Fulweiler, Boston University, rwf@bu.edu; Roxane Maranger, University of Montreal, r.maranger@umontreal.ca

Human impacts to aquatic ecosystems often manifest at the sediment-water interface. Local and regional scale issues such as eutrophication, sedimentation and resuspension of inorganic and organic particles, toxic pollution, and over-fishing can have dramatic effects on benthic biological communities (ranging from microbial organisms to mega fauna) and induce feedbacks to the water column by altering biogeochemical processes. Recently, there is increasing awareness of compounding effects by global scale phenomena such as rising sea surface temperatures and ocean acidification. However, despite advancements in the theory, observation, and modeling of communities and biogeochemical processes at the sediment-water interface that have occurred over the last several decades, many regulating mechanisms are still poorly characterized. Hence, our ability to accurately predict and mitigate the impacts of human activities is hindered. This session invites investigators to present and discuss recent observational or modeling studies that add to our understanding of processes at the sediment-water interface. Presentations that integrate or synthesize across multiple spatial and temporal scales or levels of functional organization, genes to ecosystems, are encouraged. Non-research presentations that provide environmental policy perspectives and challenges, which may inform knowledge gaps and research needs, are also encouraged.

SS34: Biogeochemistry of Resuspended Sediments in Aquatic and Coastal Marine Environments — See Schedule

Conveners:John R. Helms, University of North Carolina Wilmington, helmsj@uncw.edu; Stephen Skrabal, University of North Carolina Wilmington, skrabals@uncw.edu; G. Brooks Avery, University of North Carolina Wilmington, averyg@uncw.edu; Ralph Mead, University of North Carolina Wilmington, meadr@uncw.edu

Sediment-water interactions during resuspension events can significantly impact a number of biogeochemical processes such as trace metal mobilization, nutrient and organic matter cycling, and release of anthropogenic contaminants. We invite papers on any biogeochemical aspect of sediment resuspension in coastal marine and aquatic environments. In particular we encourage contributions on how these processes might be influenced by global climate change (e.g. rising sea level) and land use changes.

SS48: Geochemical Consequences of Advection in Aquatic Sediments — See Schedule

Conveners:Andreas Brand, Eawag, Surface Water Group, andreas.brand@eawag.ch; Joerg Lewandowski, IGB Berlin -Ecohydrology group, lewe@igb-berlin.de; Gunnar Nuetzmann, IGB Berlin -Ecohydrology group, nuetzmann@igb-berlin.de; Christof Meile, Department of Marine Sciences, University of Georgia; cmeile@uga.edu

Porewater advection is critical for the understanding of early diagenesis in many aquatic settings. Some of these processes such as wave-induced porewater advection and the pumping activity of animals such as Arenicola marina have been closely investigated in marine environments. In addition, recent studies suggest that porewater advection is also a key process in limnic sediments. For example, tube dwelling fauna can induce porewater advection in the sediment surrounding their burrows due to their pumping activity, and porewater advection can become the dominant transport mechanism in sediments close to the thermocline in lakes with intense seiche activity. Furthermore, groundwater discharge can be the dominant transport mechanism in the open water – sediment – groundwater discharge transition zone. Since sediments are typically highly reactive, the turnover rates of organic carbon, nutrients, oxygen and other electron acceptors are tightly coupled to the transport processes which govern the supply of chemical compounds. In this session we aim to discuss novel approaches ranging from experimental investigations in the laboratory and in situ at various scales to numerical studies which investigate the impact of advection on biogeochemistry.

SS51: Iron, Carbon Cycling, and Ecosystem Dynamics in the Southern Ocean — See Schedule

Conveners:Stephane Blain, Universite Pierre et Marie Curie, stephane.blain@obs-banyuls.fr; Queguiner, Universite d'Aix-Marseille, bernard.queguiner@univ-amu.fr; Strass, Alfred Wegener Institute for Polar and Marine Research, Volker.strass@awi.de; Dieter Wolf-Gladrow, Alfred Wegener Institute for Polar and Marine Research, Dieter.Wolf-Gladrow@awi.de

In the macronutrient-rich waters of the Southern Ocean, the biological pump of CO2 is likely controlled by the supply and bioavailability of iron. Through diverse interactions, iron limitation causes co-limitations principally by the light regime or by silicon. These processes are themselves modulated by the biological couplings in the food webs, and iron availability drives the functional structure and the biodiversity within the Southern Ocean ecosystems. Iron impacts the coupling between the different biogeochemical cycles with feedbacks on climate or on the productivity of adjacent ocean basins, possibly affecting the global carbon cycle. Resolving this complex multi-faceted story requires a large international effort which is underway. This session aims to bring together the most recent findings on the following issues: the impact of iron supply on carbon sequestration and atmospheric CO2 drawdown, the interaction between iron availability and the structure, biodiversity, and functioning of pelagic ecosystems, the identification of iron sources and transport pathways, the transformations of iron mediated by biotic or abiotic processes, and the coupling/decoupling between iron and major nutrient biogeochemical cycles. We invite submissions addressing any of these topics, either obtained from the most recent field studies (such as KEOPS2, or Eddy Pump), modeling studies or re-analysis of relevant previous observations.

SS56: Carbon Fluxes in Aquatic Ecosystems at Catchment, Regional and Continental Scales — See Schedule

Conveners:Edward Stets, U.S. Geological Survey, estets@usgs.gov; Sebastian Sobek, Uppsala University, sebastian.sobek@ebc.uu.se; Cory McDonald, U.S. Geological Survey, cmcdonald@usgs.gov

Quantifying carbon fluxes in freshwater aquatic ecosystems provides insights into basin wide ecological and geochemical processes, and is critical to understanding past, present, and projected changes throughout the basin. Inland aquatic systems process carbon rapidly and need to be considered in order to accurately estimate net ecosystem production on large scales. Development of aquatic carbon flux estimates at large spatial scales (catchment, regional and global) is an area of active research in the aquatic biogeochemical community. Greater knowledge of the processes driving carbon fluxes as well as spatial and temporal variability in these estimates has been gained. This session will focus on large-scale carbon flux estimates in inland and coastal aquatic ecosystems. We encourage contributions focusing on carbon in any form (inorganic, organic, dissolved, particulate, gaseous) and which cover spatial scales ranging from catchments to continental scale and beyond.

SS59: Atmospheric Forcing of Marine Microbial Diversity and Activity — See Schedule

Conveners:Markus Weinbauer, Laboratoire d'Océanographie de Villefranche, France, wein@obs-vlfr.fr; Xavier Mari, IRD Montpellier, France, xavier.mari@ird.fr

It is well established that atmospheric depositions of aerosols (such as black carbon) and dust are major local and global climate forcing factors. Also, recent research indicates that atmospheric deposition influences the diversity of microorganisms and microbe-mediated ecosystem functioning in the ocean. However, its influence on the (micro)biota is still poorly studied. This session brings together researchers from different scientific fields such as marine biology and biological oceanography, population and community ecology, diversity research and trophic ecology, and biogeochemistry. The aim is to summarize the research on the effect of atmospheric deposition on the microbiota, compare the effect of various factors such as black carbon and desert dust (and others), evaluate recent developments and potentially come up with a common position paper on global change, atmospheric deposition and the marine microbial life written by interested participants.

SS73: Impact of Submesoscale Processes on Upper Ocean Ecology, Biogeochemistry and Contaminant Dispersal — See Schedule

Conveners:Ken O. Buesseler, Woods Hole Oceanographic Institution, kbuesseler@whoi.edu; Margaret L. Estapa, Woods Hole Oceanographic Institution, mestapa@whoi.edu; David A. Siegel, University of California, Santa Barbara, davey@eri.ucsb.edu

Physical motions associated with submesoscale flows have many important implications for upper ocean planktonic communities and resulting biogeochemical fluxes. For example, upward submesoscale motions can inject nutrients into the euphotic zone, while downward motions can aggregate particles and export them from the euphotic zone. Observations of submesoscale features have largely come from ocean circulation model output or using appropriate satellite data products, and show that submesoscale features are ubiquitous. However, field results linking ocean biogeochemistry to submesoscale flows have lagged numerical experiments. This session brings together studies of submesoscale motions and how they might impact ecological communities, productivity, export and even foraging by higher trophic level species. Such studies may use modeling, remote sensing, sensors on floats, moorings and AUVs, high resolution in-situ sampling and lab experiments to study ocean ecological and biogeochemical processes that are only seen at smaller scales (<10 km). Sites of convergence and divergence that occur on smaller scales will also affect oceanic distributions of plastics, oil spills and other passive tracers, and evidence of these impacts would also be appropriate in this session.