Organiser: IAPSO
Co-sponsor: IACS
Lead Convenor: Isabelle Ansorge (South Africa)
Co-Convenors: Roman Tarakanov (Russia), Karen Heywood (United Kingdom), Steve Rintoul (Australia), Eberhard Fahrbach (Germany)

Scope: The oceanic thermohaline circulation is a vital link in the global transport of heat from the tropics to higher latitudes. The physical structure of this circulation belt and its efficiency in regulating climate is substantially influenced by the nature of water mass exchange between ocean basins. The Southern Ocean plays a critical role in the global ocean circulation, determining the efficiency of its carbon cycle and modulating present-day climate. Dominating the flow of the Southern Ocean is the Antarctic Circumpolar Current (ACC), which, extending unbroken around Antarctica, is the primary means by which heat and salt are transferred between ocean basins. Recent ocean models have indicated that a southern shift and intensification in the prevailing westerly wind field driving the ACC and associated gyres may result in an increase in the upwelling of deep water masses. Such changes could potentially influence the volume and stability of the cryosphere and may have important consequences on the uptake of anthropogenic CO2.
This session will encompass all aspects of the physical sciences of the Southern Ocean.  It provides an opportunity to showcase both observational and modelled results on the linkages between the ocean circulation and biological/biogeochemical processes. Emphasis will be placed on the role, forcing and dynamics of the ACC and the Weddell and Ross gyres in a changing climate; their variability and sensitivity to inter-ocean transport of heat and freshwater anomalies, the role of sea ice formation and its processes, the interaction of the Southern Ocean with the Antarctic ice sheet, exchange of water mass properties and the Southern Ocean’s influence on global carbon and nutrient budgets. Furthermore, this session encourages presentations analyzing the interaction between atmosphere and ocean variability, and in particular fluctuations linked to global scale processes such the Antarctic-ENSO teleconnection and the Southern Annular Mode.

Keywords: Southern Ocean, ice sheet, thermohaline, ocean circulation, carbon cycle, Antactic Circumpolar Current, CO2 uptake, biogeochemical processes, Weddell gyre, Ross gyre, ENSO, Southern Annular Mode

Review: All contributed abstracts will be reviewed by the Convenors

Organiser: IAPSO
Co-sponsor: IACS and IAMAS
Lead Convenor: Bruno Tremblay (Canada)
Co-Convenors: Göran Björk (Sweden), Claude Duguay (Canada), John Turner (United Kingdom), John Cassano (United States of America)

Scope: The Arctic has witnessed large changes in recent years. Of these changes probably the best documented is the decline of its sea ice cover particularly apparent at the end of the summer melt season. Other changes include the river runoff, surface air temperature, sea level pressure, storminess, etc. In the future, GCMs also simulate sharp decline in the sea ice cover leading to a practically ice free Arctic in the late summer and early fall. This new state of the system may lead to drastically different ocean-atmosphere heat and moisture fluxes and associated circulation changes in the atmosphere and ocean. In this session we welcome contributions that address resent observed changes in the Arctic climate system and strive to characterize a possible new state of the atmosphere/ice/ocean system including the potential effect on the biosphere.
Note also "J-C01 Arctic System Modelling"

Keywords: Arctic Ocean, Ice cover, Arctic climate system, decline of sea ice, ice-free Arctic

Review: All contributed abstracts will be reviewed by the Convenors.

This Inter-Association Symposium is a continuation of the Union Symposium U08 having the same title and scope.

Organiser: IAPSO
Co-sponsors: IACS, IAG
Lead Convenors: John Church (Australia), Simon Holgate (United Kingdom)
Co-Convenors: Georg Kaser (Austria), C. K. Shum (United States of America), Philip Woodworth (United Kingdom), Wolfgang Bosch (Germany)

Scope: Global and regional sea-level change has become a high profile scientific issue with great societal importance. Warming oceans, melting glaciers and potentially much larger contributions from the Greenland and Antarctic Ice Sheets are all likely to lead to a substantial rise in sea level during the 21st century and beyond. Sea-level changes across a broad range of time- and space-scales. Understanding both the temporal and spatial variability of sea-level change urgently needs input from a wide range of disciplines, including studies of the atmosphere, ocean, cryosphere (glaciers, ice caps, frozen grounds, and ice sheets), terrestrial water storage and discharge, and the elastic and visco-elastic response of the solid earth to changes in surface loading and Pleistocene deglaciation.

This Symposium aims to bring together the diverse disciplines involved in sea-level research in a way that will provide opportunities for cross-fertilisation of ideas and dissemination of the most up to date results in this rapidly changing field. All contributions to improving understanding of the past and future projections of sea-level change will be considered including satellite observations such as altimetry, GPS, gravity and synthetic aperture radar, in situ instrumental and palaeo observations, theoretical understanding and numerical modelling. The Symposium will focus on: (i) Remotely sensed, in situ and palaeo observations of global and regional sea-level change; (ii) Evidence and understanding of cryospheric change, particularly fast, dynamic ice processes; (iii) Observations and modelling of changes in ocean mass and ocean thermal expansion; (iv) Changes in terrestrial water storage and discharge, including human made dams/reservoirs; (v) Understanding global averaged sea-level change and the regional distribution of sea-level change; and (vi)·Dynamical modelling of sea level variability at global and regional scales, including the prediction of extreme sea levels.
Abstract submissions are encouraged for talks and posters in any of the above areas.

Keywords: sea-level change, warming ocean, melting glacier, Greenland, Antarctic, ice sheet, atmosphere, ocean, cryosphere, observations, modelling, prediction of extreme sea level.

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Eugene Morozov (Russia)
Co-Convenors: Silvia Blanc (Argentina), Peter Chu (United States of America)

Scope: The symposium is planned to discuss the new results of research in physical and chemical oceanography concerning circulation, water masses and their interaction, currents, wind waves, internal waves, tides, and other phenomena in different regions of the ocean. Special sessions are planned to discuss Remote Sensing. Variability of oceanic processes on different space and time scales will be considered. The topics of the symposium include numerical and laboratory modelling, circulation and water masses, chemical distributions and interactions as well as sea ice, variations in sea level and storm surges. The symposium is intended to touch upon all problems of physical and chemical oceanography not included in the themes of other symposia.

Keywords: Physical oceanography, chemical oceanography, circulation, waves, oceanic processes, modelling, sea ice, storm surges, remote sensing,

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Stefania Sparnocchia (Italy)
Co-Convenors: Bo Gustafsson (Sweden), Atsuhiko Isobe (Japan), Sayed Sharaf el Din (Egypt), Kai Wang (P.R. China)

Scope: This symposium will specifically deal with physics and biogeochemistry of marginal, enclosed and semi-enclosed seas.  They often possess complex multi-layered, mesoscale-dominated circulation influenced by variable bottom topography, atmospheric forcing, large evaporation, river runoff, and tides to varying degrees.
They also exhibit highly diverse and multiply-controlled ecosystem structures and biogeochemical cycling. Because of the limited geographical extension and the timescales involved in their processes, they are widely recognized as natural laboratories for studying oceanic processes and interactions between the physical, biogeochemical and climatic spheres.

Keywords: Physical and biochemical processes, marginal seas, semi-enclosed seas, circulation, ecosystem structures

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Trevor J McDougall (Australia)
Co-Convenors: Toshiyuki Hibiya (Japan), Barry Ruddick (Canada), Jennifer MacKinnon (United States of America)

Scope: Ocean mixing processes are important for the ocean circulation as well as for explaining the patterns of temperature, salinity and other tracers that we see in the ocean.  This session covers all aspects of ocean mixing processes from observations, theory and modelling studies, and from surface, interior and near-boundary mixing.  The session encompasses both small-scale diapycnal mixing processes as well as mesoscale mixing processes.  

Keywords: Ocean Mixing, tracers, modelling, diapycnal mixing processes, mesoscale mixing processes

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Andrea Bergamasco (Italy)
Co-Convenors: Anna Wåhlin (Sweden), Matthev England (Australia)

Scope: This symposium will address the "Thermohaline Circulation (THC) and Deep Ocean ventilation",including (but not limited to) the variability of the THC in both Hemispheres, its impact on global climate and the dynamics of deep currents.
We welcome presentations on the following topics: (1) North Atlantic Deep Water stability and variability, (2) Southern Ocean THC and interbasin exchanges, (3) Ocean THC and links to the Carbon Cycle, (4) THC variability from proxy records, (5) Downslope flows and Deep Boundary Currents, (6) Deep ocean ventilation and carbon, (7) Water mass formation processes and their representation in large-scale models.
We encourage presentations analyzing the processes in an Earth System framework, the interactions between the deep ocean and the other components of the Earth System, as well as the linking between the deep physical environment and the global carbon cycle.
Presentations of results derived from field- and experimental studies as well as modelling at all scales are welcomed. This includes research on bottom boundary dynamics, deep ocean flows and the global thermohaline circulation.
The aim is to assess the present state of knowledge in these topics and the future directions required in observations and modelling of the THC.

Keywords: Thermohaline circulation, carbon cycle, downslope flows, deep boundary currents

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: John Middleton (Australia)
Co-Convenors: Katy Hill (Australia), Susan Wijffels (Australia)

Scope: Much effort is being put into developing and maintaining systematic ocean observing systems. Recent advances over the last decade include: the establishment of the Argo array providing profile and velocity data with global coverage down to 2000m depth; and high precision satellite altimetry and ocean colour; moored time-series stations are also being established globally, both coastally and in the deep ocean; sustained glider missions are beginning and HF RADAR systems deployed. The session invites papers on the advances in understanding of oceanic processes (including climate) based on systematic observing systems. Papers are particularly welcome that shed light on the adequacy (or otherwise) of the present observing systems' design and data quality.

Keywords: ocean observing systems, satellite altimetry, HF Radar, ocean processes, climate

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Lisa Beal (United States of America)
Co-Convenors: Shiro Imawaki (Japan), Ming Feng (Australia)

Scope: Western Boundary Currents are important components in the climate system - advecting heat rapidly poleward from the tropical regions - and their extensions produce some of the world’s largest air-sea fluxes. Eastern Boundary Currents are typically associated with the most productive regions of the oceans - about 30% of the world’s fish catch comes from eastern boundary upwelling systems. Hence, changes in boundary current systems related to both natural variability and to anthropogenic climate change stand to have considerable regional effects, such as on rainfall and fish catch, as well as potential feedbacks on the global thermohaline circulation. In the realm of mixing, boundary currents stand out as complex regions of both enhanced and dampened mixing: the proximity of topography, internal wave trapping, and energetic mesoscale instabilities heighten mixing, while strong fronts act to dampen it.
This session offers a chance for a diversity of experts interested in these different boundary regimes over a wide range of timescales, to share perceptions and remaining questions in a single forum. We invite contributions on the surface fluxes, circulation, and mixing associated with Eastern and Western Boundary Current systems, as well as studies of their variability, including future projections under climate change scenarios.

Keywords: Boundary currents, climate change, air-sea fluxes

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IAPSO
Lead Convenor: Denise Smythe-Wright (United Kingdom)
Co-Convenors: David Turner (Sweden), Johan Middleton (Australia)

Scope: Over the last 50 years oceanic pH has decreased by 0.1 units and if current trends continue there will be a reduction of 0.7 units by 2250.  The impact of this change on marine ecosystems, in particular on calcifying organisms such as coccolithophores and on coral reefs, is causing increasing concern.  However, the decrease in pH will also have an impact on the chemical speciation and bioavailability of nutrients and trace metals that are essential for all living organisms. Consequently ocean acidification will have important consequences for marine biota both in the water column and on the sea floor as well as on ocean organic and inorganic carbon fluxes.  It may also influence the atmospheric chemistry of other gases if their release by phytoplankton is altered.
In this session we welcome oral presentations and posters on all aspects of ocean acidification, from seawater carbonate chemistry, through impacts on both marine and atmospheric systems to any technological challenges we face.

Keywords: ocean acidification, coral reef, pH, calcifying organisms, trace metals, carbonate chemistry

Review: All contributed abstracts will be reviewed by the Convenors.

Organiser: IASPEI, IUGG, and Comprehensive Nuclear Test Ban Treaty Organization (CTBTO)
Co-sponsors: IAMAS, IAPSO
Principal Convenors: Ola Dahlman (Sweden), Zhongliang Wu (China)
Co-convenor: Andrew Forbes (United Kingdom), Lassina Zerbo (Burkina Faso), David Jepsen (Australia)

Scope: The global verification system of the Nuclear Test Ban Treaty (CTBT) relies more on cutting-edge science and technology than any other international arms control treaty. All components of the CTBT’s unique verification system – the International Monitoring System (IMS) with a global network of 337 monitoring facilities, the International Data Centre (IDC) for the analysis of large amounts of data, and an On-Site Inspection Regime (OSI) that utilizes a series of high-resolution technologies – are dependent on ongoing development of science and technology and a close relation to, and interaction with, the scientific community. The symposium will be focused on, but not limited to, the scientific topics of the CTBTO verification system (seismological, infrasound, hydro-acoustic and radionuclide monitoring; atmospheric transport modelling; and high-resolution geophysical and radionuclide surveys) and will include an overview of the verification system, its current status, and the underpinning sciences. Because the global verification system uses multiple technologies to detect seismo-acoustic events, which may be nuclear in origin, studies exploiting the synergy between sciences cross-cut the topics of several IUGG Associations. Contributions on the use of CTBT monitoring data to enhance sustainability (such as preparedness for and warning of natural hazards and the management of nuclear incidents) are welcome. New developments in geophysical science and technology and their implications for CTBT monitoring and the use of CTBT monitoring data in basic geophysical studies on the physics and chemistry of the Earth's interior are also issues of interest to this symposium.

The theme of the 2011 IUGG General Assembly is “Science for a Sustainable Planet”. Nuclear disarmament and non-proliferation are essential elements in creating a Sustainable Planet. Science and technology have been important to develop the verification regime of the Comprehensive Nuclear Test Ban Treaty (CTBT), the most extensive international verification system ever created. The purpose of this regime is to detect and locate nuclear explosions in the atmospheric, underwater and underground. The main challenge is to monitor underground tests and discriminate such tests from other artificial and/or natural events, in particular earthquakes.

The verification system is built on a number of sciences such as seismology, infrasound, hydro-acoustics, and radionuclide observations. Modelling and monitoring of atmospheric transportation play an important role in the tracing of radionuclides, which is crucial in identifying a nuclear test. To provide high quality data, observation systems have to be operated and maintained in a professional way, and their performance have to be monitored and evaluated. The application of new concepts, such as data fusion and data mining, are essential to analyse and to exploit a rapidly increasing amount of data. The International Monitoring System (IMS) and similar large scale observation systems established for scientific purposes are, in a way similar to accelerators in high-energy physics and satellites in space science, “big science device” providing not only experiences and lessons on monitoring practice, but also unique datasets of great value in basic research and in the application of science and technology for sustainability. New frontiers in modern geophysics, such as high-precision seismology, high-performance computation for atmosphere transport modelling, automatic processing of signals, and satellite remote sensing technology, as well as the newly developed “Digital Earth” technique, have provided the monitoring of CTBT with new opportunities and new challenges. Remarked by a series of important events, especially the Conference “CTBT 1996-2006: Synergies with Science and Beyond”, and the 2009 Conference “International Scientific Studies” (ISS09), a new era of cooperation between CTBT monitoring communities and scientific communities has started, which will contribute both to the CTBT monitoring practice and to the development of geophysical science.

To reflect the up-to-date advancements in this inter-disciplinary field, this Union symposium is focused on, but not limited to, geophysical studies of CTBT monitoring. Contributions from seismic, hydro-acoustic, infrasound, and radionuclide monitoring, data processing, data fusion and data mining, and system performance evaluation are welcome to the session, highlighting the implementation and synergy of different technologies for CTBT monitoring. Contributions on the use of CTBT monitoring data to enhance sustainability (such as the preparedness of natural hazards and the management of nuclear incidents) are also welcome. New developments of geophysical science and technology and its implication for CTBT monitoring and the using of CTBT monitoring data in basic geophysical studies on the physics and chemistry of the Earth’s interior are also issues of interest to this Union symposium. All contributions to the symposium are in the form of posters. Oral presentations are by invitation only.

Keywords: seismology, infrasound monitoring, hydro-acoustic monitoring, radio nuclide monitoring, atmospheric transport modelling, data mining, data analysis, sustainability.

Review: All contributed abstracts will be reviewed by the convenors.

Options: All contributed abstracts will be presented as posters. Only invited papers will be scheduled for oral presentations.

Organiser: IUGG Union Commission for Data and Information
Co-sponsors: ICSU, IAGA, IAPSO
Principal Convenors: Peter Fox (United States of America), Charles Barton (Australia)
Co-Convenors: Alik Ismail-Zadeh (Germany), Weijia Kuang, Ruth Neilan, Mark Parsons (all United States of America), Roger Proctor (Australia), Bernd Richter (Germany), Adelina Geyer Traver (Spain), Richard Swinbank (United Kingdom).

Scope: Science has fully entered a new mode of operation. Data science (including e-science) defined as a combination of science, informatics, computer science, cyber infrastructure and information technology is changing the way all of these disciplines do both their individual and collaborative work. IUGG scientists are facing global problems of a magnitude, complexity and interdisciplinary nature that progress is limited by available knowledge and skills that are required to solve these problems. At the heart of this new way of doing science, especially experimental and observational science but also increasingly computational science, is the generation of data. As a result, new opportunities exist for the assimilation of data into a variety of geophysical models that span several geoscience disciplines. The goal of this session is to assess the current state of data science and informatics effort in support of IUGG science and indicate successful progress made to date and the challenges that presently exist. The session will also highlight the progress and perspectives in data assimilation studies in various fields of geophysics.

Keywords: informatics, computer science, cyber infrastructure, information technology, data generation.

Review: All contributed abstracts will be reviewed by the convenors

Options: All contributed abstracts will be presented as posters. Only invited papers will be scheduled for oral presentations.

Organiser: IAMAS
Co-sponsors: IAHS, IAPSO, IASPEI
Principal Convenors: Michael MacCracken (United States of America), Alan Robock (United States of America)
Co-convenors: Larry Brown (United States of America), Ken Denman (Canada), Dave Jackson (United States of America), Dongxiao Zhang (China)

Scope: With the pace of climate change increasing and the array and magnitude of climate impacts intensifying, increasing attention is being paid to the potential for limiting the effects of anthropogenic climate change through large-scale geotechnical means, often called geoengineering. The most discussed approaches include deliberately altering the Earth's radiation balance and intervening in the carbon cycle or other biogeochemical cycles, for example via scrubbing carbon dioxide from the atmosphere. Although specific approaches have been proposed, relatively little is known about their potential effectiveness and possible unintended consequences. Issues of technological feasibility are also largely unexplored. The set of invited presentations will describe and address the potential effectiveness and scientific and technical problems associated with deliberate climate modification, including the potential for enhancement of terrestrial and oceanic carbon sinks. Presentations will cover modeling studies of the climatic impacts of proposed schemes for altering the absorption of solar radiation; studies of unintended environmental consequences; and evaluations of technological feasibility. Recognizing that geoengineering raises a range of environmental, societal, and governance issues, perspectives on how these complexities interface with proceeding with scientific research and potential deployment will also be offered.
This symposium is continued in greater depth in the Joint Symposium J-M01/J-V06 “Geoengineering: Can it limit climate change and its impacts?”

Keywords: geoengineering, climate intervention, global warming, carbon sequestration, solar
radiation management

Options: All papers in this symposium will be invited. Please contribute abstracts to the related Joint Symposium J-M01/J-V06 “Geoengineering: Can it limit climate change and its impacts?” which will have both oral and poster presentations.

Organisers: IAGA and IUGG Commission on Mathematical Geophysics
Co-sponsors: IAG, IAPSO
Principal Convenor: Matthias Holschneider (Germany)
Co-convenors: Shin-Chan Han (United States of America), Nico Sneeuw (Germany), Gordon Swaters (Canada)

Scope: Advances in mathematics have always been in close relation with progress in the natural sciences and vice versa new mathematical tools have pushed forward the frontiers of knowledge. This symposium mission is to exploit breakthroughs in the mathematical approaches to various fields of geophysics. In particular new developments in functional and numerical analysis and in statistics shall be presented with their implication for geophysical data analysis and system modelling. We invite contributions from new approaches using innovative field parameterisations of potential fields like space and time localizing functions to the analysis and processing of irregular data geometries like satellite observations of magnetic or gravity fields. Kalman filtering techniques and data assimilation have opened new perspectives in time dependent geopotential field modelling. New developments in numerical techniques make it possible to simulate the dynamical behaviour of geophysical systems on geologic timescales (mantle processes) and very short timescale (core processes) many different space and time scales. The recently exploding field of Bayesian analysis and machine learning allows innovative ways of exploring data with high uncertainty as in the field of seismic risk estimation. An important topic to be addressed in this symposium is also the connection of models and data. In particular new approaches to model validation and model selection are welcome.

Keywords: geopotential fields, processing irregular data geometry, magnetic field, gravity field, seismic risk, Kalman filtering, data assimilation, analytical and numerical techniques, Bayesian analysis, model validation

Review: All contributed abstracts will be reviewed by the convenors.

Options: All contributed abstracts will be presented as posters. Only invited papers will be scheduled for oral presentations.

Organiser: IAPSO
Co-sponsors: IACS, IAG
Lead Convenors: John Church (Australia), Simon Holgate (United Kingdom)
Co-convenors: Georg Kaser (Austria), C. K. Shum (United States of America), Philip Woodworth (United Kingdom)

Scope: Global and regional sea-level change has become a high profile scientific issue with great societal importance. Warming oceans, melting glaciers and potentially much larger contributions from the Greenland and Antarctic Ice Sheets are all likely to lead to a substantial rise in sea level during the 21st century and beyond. Sea level changes across a broad range of time- and space-scales. Understanding both the temporal and spatial variability of sea-level change urgently needs input from a wide range of disciplines, including studies of the atmosphere, ocean, cryosphere (glaciers, ice caps, frozen grounds, and ice sheets), terrestrial water storage and discharge, and the elastic and visco-elastic response of the solid earth to changes in surface loading and Pleistocene deglaciation.

This Symposium aims to bring together the diverse disciplines involved in sea-level research in a way that will provide opportunities for cross-fertilisation of ideas and dissemination of the most up to date results in this rapidly changing field. This Symposium will consider all contributions to improving understanding of the past and future projections of sea-level change. This includes satellite observations such as altimetry, GPS, gravity and synthetic aperture radar, in situ instrumental and palaeo observations, theoretical understanding and numerical modelling. The Symposium will focus on: (i)· Remotely sensed, in situ and palaeo observations of global and regional sealevel change; (ii) ·Evidence and understanding of cryospheric change, particularly fast, dynamic ice processes; (iii) Observations and modelling of changes in ocean mass and ocean thermal expansion; (iv) Changes in terrestrial water storage and discharge, including human-made dams/reservoirs; (v) Understanding global averaged sea-level change and the regional distribution of sea-level change; and (vi)·Dynamical modelling of sea level variability at global and regional scales, including the prediction of extreme sea levels. This symposium will continue as the IAPSO-lead Joint Symposium JP3.

Keywords: sea-level change, warming ocean, melting glacier, Greenland, Antarctic, ice sheet, atmosphere, ocean, cryosphere, observations, modelling, prediction of extreme sea level.

Review: All contributed abstracts will be reviewed by the convenors.

Options: Only invited papers will be scheduled for oral presentations within the union symposia. All other accepted abstracts will either be presented as posters or, if the author prefer, moved as oral to the IAPSO-lead Joint Symposium JP3.

Organiser: IAHS
Co-sponsors: IACS, IAG, IAMAS, IAPSO
Principal Convenor: Pierre Hubert (France)
Co-convenors: Andrea Flossman (France), Manfred Lange (Cyprus), John Pomeroy (Canada), Paul Tregoning (Australia), Susan Wijffels (Australia)

Scope: Based on the observation of the continuous movement of water, the idea of a hydrological cycle appeared in the most remote antiquity, but the corresponding scientific concept was coined only three centuries below by Pierre Perrault and Edmund Halley, based on their measurements and water balance computations. Today the hydrological cycle is well known and taught as soon as in primary schools. But do we really understand this extraordinarily complex system, which operates over huge time and space scales, involves the flow of liquid, solid and vapour phases of water and whose processes shape the face of the Earth by impacting biology, geochemistry, geophysics, climatology and redistributing matter and energy? We still have a lot to learn about the hydrological cycle. To take only a few examples: what is the uncertainty regarding the Earth’s water inventory, water phase and fluxes?  Do we really know what a cloud is and how it behaves?  Can we predict streamflow from physical first principles? Do we really know the paths of water on the continents, between precipitation and the continental reservoirs of surface, ground, snow and glacier water and the oceans? This symposium will be devoted to these gaps which jeopardize many scientific and practical activities such as water resources prediction and assessment and to the ways to overcome them. All contributions from geoscientists developed in an interdisciplinary spirit will be welcome.

Keywords: Hydrological cycle, water cycle, hydrosphere, atmosphere, cryosphere.

Review: All contributed abstracts will be reviewed by the convenors.

Options: All contributed abstracts will be presented as posters. Only invited papers will be scheduled for oral presentations.

Organiser: IAGA – as part of IUGG Geoscience in Africa initiative and the eGY-Africa program.
Co-sponsors. IAG, IAHS, IAMAS, IAPSO, IASPEI, IAVCEI, African Geospace Society (AGS), Association of African Universities (AAU), Africa Earth Observing Network (AEON), AfricaArray; ICSU Regional Office for Africa, CODATA, International Network for the Availability of Scientific Publications (INASP), UN Global Alliance for Information and Communication Technologies and Development (UN-GAID), U.S. InterAcademy Panel on International Issues (IAP); European Enabling Grid for e-Science (EGEE); Geoscience Information in Africa (GIRAF); and the Abdus Salam International Centre for Theoretical Physics in Trieste (ICTP).
Principal Convenor: Charles Barton (Australia)
Co-convenors: Abdelkrim Aoudia (Algeria), Hussein A. Abd-Elmotaal (Egypt), Rabiu Babatunde (Nigeria), Harouna Karambiri (Burkina Faso), Christine Amory-Mazaudier (France), Laban Ogallo (Kenya), Bamol Sow (Senegal), Maarten de Wit (South Africa).

Scope: The session will cover a combination of both the leading Earth and space science being undertaken and planned in Africa in the areas covered by all eight Associations, and also infrastructure issues (such as efforts to create a better professional environment for African scientists, open access to publications, internet connectivity, support for African science, education, and training). The symposium will provide (i) a forum for presenting and discussing the latest African geoscientific research, (ii) a cross-disciplinary view of geoscientific activity in Africa (Africa being the focus of the symposium), (iii) a stimulus for stronger interest and participation in African science by African and non-African scientists, and (iv) an opportunity to explore progress in creating a better professional working environment for people engaged in scientific research, education, and training in Africa.

Keywords: geoscience in Africa, integrated African research, unique African geoscience, research and education infrastructure, Internet connectivity, research and education networks, open access to publications, professional geoscientific bodies.

Review: All contributed abstracts will be reviewed by the convenors.

Options: All contributed abstracts may be presented as posters. The convenors will invite selected papers for oral presentations.

Organiser: IUGG
Co-sponsors: IACS, IAG, IAGA, IAHS, IAMAS, IAPSO, IASPEI, and IAVCEI
Principal Convenors: Harsh Gupta (India) and László Szarka (Hungary)

Scope: With the passage of time, the importance of "Geophysics" as a discipline is increasing. A large number of young persons are joining the Geophysics stream. IUGG is conscious of the aspirations of young geophysicists. This Union Symposium would have speakers, preferably 35 years old or younger, from the 8 Associations of IUGG and a few other invited young persons to share their experience, expectations, successes and concerns in development of Geophysics.

This symposium is under active development.

Organiser: IACS
Co-sponsors: IAMAS, IAPSO
Lead Convenors: Scott Elliot (United States of America), Andrew Roberts (United States of America)
Co-Convenors: Ralf Döscher (Sweden), Annette Rinke (Germany)

Scope:  This session will focus on model development and results that seek to explain physical-biogeochemical-ecological-human interconnectivity within the arctic environment.  Model developments and results presented at this session will typically relate to the use or evaluation of coupled regional arctic sea ice-ocean-atmosphere climate models with coupled 'system' components, such as sophisticated biogeochemistry, hydrology, marine and terrestrial ecosystems, atmospheric chemistry and aerosols, ice-sheets and human-system components.

Keywords: Arctic, regional models, ice-ocean-atmosphere climate models, earth system modelling

Review: All contributed abstracts will be reviewed by the Convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.
Please note also 'J-P02 Future State of the Arctic and Potential Impact"

Organiser: IACS
Co-sponsors: IAPSO
Lead Convenors: Roland Warner (Australia), Mike Dinniman (United States of America)
Co-Convenors: Andrew Mackintosh (New Zealand) Lars Smedsrud (Norway), Anna Wåhlin (Sweden)

Scope: Floating glacial ice, in ice shelves and glacier tongues, forms an important linkage between polar ice sheets and the ocean. Thermal interaction with subglacial ocean circulation couples ice shelves and glacier tongues to the global climate system, making this part of the ice sheet margin sensitive to climate change. The rapid disintegration of several Antarctic ice shelves over recent decades has been attributed to combinations of atmospheric and oceanic influences, internal ice shelf dynamics and fracture and rift development. Much of the continental ice is discharged through these regimes and the balance of forces within ice shelves imposes boundary conditions on flow in ice streams and outlet glaciers. Uncertainty about these evolving boundary conditions at the ice margin on interior flow leads to uncertainty about contributions to future sea-level. Contributions are sought addressing all aspects of ice shelves and glacier tongues and their interaction with the climate system, including observations and modelling of: the structure, dynamics and evolution of ice shelves; their linkages with the broader climate system; sub-shelf ocean circulation and ice shelf-ocean interactions; rifting and iceberg calving, and the influence of changing ice shelves on grounding lines and ice stream dynamics. In particular, overviews of the current state of knowledge are welcomed.

Keywords: floating ice, ice shelves, glacier tongues, ice shelf-ocean interaction, grounding line, ice streams, rifting, calving, icebergs, basal melting, basal freezing, frazil ice, marine ice, ice dynamics, modelling, climate change.

Review: All contributed abstracts will be reviewed by the Convenors.

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers: IAHS (ICGW, ICWQ), IAPSO
Lead Convenor: Makoto Taniguchi (Japan)
Co-Convenors: Thomas Stieglitz (Australia), Donald Rosenberry (United States of America), Kate Heal (United Kingdom), Jean-Francois Exbrayat (Germany), Bo Gustafsson (Sweden)

Scope: This session deals with the interaction between the surface water/groundwater and ecosystems in the coastal zone.  Fresh water (including groundwater and river water) dependent ecosystems (FDE) frequently occur in wetlands, terrestrial vegetation, riparian areas, coastal zones, coral reefs and cave ecosystems.  Critical damages or more gradual changes in composition and/or ecological function of communities are expected in these areas according to climate change and/or human impacts on hydrological settings.  On the other hand, the degradation of vegetation can conversely cause a shift of the related hydrological environment including water quality and water mass balance. The approaches for quantifying hydrodynamics in watersheds and submarine groundwater discharge in coastal areas are now becoming better established. Thus, it appears to be time to integrate such interactions between ecosystems and river water/groundwater systems.  This session provide contributions to the broad examples collected in a variety of fresh water dependent ecosystems in the coastal zone, including field observations and model predictions.

Organisers: IAMAS (ICDM, ICMA), IAPSO, IAHS, IAGA, IACS
Lead Convenor: William Lahoz (Norway)
Co-convenors: Craig Bishop (United States of America), Mu Mu (China), Michele Rienecker (United States of America), Jeffrey Walker (Australia), Tomoko Matsuo (United States of America), Ian Fenty (United States of America)
           
Scope: The session will provide a forum for presentation and discussion of the latest research in data assimilation and ensemble forecasting. The effectiveness of data assimilation and ensemble forecasting is inextricably linked to our ability to estimate the distribution of truth given limited information. Given imperfect and sparse observations together with an imperfect forecasting system, data assimilation focuses on estimating the distribution of current and past states while ensemble forecasting strives for the distribution of future states. Data assimilation schemes need an estimate of the distribution of truth given a short term forecast – a key objective of ensemble forecasting. The intertwining of the aims of data assimilation and ensemble forecasting makes it likely that data assimilation experts can help ensemble forecasting experts and vice-versa. We are calling for presentations of outstanding research in data assimilation and ensemble forecasting. Particular data assimilation topics include:

• Advanced assimilation methods, including hybrid variational and ensemble-based approaches, weak constraint 4D-VAR and model error estimation;
• Improved use of observations: observing system experiments and observing system simulation experiments, adaptive observing methods, calculation of observation sensitivities;
• Assimilation of data from new satellite instruments, such as COSMIC, CloudSat, IASI, SMOS, Aquarius and ADM-Aeolus;
• Space Weather, including applications to the heliosphere, the magnetosphere, and the ionosphere-thermosphere system;
• Polar assimilation: exploiting the considerable data collected during the IPY and subsequently via the Arctic Observing Network.

Contributions on ensemble forecasting for short, medium, seasonal and climate time scales are all welcome. Specific sub-topics include:

• improved methods for initializing ensemble forecasts,
• estimation and representation of model error, and
• ensemble post-processing to optimize the value of probabilistic forecasts to decision makers.

Keywords:  observations, satellite data, advanced methods, decision makers

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers:  IAMAS (ICCL), IAPSO
Lead Convenor: Richard Bouchard (United States of America)
Co-convenors:  Keith Alverson (France), Thierry Fichetet (Belgium)

Scope: This symposium takes it cue from the wide-spread, global efforts to advance the understanding of climate issues, such as climate change, climate variability, and climate adaptation by observing the world around us, as evidenced by the densification and advancement of a variety of direct and proxy observations provided by mixture of in situ and remotely-sensed observing systems.  Recent years have seen those efforts culminate with nearly world-wide participation in the Global Earth Observing System of Systems (GEOSS), the maturation of individual regional observing systems, the fielding of new satellite and observing systems, and advances in observations of and which span the air-sea, sea-ice, land-sea, and atmospheric structure boundaries. However, many of these advances and the sustainability of observing systems themselves may have been impacted by the changing state of the global economy since the heady days of IUGG XXIV in 2007.

While the observations themselves provide valuable insights on climate issues by trend analysis, the validation of model hindcast, and short-term model prediction, the application of the observations can serve greater utility by their proper and rigorous integration through time-tested or novel data assimilation schemes.

Sample topic areas include assimilating disparate and perhaps conflicting observations into climate analysis and modelling; the application of earth observations in support of climate adaptation strategies; climate monitoring; status and plans of existing and planned observing systems; observation and assimilation of stable water isotopes; techniques and parameters that provide continuity and target fluxes across interfaces, such as the land-sea interface, sea-ice interface,  the tropopause, the stratopause, and the mesopause; effects of the global economic change on sustaining established and planned climate observing systems; and, the role of climate principles in fielding new technologies for the sustainability of observing systems.

Keywords: Global observation systems, GEOSS, climate modelling

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers:  IAMAS (ICMA, ICDM, ICCL), IAPSO
Lead Convenor: Elisa Manzini  (Italy)
Co-convenors: Joan Alexander (United States of America), Greg Roff (Australia)

Scope: Stratospheric variability and change are now recognized to have an active role in troposphere-stratosphere dynamical coupling. In investigating climate and its variations, it is therefore of interest to address the full stratosphere-troposphere-ocean system.

The aim of this symposium is to invite contributions from theoretical, observational and modeling studies on the interactions between the stratosphere, the troposphere and the ocean. Topics of particular interest include but are not limited to

• mechanisms of the two-way dynamical coupling among the layers and their relevance for weather to climate time scales
• importance of the interaction with the ocean to understand the role of the stratosphere in climate
• predictability of the stratosphere-troposphere-ocean system at seasonal and decadal time scales
• stratospheric change and the role of ozone recovery in climate with coupled atmosphere-ocean models with a well-resolved stratosphere
• coupling within the tropical stratosphere-troposphere ocean system, with emphasis on understanding tropical variability and interactions across different time and spacial scales

Keywords: Air-sea interaction, down-ward control, ozone recovery

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organsiers:  IAMAS (ICPM), IAPSO, IACS
Lead Convenor: Siobhan O’Farrell (Australia)
Co-convenors: Jason Box (United States of America), David Reusch (United States of America), Michael Town (France)

Scope: This last decade has seen record sea ice-extent minima in the Arctic while the Antarctic has shown no change in sea ice extent.  At the same time, the Greenland ice sheet, Antarctic Peninsula ice shelves and West Antarctic outlet glaciers and surface temperatures all exhibit increasing evidence of change. The combined effects of anthropogenic forcing and natural variability modes are thus yielding different responses in the atmospheric, oceanic, and cryospheric components of the two polar climate systems.
This session will investigate the contrasting climate responses in atmosphere, ocean and cryosphere, through several key questions:
(1) Where can we detect the anthropogenic signal in the polar climate system (e.g., temperature, sea level pressure, sea ice extent, ocean currents, ocean water mass properties, etc.)? 
(2) Can we identify how the large-scale natural variability also driving the climate system affects these same climate variables, whether the changes exceed natural variability “noise” levels in the system, and does reality mirror model-projected change?

We solicit papers from the atmospheric, oceanic and cryospheric communities, from observational, theoretical and modelling perspectives, addressing these questions and the role of natural variability and/or anthropogenic signals in individual climate components, or across the climate system.

Keywords:  climate response, climate detection, cryosphere, modes of variability, climate variables, ocean water mass changes.

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers: IAMAS (ICCL, ICDM), IAPSO , IACS
Lead Convenor: Natalia Andronova (United States of America)
Co-convenors: Neil Holbrook (Australia), John Nielsen-Gammon (United States of America), Adam Scaife (United Kingdom), Toshio Yamagata (Japan), Petra Heil (Australia)

Scope: Effective adaptation to climate change requires specific probabilistic forecasts of the future state of global and regional climate years to decades in advance.  While much can be learned from studies of the predictability of weather, the future state of the climate system involves the coupled evolution of the atmosphere, oceans, surface water, ice sheets and glaciers, and society (emissions and land use), all of which have widely varying levels of observability and model fidelity, and the entire system is further subject to time-varying external solar and volcanic forcing.  Sensitivity of the climate system to external forcing greatly depends on a wide variety of feedbacks that govern interactions within the climate system. Quantifying the climate feedbacks operating on different spatial and temporal scales has been a great challenge for the climate community, making it difficult to provide clear and adequate scientific information to policymakers. The different temporal and spatial scales of interactions within the whole climate system bring great uncertainties into the analysis of climate sensitivity and feedbacks.  This translates into uncertainties of climate prediction, particularly on regional scales, and requires a close conversation between climate modelers, observatories and stakeholders.

Papers are invited on all aspects of climate sensitivity, predictability and feedbacks from annual to centennial time scales, including: the predictability and sensitivity to initial conditions of individual components of the climate system; nonlinear interactions among components and their effects on predictability; the nature of observations which have or would have the greatest impact on climate predictability; the extent to which climate predictability is sensitive to societal responses to climate change; the spatial and temporal scale dependence of climate predictability; the importance (and probabilistic specification) of time-varying external forcing; and the proper framing of probabilistic climate forecasts to meet societal needs.

Keywords: Probablilistic forecasts, feedbacks, time scales

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers: IAMAS (ICCL,ICDM), IAPSO, IACS, IAHS,GEWEX, CLIVAR
Lead Convenors: Jianping Li (China), John McBride (Australia)
Co-convenors: Bin Wang (United States of America), Jun Matsumoto (Japan), Harry Hendon (Australia), E. Hugo Berbery (United States of America), Richard Grotjahn (United States of America), Michael Montgomery (United States of America), Roger K. Smith (Germany), Masato Sugi (Japan), Georg Kaser (Austria), David S. Nolan (United States of America)
                       
Scope: This is a wide-ranging symposium covering many aspects of tropical weather and climate, but focusing primarily on monsoons and tropical cyclones, which affect the lives of billions of people. It is of great importance to understand the dynamics of monsoons and tropical cyclones, to predict them and project future changes in their nature associated with global warming. This symposium invites contributions regarding observational, diagnostic, theoretical and modeling studies of the nature, variability and mechanisms of monsoons, tropical cyclones and other tropical phenomena.  Presentations about the impact of climate change on tropical circulations are particularly welcome.

The symposium will be focused on the following themes:

• Theme 1.  Monsoon nature and mechanisms of monsoon variability. Monsoons are fundamental regulators of the earth’s energy budget and water cycle, impacting people across Southern Asia and other tropical and subtropical regions around the globe.  This part of the symposium focuses on the nature and mechanisms of monsoon variability at intraseasonal, interannual to millennial timescales; linkages between monsoon and the principal modes of climate variability; air-sea-land interaction within the global monsoon system; monsoon simulation, predictability, prediction and projection. Presentations are also invited on the latest results from monsoon experiments such as the AMY, SCSMEX, MAHASRI, GAME, NAME, MESA and AMMA, etc.
• Theme 2. Tropical cyclones. Tropical cyclones are the most destructive weather systems on the planet. We do not yet fully understand the processes that determine their development and movement to the extent that their properties can be forecasted with precision over a time scale of several days. Research papers are solicited on all aspects of tropical cyclones, especially those concerned with the fundamental dynamical and thermodynamical processes involved as well as the genesis, intensification, movement, and impacts.
• Theme 3.  Tropical circulations. This part of the symposium concerns the diverse range of tropical circulations, including equatorial waves, organized tropical convection, and tropical intraseasonal and inter-annual variability. The symposium will cover the Madden-Julian Oscillation, El Nino Southern Oscillation, the Walker and Hadley Circulations, and their interaction with monsoons and tropical cyclones.  Contributions on the diverse linkages between the tropics, subtropics and midlatitudes are also invited.  We seek to advance and connect understanding in these areas by bringing together diagnostic, theoretical, idealised and realistic simulation, prediction and model intercomparison approaches.

Keywords:Monsoon, Tropical cyclones, tropical circulations, ENSO

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organisers:  IAMAS (ICCL), IAPSO, IACS
Lead Convenor: Michael MacCracken (United States of America)
Co-convenors:  Valérie Masson-Delmotte (France), Alan Robock (United States of America)

Scope: Earth system history makes clear that the climate can span a wide range of states, from widespread glaciation to global warmth with very little ice at all, essentially from what might be called to being dominated by the world’s ice to dominated by the atmosphere’s greenhouse gas concentrations. This symposium, which will have a number of components, is intended to span the spectrum, inviting papers on periods from when the climate was very cold to when it has been hot and including the warming Earth that human activities are now inducing. Papers relating to model development and verification, including determining climate sensitivity, should be submitted to J-M08. Papers relating to the nature of cold to hot climates, transitions from one state to the other, and particularly the transition from the Holocene to the present and into the future should be submitted to this Symposium. Studies and analyses based on observational records (e.g., ice core records) and modelling are both invited, and especially studies that draw from both. The causes of both stability and change are of interest, including the ranges of natural variability and the coupling of changes in climate to the weather, oscillations, and extremes that result.

The components of the Symposium are envisioned to be:

• Pre-Pleistocene warm and cold climates—Insights into the long-term functioning of the climate system
• Glacial cycling during the Pleistocene—A period of large climate swings and feedbacks;
• The Holocene: Its stability and variations—and their causes; and
• The Industrial Era and beyond, covering the response of the climate system to human activities (including particularly reports on model simulations being done for IPCC’s AR5 report)

Keywords: Geological time scales, climate variations, proxy data

Review: All contributed abstracts will be reviewed by the convenors

Options: Accepted abstracts will be presented as either oral or posters as determined by the convenors.

Organiser: IASPEI
Co-Sponsors: IAPSO and IAVCEI
Lead Convenor: Kenji Satake (Japan)
Co-convenors: Vassily Titov (United States of America), Alexander Rabinovich (Russia)

Scope: During 5 years after the catastrophic 2004 Indian Ocean tragedy, the science of tsunami, tsunami warning and mitigation measures have been advancing in unprecedented scale. The Indian  Ocean tsunami demonstrated the catastrophic potential of tsunamis in the absence of hazard and vulnerability assessments, mitigation, and warning systems. In six years after the Indian Ocean tsunami, the tsunami science and many tsunami-related programs have seen dramatic improvements, including observing systems, education and outreach tools, community resilience assessment tools, hazard and vulnerability assessments, modeling, and warning operations. This session provides a forum to discuss successes that have been achieved in the last six years and to identify areas where more studies and improvements are of urgent need.

Organiser: IASPEI
Co-Sponsors: IAPSO and IAGA; An ION Proposal
Lead Convenors:  M. Best (Canada), P. Favali (Italy), Y. Kaneda (Japan), P. Grenard (Austria), R. Stephen (United States of America), P. Tarits (France)

Scope: Coastal, regional and global permanent cabled seafloor observatories are under development and installation in many countries.  These systems have the goal of providing continuous, real-time data from the seafloor and up through the water column for durations longer than five years.  At the same time, the duration of traditional temporary, autonomously recording, seafloor geophysical experiments is being extended to a year or more, resulting in quasi-permanent observational systems. This session will focus on the scientific results from permanent and quasi-permanent seafloor observatories