Full Proposals for IPY 2007-2008 Activities

Proposed IPY Activity Details

1.0 PROPOSER INFORMATION

(Activity ID No: 81)

1.1 Title of Activity
Collaborative Research into Antarctic Calving and ICeberg Evolution

1.2 Short Form Title of Proposed Activity
CRAC-ICE

1.3 Activity Leader Details
Hartmut Hellmer
Alfred Wegener Institute for Polar and Marine Research (AWI)
Germany

1.4 Lead International Organisation(s) (if applicable)
NULL
NULL
NULL
NULL

1.5 Other Countries involved in the activity
Australia
Brasil
France
United Kingdom
U. S. A.
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL

1.6 Expression of Intent ID #'s brought together in this proposed activity
21, 249

1.7 Location of Field Activities
Antarctic

1.8 Which IPY themes are addressed
1. Current state of the environment
2. Change in the polar regions
3. Polar-global linkages/tele-connections
4. Exploring new frontiers
5. The polar regions as vantage points

1.9 What is the main IPY target addressed by this activity
1. Natural or social science

top of page

2.0 SUMMARY OF THE ACTIVITY

CRAC-ICE will be a coordinated investigation into calving processes on three major Antarctic ice shelves, and a (long-term) monitoring of icebergs in the Southern Ocean, including the study of the physical processes related to iceberg drift and decay. The processes leading to a calving event include the initiation and propagation of through-cutting rifts. Iceberg calving can result in a significant loss of mass from the Antarctic ice sheet, and represents ~ 65% of the total ice sheet ablation. Therefore, it is critical to understand the processes which precede and lead up to a major calving event in order to realistically assess how future climate changes might affect the Antarctic Ice Sheet. Post-calving, iceberg drift is influenced by the shape of the coastline, bottom topography, and a combination of tides, currents, wind, and sea ice. Monitoring the evolution of icebergs as they drift into warmer waters provides a valuable experiment in how rapid climate change influences ice shelves – especially such components as firn compaction, the impact of surface meltwater, ponding, and iceberg break-up. Grounded icebergs cause a severe devastation of the sea floor, forcing benthic communities to re-colonise. Iceberg melting and decay represents a significant source of freshwater (and mineral dust) primarily into the upper layers of the Southern Ocean's northern fringe. A stabilisation of the weakly stratified water column has important and poorly understood consequences for sea ice and water masses involved in deep and bottom water formation, and the biology of the euphotic zone.
CRAC-ICE’s first objective is to develop an understanding of the mechanics of ice shelf rift initiation and propagation via three complementary components:1.Fieldwork: Networks of autonomous observation stations (GPS, seismometers, webcams and AWS) will be deployed around selected rift tips on each ice shelf for one year. The measurements will be combined with oceanographic measurements of currents, temperature and salinity, and significant wave heights. These mirror campaigns will provide a continuous time series of rift widening (GPS) as well as rupture locations and source mechanisms (seismic), which can be compared with environmental effects such as large storms. Ground penetrating radar profiles will be collected, to probe the subsurface structure of the rift. Cores will be taken of the mélange inside each rift to determine its composition. On the Ross Ice Shelf, autonomous vertical profilers will be installed beneath a rift to monitor ocean currents and mixing, and to take depth profiles of salinity and temperature on a daily basis for one year.
2.Satellite data analysis: Satellite images (e.g. MODIS, MISR, ASTER, RADARSAT) provide “snapshot” observations of the surface expression of the rift at discrete time intervals. Image pairs provide estimates of velocity, ice strain rates, and rift widening rates on much larger spatial and temporal scales than the ground-based measurements. InSAR analysis using Radarsat will provide rift deformation rates. ICESat/CryoSat laser and radar altimeter data will be used to provide surface profile information for each rift and estimate mélange thickness.
3.Modeling: Physical modelling, using a large ice tank, will be used to simulate ice shelf behaviour over a range of conditions. The results from these experiments, along with data collected in (1) and (2), will be used to construct realistic suites of numerical models of ice shelves which explicitly include fracture physics. This will enable careful hypothesis testing of the mechanisms and processes which occur during ice shelf break up - including the effect of mélange within rifts.
CRAC-ICE’s second objective is the monitoring of iceberg evolution as they drift away from their calving sites, based on:
1.Shipbased observations near drifting bergs, including the deployment of autonomous observation stations on icebergs of various sizes equipped with sensors for position, air pressure, strain and tilt, reporting via the ARGOS system.
2.Satellite data analysis using imagery (e.g. Envisat, Radarsat, ALOS) with different spatial resolution. A pattern-recognition algorithm will be applied to identify and track icebergs with minimum lengths between 200 – 500 m (depending on pixel size). Radar imagery will be used to monitor the physical changes in icebergs (surface melting, firn compaction, ponding, etc.)from their sites of calving through to their final break-up. Estimates of the total mass loss (and related freshwater flux) will be made by combining size information from satellite imagery with freeboard elevation from satellite altimetry (ICESat, CryoSat, Envisat), both compared with modeled melt rates. 3.Modeling of iceberg drift to guide image acquisition. The simulated track will be used to bridge the interval between a pair of images. Modeled side wall (including wave erosion) and basal melting will be used to verify the observed mass losses due to size and freeboard reductions.

2.1 What is the evidence of inter-disciplinarity in this activity?
CRAC-ICE brings together scientists from different disciplines (glaciology, geophysics, oceanography, remote sensing, and biology) working from hemispheric to micro-scales to study the vital problems of iceberg calving, iceberg evolution, and the impact of icebergs on the Southern Ocean environment.

2.2 What will be the significant advances/developments from this activity? What will be the major deliverables? What are the outputs for your peers?
This project will achieve significant advances to all IPY themes except for No. 6.
1: Present environmental status of the polar regions - CRAC-ICE will provide insight into the stability of the three largest Antarctic ice shelves and an improved estimate on the mass balance of the Antarctic ice sheet.
2: To understand change and improve predictions - Iceberg calving represents the largest but most poorly-estimated component of the mass balance of the Antarctic Ice Sheet. With improved knowledge of the calving process, we can improve ice sheet models and therefore better predict how the ice sheet will evolve in response to climate change.
3: Polar-global linkages -CRAC-ICE will contribute to our knowledge of freshwater fluxes to the ocean and influence on the thermohaline circulation, as well as frequency of calving events and ice shelf thinning and their possible impact on ice discharge, and thus on sea-level rise.
4: Investigating new frontiers -CRAC-ICE investigates rifting, calving, and iceberg melting and decay, which are all emerging as important but poorly understood processes. Anthropogenic CO2 sequestration due to iron-fertilisation of the upper Southern Ocean is considered as being feasible. Though the quantity still has to be determined, the dust input of icebergs to the upper ocean by strong melting, predominantly near the Polar Front, might already demonstrate the natural manuring of the euphotic zone.
5: The polar regions as vantage points -In the near future, clean freshwater might become a rare resource. Information about iceberg tracks and preferred sites of grounding and decay north of 60 S might support commercial efforts of iceberg “harvesting”.

2.3 Outline the geographical location(s) for the proposed field work (approximate coordinates will be helpful if possible)

2.4 Define the approximate timeframe(s) for proposed field activities?

2.5 What major logistic support/facilities will be required for this project?
Helicopters
Ice strengthened research ship
Fixed wing transport aircraft
Ice drilling capability
Snow terrain vehicles

Further details – For iceberg monitoring - satellites, iceberg buoys, ship observations by opportunity, and a central data depository.

2.6 How will the required logistics be supplied? Have operators been approached?

2.7 If working in the Arctic regions, has there been contact with local indigenous groups or relevant authorities regarding access?

top of page

3.0 STRUCTURE OF THE ACTIVITY

3.1 Origin of the activity
This activity is the start of a new programme that will outlive IPY

3.2 How will the activity be organised and managed? Describe the proposed management structure and means for coordinating across the cluster
Coordination of the project will be structured such that a “chair” and “co-chair” represent the former IPY-projects #21 and #249. Both are members of a steering group composed of a nominee from each of the project teams to formalise overall coordination and communication.
At the “sub-project” level each institute/PI is solely responsible for its dedicated ice shelf (Amery, Filchner-Ronne, Ross) or region of the Southern Ocean (Atlantic, Indian, Pacific). This allows for a regionally-focussed collaboration of teams combining the collection of satellite and field data, and the coordination of numerical model studies from ice shelf rifting to iceberg calving and iceberg decay. We expect no more than four of these teams. As icebergs might move from one to another region, communication across the teams is essential but will be easy to achieve due to a transparent matrix structure.
Due to the time-intensive work, logistical constraints in the field, and the high costs of image acquisition, we expect to split the workload among the participating nations/agencies/ institutes. Such partitioning requires a high degree of standardisation and communication between the groups, i.e., using common data formats and a joint or linked data depositories via the internet. This network can also be used for the exchange and depository of other data from other disciplines working in the Southern Ocean such as physical oceanography and biogeochemistry.
Coordination of the field work, adjustment of data acquisition, exchanges of data and software, and everyday communication will happen via the internet. A web-site hosted at one of the participating institutes will be maintained where participants can centrally post documents and reports for dissemination, and lodging them in a readily accessible on-line archive. Steering group meetings and/or workshops will be held at the beginning of the project as start-up and continue at annual to bi-annual frequency during international meetings such as AGU or EGU.

Results considering the dedicated region will be published by members of the related team, while general work encompassing the Southern Ocean, e.g., mass balance issues, will be published jointly.

3.3 Will the activity leave a legacy of infrastructure and if so in what form?
For ice shelf calving, no permanent infrastructure will be left since the rift network stations will be removed after the surveys. A suite of observation stations, however, will be available for follow-up projects, post IPY. For iceberg monitoring, the software for pattern recognition (also usable for sea ice), a central data depository, and a communication network will be installed. Due to the “natural cycle” of ice shelf front advance and retreat (its exact period yet has to be determined for each ice shelf), a long time series is necessary for well-founded conclusions which might push this part of CRAC-ICE beyond the IPY period by up to 20 years.

3.4 Will the activity involve nations other than traditional polar nations? How will this be addressed?
In the framework of a successful cooperation between AWI and the University of Rio Grande (FURG) polar oceanographers from Brazil (Prof. C.A.E. Garcia and Dr. M. Mata) will be involved conducting ship based observations and iceberg buoy deployments in the northwestern Weddell Sea.

3.5 Will this activity be linked with other IPY core activities? If yes please specify
We plan to coordinate our activities with IPY-EoI #607 "The State and Fate of the Polar Cryosphere", an activity covering the whole cryosphere, and to cooperate with IPY-EoI #577: “Evolution and Biodiversity in the Antarctic: the Response of Life to Change (EBA)”, a potential lead project under Cluster 1 “Life in Polar Regions: Patterns, Evolution, and Adaptation”, IPY-EoI #417: “Integrated analyses of Circumpolar Climate Interactions and Ecosystem Dynamics in the Southern Ocean - ICCED”, nominated as lead project under Cluster 5 "Biogeochemistry and Ecosystems", and with IPY-EoI # 237 “ANtarctic Studies of the Western Ross Sea (ANSWRS)”, a project under Cluster 5 “Coasts and Margins”.

3.6 How will the activity manage its data? Is there a viable plan and which data management organisations/structures will be involved?
The project will use the ICSU-WDC “Marine and Environmental Sciences” in PANGAEA as central depository for the data. Technical operation of the system is ensured by the Alfred Wegener Institute for Polar and Marine Research (AWI) and the Center for Marine Environmental Research (MARUM) on a long-term basis. Data will be stored in a consistent format with related meta-information in a relational database. The network between project partners will be established as a client/server system on the internet. The system is able store any parameter which has to be defined by the project. Data will be geo-coded in time and space allowing the extraction of any subset of data from the inventory. For the exchange of unpublished data through the internet during the project, it is possible to protect data sets by a password. Besides being a long-term operated archive, the system is a scientific tool to support the interpretation of comprehensive data collections and thus is well suited for this project.

Communication between the participants of the project and PANGAEA will be organized by a data manager who has to be funded by the project. Officially, the data once opened for public use will be archived, published, and distributed through the ICSU World Data Center for Marine Environmental Research (WDC-MARE, http://www.wdc-mare.org).

In addition, data will be stored at national depositories like National Snow and Ice Data Center (NSIDC), Australian Antarctic Data Centre (AADC), and the British Oceanographic Data Centre (BODC).

Data from the calving component of the project will include field data (GPS, Seismic, AWS, borehole, GPR), satellite imagery, and satellite altimetry.

3.7 Data Policy Agreement
Will this activity sign up to the IPY draft Data Policy (see website)
Yes

3.8 How will the activity contribute to developing the next generation of polar scientists, logisticians, etc.?
All aspects of CRAC-ICE will involve the education of students to receive different academic degrees (BSc to PhD). The involvement of universities/institutes from various countries will be used to facilitate the exchange of students including those from Brazil. Together with the joint assignment of technicians in the field this will teach young people the necessity (and advantage) of international collaboration when surveying polar regions. CRAC-ICE's remote sensing, field, and iceberg observation activities might also be attractive to students of the SCAR “International Antarctic Institute".

3.9 How will this activity address education, outreach and communication issues outlined in the Framework document?
CRAC-ICE is an ideal project for EOC, since iceberg calving appeals to the general public and media. We will develop teaching tools (websites, movies, presentations) and host school groups to learn about Antarctic iceberg calving. To articulate the social/economical aspects of iceberg research we plan as part of the “AWI School Project”, which teaches 11th and 12th grades in physics, chemistry, biology, maths, and English with great success, a focus for one semester on iceberg physics, chemistry, and biology. The material will be made public and provided free of charge to the participating teams for further use in their country. We will report major findings to our Communications Offices and National Committees for press releases.

3.10 What are the proposed sources of funding for this activity?
We anticipate logistical and financial support from national agencies like ARC/AAS (Australia), PROANTAR (Brazil), BMBF and/or DFG (Germany), NERC (U.K.), and NSF (U.S.A.), as well as from various Space Agencies, particularly ESA, CSA, and NASA.

For Amery Ice Shelf, H. Fricker and R. Coleman will seek logistical support from AAD and financial support from NSF, ARC and AAS. For Ross Ice Shelf, D. MacAyeal and T. Scambos will apply to NSF. Filchner-Ronne Ice Shelf funding is TBD.

3.11 Additional Comments

top of page

4.0 CONSORTIUM INFORMATION

4.1 Contact Details

Lead Contact
Dr Hartmut Hellmer
Alfred Wegener Institute for Polar and Marine Research
Bussestr. 24 Bremerhaven
27570
Germany

Tel:          +49 471 4831 1794
Mobile:   N/A
Fax:         +49 471 4831 1797
Email:       hhellmer@awi-bremerhaven.de

Second Contact
Dr Helen Amanda Fricker
Scripps Institution of Oceanography
9500 Gilman Drive La Jolla
CA 92093-0
USA

Tel:          +1 858-534-6145
Mobile:   +1 619-993-3569
Fax:         +1 858-534-2902
Email:      hafricker@ucsd.edu

4.2 Other significant consortium members and their affiliation