Tracking and prediction of the path of the Giant Pine Island iceberg

Since November 2011 it has been known that a giant iceberg, some 30 km long, is likely to break off Pine Island glacier (75S, 100W) into the Amundsen Sea off west Antarctica in the near future. This has now occurred (9 July 2013) and the iceberg will soon begin to move westwards in the Antarctic Coastal Current towards the Ross Sea. This is the first such giant iceberg to calve from Pine Island glacier since 2001. Its likely initial trajectory, at first sight, does not raise environmental issues apart from a slow and persistent increase in the freshwater flux around west Antarctica, an area without major deep water formation. However, a previous giant iceberg from this location eventually joined the Antarctic Circumpolar Current (ACC) and passed through the Drake Passage, entering the South Atlantic and so potentially posing both a navigation hazard and a source of upper ocean freshwater close to regions of significant deepwater and intermediate water formation.

In this Urgency proposal we intend to track this iceberg, but, more importantly, to also predict its likely path and environmental impact beyond the duration of a grant, as its lifetime is likely to extend over years rather than months. We will use the ITSARI ice tracking software algorithm, developed at the University of Sheffield, to track and describe the evolution of area (and break-up) of the giant iceberg, and the coupled ocean-iceberg model NEMO-ICB, developed at the University of Southampton, to predict the iceberg's path over months to years.

We anticipate that this will provide a timely warning of any navigation or oceanographic consequences of the iceberg's release, but also test a technique for later implementation by ice hazard warning services.

We envisage two main non-academic beneficiaries of this proposal. The first of these is the shipping industry using the Southern Ocean, and associated agencies/companies providing an ice warning service. The second is the general public, who will be interested in the fate of this Giant iceberg, larger than Manhattan in area.

Ways in which potential beneficiaries may make use of the research
1. Ice hazard forecasting groups and forecast users
If the PIG iceberg penetrates the Southern Ocean shipping lanes, or moves towards Antarctic research bases, it will present a distinct maritime hazard, particularly as the iceberg begins to break up. This project, in attempting to predict the movement of the PIG iceberg, has the potential to contribute to ice hazard services of government and industry (e.g. British Navy, oil industry, shipping lines). Currently, they work on a very short timescale, mostly reporting ice positions, with minimal prediction. However, the PI (Bigg) is involved in a standing cooperation with one of these agencies, Kongsberg Satellite Services (KSat), as his SAR remote sensing algorithm is already deployed for operational use by KSat to help their navigation hazard service, and developing activities in managing ice hazards for stationary platforms in polar oceans. The PI (Bigg) is aware of their interest in longer-term ice hazard forecasting. Their current focus is mainly directed to Arctic waters, but they have an Antarctic satellite receiving station and previous discussion has included Southern Ocean problems (e.g. an unsuccessful 2008 ESA application "Bergwatch: iceberg monitoring service for the Southern Ocean"). As NEMO has recently been adopted as the Forecasting Ocean Assimilation Model (FOAM) for global deep-ocean applications at the UK Met Office, part of the wider National Centre for Ocean Forecasting (NCOF) that includes NOCS, verifying that NEMO-ICB has the potential for success as an ice hazard forecast tool can add to this capability.
If this proposal were to be successful a follow-up proposal, developing from our existing user cooperation with KSat and the Met Office, will be submitted to consolidate the Impact potential of this work. This service is based on sea-ice tracking, but here we will be testing extension of the sea-ice algorithm to icebergs on a large scale. There will also be capability for NEMO to forecast iceberg density and individual iceberg tracks, which will aid shipping and marine platform hazard assessments further. As part of the Impact budget we therefore ask for one trip to both KSat (Bigg) and the Met Office (Marsh) towards the end of the project to discuss further development of a forecasting service.

2. General Public
Marsh is active in public engagement, having given a public lecture on icebergs to publicize the 10 April 2012 opening of the "Sea City" museum, based in Southampton's Civic Centre. He also provided material and quotes for a museum exhibit on icebergs, part of an exhibit, "Titanic: The Legend". Bigg and Wilton currently have an article under review with "Weather" developing this Titanic theme of our work.

As part of the raising of public awareness of the impact of giant icebergs we will establish a web-site, based at Southampton, showing the PIG iceberg predictions, accompanying this with a press release. While for this project such a website will perforce be active for a short time only, a follow-up proposal would seek to strengthen this impact component.