How do we know what happens over the lifetime of an iceberg? By placing a GPS tag on an iceberg, we can get a rare glimpse into its journey – and a chance to improve forecasts of iceberg trajectories. That’s important in a warming Arctic, and where shipping and tourism are predicted to increase.
In the icy waters off Greenland, two very different teams have been busy tagging icebergs this summer. One is a polar guide leading tourists through the remote Melville Bay. The other is Professor Lars Henrik Smedsrud from the University of Bergen, working much further south in Disko Bay. What they have in common is a shared mission: helping researchers at the Nansen Center improve how we forecast the movement of icebergs, while carrying out their own work.
Both expeditions are voluntary contributions to the ACCIBERG project, led by the Nansen Center. In ACCIBERG, researchers work with improving forecasts of icebergs and sea ice. The models that produce such forecasts rely on numerical simulations and fed by satellite data –but to know if they’re working, researchers need something more down-to-earth: real-world data.
“We cannot get much confidence in a forecast without proper ground truth,” says project leader and research leader at the Nansen Center, Laurent Bertino. “That’s where these iceberg tags come in”.
There are currently very few records of icebergs’ behaviour; there are some sporadic scientific campaigns, often in limited geographic areas and some really large icebergs are followed up by satellite, and although more data does exist in private industries, it is not publicly available. So ACCIBERG has called up volunteers from groups venturing into iceberg-infested waters this season, to help validate the simulations of iceberg drift and deterioration.
One of the tagged icebergs, nicknamed Juliette, is now drifting through the islands northwest of Greenland. It was tagged by Nicolas Dubreuil from SEDNA Expeditions, who brought the GPS sensor along while guiding tourists. This area of Greenland has numerous icebergs, the larger ones can be detected by satellite (see the dots in this map), but no data currently exists on their movements. Local hunters were involved in the deployment indicated by experience which iceberg would be safe to climb, which one would be on the move and how to protect the tags from the kleptomaniac ravens.
Much further south, in Disko Bay, Professor Lars Henrik Smedsrud and his team from the University of Bergen tagged a dozen more icebergs. The data from these tags are now streaming into the IABP server hosted by the University of Washington – and into the hands of the ACCIBERG team.
This kind of data is gold for researchers. It helps them test and fine-tune their models, making forecasts more reliable. That’s especially important in a warming Arctic, where sea ice is retreating and icebergs are becoming more mobile – and potentially more hazardous to shipping and infrastructure. The iceberg forecasts that ACCIBERG is developing will be valuable in an Arctic where shipping and tourism are predicted to increase.
The Nansen Center has long been at the forefront in Arctic research, and ACCIBERG is one of several projects where we play a central role in developing tools that combine satellite data, field observations, and advanced modelling. The iceberg tagging effort is a small but powerful example of how collaboration – across disciplines and even with non-experts – can push science forward.
And as Juliette continues her journey, she is not just drifting aimlessly. She is helping scientists build better tools to understand a changing Arctic.
