Press Release: Sea ice thickness measurements crucial for Arctic shipping forecasts

Published: 29 Oct 2014

Declining levels of summer sea ice in the Arctic have opened up the region for commercial shipping and tourist cruises when the ice is at its lowest. In order to reliably predict safe and accessible shipping routes throughout the Arctic region measurements of the thickness of sea ice must first improve.

While current satellite technology (e.g. European Space Agency’s CryoSat2 spacecraft) is able to calculate sea ice thickness, the measurements required during the summer months cannot be made accurately enough for advance forecasting as pools of melted water on the surface of the ice confuse its on-board instruments.

Lead scientist Dr Jonny Day from the University of Reading said,

“Global warming is heating up the Arctic and the amount of summer sea ice in the Arctic is much reduced compared to a few decades ago. This has opened up not only new potential shipping routes, but the possibility that energy companies could get access to vast oil reserves, thought to be buried below the ocean floor.

“Because sailing through sea ice can be dangerous, slow going and consume large amounts of fuel, shipping companies may benefit from accurate advance warning of where the sea ice is going to melt, to show where the open water will be or where icebreakers could force their way through.

“This would require more accurate forecasts than scientists can currently provide. We’ve now shown with our modelling that information about the thickness of the ice is crucial to providing better forecasts several months in advance. But even the latest satellites are incapable of reliably providing this information between May and October, when end users are most in need of good forecasts.

“Finding a way to fill this gap may require new satellite technology or measurement techniques, which could still be years away.”

Co-author Dr Ed Hawkins, also from the University of Reading, said,

“While we have highlighted a gap in our ability to make reliable forecasts at the moment, better measurements of sea ice thickness could improve forecasts.

“Satellites have revolutionised our understanding of the poles, but they still can’t measure everything from hundreds of miles above the surface. We need a diverse array of technologies to provide the whole picture – from improved satellites to old-fashioned manual measurements.”

The rapidly declining levels of ice in the Arctic has led to a growing scientific interest in Arctic ice forecasts.  One system, recently developed by a University of Reading team led by Professor Daniel Feltham, used the number of melt ponds – problematic for satellite measurements of ice thickness – to predict the minimum summer extent of sea ice several months in advance with an unprecedented level of accuracy.  But even this system is incapable of making predictions showing where and when the ice will melt with the precision required for shipping.




The research was carried out by scientists at the National Centre for Atmospheric Science (NCAS), at the University of Reading, and published in the journal Geophysical Research Letters.

J. J. Day, E. Hawkins and S. Tietsche (2014) ‘Will Arctic sea ice thickness initialization improve seasonal forecast skill?’, Geophysical Research Letters, DOI: 10.1002/2014GL061694

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For more information contact Pete Castle at the University of Reading Press Office

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