This article was published in the publication "Safety - status and signals 2011-2012".
These form when glaciers calve (big bits break off into the sea). Being salt-free, their ice is particularly hard.
Roughly 100 bergs are afloat at any given time in the northern Barents Sea, between Svalbard and Bear Island.
They follow the currents south and usually ground on Bear Island or flow around it and then northwards.
Only two cases of bergs reaching the Norwegian coast are known, from 1881 and 1929 respectively. On both occasions, they were spotted off eastern Finnmark county.
Norway’s Norsok N-003 industry standard gives rough estimates of the 100-year and 10 000-year limits for iceberg movement. The Skrugard discovery, for instance, lies within the 10 000-year boundary.
This comprises two main types: multiyear and first-year.The latter contains more salt and is not as hard as older ice, but drifts further south.
Once again, Norsok N-003 gives rough 100-year and 10 000-year estimates for how far south drift ice is likely to get. The Snøhvit and Goliat fields are close to the 10 000-year boundary.
Possible off shore developments within the relevant boundaries would call for measures to be considered to deal with icebergs or drift ice.
These could include dimensioning installations to withstand collisions – the approach taken on the Hibernia field off eastern Canada, for instance.
Another solution could be to utilise subsea installations. It might also be relevant to tow icebergs away from a collision course.
Winterisation of facilities – equipping them to cope with severe cold – will also be carefully assessed asoperations move further north.