Arctic ocean predator confidential



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                  1. Svalbrd Coastal Approach

                  2. Approaching Svalbard 's calving glaciers.



The Governor of Svalbard recommends that all sailors keep a distance at least 200 meters from the fronts of the calving glaciers in Svalbard.

The Norwegian Polar Institute has, after an assignment from the Governor of Svalbard, written a report where the main conclusions are that it is impossible to predict when calving may occur, how large a block will be created, or how it will enter the water. 200 meters is a safe minimum distance, for avoiding both direct hits and the largest waves. At some glacier fronts even this is too close and the Governor advices the captains and tour operators to make a specific risk assessment whenever approaching a glacier front.

 

The two main conclusions are:


• At the level of individual events, calving is a random process. It is impossible to
predict precisely when calving may occur, how large a block will be created, or how
it will enter the water.
• 200 m is a safe minimum distance, with a good margin for safety, for avoiding both
direct hits and the largest waves.

Furthermore:


• Using calving cliff height as an estimator for the MSD is inadequate since the hinge
point can lie beneath the waterline. In addition, submarine calving events can bring
large ice blocks much farther out than the calving cliff height.
• Waves that are created closest to the block, in the so-called splash zone, are very
large, unpredictable, and dangerous, particularly for small boats. The MSD for
avoiding direct hits from ice blocks needs to be larger to ensure that vessels are
outside of the splash zone.
• Outside of the splash zone, waves become coherent, and can be ridden out. However,
as waves become grounded, either in shallow water, or on shore, tsunami waves are
created.
• Small boats should not land on shores near the edge of calving cliff faces.
• The 200 m distance should be increased in narrow fjords, in shallow fjords, or
locations with ice cliffs higher than 40-50

(05/01/2009)



Contacts

  • Stein Tore Pedersen, Tlf.               79 02 43 23         79 02 43 23



  1. WEATHER

    1. General Weather and climate in Svalbard10


Despite of Svalbard being so close to the North Pole, the archipelago has arelatively mild climate compared to areas at the same latitude. In Longyearbyen, the average temperature ranges from 14 degrees Celsius below zero during winter to 6 degrees Celsius above zero during summer. The lowest temperature was measured in March 1986 at 46.3 degrees Celsius below zero - the highest temperature was measured in July 1979 at 21.3 degrees Celsius.

During winter Svalbard often has long periods with temperatures between 20 and 30 degrees Celsius below zero; add to that a wind-chill factor that usually seriously compounds the cooling effect of the low temperatures. During summer it is common with periods of fog. In terms of precipitation, Svalbard may be described as an "arctic desert"with annual rain- and snowfall at a mere 200 - 300 millimetres.



The weather on Svalbard can shift very quickly and local variations are often considerable.

    1. Polar Sea view – Ice Charts11





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