Merchant vessels do not transit from Europe to Asia via the N/W passage this feat has only been accomplished by a handfull of vessels , mostly adventurer's or special expeditions , other than that most transits are done by Coast Guard icebreakers on science missions. Merchant shipping is confined to bulk carriers picking up ore from mines that operate year round and stockpile their ore that is shipped out during the short summer shipping season and even then they require Coast Guard icebreaker assistance. The other shipping into the Arctic is the summer resupply ships to artic communities and this is run from B.C. for the western arctic & the east coast for the eastern arctic and they very seldom if ever make a transit. Global warming may change all that in future but as of yet ice conditions make full transits too dangerous. Some years ago the US Coast Guards most powerfull icebreaker at the time damaged her propellors in ice and had to be assisted by a Canadian Coast Guard icebreaker to get out. When the fall comes all shipping leaves the arctic to the US,UK & Russian nukes, the Aurora's and recco satellites.
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