We are so used to negative news about climate change it is a little hard to process this.

The Arctic ice melt is creating a "new normal" in the far northern marine ecosystem that has created conditions for a whale population boom.

Biological oceanographer Dr Sue Moore from the US Pacific Marine Environmental Laboratory in Seattle said that the loss of sea ice in late northern summer means that "ocean habitat for cetaceans has expanded".

Her article, published on Wednesday in the Royal Society's Biology Letters notes that the region north of the Bering Strait between Alaska and Russia has "lost 75 per cent sea ice by volume and 50 per cent in late-summer surface cover".

This has meant an "extension of the open-water period" in the region by four to six weeks each year.

As these northern waters have warmed, phytoplankton population has grown by more than 50 per cent in the Beaufort Sea. This has, in turn, supported an increase in mesozooplankton and forage fish, upon which baleen whales prey.

In aerial surveys from 2009 to 2012 humpback, fin and minke whales where observed in areas where none had been seen from 1982 to 1991.

The calls of the humpback and fin whales have been recorded in waters as late as November in areas they previously were unknown.

Dr Moore said that this will result in population increases for these whales, "many of which are recovering in number from severe depletions from commercial whaling in the 19th and 20th centuries".

The growth in their numbers will also help stabilise the changed ecosystem, she said.

"Baleen whales act as ecosystem engineers and their recovering numbers may actually buffer the marine ecosystem from destabilising stresses associated with rapid change," she said.

However, it is by no means all good news.

Many other marine mammals are suffering from the loss of Arctic ice.

Dr Moore said: "Polar bears, walruses and ice seals appear to be particularly vulnerable because they rely on sea ice as a platform for key life-history functions, such as birthing, nursing young, hunting and resting."

A study published earlier this year showed an increase in polar bears taking longer and more perilous swims.

"Ice is changing so quickly that we're finding the bears are getting caught in places where they're finally coming to the realisation, 'I just can't stay here'," said Dr Andrew Derocher, the study's author.

Dr Derocher said the number of bears making long swims was directly proportional to the loss of sea ice in the Beaufort Sea, where the study of more than100 bears was done.