Fire dancer Afi has more reason for concern about global warming than most in the novel y1. His home nation of Kiribati is composed of a series of atolls that rise only a few meters above sea level in the very middle of the vast Pacific Ocean. Sea level rise that is too rapid to allow coral to respond naturally means that Kiribati, Tuvalu and several other countries face becoming totally submerged over the next several dozen years. This is in real life, you understand, not fiction from the book
However, word today is that there will be new places to sail. According to a study conducted at UCLA, by 2050 the Arctic ice sheet will be thin enough for icebreakers to carve a path between the Pacific and Atlantic Oceans and to possibly allow commercial craft to travel right over the north pole.
According to the USA Today the new research is being published online in the journal of the Proceedings of the National Academy of Sciences. The earliest that sea routes would go directly over the North Pole would be in the 2040s, according to Laurence Smith, a geography professor at UCLA who headed the study, and who notes that this scenario is likely to occur at this point whether global warming is curbed soon or allowed to continue to increase.
Of course, the earth has and will continue to undergo radical changes in the shape of its continents and oceans. About 200 million years ago all the continents got together for awhile and had a party that we refer to as Pangaea. However, the earth does have its own pace. It took tens of millions of years for that that party to end.
The UCLA study notes that this unexpected effect of global warming would make for significantly shorter shipping routes but would also obviously raise a host of political and ecological issues. Not to mention the fact that we will need to find a new remote location for Santa Claus.