The frigid northerly routes will be much more accessible than ever expected, UCLA researchers reported.
"The development is both exciting from an economic development point of view and worrisome in terms of safety, both for the arctic environment and for the ships themselves," lead researcher and geography Professor Laurence C. Smith said.
By mid-century shipping vessels will be able to navigate previously inaccessible parts of the Arctic Ocean and will not need icebreakers to clear they way as they do today, the researchers said.
"We're talking about a future in which open-water vessels will, at least during some years, be able to navigate unescorted through the Arctic, which at the moment is inconceivable," co-author Scott R. Stephenson, a geography doctoral candidate, said.
With global warming, the ice sheets may become so thin polar icebreakers will be able to navigate between the Pacific and Atlantic oceans by making a straight path over the North Pole, the researchers said.
"Nobody's ever talked about shipping over the top of the North Pole," Smith said. "This is an entirely unexpected possibility."
However, they said, even with global warming arctic access will not last beyond late summer.
"This will never be a year-round operation," Smith emphasized.