The most direct shipping route from Europe to Asia is fully clear of ice for the first time since records began, the European Space Agency (Esa) says.
Historically, the Northwest Passage linking the Atlantic and Pacific Oceans has been ice-bound through the year.
But the agency says ice cover has been steadily shrinking, and this summer's reduction has made the route navigable.
The findings, based on satellite images, raised concerns about the speed of global warming. Read More