Arctic ice reflects sunlight; its absence may accelerate global warming. The intricate chemistry that occurs in the rich Arctic waters could go haywire with unaccustomed heat and sunlight. “People tend to think there’s not much life in the Arctic. But it’s an incredibly diverse ecosystem,’’ says Gary Stern, the chief scientist on the Amundsen. He was aboard when the ship was deliberately frozen in Franklin Bay in 2003. They spent the long winter doing experiments on the ice.

This year is “amazing. No ice,’’ Stern says.

Estimates vary widely on when the passage will be open to shipping all summer because of the ceaseless warming. The Canadian Ice Service conservatively predicts the southerly drift of even a shrunken ice pack will keep the passage clogged for most of this century. Other experts predict it will be open as soon as 2020; Canada’s defense agency says 2015. Those who visit regularly say the evidence is before their eyes. “You can see it. You come every year and you see less and less ice,’’ says Marie Emmanuelle Rail, 30, a researcher who has been working in the Arctic for five years.

ArcticNet, the Canadian university consortium organising the voyage, believes the interwoven effects of global warming may be revealed as shipmates discuss their work. The vast Arctic out the portholes is a constant reminder of the stakes. “It’s huge. It’s all about saving the world,’’ says Stephane Thanassekos, 26, a French researcher pursuing his doctoral degree at Laval University in Quebec.

A scientist with infectious enthusiasm, Thanassekos operates a contraption that looks like an automatic milker from a dairy barn. His work calculates the survival prospects of Arctic cod. ``which are right in the middle of the food chain’’ of the Arctic.

Jody Deming, 54, a professor at the University of Washington, studies “hot spots’’ in the ocean that are now being overtaken by a gradual warming, and microbes in ice that may help reveal life in space.

Stern, 47, is trying to figure out how mercury and other chemicals are making their way into animals of the Arctic.

Doug Struck