Bremerhaven, Germany — Three hundred scientists have been training in sub-zero temperatures in preparation for the trip of a lifetime. They will spend months trapped in sea ice, as part of a year long Arctic expedition, called MOSAiC, studying the effects of climate change. The expedition sets off from Norway on September 20.

"We are looking at creating a whole picture of what the Arctic is going to do in the coming years," said Alison Fong, who heads up MOSAiC's ecosystems research team.

Polar bears are a major concern, and she might have to swap her microscope for a rifle scope.

"All of our scientists are trained in polar bear safety, which includes carrying a rifle for protection. When we work in remote sites on the ice, we will take small electrical fences with us and personnel carrying rifles and flare guns and other types of safety equipment," Fong said.

Home base is a German icebreaker, the Polarstern. It will be fitted with scientific equipment, turning it into a floating laboratory.

What happens in the Arctic doesn't stay in the Arctic. It's generally considered an early warning system for the impact of climate change, and scientists are hoping the expedition on this ship will raise their understanding of it to a whole new level.

Getting a taste of what lies ahead, the scientists practiced using a remotely controlled device which measures light through the ice, and drilling through the core to assess ice thickness.

The Arctic is warming faster than anywhere else on Earth but scientists have never been able to conduct research in the remote northern parts of it during winter. Now they will attempt an unprecedented scientific mission. The crew will sail close to the North Pole, cut the engine and wait for water to freeze around the vessel. They will then simply drift with the ice flow.