With rugged red mountains rising on either side, a sailboat carrying scientists deftly snakes between icebergs brimming Greenland’s Scoresby Fjord, as they rush to document this understudied region on the frontline of climate change. After the warmest July ever recorded at Summit Camp atop Greenland’s ice sheet, the expedition members sailing the country’s east coast are acutely aware of the urgency. “The risk that we have here is the disappearance of the complete ecosystem,” Eric Marechal, director of research at the French National Centre for Scientific Research (CNRS), tells AFP on board the sailboat Kamak. In addition to the icebergs — which in some areas blanket over half of the fjord — the scientists also need an armed escort to protect against polar bears. But for the researchers, facing the harsh environment is a risk worth taking for rare access into one of the world’s most isolated ecosystems. “We see that global warming is really entering a strong phase here. So we need to document that,” says expedition leader Vincent Hilaire. The expedition, arranged by the volunteer-run French initiative Greenlandia, aims to understand climate change’s effects on Scoresby Fjord and its inhabitants. Frozen in ice for eleven months of the year, the planet’s largest fjord system, which remains vastly understudied, is a challenge to maneuver even for a seasoned crew.