Ten days ago, the grinding slow-motion rivers of floating sea ice flowing around Canada's Arctic archipelago claimed the lives of Marc Cornelissen and Philip de Roo, seasoned Dutch polar trekkers combining an adventurous spirit with environmental activism and citizen science.
After several recovery efforts were aborted due to foul weather and unstable ice, one body (as yet unidentified) was retrieved on Friday, Canadian police said. But there is little closure for loved ones, and the loss of these men still reverberates through the environmental organizations that supported their work and among polar scientists whose research was aided by the data they collected. Read on for input from scientists who worked with them.
To anyone who's spent time on Arctic sea ice (including me), the tragedy is also a sobering reminder that even the most carefully mounted forays in this unforgiving region come with unpredictable risks.
On April 6, Cornelissen, 46, and de Roo, who had just turned 30, had skied out of Resolute Bay, a stopping point for dozens of Arctic explorers and scientists, bound across the ice for uninhabited Bathurst Island, where they were to be picked up on May 4. Along the way, their plan was to collect measurements of snow and ice thickness that could help improve the accuracy of estimates made in the region by satellites and aircraft.
Daily audio dispatches from Cornelissen were posted on his Cold Facts website, Facebook and Twitter. The project was also aimed at raising public awareness of Arctic climate change.
Cornelissen's efforts were largely funded by WWF (known as the World Wildlife Fund in the United States) but he had worked over the past decade with scientists from the European Space Agency and the U.S. Army Corps of Engineers Cold Regions Research and Engineering Laboratory as well as several universities.
The two-man expedition (with a loaned husky as a polar bear watchdog) was called the "Last Ice Survey" because the maze of passages between that part of Canada and northwest Greenland is projected to remain mostly ice covered even when much of the Arctic Ocean becomes open water in late summer in coming decades. (As I've noted, scientists have wisely been proposing that special conservation plans be developed in that region for polar bears and other wildlife dependent on sea ice.)
Early coverage by The Guardian provides chilling details, but Cornelissen's audio dispatches are the most haunting record of events, particularly the April 28th message one day before an automated distress signal triggered a search:
"A good day in the end. It was a strange day. We started with a little overcast and a cold winds, which picked up. So we thought that's the theme; let's dress up a little more. We could see in the northern section some 'water skies,' which is a sort of localized grayish line in the horizon that points toward open waters so we knew to avoid that.
"So we skied north and west. Within [50 or 15] minutes of skiing it was getting really warm, so it became really untasteful because in the end it was me skiing in my underwear only, and my boots, of course.
"And it's very good that you guys don't have pictures from the ice. I don't think it would have been very nice or sexy either. But it was the way to deal with the heat. It was amazing. Felt like 0 degrees, minus 3 or 5 — something close to that. Too warm, actually.
"And we made some good progress and actually we're nearing into the coast of Bathurst…. Tomorrow we might just go ahead and turn north before hitting the coast because we think we see thin ice in front of us. Which is quite interesting.
"Quite smooth and thin ice [Inaudible]. And we're going to research some more of that if we can. So today was a good day. We're totally exhausted and ready for a sleeping bag actually, some more hot chocolate and we'll call it a day."
Then came the distress call, and dark news, followed quickly by shocked laments.
My condolences go out to the family and friends of Cornelissen and de Roo. They were part of a small and remarkable community of tough, determined explorers and researchers for whom the poles are almost unavoidably magnetic.
For more on the data-gathering effort by Cornelissen and de Roo, I reached out to Christian Haas, the Canada Research Chair for Arctic Sea Ice Geophysics at York University, who worked with Cornelissen on this expedition and previous projects.
I asked him to characterize his interactions with Cornelissen over the years:
"I have known Marc for more than 10 years and supported him in his tireless efforts to contribute to our own data gathering efforts. Even today's well funded research organizations cannot do research everywhere and at any time, and therefore any additional systematic information gathered by polar travelers can be highly complementary. The challenge is to provide these on sufficiently large scales, and Marc was attempting to address that challenge. He also aspired to set standards his fellow explorers could follow to provide date themselves. Also in-situ measurements of snow and ice thickness are required to validate airborne and satellite measurements. There is no other reliable method to measure the thickness of snow than to step on the ice and use poles like Marc did.
"Of course the event is tragic and very sad. They were within 600 meters of reaching land and safety, and headed directly to a small polynya, a region of open water or thin ice. The ice would have been perfectly safe to travel just a few kilometers to the north or south. However, this region is known for its strong currents which bring warmer water from deeper down up to the surface and thus erode the ice from underneath."
In contrast to some media reports implying that the conditions creating dangerous ice in the area were related to global warming, Haas added this:
"The accident has nothing to do with climate warming or the last ice. The ice in this region of approximately 100 kilometers in diameter is always thinner than the surrounding regions, and small areas of open water are common year-round. In fact, our own airborne ice thickness surveys just north of this region have shown that the ice is (still?) very thick, ranging from over two meters for first-year ice to over three meters for multi-year ice. The events have changed nothing to the fact that this region will most likely be the last ice area."
Bruce C. Elder, a sea ice scientist at the Cold Regions Research and Engineering Laboratory, worked with Cornelissen and Haas last year on an international ice study called CryoVEx. He sent these remarks:
"Satellite data is only valid as long as you have documented that it is accurate — or at least can explain the accuracy and resolved uncertainties with the data set. In the spring of 2014 we were part of a program that performed some ground-truth measurements to validate aircraft sensors and thus moving up the scale to satellite data. For this purpose — combined with a couple other programs — we took ice-based measurements that were then overflown by various aircraft with downward looking sensors, which in turn flew missions beneath the polar-orbiting satellite track.
"It is very important to periodically perform these ice-based experiments so that you have confidence in what the sensor-based electronics is actually showing you. If you oversimplify things, the most accurate measurement of snow and ice thickness is done by being there — on the ice — drilling a hole and directly measuring it. There is no calibration or interpretation needed.
"The team, which Marc led and provided the logistical support for, deployed from Resolute to Nord Greenland before setting up a rustic field camp on the sea ice for six days, during which time we mechanically drilled the ice to measure thickness, measuring snow depth in a grid pattern along the flight lines as well as dragging instruments along the surface that produced the same measurements for comparison to the airborne data.
"To do this well you need to conduct these calibration lines over various ice types and snow depths. The different ice types do not all exist out of a single location, so for the 2014 measurements, we chose the area north of Greenland to produce thick multi-year ice with a thick snow cover. Simultaneously, the same measurements were taken colleagues near Barrow, Alaska, where the conditions are first-year sea ice with thin snow cover.
"For our expedition, Marc and Petter [Nyquist] were in charge of logistics, safety and cook for our remote field camp of six researchers.
"He was a caring person — well versed in operating on sea ice. At times, Marc and Petter would bring food and hot beverages out to our research sites up to a mile away as he thought we were pushing too hard and needed take a break.
"We were all working long hours and his caring, knowledgeable support was instrumental in us retrieving such a complete data set in very limited time."