Guest post by David Middleton
A precious collection of ice cores from the Canadian Arctic has suffered a catastrophic meltdown. A freezer failure at a cold storage facility in Edmonton run by the University of Alberta (UA) caused 180 of the meter-long ice cylinders to melt, depriving scientists of some of the oldest records of climate change in Canada’s far north.
The 2 April failure left “pools of water all over the floor and steam in the room,” UA glaciologist Martin Sharp told ScienceInsider. “It was like a changing room in a swimming pool.”
The melted cores represented 12.8% of the collection, which held 1408 samples taken from across the Canadian Arctic. The cores hold air bubbles, dust grains, pollen, and other evidence that can provide crucial information about past climates and environments, and inform predictions about the future.
The storage facility is normally chilled to –37°C. But the equipment failure allowed temperatures to rise to 40°C, melting tens of thousands of years of history. Among the losses: some of the oldest ice cores from Mount Logan, a 5595-meter-high mountain in northern Canada. “We only lost 15 meters [of core], but because it was from the bottom of the core, that’s 16,000 years out of the 17,700 years that was originally represented,” Sharp says.
Scientists also lost 66 meters of core from Baffin Island’s Penny Ice Cap, which accounts for 22,000 years—a quarter of the record. That leaves “a gap for the oldest part, which is really the last glaciation before the warming that brought us into the present interglacial,” Sharp says.
Apparently the meltdown was due to
two three malfunctions:
Investigation points to two malfunctions
An investigation into the freezer malfunction found fault with the cooling system. Specifically, the refrigeration chillers shut down due to “high head pressure” conditions. Essentially, the chillers were not able to reject their heat through the condenser water system—heat instead of cold circulated through the freezer.
Compounding matters, the system monitoring the freezer temperatures failed due to a database corruption. The freezer’s computer system was actually sending out alarm signals that the temperature was rising, but those signals never made it to the university’s service provider or the on-campus control centre.
In the short term, refrigeration technicians are monitoring the freezers through twice-daily checks, Sharman said. The computer database corruption was resolved by adding a second monitoring controller, which is now issuing real-time messaging updates every eight hours.
- The “chillers” circulated heat through the freezer.
- Database corruption prevented the alarm signals from reaching their destination.
- The failure to visually inspect the freezers on a daily basis before 1 & 2.