Underwater microphones to record the melting of icebergs

An expedition of scientists and an artist are deploying underwater microphones in the ocean off Greenland to record the sounds of melting icebergs, The Guardian has reported. 

Over the next two years, the hydrophones will capture the sounds of melting Arctic sea ice and under subaquatic audio every hour, being lowered to different levels and temperatures to record earthquakes, landslides, wildlife, pollution and meltwater, creating an archive of the “ocean’s memory”.

The recordings will be used in scientific research, as well as in a mixed-media installation to explore human impact on the world’s oceans, the newspaper reported.  

“I’m interested in hearing the acoustic pollution,” the artist said. “The sea levels are rising and that will have an impact I’d imagine on the sound range and on all the biodiversity.

The expedition has deployed five moorings with hydrophones – and 12 moorings in total – in the Davis Strait, an Arctic gateway between Greenland and Canada.

McDonald has been accompanied by 21 scientists from Europe, the US and Canada on her four-week-long trip. During the expedition, the team studied sea salinity, whale migrations, ice floes and other phenomena, with less-than-ideal weather conditions.  

The expedition experienced strong wind, rain and snow and coincided with the calving of the Nuup Kangerlua glacier.

In two years’ time, McDonald plans to work with a composer to incorporate the recordings into an acoustic installation, which will be accompanied by paintings, sculptures and other works based on the trip.

“Sound is fundamental in the ocean and Arctic animals,” she said. “Hearing is fundamental to communication, breeding, feeding and ultimately survival. It speaks of the necessity of paying attention to the pollution we are causing to the ecosystems around us.”

The expedition experienced strong wind, rain and snow and coincided with the calving of the Nuup Kangerlua glacier. The researchers are to return to the port of Nuuk, in western Greenland, on 22 October.

Global warming has significantly increased the likelihood of extreme weather events, and scientists have, for decades, warned about the dangers of sea-level rise caused by the melting of the ice sheets. 

When it comes to Greenland, scientists have predicted that global warming will cause a minimum rise of 27cm (10.6in), according to a recent study in the journal Nature Climate Change. A separate study last year found a significant part of Greenland’s ice sheet was on the brink of a tipping point, after which accelerated melting would become inevitable even if global heating is halted.

“The collapse of the Greenland ice cap is one of the tipping points I am working with, a time that may already have passed,” said McDonald, who visited  Greenland in 2017.

“One major thing we discovered is that way up high here in the Arctic life is still thriving. Although the seascape may look barren, it is alive with possibilities. Some of the hydrophones from another expedition came back looking like alien creatures shuffling out of the Greenland ocean. Lichens and tiny plants were living in symbiosis with rusted surfaces.”

Recent research from Brown University showed that unless global leaders successfully constrain warming to 1.5°C over the next 43 years, climate change will likely open up several new routes through the Arctic by the middle of this century.

The expedition has been funded by the US National Science Foundation’s polar programme. The researchers are to return to the port of Nuuk, in western Greenland, on 22 October.