Monitoring of Arctic Ice by Passive Acoustic Monitoring – GAAP

Arctic is faced with global warming. The melting of the arctic pack ice and ice cap is dramatically changing the conditions of life for animals and humans. New territories are free for economical activities such as shipping or exploitation of offshore tanks of oil and gas. Arctic focuses environmental, societal and economic issues.

The goal of GAAP is to develop Passive Acoustics Monitoring of the arctic ecosystems.

GAAP aims at producing additional information versus more traditional monitoring technics such as satellite imagery : PAM is local, continuous in time and give an integrative environmental point of view (from biotic, abiotic processes to anthropogenic activities).

The goal of GAAP are twofold. First, GAAP will monitored the ice dynamics and events (pack ice cracks, calving of icebergs and their drifts in the ocean) for security of human activities. Second, the same acoustics sensors used for ice monitoring will be used to monitor the surrounding ecosystems via their biophony.

The first step of GAAP is to process the measurements with dedicated tools to detect, classify, localize and track acoustic emissions. Under interest are the sound from cryogenic events (movement, crack of the ice pack, calving and drift of the iceberg), from meteorological forcing (wind, rain) and breaking waves, from marine fauna (from benthic organisms to marine mammals).

Then, the occurrence and parameters of these sounds are compared with environmental data coming from in situ measurements (sensor of movement of bivalves, visual observation of marine mammals, SAR image) and output of numerical models (waves and oceanic circulations) .
These comparisons allow for the understanding the structure of the arctic soundscape (why a sound exists? Who are the environmental drivers of this sound).

For field applications, GAAP is monitoring a piece (~5 kilometers long) of the frontier between open waters and ice (pack ice or glacier).
To achieve this goal, GAAP uses 2 small arrays of 4 hydrophones.

Two sites will be investigated by GAAP : the Lancaster strait (Canada) and the fjord of Yung Sund (North East of Greenland).

GIPSA Lab for underwater acoustics and signal processing, LEMAR for marine ecology and arctic experiments and TBM for GIS will be involved in GAAP Team.