Shipping and ice-covered waters – how accurate are the MSFD “shipping bands”?

The EU Marine Strategy Framework Directive (MSFD) is an important tool in
sustainable use of the oceans, addressing the UN Sustainable Development Goal SDG-14 “Life below water” and contributing to the Blue Economy. The definition of “shipping bands” at third-octave bands centred on 63 Hz and 125 Hz has been particularly useful to assess the impacts of marine traffic in different regions around Europe and in other oceans. Shipping is bound to increase in Arctic regions, as the next years will see amplified effects of climate change and easier access to ice-covered waters, sometimes with the total disappearance of ice in summer. We present here a test case in the shallow waters of Cambridge Bay (Nunavut, Canada), using measurements made available by Ocean Networks Canada and the Canadian Ice Service. We compare the months of August (little to no ice, and shipping activity) with the months of May (generally full ice cover and
dynamic ice processes, but no shipping), between 2015 and 2020. Sound Pressure Levels and other metrics were derived with PAMGuide (Merchant et al., 2015, 2022), focusing on the “shipping bands”. Individual ship signatures and general human impacts can be clearly identified and overall trends are compared with AIS data. As ice cover increases and shipping stops, the ”shipping bands” are dominated by a variety of ice processes, and the comparisons between years shows interesting implications for the use of the MSFD in ice-covered waters. Monitoring of these bands also has direct implications for local communities and the fragile ecosystems present in Arctic waters.