Suchergebnisse

Impacts of man-made acoustic noise on the marine environment are associated to the frequency and timing of any activity as well as the distribution and abundance of marine life. Offshore commercial operations, shipping activities, energy exploration and pile driving add noise to the already established ambient noise levels. Attention has been raised by the years to the topic of underwater noise and its effects on marine life, but the effects of underwater noise are not yet fully understood. As the adoption of the European Marine Directive (MSFD 2008/56/EC - Descriptor 11) has given great impulse to the research in this field, governments, companies and institutes are working to specify the background ambient noise levels. Those studies have formed the guidelines and have set the protocols for performing safer offshore operations, which are adopted by the major energy companies. Hellenic Petroleum S.A. has undertaken a Marine Seismic Survey in West Patraikos Gulf waters in Greece between January and February 2016, which was coupled with an intensive sound noise monitoring program. Acoustic data were collected around Marine Protected Areas of the Inner Ionian Archipelago during three monitoring phases: 1) the pre-start, 2) the concurrent and 3) the post-completion ones. Sound pressure levels (SPLs) were collected using drifting hydrophones deployed on a frequent schedule, spanning 1.5 months, collecting more than 130 hours of data. The ambient noise data gave insight into the footprints of the anthropogenic and biogenic factors on the soundscape of the Inner Ionian Archipelago. Most importantly, the recorded SPLs of the impulsive seismic and the continuous shipping noises were studied against the bearing and distance to the corresponding sound sources.

High-latitude regions like the Arctic Ocean are becoming increasingly important as global warming makes them more accessible, raising economic and political interests. Sea ice reduction is facilitating resource exploration, marine transport and other activities. Warming waters and changing sea ice conditions lead to shifts in ecosystems. Resource exploitation will grow in the coming decades, offering new opportunities but also new challenges to these fragile environments and their biodiversity. The natural and anthropogenic changes in this region will change the characteristics of soundscapes. To measure and assess them at a variety of spatial and temporal scales, the International Quiet Ocean Experiment created in 2017 a working group on Arctic Acoustic Environments. First activities focus on synthesising state-of-the-art knowledge of Arctic sounds—past, present and future. WG activities were presented at the Arctic Observing Summit 2018 and its recommendations adopted at the 2nd Arctic Science Ministerial. We are linking with indigenous communities and other stakeholders to address emerging trends, plan where/when to conduct optimal acoustic surveys, and prioritise metrics. We present the plans and first actions of this IQOE WG.