Dear colleagues, Please note the extended abstract deadline for a session on polar soundscapes at POLAR2018: ‘The acoustic environment of the polar oceans: exploring polar soundscapes’ at the upcoming POLAR 2018, A SCAR & IASC Conference in Davos, Switzerland from 19-23 June, 2018. See http://www.polar2018.org/ The new deadline is: *12 November 2017, 6pm CET* The goal of POLAR2018 is to bring together excellent research from both poles, as well as from high altitude areas, focusing on the similar challenges those regions face. The program features 65 sessions, structured into 12 categories spanning topics from oceans and sea ice, cryosphere, atmosphere and climate, geology and geophysics to biology, ecology and more. Please consider submitting an abstract for the Polar Soundscape session outlined below. We hope to see you in Davos! Best Regards, Ilse Van Opzeeland (Alfred-Wegener Institute, Bremerhaven, Germany) Karolin Thomisch (Alfred-Wegener Institute, Bremerhaven, Germany) Sebastian Menze (Institute for Marine Research, Bergen, Norway) Denise Risch (Scottish Association for Marine Sciences, Oban, Scotland, UK) *Session Number OS-1 * *Session Title* The acoustic environment of the polar oceans: exploring polar soundscapes *Session Description* The underwater acoustic environment is created by the superposition of sounds from a multitude of sources of natural biotic and abiotic as well as anthropogenic origin. For aquatic life, marine mammals in particular, their perceived soundscape directly impacts their ability to hunt, communicate and possibly navigate these waters. However, for much of the world oceans, and for polar seas in particular, little is known about the diversity of contributions and the dial and seasonal patterns as well as long-term trends of the acoustic environment. This lack of knowledge hampers our ability to predict how anthropogenic change will impact on populations to which these waters form an essential habitat. The impact of anthropogenic activities on the acoustic environment may be direct, by adding noise, or indirect through global climate change, affecting acoustic propagation conditions and habitat usage. To outline the range of polar acoustic environments and the nature of their main contributories, this session aims at bringing together studies addressing these issues through in-situ recordings, methodological advances and numerical modeling.