An adaptive grid to improve the efficiency and accuracy of modelling underwater noise from shipping.

Underwater noise pollution from shipping is a significant ecological concern. Acoustic propagation models are essential to predict noise levels and inform management activities to safeguard ecosystems. However, these models can be computationally expensive to execute. To increase computational efficiency, ships are spatially partitioned using grids but the cell size is often arbitrary. This work presents an adaptive grid where cell size varies with distance from the receiver to increase computational efficiency and accuracy. For a case study in the Celtic Sea, the adaptive grid represented a 2 to 5 fold increase in computational efficiency in August and December respectively, compared to a high resolution 1 km grid. A 5 km grid increased computational efficiency 5 fold again. However, over the first 25 km, the 5 km grid produced errors up to 13.8 dB compared to the 1 km grid, whereas, the adaptive grid generated errors of less than 0.5 dB.

[1]  S. Wasser,et al.  Evidence that ship noise increases stress in right whales , 2012, Proceedings of the Royal Society B: Biological Sciences.

[2]  Scott Veirs,et al.  Ship noise in an urban estuary extends to frequencies used for echolocation by endangered killer whales , 2015 .

[3]  K. Mackenzie.  Nine‐term equation for sound speed in the oceans , 1981 .

[4]  Sensitivity of Sea Surface Temperature Simulation by an Ocean Model to the Resolution of the Meteorological Forcing , 2013 .

[5]  Alexander O. MacGillivray,et al.  Mapping cumulative noise from shipping to inform marine spatial planning. , 2012, The Journal of the Acoustical Society of America.

[6]  Robert J. Urick,et al.  Principles of underwater sound , 1975 .

[7]  G. Frisk.  Noiseonomics: The relationship between ambient noise levels in the sea and global economic trends , 2012, Scientific Reports.

[8]  Michael A. Ainslie,et al.  Review of underwater acoustic propagation models. , 2014 .

[9]  Nathan D. Merchant,et al.  Underwater noise levels in UK waters , 2016, Scientific Reports.

[10]  R. Schusterman,et al.  Low-frequency amphibious hearing in pinnipeds: methods, measurements, noise, and ecology. , 1998, The Journal of the Acoustical Society of America.

[11]  E. Hamilton.  Geoacoustic modeling of the sea floor , 1980 .

[12]  D. Farmer,et al.  Zones of impact around icebreakers affecting beluga whales in the Beaufort Sea. , 2000, The Journal of the Acoustical Society of America.

[13]  Christopher W. Clark,et al.  Impacts of anthropogenic noise on marine life : publication patterns, new discoveries, and future directions in research and management , 2015 .

[14]  Xavier Lurton,et al.  An Introduction to Underwater Acoustics: Principles and Applications , 2010 .

[15]  S. Simpson,et al.  Size-dependent physiological responses of shore crabs to single and repeated playback of ship noise , 2013, Biology Letters.

[16]  Paul Etter.  Underwater Acoustic Modeling and Simulation, Fourth Edition , 2013 .

[17]  Werner Stefanie,et al.  Monitoring Guidance for Underwater Noise in European Seas- Part II: Monitoring Guidance Specifications , 2014 .

[18]  Jonathan Sharples,et al.  Introduction to the Physical and Biological Oceanography of Shelf Seas , 2012 .

[19]  J. Holt,et al.  An s coordinate density evolving model of the northwest European continental shelf: 1. Model description and density structure , 2001 .

[20]  A. Frankel,et al.  A New Context‐Based Approach to Assess Marine Mammal Behavioral Responses to Anthropogenic Sounds , 2012, Conservation biology : the journal of the Society for Conservation Biology.

[21]  C. Erbe.  UNDERWATER NOISE OF WHALE‐WATCHING BOATS AND POTENTIAL EFFECTS ON KILLER WHALES (ORCINUS ORCA), BASED ON AN ACOUSTIC IMPACT MODEL , 2002 .

[22]  C. Reichmuth,et al.  High-frequency hearing in seals and sea lions , 2016, Hearing Research.

[23]  R. Dunlop.  The effect of vessel noise on humpback whale, Megaptera novaeangliae, communication behaviour , 2016, Animal Behaviour.

[24]  The effect of sound speed profile on shallow water shipping sound maps. , 2016, The Journal of the Acoustical Society of America.

[25]  V. Popov,et al.  Hearing threshold shifts and recovery after noise exposure in beluga whales, Delphinapterus leucas , 2013, Journal of Experimental Biology.

[26]  F. Chen,et al.  The effect of ocean fronts on acoustic wave propagation in the Celtic Sea , 2014 .

[27]  S. Wales,et al.  An ensemble source spectra model for merchant ship-radiated noise. , 2002, The Journal of the Acoustical Society of America.

[28]  F. Chen,et al.  Shipping noise in a dynamic sea: a case study of grey seals in the Celtic Sea , 2020 .

[29]  Rex K. Andrew,et al.  An international quiet ocean experiment , 2011 .

[30]  Nathan D. Merchant,et al.  Evidence for ship noise impacts on humpback whale foraging behaviour , 2016, Biology Letters.

[31]  Dietrich Kurt Wittekind,et al.  A Simple Model for the Underwater Noise Source Level of Ships , 2014 .

[32]  R. Schusterman,et al.  In-air and underwater hearing sensitivity of a northern elephant seal (Mirounga angustirostris) , 1999 .

[33]  Timothy G. Leighton,et al.  Modeling vessel noise emissions through the accumulation and propagation of Automatic Identification System data , 2016 .

[34]  Changsheng Chen,et al.  An Unstructured Grid, Finite-Volume Coastal Ocean Model (FVCOM) System , 2006 .

[35]  B. McConnell,et al.  Sound exposure in harbour seals during the installation of an offshore wind farm: predictions of auditory damage , 2015 .

[36]  J. Hildebrand,et al.  Underwater radiated noise from modern commercial ships. , 2012, The Journal of the Acoustical Society of America.

[37]  C. Erbe,et al.  Identifying Modeled Ship Noise Hotspots for Marine Mammals of Canada's Pacific Region , 2014, PloS one.

[38]  Michael A Ainslie,et al.  A depth-dependent formula for shallow water propagation. , 2014, The Journal of the Acoustical Society of America.

[39]  Nathan D. Merchant,et al.  Underwater noise modelling for environmental impact assessment , 2016 .

[40]  Enrico Pirotta,et al.  Monitoring ship noise to assess the impact of coastal developments on marine mammals. , 2014, Marine pollution bulletin.

[41]  M. D. Collins.  A split‐step Padé solution for the parabolic equation method , 1993 .

[42]  Paul C. Etter,et al.  Underwater Acoustic Modeling and Simulation , 2018 .

[43]  W. Richardson.  Marine Mammals and Noise , 1995 .

[44]  Michael B. Porter,et al.  Computational Ocean Acoustics , 1994 .

[45]  R. Pingree.  Chapter 13 Physical Oceanography of the Celtic Sea and English Channel , 1980 .