Oceans of noise - Whale and Dolphin Conservation Society

More documents

Recommendations

Info

Machinery noisePropulsion machinerye.g. engines, motors, gearsAuxiliary machinerye.g. generators, pumps,air conditioning units(1) Rotation(2) Repetitive discontinuities(3) Reciprocation(4) Turbulence(5) FrictionHydrodynamic noiseWind, Waves& Currents(1) Turbulence(2) Resonance(3) CavitationVibration(1) Cavitation(2) Resonant excitationof the hullPropellerPropeller noise(1) Rapid expansion & collapse(2) HammeringSeismic surveysPile drivingImpulsive noiseFigure 3.1. Sources and causes of underwater noise associated with the oil and gas industries3.4.1.1 Machinery noiseUnderwater machinery noise is the result of mechanical vibration that is coupled to the sea via,for example, a ship hull, oil platform legs or through the ground. Within the machinery noiseclass, a distinction between propulsion machinery (diesel engines, thrusters, main motors andreduction gears) and auxiliary machinery (generators, pumps and air-conditioning equipment) canbe made. Causes of machine vibration are:• Unbalanced rotating shafts• Repetitive discontinuities, e.g. gear teeth, armature slots or turbine blades• Reciprocating parts e.g. combustion in engine cylinders• Cavitation and turbulence in fluids flowing through pipes, pumps, valves, condensers• Mechanical friction3.4.1.2 Propeller noisePropeller noise is distinguished from machinery noise in that it is the result of propeller actionand originates on the surface of the propeller. As the propeller rotates through the water, regionsof low or negative pressure are created at its tips, if and when these negative pressures becomesufficiently strong, bubbles (cavities) begin to form. These bubbles are short lived and collapse ineither a turbulent stream or against the surface of the propeller. A sharp pulse of sound is31
produced as the bubble collapses and this process, “cavitation”, is responsible for the loud “hiss”often associated with ships. Causes of propeller noise are:• Cavitation• Propeller-induced vibration3.4.1.3 Hydrodynamic noiseThis type of noise is distinguished from propeller noise in that it does not originate at thepropeller but is caused by the flow of water past a physical structure such as the hull of a vessel orthe legs or risers of platforms. Causes of hydrodynamic noise are:• Vortex-induced vibration• Resonant excitation of cavities, plates, and appendages• Turbulent flow within pipes3.4.1.4 Impulsive noiseImpulsive sounds are those created by the rapid expansion and collapse of an air bubble (seismicair gun) or from the instantaneous application of pressure to a solid structure (pile driver).Impulsive sounds are typically short-lived and characterised by rapid rise times. Causes ofimpulsive noise are:• Explosions, for example during explosive wellhead decommissioning (decommissioning)• Airguns used during seismic surveys (exploration)• Pile drivers (installation)3.4.2 Rig and platform noiseRigs and platforms come in various forms, shapes and sizes and are found across a wide range ofdepths from coastal to oceanic waters. They fall into three general categories (1) man madeislands / caissons, (2) fixed platforms and (3) drill ships / semi-submersibles (Figure 3.2). Theirdesign, construction and local oceanographic conditions will affect both the path of the sound intothe water column and how much sound is transmitted (Figures 3.3 and 3.4).32
Page 2: Oceans of Noise 2004A WDCS Science
Page 8 and 9: In the US, the deployment of Low Fr
Page 10 and 11: its propagation beyond those declar
Page 12 and 13: The best evidence for noise being f
Page 14 and 15: Box 1. Characteristics of sound / l
Page 16 and 17: Sound speed (c)The speed (c) of a w
Page 18 and 19: Box 2. The effects of temperature,
Page 20 and 21: 2.1.2. Measuring sound intensityIde
Page 22 and 23: i.e. Equal pressure measurements di
Page 24 and 25: Spherical or Geometrical spreading
Page 28 and 29: 5.0 145Tug pulling loaded barge 1.0
Page 30 and 31: The source used during 3-D surveys
Page 34 and 35: Man-made islands /caissonsFixed pla
Page 36 and 37: 12 3245Drill bit6Figure 3.4. Sound
Page 38 and 39: Transientnoise sourcesAircraftHelic
Page 40 and 41: Results from the aerial surveys con
Page 42 and 43: haemorrhaging in the inner ears and
Page 44 and 45: However they also noted that whales
Page 46 and 47: 4. The Use of Sound by CetaceansChr
Page 48 and 49: seems logical, therefore, that if t
Page 50 and 51: However, despite the reported low a
Page 52 and 53: Kamminga and Wiersma 1981;Akamatsu
Page 54 and 55: SongSocial callsShrieksSlaps0.03-80
Page 56 and 57: anthropogenic factors that make the
Page 58 and 59: 5.3 Longer-term impactsNoise is cle
Page 60 and 61: 5.4 Indirect impactsThe above impac
Page 62 and 63: decompression sickness (DCS) as see
Page 64 and 65: 6. Examples of regional and nationa
Page 66 and 67: 6.3 ASCOBANS and ACCOBAMSTwo region
Page 68 and 69: implications and the discussion sho
Page 70 and 71: 7.1. Consideration of Voluntary vs.
Page 72 and 73: acoustic measurements have been mad
Page 74 and 75: 7.6. Methods of protectionComplianc
Page 76 and 77: 7.6.1 Monitoring7.6.1.1 Visual, aco
Page 78 and 79: Delory et al. (2002) use Ambient No
Page 80 and 81: 8. ReferencesAburto, A., Rountry, D
Page 82 and 83:
Caldwell, M.C., Caldwell, D.K., and
Page 84 and 85:
Engas, A., Lokkeborg, S., Ona, E. a
Page 86 and 87:
IWC 2002b. Report of the Scientific
Page 88 and 89:
McCauley, R.D. 1994. Seismic Survey
Page 90 and 91:
Potter, J. and Delory, E. 2001. Noi
Page 92 and 93:
Smolker, R.A., Mann, J. and Smuts,
Page 94 and 95:
Watkins, W.A. 1981b. The activities
Page 96 and 97:
ANNEX 1The Application of Marine Po
Page 98 and 99:
an important factor. 13 The judgeme
Page 100 and 101:
in the preparatory work of the LOSC
Page 102 and 103:
practice by the UNEP Governing Coun
Page 104 and 105:
protection and preservation of the
Page 106 and 107:
than international rules, standards
Page 108 and 109:
Four of the twelve regional seas tr
Page 110 and 111:
seismic operations in the Protocol
Page 112 and 113:
ConclusionAt the global level, only
Page 114 and 115:
Art 209 LOSC focuses on both standa
Page 116 and 117:
No State Party may impose condition
Page 118 and 119:
coastal States”. This formulation
Page 120 and 121:
If the IMO makes this determination
Page 122 and 123:
estrictions to vessels operating in
Page 124 and 125:
In the EEZ, in comparison to the te
Page 126 and 127:
Appendix A - Some international ins
Page 128 and 129:
Convention for the Protection of th
Page 130 and 131:
Available at:http://www.unep.ch/sea
Page 132 and 133:
BucharestConventionArticle XIPollut
Page 134 and 135:
environment1. The Contracting Parti
Page 136 and 137:
- that under Article III.8.c) of AC
Page 138 and 139:
e) no sudden or repeated change in
Page 140 and 141:
Ref: Nowacek et al. 2001.Location:
Page 142 and 143:
Location: Arctic• Vocal behaviour
Page 144 and 145:
• Vaquita surfacing duration and
Page 146 and 147:
• 6% of small delphinids (n=264;
Page 148 and 149:
Species type: Boto, Inia geoffrensi
Page 150 and 151:
• Humpback whales appeared tolera
Page 152 and 153:
• Behaviour interpreted as aggres
Page 154 and 155:
• There was no evidence of minke
Page 156 and 157:
• Northern right whales may be ap
Page 158 and 159:
• Migrating gray whales disturbed
Page 160 and 161:
to Ensenada De La Paz, Mexico. Aqua
Page 162 and 163:
distribution of humpback whales, Me
Page 164 and 165:
Richardson, C.R. Greene, C.I. Malme
Page 166 and 167:
Zhou, K., Pilleri, G. and Li, Y. 19
Page 168 and 169:
6. surveys for Cuvier’s beaked wh
show all

Oceans of noise - Whale and Dolphin Conservation Society

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?