Science of Sound
What is sound?
How do you characterize sounds?
How are sounds made?
What happens when sound pressures are large?
How fast does sound travel?
Why does sound get weaker as it travels?
How does sound move?
How does sound travel long distances? The SOFAR Channel
History of the SOFAR Channel
Sound Speed Minimum
Sound Travel in the SOFAR Channel
Sound Channel Variability
How is sound measured?
What units are used to measure sound?
How are sounds viewed and analyzed?
How is hearing measured?
What sounds can we hear?
What sounds can animals hear?
Sounds in the Sea
What are common underwater sounds?
How does sound in air differ from sound in water?
How do people and animals use sound in the sea?
Why do sounds have certain properties?
How will ocean acidification affect ocean sound levels?
How does marine life affect ocean sound levels?
How does shipping affect ocean sound levels?
What is intensity?
Introduction to Decibels
Introduction to Signal Levels
Sound Pressure Levels and Sound Exposure Levels
Frequency Weighting of Signal Levels
Introduction to Phase
Ocean Noise Variability and Noise Budgets
Cylindrical vs. Spherical Spreading
Propagation from a sound source array in the near field and far field
Wave Front Propagation
How does sound travel in shallow water?
Sonar Equation Example: Active Sonar
Sonar Equation Example: Passive Sonar
Detection Threshold for Sonar
False Positives and False Negatives
Statistical vs. Biological Significance
Science of Sound Summary
Animals and Sound
Importance of Sound
Why is sound important to marine animals?
Use of Sound
How do marine animals use sound?
Marine Mammal Communication
Vocalizations Associated with Reproduction
Sounds Associated with Aggression
Marine fish communication
Marine invertebrate communication
Marine mammals feeding
Marine fish and invertebrates feeding
Marine mammal navigation
How do marine mammals produce sounds?
How do fish produce sounds?
How do marine invertebrates produce sounds?
How do marine mammals hear?
Hearing in Land Mammals
Hearing in Pinnipeds, the Amphibious Ear
Hearing in Cetaceans and Sirenians, the Fully Aquatic Ear
How do sea turtles hear?
How do fish hear?
How do marine invertebrates detect sounds?
Effects of Sound
Determine if a sound affects a marine animal
Potential effects of sound on marine mammals
Behavioral Changes in Mammals
Masking in Mammals
Hearing Loss in Mammals
Potential effects of sound on marine fishes
Behavioral Changes in Fishes
Masking in Fishes
Hearing Loss in Fishes
Measure marine mammal’s reaction to sound
Hearing Sensitivity Studies
Controlled Exposure Experiments
Moderate or eliminate the effects of human activities
Anthropogenic Sound Sources
What components of sound are used for hearing?
How did odontocete hearing evolve?
Animals and Sound Summary
People and Sound
How is sound used to navigate underwater?
How is sound used to measure water depth?
How is sound used to find objects on the ocean bottom?
How is sound used to locate fish?
How is sound used to identify fish?
How is sound used to communicate underwater?
How is sounds used to transmit data underwater?
Research Ocean Physics
How is sound used to measure temperature in the ocean?
How is sound used to measure global climate change?
How is sound used to measure currents in the ocean?
How is sound used to measure waves in the surf zone?
How is sound used to measure the upper ocean?
How is sound used to help make long-term measurements of the ocean?
Examine the Earth
How is sound used to study the Earth’s history?
How is sound used to explore for oil and gas?
How is sound used to measure, detect, and track oil?
How is sound used to study undersea earthquakes?
How is sound used to study underwater volcanoes?
How is sound used to research wind energy?
Investigate Marine Animals
How is sound used to study marine mammal distribution?
How is sound used to estimate marine mammal abundance?
How is sound used to protect marine mammals?
How is sound used to study the distribution of marine fishes?
How is sound used to measure plankton?
How is sound used to study coral reefs?
How is sound used to identify ecological hotspots?
How is sound used to measure rainfall over the ocean?
How is sound used to measure wind over the ocean?
How is sound used to find submarines?
How is sound used to monitor nuclear testing?
How is sound used to monitor and defend harbors?
History of Underwater Acoustics
The Early 1900s
World War I: 1914-1918
The 1920s and 1930s
World War II: 1941-1945
The Cold War
Advanced Topics in People
People and Sound Summary
For Decision Makers
Webinar Archive: Science of Sound
Webinar Archive: Marine Animal Sound Production and Reception
Webinar Archive: Potential Effects of Sound on Marine Mammals
Webinar Archive: Potential Effects of Sound on Fishes
Webinar Archive: Summary and Questions
Science of Sound Video
Marine Mammal Hearing Video
Hearing in Marine Fishes
Ecological Risk Assessment Video
Decision Maker Tutorials
Decision Makers Effects of Sound Tutorial Introduction
Tutorial: Mammals – Behavior Changes
Tutoria:l Mammals – Masking
Tutorial: Mammals – Hearing loss
Tutorial: Mammals – Strandings
Tutorial: Fishes – Behavioral Change
Tutorial: Fishes – Masking
Tutorial: Fishes – Hearing Loss
Tutorial: Fishes – Physiological Stress
Determine if a Sound Affects a Marine Animal Tutorial Introduction
Tutorial: Sound Levels at Distance and Depth
Tutorial: Where are marine animals likely to be located relative to the source?
Tutorial: Sound Level Exposure
Tutorial: Can Animals Sense These Sounds Part I
Tutorial Can Animals Sense These Sounds Part II
Reference List: Animals and Sound
Units Page for Regulators
North Atlantic Right Whale
Amazon River Dolphin, Boto
Baiji, Yangtze River Dolphin
Beluga Whale, White Whale
False Killer Whale
Killer Whale, Orca
California Sea Lion
Hawaiian Monk Seal
Northern Fur Seal
Sea Urchin (Kina)
Hardhead Sea Catfish
Other Natural Sounds
Submarine Volcanic Eruptions
Waves on Beach
Explosive Sound Sources
Ocean Acoustic Tomography Transmission
Personal Water Craft (PWC)
SURTASS LFA Sonar
Underwater Breathing Apparatus
Audio Gallery Summary
Explosive Sound Sources Technology
Projector (sound source)
Observing the Sea Floor
Side Scan Sonar
Observing Ocean Currents and Temperature
Acoustic Current Meters
ADCP (Acoustic Doppler Current Profiler)
Acoustic Tomographic Mooring
Acoustic Rain Gauge (ARG)
WOTAN: “Wind Observations Through Ambient Noise”
Observing and Monitoring Marine Animals
Acoustic Fish Tags
Fish Finding Sonar
Acoustic Datalogging Systems
Archival Marine Acoustic Recording Units (ARUs)
Real-time Passive Acoustic Sensors
Passive Acoustic Recording Tags
Locating Objects by Listening to their Sounds
Sound Surveillance System (SOSUS)
Locating objects using sonar
SURTASS LFA Sonar Technology
Forward Looking Sonar
Technology Gallery Summary
For Decision Makers
Science of Sound Tutorial: Introduction
Tutorial: What is Sound?
Tutorial: Intensity or Loudness
Tutorial: Frequency or Pitch
Tutorial: Speed of Sound
Tutorial: Sound Spreading
Tutorial: Sound Channel
Effects Tutorial Introduction
Effects Tutorial Overview
Tutorial: Behavioral Changes
Tutorial: Hearing Loss
Tutorial: Physiological Stress
Tutorial: How do you determine if a sound affects a marine animal?
Tutorial: How can we moderate or eliminate the effects of human activities?
Technology Tutorial Introduction
Tutorial: Projector (Sound Source)
Tutorial: Measure Water Depth
Tutorial: Find Objects on the Sea Floor
Tutorial: Find Fish
Tutorial: Communicate Underwater
Tutorial: Measure Temperature
Tutorial: Measure Currents
Tutorial: Study the Sea Floor
Facts and Myths
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