Acoustic observations of the ocean interior: Stories of gas bubbles

Tom Weber

Center for Coastal and Ocean Mapping

University of New Hampshire

Wednesday, March 1, 2017
Pacific Forum—11:00 a.m.

Gas bubbles are ubiquitous in the ocean and play an important role in several ocean processes. Gas bubbles formed by breaking wind waves play a role in the transfer of gas and momentum across the air-sea boundary. Methane gas formed by both biogenic and thermogenic processes is transported via bubbles into the water column and sometimes to the atmosphere. Gas bubbles also provide a mechanical advantage to several marine organisms including siphonophores and fishes with swim bladders. The large impedance contrast between the gas inside of the bubble and the surrounding water makes them easy to observe using acoustic waves—especially when the acoustic system operates near a bubble’s resonance frequency. In this talk I will describe the use of multibeam, split-beam, and broadband echo sounders for detecting gas bubbles in the ocean and, once having detected them, for understanding their story (i.e., their evolution and ultimate fate).

Print Version (PDF)

Next: March 15, Jonathan White

Products

Data repository
Data policy
What is happening in Monterey Bay today?
Central and Northern California Ocean Observing System
Chemical data
Ocean float data
Slough data
Mooring ISUS measurements
Southern Ocean Data
Mooring data
M1 Mooring Summary Data
M1 ADCP (CeNCOOS)
M1 Asimet
M1 Download Info
M1 EMeter
M1 Fluorometer (CeNCOOS)
M1 GPS Location
Molecular and genomics data
ESP Web Portal
Seafloor mapping
Upper ocean data
Spatial Temporal Oceanographic Query System (STOQS) Data
Image gallery
Video library
Seminars
Previous seminars
David Packard Distinguished Lecturers
Research software
Video Annotation and Reference System
System Overview
Knowledgebase
Annotation Interface
Video Tape User Guide
Video File User Guide
Annotation Glossary
Query Interface
Basic User Guide
Advanced User Guide
Results
Query Glossary
FAQ
VARS Publications
Oceanographic Decision Support System
MB-System seafloor mapping software
MB-System Documentation
MB-System Announcements
MB-System Announcements (Archive)
How to Download and Install MB-System
MB-System Discussion Lists
MB-System FAQ
Matlab scripts: Linear regressions
Introduction to Model I and Model II linear regressions
A brief history of Model II regression analysis
Index of downloadable files
Summary of modifications
Regression rules of thumb
Results for Model I and Model II regressions
Graphs of the Model I and Model II regressions
Which regression: Model I or Model II?
Matlab scripts: Oceanographic calculations
Matlab scripts: Sound velocity
Visual Basic for Excel: Oceanographic calculations
Educational resources
MBARI Summer Internship Program
2017 Summer Interns Blog
Education and Research: Testing Hypotheses (EARTH)
EARTH workshops
2016—New Brunswick, NJ
2015—Newport, Oregon
2016 Satellite workshop—Pensacola, FL
2016 Satellite workshop—Beaufort, NC
EARTH resources
EARTH lesson plans
Lesson plans—published
Lesson plans—development
Lesson drafts—2015
Lesson drafts—2016 Pensacola
Center for Microbial Oceanography: Research and Education (C-MORE) Science Kits
Publications
Sample archive