Oceanographic Pre-Analysis: High Density Oceanographic Sampling Campaigns in Support of Hydrography

Jonathan Beaudoin
Research Scientist

CCOM/JHC University of New Hampshire

Friday, Feb. 11, 2011, 3:00pm

One of the remaining challenges in multibeam echosounding is adequately correcting for the effects of refraction of the acoustic ray path between the echosounder and the seafloor. Even with state-of-the-art equipment, technology and algorithms, having a poor understanding of the variability of the water mass properties that control the speed of sound can detract from the quality and accuracy of even the best planned survey. There are clear benefits to being able to identify challenging environments and assess the impact of water mass variability on sounding uncertainty during the survey planning stage. Knowing of challenges before hand allows for proper planning, potentially giving field parties more options to deal with challenging conditions.

The first step to performing such an assessment is to acquire data that can be used to characterize the nature of oceanographic variability in an area of interest.  In this talk, we explore the idea of performing oceanographic reconnaissance campaigns using underway vertical profiling equipment such as Moving Vessel Profilers (MVP), Underway Conductivity-Temperature-Depth systems (UCTD) and Underway Sound Velocity systems (USV). Using underway sampling technology allows for rich and dense data sets that can be used to understand the driving forces behind water mass variability. Data alone, however, does not fuel informed decision making, thus we also examine analytical tools that enable the hydrographic surveyor to ascertain the impact of water mass variability. The combination of sampling methods, hardware technology and software tools has the potential to change the way that hydrographers approach challenging refraction environments. Data sets collected in various estuarine environments will be examined and upcoming field campaigns in Portsmouth Harbor will be discussed.


Jonathan Beaudoin has a PhD (2010) in Geodesy and Geomatics Engineering from the University of New Brunswick and Bachelor's degrees in Geodesy and Geomatics Engineering (2002) and Computer Science (2002), also from UNB.  Having just arrived at CCOM in the Spring of 2010, he plans to carry on in the field of his PhD research, that of estimating sounding uncertainty from measurements of water mass variability.  His research plans include an examination of oceanographic databases such as the World Ocean Atlas and the World Ocean Database to see how the data contained in these comprehensive collections can be turned into information that is meaningful to a hydrographic surveyor.  Other plans involve assessing how to best acquire, visualize, process and analyze data from high-resolution underway sound speed sampling systems, again, in terms that are meaningful to a hydrographic surveyor.  Jonathan will also be helping out with the Geocoder project, bringing his experience in processing and normalization of  backscatter measurements from Kongsberg and Reson multibeam echosounder systems.