Winter/Spring 2006

Wireless real-time wave and current data in coastal ocean observing systems

Eric Siegel

Nortek USA

4:30 p.m., Thursday, January 12, 2006

Tidal Mixing Fronts and Polynyas in the Canadian Arctic

Charles Hannah

Bedford Institute of Oceanography

4:30 p.m., Thursday, January 19, 2006

Linking northwest Atlantic physical oceanographic processes to the oxygen regime of the Gulf of St. Lawrence

Denis Gilbert

Institut Maurice-Lamontagne
Mont-Joli, Quebec

4:30 p.m., Thursday, January 26, 2006

Solitary Internal Waves Impacting a Natural Slope

Ramzi Mirshak

Department of Oceanography
Dalhousie University

4:30 p.m., Thursday, February 2, 2006

Abstract: After giving an overview of solitary internal waves, I will present observations of a group of these waves encountering an island in the Saint Lawrence Estuary. A description of the wave group will be introduced, but attention will then focus on the fate of the lead wave as it encounters the island. Features not predicted by contemporary theory will be highlighted and discussed.

No seminar this week

Thursday, February 9, 2006

Wind-Forced Dynamics in Bonne Bay, Newfoundland

Clark Richards

Department of Oceanography
Dalhousie University

4:30 p.m., Thursday, February 16, 2006

Abstract: Ten Acoustic Doppler Current Profilers were deployed between September 2002 and September 2004 on the sill of the East Arm in Bonne Bay, a glacial fjord in Gros Morne National Park on the west coast of Newfoundland. The moorings were deployed to measure the velocity of water flowing over the sill, in order to better understand the exchange dynamics of the system. In addition to the current meter data, several cruises were conducted in June 2004 to collect hydrographic data in the Bay, specifically temperature, salinity and density profiles. Meteorological data from the area are also presented. Tidal flow over the sill is dominated by the M2 tide, with a vertical asymmetry between ebb and flood tides due to the superposition of the estuarine flow. Subtidal flow over the sill is two layer, and is primarily forced by the local wind stress. The development of a simple two layer numerical model supports this analysis, and with it some of the effects of spatially varying wind stress were examined. Topographic steering of the wind in the region was determined to be significant in accounting for the discrepancies between data and model results.

Winter Break - No Seminar

Thursday, February 23, 2006

Regional and global climate influences on North Atlantic hurricanes

Kerry Emanuel

Department of Earth, Atmospheric, and Planetary Sciences
Massachusetts Institute of Technology

4:30 p.m., Thursday, March 2, 2006
NOTE Room Change: LSC 4258, Psychology Bldg.

Abstract: Evidence is mounting that global tropical cyclone activity is responding to global climate change. In this talk, I will focus on North Atlantic hurricane activity and the regional and global oceanographic and atmospheric factors that contribute to its variability, with emphasis on the possible role of the so-called "Atlantic Multi-decadal Oscillation" (AMO) in controlling multi-decadal to centennial variability of hurricanes.

Optimized Biophysical Model for Icelandic Cod Larvae

Dave Brickman

Department of Fisheries and Oceans
Bedford Institute of Oceanography

4:30 p.m., Thursday, March 9, 2006

Abstract: During the last few years I have had the opportunity to participate in the Icelandic component of a multi-partner EU project concerned with cod meta-population structure in the North Atlantic. In this talk I will present an overview of the METACOD project and then focus on details pertaining to the biophysical modelling component that I was responsible for.

Adult and juvenile fisheries data will be presented to provide background to the Iceland setting. The circulation around Iceland is described using data and a high resolution model developed specifically for this purpose. New ideas on the origin of the Denmark Strait Overflow Water will be discussed. Biophysical models contain numerous poorly known parameters. I describe a new efficient formulation of a biophysical model that allows for optimal determination of these parameters by minimizing the mismatch between model predictions and data. Details of the numerical method will be presented, as well as model results.

Spectral Nudging of Coastal Models and Implications for Coastal Prediction
(or, Another Reason Not to Swim in Halifax Harbour)

Keith Thompson

Department of Oceanography
Dalhousie University

4:30 p.m., Thursday, March 16, 2006

Two Examples of 4Dvar Data Assimilation Application for Reanalysis and Short Range Forecast: Tsushima Strait and Bering Sea Circulations

G. Panteleev
(IARC, University of Alaska, Fairbanks)
D. Nechaev
(University of Southern Mississippi)

4:30 p.m., Thursday, March 23, 2006

Abstract: We present two sets of results of the variational data assimilation applied for the reanalysis and short-range forecast of the currents in the Korea/Tsushima Strait and the Bering Sea. The model used for the reanalysis is designed specifically for the efficient variational assimilation of the long-term observations in the ocean regions strongly governed by the flow through the open boundaries and by atmospheric fluxes. The experiments prove that this model can be also applied for the short-range forecast of the ocean currents. In both cases the preparation of the proper first guess solution is important. The data assimilation results demonstrate the ability of model to reproduce realistic seasonal variability of the circulation in the regions.

No seminar this week

Thursday, March 30, 2006

No seminar this week

Thursday, April 6, 2006

No seminar this week

Thursday, April 13, 2006

No seminar this week

Thursday, April 20, 2006

No seminar this week

Thursday, April 27, 2006

No seminar this week


Thursday, May 4, 2006

No seminar this week

Thursday, May 11, 2006

Evaluation of a Doppler sonar system for measurements of fish swimming velocity

Cristina Tollefsen

Memorial University of Newfoundland

4:30 p.m., Thursday, May 18, 2006

Abstract: Good measurements of fish swimming velocity would add another piece of valuable scientific information to the toolkit of the fisheries acoustician; however, previous investigations of Doppler sonar measurements of fish velocity have been relatively sparse, and no previous study has explored the possibilities available with newer coherent Doppler sonar systems. Comprehensive field and laboratory studies were undertaken to characterize the performance of a 250-kHz, 10-kHz bandwidth coherent Doppler sonar when applied to measurements of fish swimming velocity. In addition, a computer model of sonar operation was designed to assist in understanding experimental results and broaden the range of parameters investigated. The quality of velocity estimates was quantified by calculating the accuracy and precision in the Doppler velocity estimate for single solid targets. The effect of various sonar parameters and environmental conditions on Doppler velocity accuracy and precision was examined through four experiments with simulated fish targets, three experiments with live fish targets, and the computer model. Experimental and model results will be discussed, followed by implications for real-life fish velocity measurements.

Internal Solitary Waves in the Coastal Ocean and in Lakes

Kevin Lamb

University of Waterloo

4:30 p.m., Thursday, May 25, 2006

Abstract: Internal solitary waves are highly energetic events that are ubiquitous in coastal ocean regions. They effect acoustic propagation, resuspend sediments and in some locations significantly impact industrial activity. They can also be an important phenomenon in lakes. In this talk I will give an overview of internal solitary waves including aspects of their energetics, generation mechanisms in the ocean and in lakes, and dissipation mechanisms, including breaking of shoaling ISWs and shear instabilities.

Spatial calibration and application of a microstructure fluorometer

Fabian Wolk

Rockland Scientific International,
Victoria, BC

3:00 p.m., Friday, July 14, 2006

Location: Gordon Riley Conference Room, 3rd Floor, Oceanography Building