Seasonal and Interannual Variations in Hydrographic
Distributions in Marguerite Bay and Environs

Outline of Presentation
Show thermohaline properties from 2002 cruises
Describe circulation from 2002 cruises
Compare 2002 patterns with those from 2001 cruises
Preliminary estimates of exchange
Summary of circulation characteristics

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Change in Heat Content
For 2001 cruises heat content in upper waters was negative and in deeper waters was positive
Indicates a net heat loss from surface
Heat source in bottom waters CDW
Difference between two cruises was negative over
entire water column (-0.000342 J/m3/day) - mostly from surface cooling
Little difference in bottom water heat content between two cruises suggests continual input of warm water

Summary
Multiple pathways for CDW to get onto shelf at depth
See effect of warm deep water in surface
Appears to be gyre circulation in northern part of study region
Inshore coastal current seen in 2001 not as apparent in 2002

Future Work
Calculate heat change from all cruises
Calculate volume change of warm and cool water between cruises flushing rates/turnover times for shelf
Heating/cooling differences over the study area may show regions of polynya formation
Calculate the contribution of Lower CDW to warm water on shelf
Topographic mixing effects on breaching of Winter Water layer