Laurie Padman: S' O' GLOBEC P'I' Meeting,

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Southern Ocean GLOBEC Status of ADCP and
Microstructure

• L. Padman1, B. Beardsley2, S. Howard1
• 1 Earth Space Research, Seattle WA
• 2 Woods Hole Oceanographic Inst., Woods Hole MA

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ADCP Status
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ADCP Data Access
Data are served through ESRs web site as Matlab
MAT files http//www.esr.org/globec/globec.html a
nd through the U.S. GLOBEC Data System at
WHOI http//globec.whoi.edu/jg/dir/globec/soglobe
c/ where users can convert to ASCII, plot data,
etc.
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ADCP General comments

• Data loss occurs
• in heavy sea states and
• when vessels are underway in ice so, most winter
  data are just at sampling stations.
• Data include high-frequency signals (mainly tides
  and near-inertial), with magnitudes that can at
  times exceed the mean circulation.

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• CMiPS CTD-Mounted Microstructure Profiling
  System

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CMiPS Rationale

• Measures T(z) and C(z) at 1 cm resolution
  (oversamples at 512 Hz) to look at turbulence due
  to
• Shear instabilities
• Double diffusion
• Intrusions
• to answer the question What is the diffusivity
  in the pycnocline between the UCDW and the mixed
  layer?

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CMiPS Stations NBP0204
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West of Marguerite Bay (CTD-044)
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Marguerite Trough (CTD-091)
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Palmer LTER Amid Icebergs (CTD-113)
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Anchor Stations
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Anchor Stations
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Anchor Stations
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Comparison of T-S
Off-shelf Central WAP shelf SW of Palmer
Stn. Gerlache Strait
Low R?
Med. R?
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Summary

• Making progress on ADCP clean-up and archiving
  web-serving is now compatible with other GLOBEC
  programs.
• Microstructure profiling on NBP0202 and NBP0204.
  Tentative conclusion more mixing at main
  pycnocline than we thought from bulk
  parameterizations.
• But little evidence of mixing below 150 m except
  near the shelf break.
• No evidence of significant double diffusion in
  the GLOBEC area, but more likely in the Palmer
  LTER.