ITHACA: thermistor time series

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ITHACA thermistor time series
DART-ITHACA Coordination Meeting, Zagreb, 30.11
01.12.2006.

• Hrvoje Mihanovic
• Hydrographic Institute of the Republic of
  Croatia, Split, Croatia
• www.hhi.hr

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The setting and data acquisition
BIEVO (dt10 min) 07.03 30.09.2006. SUAC
(dt10 min) 07.03 29.09.2006. LASTOVO (dt10
min) 07.03 27.09.2006. TCH2 (dt5 min) 17.08
11.09.2006.
Position of stations in the framework of ITHACA
project.
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The setting and data acquisition
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Comparison between TidbiT (Lastovo) and Aanderaa
(TCH2) measurements
dz-11 m for TCH2 11 equdistant sensors between
23 and 73 m (5-m vert. resolution)
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Comparison between TidbiT (Lastovo) and Aanderaa
(TCH2) measurements
Vertical profiles of sea temperature between 23
and 40 m (overlapping depths)
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Stationary spectral analysis
BIEVO
SUAC
LASTOVO
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Stationary spectral analysis
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Stationary spectral analysis
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Stationary spectral analysis
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Wavelet spectral analysis
Vertical profiles of normalized wavelet spectrum
at diurnal period
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Wavelet spectral analysis
Vertical profiles of normalized wavelet spectrum
at inertial period
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Wavelet spectral analysis
Normalized wavelet spectra at Bievo (4 m and 12
m)
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Wavelet spectral analysis
Time series and wavelet spectra at diurnal an
inertial period (Bievo, at the depth of 12 m)
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Wavelet spectral analysis
Normalized wavelet spectra at Suac (8 m and 24 m)
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Wavelet spectral analysis
Time series and wavelet spectra at diurnal an
inertial period (Suac, at the depth of 8 m)
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Wavelet spectral analysis
Normalized wavelet spectra at Lastovo (16 m and
24 m)
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Wavelet spectral analysis
Time series and wavelet spectra at diurnal an
inertial period (Lastovo, at the depth of 24 m)
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Wavelet spectral analysis
Stationary spectra at the depth of 28 m at
lastovo and TCH2(17 August 11 September 2006)
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Conclusions

• Succesful experiment with 29 of 30 thermistors
  recovered,
• Lastovo data compared with THC2 measurements,
• Diurnal oscillations intense at Lastovo (up to
  8C in the middle of July 2006 between 16 and 24
  m), but also present at certain depths at Bievo
  and Suac,
• Inertial oscillations at all three locations,
  especially strong at Lastovo (almost 9C at the
  beginning of August 2006 at 16 m),
• Other energy maxima also noted
• - semidiurnal at Bievo between 32 and 40 m,
  close to the surface at Suac (up to 12 m) and
  between 8 and 20 m at Lastovo
• - a noteworthy 10.2-h oscillation at Suac
  (36 and 40 m), and an 8-h oscillation between 8
  and 20 m at Lastovo,
• Wind influence appears to be very significant,
  separation between wind and tidal forcing needs
  to be done.