[Seavox] A question of principle on instruments

[Giuseppe M. R. Manzella]

Dear Roy,

unfortunately there are many questions related to the use of XBTs.
For sure it is important to specify the type (T4, T6, Deep Blue or 
other).
Not all are using the same fall equation for the calculation of the 
depth, and there is a wide variety of coefficients of the fall rate 
equation used even for the same type.

For a general review of accuary problems related to instruments I 
suggest this paper 
http://onlinelibrary.wiley.com/doi/10.1002/rog.20022/pdf
For the problems related to XBT this is another paper: Gouretski, V. 
and F. Reseghetti, 2010, On depth and temperature biases in 
bathythermograph data: Development of a new correction scheme based on 
analysis of a global ocean database. Deep-Sea Research I, Vol. 57(6), 
pp. 812-834, doi:10.1016/j.dsr.2010.03.011, Gouretski, Reseghetti 
depth and temperature corrections, updated corrections.


I personally would not use Sippical Fall rate or IGOOS fall rate, but 
provide the value of coefficients.

Ciao

Giuseppe


il Fri, 8 Nov 2013 15:38:37 +0000
  "Lowry, Roy K." <rkl at bodc.ac.uk> ha scritto:
> Dear All,
> 
> An issue is arising with a request to add a set of additional XBT 
>entries to the SeaVoX instrument vocabulary (L22).  In most cases, 
>this includes two entries for certain physical types of XBT (e.g. 
>Sippican T5) with the entries differentiated by the fall-rate 
>equation applied (Sippican or GOOS). I'm a little uneasy about this 
>as to me it could be viewed as shoe-horning information that isn't 
>actually instrument type into the instrument description. However, I 
>am also aware of instruments that have multiple designations and all 
>that's different between the variants is the firmware.
> 
> Anybody else have any views on this?
> 
> Cheers, Roy.
> 
> Please note that I now work part-time from Tuesday to Thursday. 
> E-mail response on other days is possible but not guaranteed!
> 
> 
> 
> 
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\\
>   >    Giuseppe M.R. Manzella
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