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Application of corrections to original XBT data  
Note: The procedure is essentially like in Gouretski and Reseghetti, 2010, but with a timevariable depth correction factor.
 
1) All XBT sample depths are recomputed (if nesessary) according to the SIPPICAN FRE 2) XBT observed temperature is corrected for thermal bias according to the time (year) of the observation (see thermal_bias correction files)
thermal_bias_t4t6_vs_year.dat Tcorrected = Tobserved  Thermal_Bias
3) Depth correction factor ("stretching") is calculated using the following formula
(as in Gouretski and Reseghetti, 2010, but with different numerical values of the coefficients).
4) This "nominal" depthdepending stretching factor is further modified depending on the deviation of the XBTprofile
mean temperature (tmean_profile) from the "nominal" mean temperature (tmean_nominal). (Values of tmean_nominal are given in
mean_temperature files).
Here mean temperature refers to the mean temperature within the respective layer between the ocean surface and the sample depth (Z)
for which the correction is calculated.
5) "Observed" (Sippican) XBT sample depth is now finally corrected: V. Gouretski, 31 May 2010, KlimaCampus, Hamburg 
Last modified: Fri, 4Jun2010 20:25 UTC  NODC.Webmaster@noaa.gov  
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