CalCOFI 0707NH CTD Data Processing Notes

Seabird 911+ CTD with Deck Unit v1 requires AlignCTD of secondary conductivity
sensor by 0.73sec. This has been applied along with a 4sec oxygen sensor offset.
V0 - Transmissometer
V1 - Seapoint Fluorometer
V2 - ISUS v2 Nitrate sensor, user-polynomial
V3 - open
V4 - SBE43 O2 sensor
V5 - open
V6 - Altimeter
V7 - PAR
V15 - Surface PAR

Please note there is only one oxygen sensor deployed in 2007. Secondary sensor
plots will only have O2 bottle data, no secondary O2 profiles.

There were some issues with the ISUS this cruise. It turns out the light pipe had 
become loose which caused a different relationship with nitrate. So this cruise
had three (essentially two) regressions - Cast 001-012 & Cast 047-073, although
processed in two bins with slightly different regressions, were essentially the
same; Cast 013-046 had a loose ISUS light pipe which was discovered then tighten
for cast 047. See the ISUSVvsNO3 regression plot for specific coefficients.
The sta-corrected estimated ISUS nitrate would not be affected since the relationship
is dynamically calculated for each cast.
Other issues with the ISUS were primarily the battery providing enough voltage.
Batteries were swapped after 3 casts and sometimes did not power the ISUS for the
entire cast or at all. CTD operators may have forgotten to plug in the battery as well.

Cast 068 hdr Line & Station were misentered as 76.780.0 and corrected to 76.7 80.0.

No data codes have been entered into this cruise. Primarily, the ISUS sensor voltage 2
would be the main recipient of data quality codes of 8 or 9. I hope to get back to
this, time-permitting.

JRW 10/09/2018
