Questions on Data

• QUESTION: [ Data Disclaimers | Data Naming | Data Formats | Data Navigation ]
• Answer: Data Expectations

• QUESTION: Where do I find data availability status?
• Answer: File Status Check

Questions on Argo GDAC

• QUESTION: Where is the information on Argo?
  
• Answer: USGODAE Argo Page

• QUESTION: If I want to compare salinity values collected from other measurement
  devices to the Argo float devices, by date, should I look at JULD (or
  JULD_LOCATION?) values that were recorded 10-14 days ahead of the
  other measurement device (since they drift for 10-14 days)?
  For example, suppose I have salinity values recorded from a device on
  1/14/09 near Virginia and I want to compare those values to Argo
  floats that were also located near Virginia on that day. Should I look
  at Argo floats whose JULD values are 1/4/09? or 1/14/09?
• Answer: JULD is the time that the profile observation was taken.  After the 10
  days drift phase, the float takes the profile measurement during
  ascent phase.  Once at the surface, it reports the time it reached the
  surface and the profile measurement.  So, you want to match the Argo
  time as closely as you can with the time of the other measurements.
  
  
• QUESTION: How are Argo float data validated? Are all the data in the Argo netCDF files already validated? Also, I was under the impression that this site would have the same Argo float data as the coriolis site (http(cl)//www.coriolis.eu.org/cdc/dataselection/cdcDataSelection.asp). However, I noticed that the coriolis site has Argo floats displayed on their map for 4/13/09 to 4/20/09 at these coordinates(cl) 41.02 N,26.27 N, 85.12 W, 56.32 W, but this site does not. Why is that?
  
• Answer: The Argo data undergo a series of real-time tests before the data are
  distributed.  These are a series of quick tests designed to identify
  and flag values that are "obviously bad"; such things as bad
  observation date or location, physically impossible values,
  unrealistic gradients, etc.  The profiles with DATA_MODE = "R" or "A"
  and file names R<float_id>_<cycle>.nc have undergone only these tests.
  Additional scientific quality control tests are applied in
  delayed-mode - 6 months to 1 year after observation.  In addition to
  more thorough visual screening by an oceanographer, an objective
  analysis technique is applied to identify and correct salinity sensor
  drift.  The profiles with DATA_MODE = "D" and file names
  D<float_id>_<cycle>.nc have undergone these additional tests.
  All of these QC procedures are documented in
  http://www.coriolis.eu.org//cdc/argo/argo-quality-control-manual.pdf
  The two GDACs will generally have the same datasets.  The US GDAC is
  currently experiencing an problem with data delivery from the
  individual data providers and is receiving all of its data through
  synchronization with the French GDAC.  This introduces a 24 hour delay
  in the receipt of data at the US GDAC.  We hope to have this fixed
  very soon.  Based on your message, I will double check to be sure this
  is functioning normally.