[CF-metadata] FW: SeaDataNet and ADCP data

From: Lowry, Roy K. <rkl>
Date: Wed, 19 Mar 2014 16:18:01 +0000

Second attempt - first seems to have got stuck
________________________________________
From: Lowry, Roy K.
Sent: 18 March 2014 21:11
To: cf-metadata at cgd.ucar.edu
Cc: gilbert.maudire at ifremer.fr
Subject: SeaDataNet and ADCP data

Dear All (especially John Caron),

We're currently extending the SeaDataNet NetCDF standard - a profile of CF1.6 - to cover vessel-mounted ADCP and other profileTrajectory data (e.g. towed thermistor chains). Two issues have arisen.

1) For a ship, VMADCP have profiles of current parameters for each point on the trajectory. However, there are sometimes other single-depth parameters such as the seabed current easting and northing from bottom tracking. These could be carried as geophysical variables with a dimension (INSTANCE, TIME), but is it OK to mix these into a profileTrajectory file or would it be better to have two separate files, one with the 2D currents and one with the 3D? A similar issue arises with bottom temperature and sea level data returned by moored ADCPs. Any views?

2) We now have ADCPs fitted to AUVs. This means that the 'profile' z co-ordinates vary along the time dimension. On way around this might be to set the z co-ordinate of the profiles to be offset from the platform depth and then have the platform depth as a data value along the TIME dimension. Alternatively, we could add a TIME dimension to depth, which I'm guessing would be a new feature type.

Feedback/guidance on thsi would be much appreciated.

Cheers, Roy.

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Received on Wed Mar 19 2014 - 10:18:01 GMT