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ioos / ioosngdac

IOOS National Glider Data Assembly Center (V2)
https://ioos.github.io/ioosngdac/
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Some deployments not including all of the `precise` location data #83

Closed kwilcox closed 9 years ago

kwilcox commented 9 years ago

Some deployments do not include precise_lat and precise_lon values for the majority of the timesteps. I'm assuming this is because the precise location isn't actually known when the glider is underwater. Example: sp030-20140813T1713 2015-09-02

Some deployments do include precise_lat and precise_lon values for each time-step. Were these interpolated? Is there an agreed upon method to backfill the deployments that did not include the interpolated positions in the DAC files? Example: UCSC294-20150430T2218

I see no reference to any of the precise variables in the documentation (https://github.com/ioos/ioosngdac/wiki/NGDAC-NetCDF-File-Format-Version-2). Should I not use these variables and stick to using only the post-processed profile data?

kerfoot commented 9 years ago

There's no documentation on it since we rename the lat and lon variables in the files submitted by the user to precise_lat and precise_lon (using ERDDAP). There is no general consensus on methods for interpolating these values from surface gps fixes. I don't think I can give you a good answer on this, other than to use latitude and longitude, which are estimated (mean) profile positions.