Mon 24 Apr 2006
In the midst of the ever-evolving database design process, I am starting to collect ADCP tidbits to better inform the future addition of this dataset to any site databases. The following notes are random and unorganized, but most will hopefully help advance the general understanding of these more complex data:
NOTE: The ADCP datatypes that will most concern us will be bottom-mounted, mooring-mounted (upward or downward looking), and shipboard. (other types would be ROV-mounted, instruments side-mounted on oil-rigs, etc) The following notes apply ONLY to shipboard ADCP data.
- Each ship has it’s own quirks, an understanding of which is needed to sucessfully process the data from each instrument.
New Horizon - instrument: Teledyne/RDInstruments Ocean Surveyor Broadband/Narrowband 150kHz ADCP
acquisition: PC with RDInstruments VmDas Version 1.42 software
- General: Teri Chereskin has been involved in all aspects of the CalCOFI ADCP data, from designing the instruement profiling scheme, to setting up the instrument pre-cruise, pulling data off of the collection computer post-cruise, transport, processing, any post-processing needed, and archiving. She maintains an independent ADCP database on her systems. I am trying to learn the ropes to take over some of those responsibilities for the CCE-LTER cruises. Teri’s webpage with documentation, ADCP data websites and other info is here:
http://tryfan.ucsd.edu/adcp/adcp.htm
- Data Size: The CalCOFI NH0604 cruise ADCP data is 2.9Gb, has 593 files and 5 different formats.
- Formats: .ENR - single ping raw data in beam coordinates (binary)
.ENS - serial info added at computer level (ie. with GPS brought in), beam coordinates with extra info (binary)
.ENX - in earth coordinates, calculated from internal header information (binary)
.N1R - GPS data (ascii)
.N2R - Ashtek data (ascii)
I believe that the ENS and ENX formats can be re-created by using the ENR and N1R, N2R files? I do not know the details yet of this nor of the CalCOFI final/reporting formats.
- Transport: Mark Ohman purchased a LaCie d2 Hard Drive Extreme for moving data from the ship to SIO. I originally formatted the drive for the PC in NTFS, but should possibly re-format to fat32? The NTFS format was readable on my Mac OSX, and was compatible with Teri’s system (type?). Teri has a disk on coast which can be directly connected with the external hard drive in the CCS server room.
more later…
One Response to “ADCP data for the LTER community”
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April 24th, 2006 at 4:21 pm
can i comment to myself?
my ‘insider’ at RDI sent me the following corrections (i should have asked him to blog them! next time…)
‘.ENS - this is simply the .ENR data that has been screened for good data/bad data purposes. No navigation data has been added to the file as of yet.
.ENX - this data is earth coordinate transformed and has navigation data infused with it from the .N1R and .N2R files.
.VMO - this is a file that provides the set up template if you wish to reprocess any data to produce the original (or new) .STA, .LTA, .ENS, or .ENX files.
Note, the raw files that must be kept in order to reproduce everything are as follows: .VMO, .ENR, .N1R, .N2R, .LOG (The log file isn’t super vital but it sure makes things easier when you’re looking back at data from long ago and trying to answer questions.
You are correct that ENS and ENX can be recreated with ENR, N1R, and N2R, but you need the .VMO too for the reconstruction to take place in VMDas rather than some home spun matlab file. ‘