LADCP WWW

Lowered Acoustic Doppler Current Profiler Software

Martin Visbeck has coded a MATLAB based software package that allows to process LADCP and LADCP-2 data. This is the first version released to the public and I am eager for comments.

• Get a zip compressed file containg all m-files.
• Get a tar file containg all m-files.
• Get a tar -z compressed file containg all m-files.
• Get a tar -z compressed file containg a LADCP-2 sample station.
• Get a directory list containg all-files.

How to process the LADCP data using the MATLAB software

You will need the RDI BB/WH ADCP raw data and MATLAB. If you want absolute velocities you have to know the start and end postion of the cast. You can also use an external profile of soundspeed and load Juergen Fischer .par paraemter file.

* means this step is essential, + means this step is not essential, - means an alternative to the one before.

• + 'ladcpmenu' is the main m-file that allows you to click your way thorugh an LADCP-2 processing scheme.
• * 1) click on button [1] or set 'cop=1' and 'adcpload'. If you have specified 'file=['filename'];' it will try to open the specified name.
• + click on button [2] to get some extra information
• + Juergen Fischers parameter files can be loaded now by 'getpar'
• * 2) click on botton [3] or set 'cop=3' and 'adcpload' to load all the relevant data into memory (This is the slowest part!)
• + click on button [6] or set 'cop=6' and 'adcpload' to convert beam to earth coordinates.
• * 3) click on button [7] or call 'getupdown' to move some arrays and set dummy up/down cast. (This is also essential for just one instrument!)
• + repeat all the above steps after clicking button [5] in order to load the second data set (LADCP-2) systems only. Note at this point we assume synchronized data....
• + if you have a soundspeed profile load it now 'getsound'
• * 4) click on button [8] or call 'getdepth' to merge arrays, apply compass deiation, remove large tilt data, remove data with large error velocity, find depth of cast, look for surface, look for bottom, correct velocities for soundspeed, get binlength matrix .....
• * 5) click on button [9] or call 'getshear' to compute shear arrays, mean shear profiles, and mean relative velocity profile for up+down cast, and up/down cats alone.
• - call 'getshear2' to use std editing instead of median.... seems to work better in some cases, need more investigation!
• + call 'loadpos' or set arrays 'poss=[ phid phim lamd lamm];' and 'pose=[ phid phim lamd lamm];'
• * 6) click on button [10] or call 'getabs' to find barotropic correction.
• + check the other buttons for some plotting options....