Wednesday, June 22, 2016

Databases Galore - 14

Fig. 1 WOD-13 Zones
The new database I am in the process of using (Fig. 1) is arranged kinda like the Dredd Blog zones concept (Zone In On Sea Level Change)

It is the World Ocean Database (ver. 13), called "WOD-13" for short.

One can select a zone, the download the data.

Then what?

I have written a C++ program that is working after many problems.

I used only their documentation to traverse the jungle of numbers and letters, since I know of no C++ programs for doing the processing.

The 'C' and 'Fortran' sample programs are next to no help for an object oriented approach.

Here is a sample "cast" (similar to one PSMSL station record) :
C41303567064US5112031934 8 744210374426193562-17227140 6110101201013011182205814
01118220291601118220291901024721 8STOCS85A3 41032151032165-500632175-50023218273
(WOD-13 Manual, p. 128). That cast has 1303 individual data elements (bytes) which must be painstakingly and flawlessly put together into useful information, such as:
Cast type: C
Profile length: 1303
Unique Cast #: 67064
Cruise: 11203
Year: 1934
Mon:  8
Day:  7
Time: 10.37
Lat: 61.93
Lon: -172.27
Levels (Depths): 4
Profile Type: 0
Variable Count: 6
Notice that latitude and longitude are included, so I can synchronize this data with Dredd Blog zones.

We will then have a comprehensive graphing system for both above-the-surface (PSMSL) and below-the-surface (WOD-13) information for our contemplation.

One file I downloaded and used for testing (WOD zone 7015) has over 3,600 casts in it, and is 6 megabytes in size (ARGO float profile data type).

I wrote the program to process every WOD file in a particular directory, so I download a bunch and off we go.

I want to concentrate on Dredd Blog zones I have already graphed out with PSMSL data, and compare above and below surface factors to derive more understanding.

A one-stop lab eh?

I now plan to redirect the data into "csv" files, and or SQL tables, for future use.


Will post more soon.

The next post in this series is here, the previous post in this series is here.


  1. Thanks Dredd!
    Mucho trabajo hombre!

    Looking forward to the 'lecture' on this.

    Meanwhile, was hunting around for more detail on the contributing factors (there are many) to glacial and ice sheet 'calving' thinking there might be a relationship to sea levels (eustasy)and found this paper from '07.

    There's buoyancy forces, gravitational forces, land forces, water and air temps, tensile, sliding and tearing crack propagation and a whole lot more to the story than can be gleaned from first glances.

    As you have previously taught, the primary influence on the calving around the Antarctic is surface melting where downward penetration through surface crevasses have no limit. The interesting feature of all calving is that a hierarchy of contributors work patiently and unhurriedly together and ultimately lead (with a certain panache that requires no audience; but rewarding to those who happen to be around)to the actual 'event'. The more I learn about SLC, the more interested I become in what happens to the ice.

  2. Dredd Blog teaches that most surface melt, by far, takes place on the Greenland Ice Sheet.

    Most Antarctic melt takes place under the surface at about 400 meters where the warmer water is.

  3. Interesting read on what do wrt the world's biggest naval yard in Norfolk VA and rising seas. Part of "The Ground Truth Project"