INITIAL WORLD OCEAN DATABASE COLLECTION OTGA – UEM TRAINING COURSE – FUNDAMENTALS OF OCEACOGRAPHIC DATA MANAGEMENT , 23-27 JANUARY 2017, MAPUTO, MOZAMBIQUE Prepared by: Harrison Ong’anda, National Coordinator, Kenya National Oceanographic Data Center (KeNODC) honganda@kmfri.co.ke, hochieng2003@gmail.com

The WOD is the largest available, online, free ocean database Data range from >200 years old to stations within the past few years Constantly updated, includes a synchronizing option In-situ only, no remote sensing No instrumental time-series - e.g. tide gauge, current meter About 30 parameters 12 types, depending on measurement methods - ship stations, drifters, diving pinnipeds, etc. Uses cruise/station/depth/date/time paradigm for data organization Includes quality flags for all measurements

Downloading the data is easy and fast: Download zipped collections in a venerable, 80-character "archive format" Also download or link to huge collection of metadata for each ocean station Data can be quickly loaded into Ocean Data View (ODV) to create a "collection" Native WOD structure can be used Other structures (stored in ODV) can also be used

Obtaining area-specific data marine data from WOA Click on https://www.nodc.noaa.gov/OC5/SEL ECT/dbsearch/dbsearch.html check GEOGRAPHIC COORDINATES, and DATASET The OBSERVATION DATES item can also be checked, Now click BUILD A QUERY

WODSelect has created a query form based on GEOGRAPHIC COORDINATES and DATASET type (the fields you selected above). In the GEOGRAPHIC section, enter coordinates that are 1 degree larger than the area-of-interest polygon.  This gives you a margin of data around the Mozambique area to avoid "edge effects" in calculations

In the dataset section, check these items (or more, or fewer In the dataset section, check these items (or more, or fewer...up to you).  Then click GET AN INVENTORY.

This inventory appears, indicating that nearly 8,269 stations are available (for OSD).  If you get an inventory that would be too large for your local Internet conditions, then go back and use the OBSERVATION DATES to reduce the time period. Click VIEW DATA DISTRIBUTION PLOT.

Here are all the data we specified, for Mozambique.  Click on DOWNLOAD DATA

Set up the data download as you see here: WOD NATIVE ASCII FORMAT - required by Ocean Data View software; actually GZipped DATA IN SEPARATE FILES - Never combine different data types in the same download file. OBSERVED LEVEL DATA - The original measurements; standard level data would only be estimates CHOOSE XMT/MBT CORRECTIONS - You can study this issue on your own later.  It has to do with how fast the probes fall through the water, and how depths are estimated from fall- times.  Unless you have a personal preference, just leave it at NO CORRECTIONS for now. Enter your email address (one that you can use this very day), and click EXTRACT DATA

This status message tells you that your data are being prepared for FTP transfer.

Within a few minutes, you'll receive an email like this Within a few minutes, you'll receive an email like this.  Right-click on the FTP link and select SAVE AS

What to do with the data? Save the OSD file in DATA > OCEAN > WOD > OSD with the filename osd_all_mozambique_wod.gz.  Do NOT unzip this file.  It will be used by the Ocean Data View software in zipped form. Similarly, save the other CTD and PFL files into their separate similar folders, with the automatic filenames provided by WODselect. But, because they are so similar in content, you might save the MBT and XBT data into a single folder named XBTMBT. Do NOT unzip these files.  They will be used by the Ocean Data View software in zipped form.

For data security, you can optionally rename these files (or make copies) with these filenames (changing the date, to today's date): ocldb1424265618.9272.OSD.gz  --> osd_20170121_mozambique_wod.gz ocldb1424265618.9272.CTD.gz  --> ctd_20170121_mozambique_wod.gz ocldb1424265618.9272.XBT.gz  --> xbt_20170121_mozambique_wod.gz ocldb1424265618.9272.MBT.gz  --> mbt_20170121_mozamique_wod.gz ocldb1424265618.9272.PFL.gz  --> pfl_20170121_mozambiue_wod.gz