Underway Data

Pilot Project for a monitored investigation and transmission of oceanographic "underway" measurements on the big German research vessels, their quality control and archiving.

(02/2012 - 12/2012)

The oceanographic and meteorologic data is stored in the D-Ship system on board of the German research vessels. After each cruise the data is send on a CD to the Leitstelle in Hamburg and further on to the Bundesamt für Seeschifffahrt und Hydrographie (BSH) where the D-Ship Data is deposited into the BSH-D-Ship Ground-System (D-Ship Landsystem).

There has been no test of any sensor nor has been any data quality control. With that any failure of a sensor would not have been detected a all. 

Additional to the previous work-flow of the D-Ship CD's into the D-Ship Ground Station an additional monitoring work-flow has been established. It consist of a daily sensor testing and a quality control for each cruise.

• An automatic script has been installed on the D-Ship ship system on board of the research vessel Maria S. Merian. The script calls a Template file to download only the relevant oceanographic, meteorologic and system data from the D-Ship ship system for the last complete UTC-day. It ZIP's and store's the D-Ship extract automatically on the ship-server. 

• A VPN-client from the ships shipping company Briese has been installed at the Leitstelle in Hamburg. It enables a direct connection between the Leitstelle and the FS Maria S. Merian. Using this connection via Internet, not only enables to surf on the ship's D-Ship system and download the data, but if required change the template file or even run a manual export. The only limitation is the global Ku-band internet coverage that is not available in most parts of the southern ocean (see attached figure). 

• A MATLAB script converts the downloaded data into mat files, generates for each variable a quality flag and performs a sensor test. The tested data is then visualized. The visualization includes a map with the position and displays for each variable the according quality measure from the sensor test. The data and figures are then stored.

• If problems with any sensor get evident, one is now able to recognize the problem within one day and communicate it to the ship in order to fix the sensor problem. In case of a sensor failure, the daily sensor testing prevents a long loss of data in the order of one to two months.

• Next to the daily sensor tests water samples are taken twice a day. If an oceanographic cruise is on board, these water samples are probed for their salinity and the data is send to the Leitstelle Hamburg in order to validate the salinity data. 

The following project phase will extend the sensor tests to the FS Meteor and FS Sonne and will deal with the quality controll e.g. of the salinity data.