Research Topics - In-situ Measuring Systems
Water Quality Measurements for Process Studies
The “In-situ Measuring Systems” department deals with answering questions regarding water quality and the quantification of chemical-biological processes in coastal waters. To do this it is necessary to carry out long term measurement and process studies. However due to the fact that many of the processes which occur in coastal waters exhibit a high degree of temporal variation and sectional heterogeneity the use of field campaigns from research vessels which are carried out 2-4 times per year aren't enough for an understanding and modeling of the environment. Therefore these campaigns which due to cost reasons can only be taken sporadically, have to be supplemented by the automated measurements taken, for example by cruise ships which regularly travel through the areas to be tested.
By using a combination of ship campaigns, continuous In-situ measurements, remote sensing and statistic-numerical evaluation it is possible to put together a picture of the processes which determine the water quality. These scientific findings are then used to develop and optimize more cost-effective monitoring techniques. Most of the work is carried out in the North Sea, however the methods that are developed are also put into use in international projects e.g. in Indonesia and Brazil.
Development of Measuring Systems
To carry out our scientific work we normally use instrument carriers e.g. automatic buoys and instrument systems, which are already available commercially.
However if suitable systems can’t be supplied or they do not fulfill our requirements we work together with industrial partners to develop new systems or adapt existing ones. One example of this is the development of an automated measuring system that measures water quality autonomously on regular ship cruises. The collected data relating to oceanographic and biological-chemical parameters can then be transmit to shore.
One very important part of our work is to improve the quality of the measuring systems developed and to demonstrate and document their accuracy.
Development of Sensors
In order to carry out automated measurements of biological-chemical parameters it is necessary to have robust sensors or analyzers which provide long-term stability.
Many of the sensors which are used for oceanographic parameters already fulfill these requirements. They will be improved, quality checked and used into in-situ measuring systems. However, for many biological-chemical parameters suitable sensors are not available. In order to overcome this shortage, suitable sensors and analyzers are either developed in this department.
Data Evaluation and Interpretation
During all automated measurement processes, but especially during the FerryBox cruises, large amounts of data are collected. They are initially checked automatically and for plausibility and stored in a database. This is followed by a quality assessment procedure using comparative readings.
The actually data evaluation is carried out by statistical time series analysis. Additional optical satellite data is also used for comparison and interpretation of the data. In order to assess water quality and to derive water quality management options additional numerical water quality models (process models) are applied.