Research Focus & Projects
Graphic visualisation of a long-term water temperature measurement in the North Sea with the aid of a FerryBox on board the "TorDania" cargo ship. -image: HZG-
Most of our understanding of seawater processes is based on measurements taken from individual systems at certain periods of time or at a fixed location.
These spatially and temporally limited measurements taken from research vessels, remote sensing methods (radar, satellite) and stationary stations (buoys, poles) can, however, record only a portion of the occurring processes.
Comprehensive research and analysis of marine processes is only possible when combining these “point measurements” with long-term measurements.
The Department of In Situ Measurement Systems carries out such long-term measurements, mainly in the North Sea. The time series that are thereby created consist of measurements of all quantities recorded successively with high frequency during the entire measurement process.
In order to ensure the data is usable, it is first subjected to automated quality control. This procedure rejects clearly incorrect measurement values. The data is then manually analysed for accuracy using defined parameters and entered into a database. Additional quality checks are carried out in which water samples taken at various measurement locations are analysed in the laboratory and with which the data obtained are compared.
The actual analysis of the long-term measurements is undertaken with the aid of statistical methods (time series analysis) and theoretical water quality models. Furthermore, satellite data is used for comparison of certain measurement variables, such as chlorophyll.
With the aid of long-term measurement analysis, developments can be identified and forecasts can be made. Incremental changes in coastal waters, which can only be detected by monitoring processes over several years, can then be verified and evaluated.
Coastal ocean observation has become increasingly more important for marine research in the last several years.
Coastal observation systems in the past were therefore created to record necessary data required for studying the sea. The process, however, was extremely fragmented. The research at scientific institutions in Germany and Europe was carried out separately and temporally limited.
Coastal observation systems are therefore still very different in terms of their structure and organisation, and the measured variables differ. Furthermore, each research institute has developed their own methods for systems operation and for quality control.
The goal of the JERICO project is to standardise these various approaches. The systems such as fixed stations, FerryBox and glider are to be harmonized in terms of standards, handling and integrated measurement instruments. The development and optimisation of observing systems are to be undertaken jointly. The measuring systems are also to be co-ordinated and linked in the form of a jointly operated European network.
The data obtained for oceanographic observations and forecasts are to be disseminated in Europe and worldwide. The data will also, for example, support international research on climate change. Additionally, the joint research is to contribute in implementing new technologies and research strategies for the next generation of coastal observation systems.
Further information can be found on the Jerico website.
The aim of NeXOS is to develop innovative, economical, compact and integrative multifunctional instruments that can be utilised in various mobile and fixed measurement systems and platforms.
The most varied types of measurement instruments are therefore developed: from passive acoustic sensors to optical sensors and biogeochemical sensors.
All sensors developed by NeXOS will be equipped with a standard communication protocol (Sensor Web Enablement / SWE). This will make it possible for different platforms to automatically recognise the installed interchangeable measurement instruments – comparable to a home PC that, thanks to "Plug and Play" standards, recognises connected components such as printers.
The Department of In Situ Measurement Systems is further developing the PSICAM zusammen mit der Universität Oldenburg und der Firma TRIOS weiter und optimiert es für den Betrieb in mobilen Systemen wie der FerryBox.
In addition, instruments for measuring the carbon cycle (pH values, alkalinity and CO2 concentrations) are under further optimisation in cooperation with Norwegian partners until the instruments are ready for production.
Further information can be found on the NeXOS website.
The concentration and composition of single-celled algae (phytoplankton) is an important measurement variable for describing water quality. These algae can be recognised based on their genetic make-up (DNA and RNA).
Biomolecular methods for determining DNA and RNA are especially important in phytoplankton research. The methods also enable scientists to identify organisms that are too small to be detected using conventional microscopy. Furthermore, the methods are simple, fast and suitable for routine use.
Within the framework of the EU project EnviGuard, the Alfred Wegner Institute (AWI) is further developing a biosensor for detecting phytoplankton and optimising it for use in FerryBox systems. The instrument will include automated sampling and sample processing.
The biosensor is based on the biomolecular method referred to as “sandwich hybridisation”. The principle is shown in the following schematic:
This method can be applied to many different algae simultaneously.
The data obtained provides information about the distributions, variety and temporal progression of various types of phytoplankton.
The Department of In Situ Measurements is tasked with testing and optimising the biosensor on the FerryBox systems.
Further information can be found on the EnviGuard website.
The environment in the Yellow Sea, between China and the Korean Peninsula, has been dramatically impacted in the last few decades. These environmental changes are now to be continuously observed. To this end, the project “Economical Methods for Observing Water Quality in the Northern Yellow Sea" was founded and is supported by the Federal Ministry of Education and Research.
The Department of In Situ Measurements possesses an automated, economical measurement system for large-scale observation with their FerryBox.
Together with the Institute of Coastal Research in Yantai, China, a ferry line in the Bohai Bay demonstrates the applicability of the FerryBox for observing water quality in the Yellow Sea.
Chinese scientists visit the HZG for exchanging knowledge and for training in use of the FerryBox, whereas the Department of In Situ Measurements, with the aid of a portable FerryBox, operates various measurement campaigns on board a ferry in the Bohai Bay during different seasons.
The aim is to establish economical and continuous large-scale water quality observations in the Yellow Sea with the aid of FerryBoxes and other observational methods.