FerryBox Whitebook.

Abstract

The Whitebook presents a scientific and technical description on a newly developed instrument for automatic measurements of a series of environmental oceanographic parameters called FerryBox which supports monitoring of the water quality of coastal and offshore waters of European seas. Thus, a contribution to a future European Oceanographic Observation System (EOOS). The principal idea is to use ships of opportunity like ferries on fixed routes to make automatic measurements of important oceanographic parameters. These measurements are made in a flow-through system where different sensor are applied to continuously measure parameters like water temperature, salinity, turbidity as a measure of the amount of suspended matter, and fluorescence as a measure of the amount of algae. The sustainability of the systems could be greatly enhanced by using automatic cleaning systems so that the effort for maintenance could be reduced. In comparison to other in situ measurement systems, the reliability and data availability of FerryBoxes is higher and maintenance costs are significantly lower. FerryBox systems have reached a state of matureness and the number of measured parameters is still increasing with focus on more biogeochemical variables. The systems are extended with new sensors and analyzers for e.g. algal composition, pH, carbon budget (pCO2, alkalinity) and on some ferry routes nutrients like phosphate, nitrate and silicate. The Whitebook describes the technical details of such FerryBox systems in detail. Furthermore, the applications of the collected data for monitoring and scientific purposes is described for different water systems like the Baltic Sea, the North Sea, the Bay of Biscay and the Mediterranean Sea. To overcome the problem of spatial scale a strong connection has been built with satellite remote sensing, which can deliver images of certain parameters (e.g. chlorophyll-a, TSM etc.) of much larger areas. Long term observations on fixed transects are a powerful mechanism to detect long-term trends in coastal and oceanographic waters. In the Baltic Sea, such time series are available for over 25 years and of great help in detecting long-term effects of eutrophication and their reduction. In other areas examples of riverine nutrient inputs can be shown. Furthermore, the continuous measurements, repeated along a certain transect within days or more often, are also very helpful to detect short-term events that can be detected by research cruises only occasionally due to the limited coverage in time. The FerryBox time series can be further used for validation and improvement of physical models and the increasing number of biogeochemical variables will be very useful for further development and improvement of eco-system models. Real-time FerryBox data can be used for data assimilation to support and enable better estimates in operational models. Furthermore, the high spatial and temporal frequency of data by FerryBox systems can provide real-time information for nearby aquaculture and fishing operations including early warning indicators for e.g. toxic algal blooms. With the introduction of new sensors for alkalinity and pH ocean acidification and the special behavior of the coastal ocean as a highly dynamic component of the global carbon budget can be followed in detail as the diverse sources and sinks of carbon and their complex interactions in these waters are still poorly understood. As most FB systems are equipped with automated water sampler this makes it possible to get water samples from certain areas on a regular basis for subsequent lab analysis. First pilot studies highlighted the feasibility for both target and non-target exploratory screening of trace contaminants. Another application of water sampling could be the investigation of the steadily growing abundance of micro plastics in the oceans which might be possible after the development of suitable analytical techniques. Compared with other marine monitoring and measuring systems FerryBoxes acquire very large amounts of data. Hence quality control, evaluation and processing of these data need to be highly automated, robust and reliable. Therefore, new procedures for data processing and evaluation have been developed for the increasing number of routinely operated FerryBoxes. The planned common European database in connection with the EuroGOOS ROOSes, EMODnet and Copernicus Marine Environment Monitoring Services (CMEMS) will help to make FerryBox data easily available and visible. In a dedicated chapter, the estimated costs for installation and maintenance of such instruments are presented. Finally, a plea for support by the European Commission (DG Mare and DG Innovation) is made to be able to extend the current routes to e.g. other parts of the Mediterranean Sea and the Black Sea and to support the overall data system within the future European Ocean Observing System (EOOS).