Challenges in ocean observing systems
Oceans regulate the Earth’s climate and are integral to all known sources of life. Ocean processes are of biological, geological, chemical or physical nature, occurring at micro- to kilometre scales, from less than seconds to centuries, turning the understanding and the sustainable management of the ocean into a multi-scale and multi-disciplinary effort. Collection of in-situ observation of a volume that covers over 70% of the planet is also inherently challenging and remains generally difficult and costly in time and resources, with yet and so far a rather unsatisfactory result, in particular with respect to space-time resolution. Most chemical sampling methods are still experimental and expeditionary, i.e. based on costly laboratory analysis and field campaigns.
These can also only harvest data for a limited time-space window, resulting in the problem of insufficient sampling resolution, spectral aliasing and consequently erroneous information. At the other end of observation strategies, real-time or near real-time permanent ocean observatories need to be more cost-effective. As was highlighted in FP6 ESONET NoE, reducing the frequency of sensor maintenance and implementing a remote management of sensors are important targets for cost-reduction. Following this trend, new sensor system transducers are also needed, which can measure several parameters with enhanced reliability.
European marine policy makers stated in the “Ostend Declaration” of 2010 that the major challenge is now to support the development of a truly integrated and sustainably funded European Ocean Observing System (EOOS) to monitor key ocean processes. This would form the European component of the Global Ocean Observing System (GOOS), and would continuously monitor the European seas from near-coastal to open ocean, and surface waters to seafloor. Fixed and mobile observing platforms, would be used to offer real-time, or near real-time, open and standard downstream services to the public and private sectors. This system would re-establish Europe as a global leader in marine science and technology, as well as support effective management of the European maritime environment. To achieve this, more long term measurements of key parameters are required, but the costs and unreliability of ocean sensors remain a major problem.
To this end a number of challenges, mostly related to the high cost of data, need to be overcome. The general priority for all observing systems, monitoring strategies and sensor technologies is therefore to create mechanisms and technologies such that data has greater societal and scientific value, and the overall life cycle cost of sensors and observing systems is reduced. This will be achieved by innovations in data accessibility, reliability, interoperability and multifunctionality for the key ocean variables.