Current alarm at the massive oil plume in the Gulf of Mexico emphasises the problem of marine pollution and how difficult it is to evaluate. The North Sea has been the test-bed for the highly advanced pollution early-warning system MERMAID during the last 20 years; this development is now aiding marine authorities around the world to keep seas clean.
MERMAID (Marine Environmental Remote-controlled Measuring and Integrated Detection) became one of the cornerstones of the intergovernmental GOOS, Global Ocean Observing System. Initially, three prototype stations were sited in the North Sea around Germany's Elbe River estuary. The project's real achievement, however, was to lay the foundations for reliable, widespread monitoring systems that provide accurate early warning of pollution, allowing marine authorities to take timely counter-measures.
Before MERMAID, most marine monitoring was dependent on infrequent ship water-sampling voyages and laboratory analyses performed weeks (even months) later - far too late for effective action. Some automated systems in the North Sea measured parameters such as salinity and temperature, but they were incapable of recording the all-revealing chemical and biological profile of water. However, MERMAID harnessed the latest computer and communications technology to provide near real-time assessment of water quality and conditions for potentially the entire North Sea and other large bodies of water.
The team developed automated equipment to detect and analyse key parameters for oxygen balance, pH (alkali/acid levels), nutrients (usually nitrates and phosphates from fertilizers in farmland run-off water), chlorophyll (indication of algae) and toxic substances (including industrial effluents, organic micro-pollutants and oil).
For the first time, it was possible to detect in real-time events such as algal blooms with associated heavy metal enrichment or the sudden release of nutrients from swollen rivers.
MERMAID was an initiative of the GKSS Institute for Coastal Research, a government-funded centre based in Germany. 'MERMAID was a great success from every point of view', says Dr Friedhelm Schroeder, who had a central role in coordinating the project and is now project manager of the advanced programme that MERMAID spawned: COSYNA - Coastal Observing System for Northern and Arctic Seas.
The project's commercial partners went on to market MERMAID modules around the world, with South American and South East Asian countries being some of the first to adopt this new technology outside Europe. Meanwhile, GKSS has continued to develop the system as the core of COSYNA, pushing ever further the technological limits of sensors and finding cheaper and innovative ways to gather data on the composition and quality of water.
Global climate change is having a major effect; warming water is provoking fish migrations while a rising level of CO2 makes the water more acidic, inhibiting the growth of organisms and threatening the food chain. Oil spills also remain a constant threat. 'If we are going to meet these threats effectively, it is essential to have a better understanding of what is happening in the North Sea. And that is only possible if we continue to improve and expand the monitoring system that began with MERMAID.'