4 
INTRODUCTION 
In order to be able to identify, understand, and predict global environmental changes, it will be 
necessary to carry out research programmes aimed at increasing our knowledge of the 
behaviour of the oceans within the global atmosphere-ocean-ice-land system and to routinely 
monitor the marine environment through long-term observation programmes. Global changes 
may, for example, affect the marine environment of the European waters, shipping, climate, 
agriculture, the energy industry, freshwater resources, tourism, and the insurance industry. 
The oceans serve as habitats, they are indispensable for transportation, and they are suppliers 
of vital resources. Sea water is capable of storing extraordinary amounts of heat for long 
periods of time, transporting it over long distances and releasing it again. Up to the present, 
the oceans have absorbed more greenhouse gases from the atmosphere than they have 
released, thus reducing the greenhouse effect. The North Atlantic Ocean plays a unique role in 
this respect. 
Life in Europe is influenced decisively by the special characteristics of the Atlantic Ocean, 
especially by the transport of heat from subtropical regions to the polar regions via the Gulf 
Stream/ North Atlantic Current/ Norwegian Current System, which creates the favourable 
environmental conditions prevailing in Central and Northern Europe. 
There is clear evidence of global and regional environmental changes due to anthropogenic 
influences, among other factors. In the past 100 years, air temperatures near the ground have 
increased by an average 0.7°C worldwide. According to Hasselmann, these observed 
temperature changes are of anthropogenic origin with a probability of 95%. At the Cuxhaven 
gauge station, a sea level increase of 16 cm has been recorded over the past 100 years. 
Whether this is due to a rising sea level or to land subsidence remains to be investigated. 
The oceans have also become a collecting basin for substances released by human activities. 
Water pollution through substances which do not normally occur in the ocean, or only at much 
lower concentrations, may threaten the health of marine communities. Increasing nutrient 
inputs lead to higher phytoplankton productivity and, under certain circumstances, to 
temporary oxygen depletion in sea areas which normally have sufficient O2 levels. Elevated 
levels of heavy metals such as mercury compounds may cause malformations of living 
organisms. Moreover, contaminants may become enriched in marine organisms and render 
them unsuitable for human consumption. Similarly detrimental effects are also caused by 
intensive exploitation by fisheries, exploitation of natural resources, shipping, and tourism. 
This type of damage is particularly severe in near-shore sea areas. 
Large ocean areas suffer from overfishing. High profit orientation and improved technologies 
have led to a strong reduction of fish stocks. There still are no common concepts or 
agreements on how fish stocks can be protected and harvested at the same time. For an 
efficient management of fish stocks, it will be necessary to improve scientific knowledge on 
the natural fluctuations and processes governing the diversity and abundance of species. 
Oceanography is undergoing fundamental changes. Marine environmental studies so far have