Mathematical models

MUMM studies the ecosystem of the North Sea using mathematical modelling techniques.

Did someone say 'mathematical models'?

Yes, this involves properly understanding the mechanisms that govern the way the marine ecosystem works and translating them into mathematical expressions. These are gathered together in a system of equations … which are simply an appropriate way of rewriting the old laws on conserving mass and energy.

These equations are transformed into computing programs and, using various digital methods, attempts are made to resolve them using computers with an adequate calculating capability.

MUMM's models currently deal with physical variables (water levels, currents, waves, temperature, salinity), chemical variables (mainly substances such as hydrocarbons) and biological variables (confined to the first links in the food chain). All these variables are linked to one another and the degree of complexity and uncertainty increases from the physical to the biological variables.

The theoretical results produced from the models are then carefully compared with all the observations available. This is the 'validation' phase.

An unsatisfactory validation is a sign that the mathematical expressions chosen to describe physical, chemical and biological processes are not correct. Consequently this is a good tool for guiding research towards more detailed knowledge of the marine ecosystem.

A satisfactory validation indicates that the models can be used for management purposes and to a certain extent for forecasting.

These models are first and foremost research instruments that can be used to test various scientific hypotheses virtually, that is without having to carry out costly experiments. In this case, the term used is models under development.

When these models have attained an acceptable level of maturity and reliability, they are referred to as operational models capable of providing various items of marine information and a number of marine services, similar to those which have been provided by meteorology for many years now.

 Operational models

 Models under development