Environmental Engineering Reference
In-Depth Information
Chapter 1
Introduction
1.1 Environmental Modeling Using MATLAB
®
There are various types of models in the environmental sciences, and surely there is
no unique opinion about the essence of an environmental model. Differences may
mainly concern the scope of the models and the modeling methods. Concerning the
scope, this topic is relatively open; i.e. examples from different branches of
environmental science and technology are included, mainly from the hydrosphere
and the geosphere, and also from the biosphere and the atmosphere. However, the
examples are selected for demonstration purposes and can in no way represent the
vast variety of phenomena and approaches, which can be met in publications and
studies of all types of environmental systems.
Concerning the methods, the topic does not represent the entire field either.
In this topic modeling is
process-oriented
and
deterministic
. These two terms
characterize almost all presented methods, which, according to many opinions,
represent the most important approach to understand environmental systems. There
are environmental problems, for which other approaches not tackled here work
more successfully. Statistical or stochastic methods are not mentioned, for example.
Data processing, either graphical or numerical, as for example in Geo-Information
Systems (GIS), appears rudimentary in this topic.
Processes are in the focus of the presented approach. In the modeling concept of
this topic processes can be of physical, chemical or biological nature. The repro-
duction of biological species is a process, death is another; degradation of biochem-
ical species, or decay of radioactive species are other examples. Some relevant
processes are explained in detail: diffusion, dispersion, advection, sorption,
reactions, kinetic and/or thermodynamic and others.
A view into journal or topic publications shows that models of the treated
kind, process-oriented and deterministic, are applied to different environmental
compartments, to different phases and to different scales, as well as to multi-phase
and multi-scale problems. There are models of the entire globe, of earth atmosphere
and oceans, of the global atmosphere, of the sea, of rivers, lakes and glaciers, of
