Introduction - Environmental Modelling: Finding Simplicity in Complexity - page 2

1

Introduction

John Wainwright 1 and Mark Mulligan 2
1 Department of Geography, Durham University, UK
2 Department of Geography, King's College London, UK

policy at local, regional, national and international levels.
Models can be a means of ensuring environmental pro-
tection, as long as we are careful about how the results
are used (Oreskes et al ., 1994; Rayner and Malone, 1998;
Sarewitz and Pielke, 1999; Bair, 2001).
On the other hand, we may use models to develop our
understanding of the processes that formthe environment
around us. As noted by Richards (1990), processes are not
observable features but their effects and outcomes are. In
geomorphology, this is essentially the debate that attempts
to link process to form (Richards et al ., 1997). Models
can thus be used to evaluate whether the effects and
outcomes are reproducible from the current knowledge
of the processes. This approach is not straightforward, as it
is often difficult to evaluate whether process or parameter
estimates are incorrect, but it does at least provide a basis
for investigation.
Of course, understanding-driven and applications-
driven approaches are not mutually exclusive. It is not
possible (at least consistently) to be successful in the latter
without being successful in the former. We follow up
these themes in much more detail in Chapter 2.

1.1 Introduction

There seems to be a tradition for topics on complex
systems to start from chapter zero (after Bar-Yam, 1997).
In one sense, everything in this topic arises from the
invention of the zero. Without this Hindu-Arabic inven-
tion, none of the mathematical manipulations required to
formulate the relationships inherent within environmen-
tal processes would be possible. This point illustrates the
need to develop abstract ideas and apply them. Abstrac-
tion is a fundamental part of the modelling process.
In another sense, we are never starting our investiga-
tions from zero. By the very definition of the environment
as that which surrounds us, we always approach it with
a number (non-zero!) of preconceptions. It is important
not to let them get in the way of what we are trying to
achieve. Our aim is to demonstrate how these preconcep-
tions canbe changed and applied toprovide a fuller under-
standing of the processes that mould the world around
us. From this basis, we provide a brief general rationale
for the contents and approach taken within the topic.

1.3 Why simplicity and complexity?

1.2 Why model the environment?

In his short story 'The Library of Babel', Borges (1970)
describes a library made up of a potentially infinite num-
ber of hexagonal rooms containing topics that contain
every permissible combination of letters and thus infor-
mation about everything (or alternatively, a single topic
of infinitely thin pages, each one opening out into further

The context formuch environmentalmodelling at present
is the concern relating to human-induced climate change.
Similarly, work is frequently carried out to evaluate the
impacts of land degradation due to human impact. Such
application-driven investigations provide an important
means by which scientists can interact with and influence