2.9 Cellular Automata in Geomorphology

Cellular automata (CA) are a discrete computational approach to simulating geomorphic forms and processes. This chapter begins by describing the development and structure of the CA modeling framework, discusses how this modeling system relates to other modeling systems in geomorphology, and analyzes the historical incorporation of CA approaches into geomorphology. After highlighting these CA uses in geomorphology, this chapter discusses the advantages and disadvantages of CA modeling, looks into more detail on the issues of implementing CA models, and closes with an elaboration on the place of CA modeling in the scientific nature of geomorphology. CA have become an important part of geomorphic simulation for a variety of reasons. First, it is an extremely flexible modeling approach, allowing many different types of rules and representations to be coupled. Second, CA allow geomorphologists to choose the level of reality to be represented, from abstract toy models to highly realistic and massive CAs. Third, the normal geomorphic CA model is highly map-like, and its inputs and outputs are common maps and map-like information. This simple map-like raster CA representation also makes it quite simple and straightforward for integration with many computer platforms and software, such as geographic information systems, general mathematical solution software, or image processing software. Today, CAs are the archetype models for several geomorphic systems, and they are common in almost every branch of the geomorphic science.