Modelling catastrophic change The simplest mathematical equation that represents bifurcations and catastrophic change is a first order differential equation of the form: (eqn. 1) Solving for the attractors (dX/dt = 0), it is seen that one root is X = 0 and it represents a globally unstable attractor and the other two roots are [...]
Models of oil and gas exploitation An important issue in sustainable development discourses is the depletion of finite resources of fossil fuels and minerals. The concepts of supply cost curves and reserve-production ratios (RPR) have been introduced in resource economics, in combination with learning-by-doing (see Appendix 8A.1 en Box 17.2 in Sustainability Science book and [...]
It is a very fundamental principle indeed that Knowledge is always gained by the orderly loss of information, that is, by condensing and abstracting and indexing the great buzzing confusion of information that comes from the world around us into a form which we can appreciate and comprehend. (K. Boulding) How do humans acquire knowledge? [...]
In an abstract scientific sense, modelling is a coding process and creates a relation between a ‘natural’ and a ‘formal’ system (Figure 1a; Rosen 1985). As scientists refine existing and construct new theories, there may (temporarily) be two different formal systems to describe the same natural system. An example of such complementarity is the wave [...]
There are some empirical, illustrative case-studies in which catastrophic did happen. The first classical example is the interactive dynamics between the spruce budworm, its predators and the boreal forest in North America (Holling 1986; Meadows 2008). When the budworm became a ‘pest’ and northern forests were sprayed with the insecticide known as DDT to control [...]
The astrophysicist Chaisson (2001) has proposed an interesting link between energy and complexity. Organisms can be viewed as dissipative structures: Ordered objects whose structure can be maintained thanks to a steady input of high-quality energy. The free energy flow density (ɸ) necessary to sustain such a non-equilibrium structure is a measure of complexity. It can [...]
A fragmented, disciplinary approach does not work in sustainability science. A broader perspective transcending disciplinary boundaries is needed. One framework to investigate global change phenomena in such a broader, problem-oriented setting is the syndrome approach, originally proposed by the German Advisory Council on Global Change (WBGU 1994) and later conceptualised and developed at the Potsdam [...]
Change is an elementary phenomenon in life. It is most visible in movement of matter. It is useful to look at a simple, well observable and controllable system: a mass m at the end of a spring. It is the classical model of linear elasticity, associated with the 17th-century British scholar Hooke. Change is in [...]
We humans make mental ‘maps’ of processes around us in order to live and survive. Many of those maps are simplified, based on a limited set of acquired habits and experienced events. The maps also tend to assume single and linear relationships between causes and effects. Assuming that more cars (A) cause more traffic accidents [...]
There are quite some book on system dynamics which make a connection with sustainable development problems and solutions. Based on personal contacts, I choose two for a brief intrduction. The first one is the book Managing Complexity in Social Systems - Leverage Points for Policy and Strategy (2nd ed. 2023) by Christoph Mandl. The seond [...]