Excessive dependence on computer models of complex system behaviour

1. The large computer simulation studies that have become so much a part of the resource management and environmental assessment literature are part of the problem, not of the solution. Large-scale modelling activities meant to inform decision and policy processes are not fulfilling their promise. Such work is more adversarial than most realize. It is one-sided, presenting but one perspective on a future rich in potentialities. Quality control and professional standards are low. Data inputs tend to have obscure, unknown, or unknowable empirical foundations, and the relevance of much data, even if valid, is unknown. Such work tends to ignore the most interesting aspect of any analysis, namely the assumptions through which it was elaborated.

2. Computers help reinforce the mindset that has contributed to the disproportionate impact that Western societies have had on the degradation of the habitat. Based on a Cartesian epistemology, the use of this technology reinforces the Cartesian orientations of Western culture with its emphasis on instrumental problem solving. Use of computers ignores the importance of culture as a dimension of the current crisis. At some point the incorporation of further data on environmental damage into sophisticated computer models of change in ecosystems becomes a distraction from addressing the real challenge, namely to begin to understand the difficult task of changing the conceptual and moral foundations of current cultural practices that reinforce those environmental problems. More data may enable us to predict with greater accuracy when certain irreversible thresholds will be crossed. This will however be of little use if we do not know how to reverse the demands made by cultures whose belief systems represent the environment as a natural resource and human choices as limited only by lack of data.

For the last 20 years computer models have suggested that increasing carbon monoxide should have caused a clear global warming in the lowest layer of the atmosphere. NASA satellites have been recording the temperatures in this layer. Their measurements are thought to be precise to 0.01 degree Celsius, and have been verified by independent sampling made by balloon bourne instruments. The results of the readings show no increasing global warming trend. Computer models have predicted exaggerated warming trends for the recent past; presumably they do for the future as well.