A colleague who is the head of a water planning agency in a large neighboring county and who was under some pressure to use the types of models discussed in this book told me, “You can either guess the input to the models or you can guess the results. As an engineer with long experience with the water systems that I manage I would rather guess the results because I have a feel for what is likely. If I use the models based upon very imperfect data my experience is completely ignored, and who knows what the results really mean.”
Basta, Bower, and their coauthors have done an excellent job in summarizing the state of the art of the models available for analyzing natural systems with an eye to environmental quality management. What a sorry tale they tell. In the terrestrial, the aquatic, and the atmospheric environment the message is the same; the mathematical formulations have run ahead of the conceptual understanding of the underlying processes and the measurement of data on these processes.