This textbook presents an understanding of how basic physical descriptions can be translated into mathematical analogues that provide an opportunity to investigate environmental processes. Examples come from a range of hydrologic, atmospheric, and geophysical problems. The emphasis is on simple examples and calculations that add to understanding. The book provides a sense for the meaning of mathematical expressions, a physical feel for their relations to processes, and confidence in working with mathematical solutions. The goal of this book, in essence, is to present the timeless basic physical and mathematical principles and philosophy of environmental modeling, often to students who need to be taught how to think in a different way than they would for more narrowly-defined engineering or physics problems. Minimum prerequisites for the student reader include a knowledge of calculus through differential equations, but the book provides the mathematical and physical tools needed as the occasion arises.
