Flux flummoxed: A proposal for consistent usage

Abstract

This technical commentary shows that the most appropriate definition of flux, as related to ground water, is that used in the field of transport phenomena. With respect to transport phenomena, the flux of some quantity is defined as the flow rate of that quantity per unit area. Because flux is defined with respect to a direction, flux is a vector at each point in space. Vectors have special properties and implied meaning in both mathematics and continuum mechanics. I propose that the transport definition of flux be used consistently in technical presentations, published papers, books, and earth science classrooms. Consistent usage will help in teaching the next generation of hydrogeologists that flux has a definite meaning in science. © 2006 National Ground Water Association.