The hydrologic cycle: a complex history with continuing pedagogical implications

Historical papers relating to water often focus on a physical structure or archaeological artefact that is being investigated in order to achieve insight into the life, times or understanding of a historical culture or people. In this sense, the current paper is an anomaly in that the “artefact” motivating this historical review of the hydrological cycle was observed first in the classroom. More specifically, many years of teaching hydrology has highlighted the difficulty students often have in achieving a broad and deep understanding of hydrological processes. Several reasons could be proposed for the observed pedagogical difficulties, but what is of interest here is that a student's struggles are reminiscent of the historical ones relating to first deducing the hydrological cycle. Thus, a novel hypothesis is tentatively advanced: concepts that were tortuous or taxing to deduce historically often, and for quite similar reasons, are challenging to teach, and vice versa. While a comprehensive psychological exploration of this observation is beyond the scope of this article, a few broader connections are briefly explored.