REVOLUTIONS IN OBSERVATION DRIVEN HYDROLOGIC SCIENCE, THEN AND NOW

Revolutionary steps in science often hinge on new observational capabilities driving theoretical insight. So it was with Henry Darcy, who over four days in the fall and winter of 1855-56 performed a series of experiments in a Dijon hospital, then analyzed the collected data to hypothesize that flow in porous media is a linear function of hydraulic head gradient. Since then, the history of hydrologic science is marked by mostly small evolutionary steps, often driven by a modest advancement of observational capabilities and providing new answers to familiar questions. Where are the larger revolutionary steps that suggest important, new questions that no one had previously thought of? Since Darcy’s time there have been only a few such questions in our science. It is time to change the nature and scope of hydrologic science, for example by making it truly observation rich. In response to this imperative the boundaries between the various sub-disciplines of hydrologic science are falling, while community organizations are rising to meet the challenge of a new integrated science, including organizations dedicated to providing a leap in observational and analytical capability. Darcy’s own career provides some guidance to a new integrated hydrologic science, which, like Darcy before, must serve both society and revolutionary science. Will we exploit these new opportunities to do both?