Abstract:
Hydrologic science has undergone transformative changes over the past 100 years, from early empirical approaches to rigorous approaches for hydrologic predictions based on the fluid mechanics of water movement on and below the land surface. Challenged by limitations of traditional Newtonian approaches, and embracing a Darwinian, co-evolutionary Earth system science perspective, the pursuit of hydrologic science and predictions is now guided by altogether new questions and methodologies, with particular focus on interactions and feedbacks between parts of the Earth system that co-evolve, giving rise to a combination of bottom-up, physically-based modeling and top-down, data-based methods of modeling and inference, and the adoption of comparative hydrology. In the emergent Anthropocene, this global, co-evolutionary view has expanded to involve feedbacks with human-social processes as well. Hydrologic science is now entering a globalization era with a focus on new phenomena that emerge from regional and global teleconnections of the expansion of the human footprint, calling for the adoption of novel Wegenerian approaches to understand the Earth system and the role of water in it. In this lecture, I will present key milestones in the transformation of hydrologic science, the growth in hydrologic understanding, and the evolution in the analysis and prediction methods used in hydrologic research and practice.