Chaopeng Shen received the Ph.D. degree in environmental engineering from Michigan State University, East Lansing, MI, USA, in 2009. He is an Associate Professor with the Department of Civil Engineering, Pennsylvania State University, University Park, PA, USA. Raised academically as a physics-based hydrologic modeler, his efforts in recent years have focused on harnessing big data and machine learning (ML) opportunities in advancing hydrologic predictions and improving physical understanding with ML. His group was a pioneer in introducing long short-term memory networks as a dynamical modeling tool into hydrology, and, later, in connecting physical process descriptions and ML via differentiable programming for parameter and process learning. He has written technical, editorial, review, and collective opinion papers on deep learning to call to attention the emerging opportunities.