Surface Turbulence Reveals Riverbed Drag Coefficient

Abstract Flow in rivers and the coastal ocean is controlled by frictional force exerted on water riverbed or seabed roughness. The typically characterized a drag coefficient C d , which estimated from bulk measurements often assumed constant. Here, we demonstrate relationship between bed roughness surface turbulence that can be used to make remote estimates of . We observe regions with larger result greater turbulent kinetic energy (TKE), transported upward river boils surface. present TKE validate this comparing remotely sensed those situ measurements. Thus, our results provide an approach for estimating bottom based entirely data, including their spatial variability, improve modeling discharge morphodynamics data‐poor regions.