Median bed-material sediment particle size across rivers in the contiguous US

Abstract. Bed-material sediment particle size data, particularly the median (D50), are critical for understanding and modeling riverine transport. However, observations primarily available at individual sites. Large-scale assessment of transport limited by lack continuous regional maps bed-material size. We hence present a map D50 over contiguous US in vector format that corresponds to approximately 2.7 million river segments (i.e., flowlines) National Hydrography Dataset Plus (NHDPlus) dataset. develop four steps: (1) collect process observed data from 2577 U.S. Geological Survey stations or Army Corps Engineers sampling locations; (2) collocate these with NHDPlus flowlines based on their geographic locations, resulting 1691 collocated values; (3) predictive model using eXtreme Gradient Boosting (XGBoost) machine learning method corresponding climate, hydrology, geology, other attributes retrieved dataset; (4) estimate values without XGBoost model. expect this be useful various purposes, such as research large-scale model- data-driven approaches, teaching environmental earth system sciences, planning managing floodplain zones, etc. The is https://doi.org/10.5281/zenodo.4921987 (Li et al., 2021a).