Data for: The pace of global river meandering influenced by fluvial sediment supply

Meandering rivers move gradually across the floodplains, and this river movement presents socioeconomic risks along river corridors and regulates terrestrial biogeochemical cycles. Experimental and field studies suggest that fluvial sediment supply can exert a primary control on lateral migration rates of rivers. However, we lack an understanding of the relative importance of environmental boundary conditions, such as floodplain vegetation and sediment supply, in setting the pace of river meandering across different environmental settings. Here, we combine the analysis of satellite imagery and global-in-scale sediment and water discharge models to evaluate the controls on lateral migration rates of 139 meandering rivers that span a wide range in size, climate, and bank vegetation. We show that migration rates normalized by the channel width monotonically increase with the volumetric sediment flux normalized by the characteristic size of the river. This relation is consistent across rivers in vegetated and unvegetated catchments, indicating that enhanced lateral migration rates in unvegetated basins is likely not only facilitated by lower bank mechanical strength, but also by higher normalized sediment supply in ephemeral rivers. Using three case examples, we also demonstrate that width-normalized meander migration rates respond to spatial gradients in sediment supply caused by river impoundments, highlighting the prominent role of sediment supply in setting the pace of meander migration. Our results suggest that sediment-supply variations caused by climate, land-cover and land-use changes can lead to predictable changes in meandering river evolution and ultimately drive architectural changes in sedimentary stratigraphy.

Methods
This dataset includes all underlying data used for the associated manuscript. We include all surface water mask files (.tif), derived channel centerline files (.csv, .pkl), bar-averaged migration files, and aggregated tabular data. To work with any of the derived data, we recommend using a Python-based workflow. The dataset includes three sections:

1) Dammed_Rivers

This includes underlying data for the upstream-to-downstream comparisons of river mobility across river dams. For each included river dam, we provide files that show the study area, binary geotiffs of channel water, generated centerlines, all migration data, and samples WBMsed model sediment flux and water discharge information. There are data for 3 rivers (Flint, Iowa, and Red) included in this section.

2) Single_Rivers

This includes all underlying data for the individual river analyses included in our data compilation. We include the study location, binary Geotiffs of channel water, centerlines, migration data, and WBMsed model data. There are data for 55 rivers included in this section.

3) Tabular_Data

This includes the aggregated tabular data for the data compilations. We aggregate the 55 rivers (from the Single_Rivers section) into a tabular .csv database. We also include data from 84 additional rivers that have published migration rates. 

More detail on the file structure and data contents can be found in the README.md file. For more detail on the Python-based workflow to generate channel water masks, centerline vector products, and migration rate measurements, please see the associated software.