Supplemental Material: Dune interactions record changes in boundary conditions

Supplemental text describing methods for dune-field digitization, digitization sensitivity analysis, sediment flux calculations, and turnover time scales; validation for turnover time scales; terrestrial wind data sensitivity analysis; three supplemental tables and five figures; and all compiled data. ERA5-Land data are available from the Copernicus Climate Data Store (https://cds.climate.copernicus.eu/).