Mapping the Onset of Paddy Flooding Using SAR Data: Regional Variations in Northern and Eastern Saitama, Japan

This dataset provides shapefiles summarizing the estimated flooding start dates of rice paddies in Saitama Prefecture, Japan, aggregated to the Japanese 4th-order mesh grid (approximately 500 m). Flooding timing was estimated using Sentinel-1 SAR and Sentinel-2 optical imagery for two years, 2021 and 2022. For each mesh cell, the dataset stores the area (m²) of paddy fields classified into six categories: Unclsfd: unclassified (less than 5 pixels within a field polygon), Nonflooded: non-flooded fields, Early I: late April, Early II: early to late May, Normal: late May to early June, Late: late June to early July (corresponding to wheat–rice double cropping). These data can be used to analyze spatiotemporal variation in agricultural practices and their ecological impacts at a landscape scale. Please note that the estimates are subject to uncertainties related to image availability, cloud cover, and classification thresholds.