Irrigation Timing Retrieval at the Plot Scale Using Surface Soil Moisture Derived from Sentinel Time Series in Europe

The difficulty of calculating the daily water budget irrigated fields is often due to uncertainty surrounding irrigation amounts and timing. automated detection events has potential greatly simplify this process, combination high-resolution SAR (Sentinel-1) optical satellite observations (Sentinel-2) makes feasible through use a surface soil moisture (SSM) product. motivation behind study utilize large dataset (collected during ESA Irrigation + project over five sites in three countries years) analyze performance an established algorithm test improvements. study’s main findings are (1) scores decrease with SSM observation frequency; (2) as frequency increases, which was supported by better France (more sprinkler irrigation) than Germany localized irrigation); (3) replacing original model force-restore resulted improvement about 6% F-score narrowed error on cumulative seasonal irrigation; (4) Sentinel-1 configuration (incidence angle, trajectory) did not show significant impact retrieval irrigation, supposes that affected these changes. Other aspects allow definitive conclusion algorithm: lower obtained small NDVI compared were counter-intuitive but may have been larger number high vegetation periods; merging different runs interpolating all data for one run produced comparable F-scores, estimated sum around −20% reference best cases.