The Combined Use of Sentinel-1, Sentinel-2 and Landsat 7&8 Data for Estimating Heading Date of Paddy Rice

The authors have developed monitoring system for rice growth status in the Tohoku region of Japan using satellite data. One of the important input parameters for the monitoring system is the heading date. Until now, the heading dates in the system are provided by the users on the base of field records. However, the collection of the data records is time consuming work and all users of the system cannot provide a hearing date of each field in time. For this reason, we have investigated whether the heading date can be estimated by using SAR data with NDVI of optical satellite data. In this paper, we will present the estimation method of heading date for paddy rice using the dual polarization of Sentinel 1A and 1B. The result shows potentiality to estimate the heading date of paddy rice in error range of about 6 days by combined using NDVI changes.