Agricultural and forestry satellite for agriculture and forestry monitoring are scheduled to be launched in the Republic of Korea in 2025. The Agricultural and Forestry Satellite CAS500(Compact Advanced Satellite 500)-4 is a multi-spectral satellite with a spatial resolution of 5 m and with a revisit cycle of 3 days. Prior to launch, this study intends to develop a NDVI composite technique to minimize the effect of clouds. A high-altitude Korean cabbage field (<67ha), which has a relatively large area as a single crop field in Korea, was selected as the study area. Sentinel-2A/B (10m spatial resolution, 5-day revisit cycle) acquired from May 2019 to July 2021 for the study area was used. For monthly compositing, the MaxNDVI technique, which is a representative composite technique, and the recently suggested score-based composite technique were applied and compared. The score-based method calculates the fitness score for compositing for each pixel by assigning various factors and weights to minimize the effect of clouds during NDVI composite and maximize temporal representativeness. Therefore, the reflectance of the pixel with the highest score is used for compositing. The reflectance composite image produced in this way is converted to NDVI. Although both composite techniques minimize the effect of clouds, both results show that MaxNDVI shows high NDVI at the end of the month at the time of early growth after sowing, whereas the score-based technique shows NDVI at the middle of the month. Compared to the MODIS composite data from 2019 to 2021, the monthly composite data of Sentinel-2 NDVI showed various growth patterns by site in more detail.
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