Estimation of North Korea's paddy harvest area in 2020 by Sentinel1

Abstract

We used Sentinel1 time series data for the years 2017 and 2020 to determine the harvested area and its percentage within the paddy range. We calculated the average values of VH and VV for the sample points in the paddy fields at each scene and examined the changes in position in the VH-VV plane, then found that they followed a certain path. Based on the graphs, we estimated the threshold values for estimating the extent of paddy fields and for the harvested area, respectively, and then estimated the harvested area and paddy area. The results showed that the ratio of harvested area in 2017 was 93% of the paddy area while in 2020 it was 75.5%.