NDWI Water Index

Normalized Difference Water Index. This index represents the water content of the plant crown and varies between -1 and 1. High values indicate higher water content The common range for green vegetation is between -0.1 and 0.4. Raster format with 1 x 1 meter resolution - The layer was produced with ENVI software from hyperspectral aerial images (364 bands) acquired on 20 July 2022. The formula used for the calculation of the index is as follows: ((ρ857 - ρ1241) / (ρ857 + ρ1241))归一化差异水指数（Normalized Difference Water Index）。该指数用于表征植物冠层的含水量，取值范围介于-1至1之间，数值越高则代表含水量越高。绿色植被的该指数常见取值区间为-0.1至0.4。该数据图层采用栅格（Raster）格式，分辨率为1米×1米。该图层由ENVI软件基于2022年7月20日获取的364个波段高光谱航空影像（hyperspectral aerial images）生成，指数计算公式如下：((ρ857 - ρ1241) / (ρ857 + ρ1241))