Ifanadiana Sentinel2 NDWI-GAO

This dataset contains Normalized Difference Moisture Index (NDMI) values, also known as Normalized Difference Water Index (NDWI-GAO), extracted from Sentinel-2 images for areas surrounding four main villages per fokontany.NDWI-GAO values were extracted within a 1 km buffer around each village, and a weighted average of the values was calculated based on the number of buildings per village.

Columns :
- comm_fkt : name of fokontany using standardized ‘new_commune’_’fokontany’ nomenclature
- vill_ndwigao : ndwi_gao values calculated from Sentinel-2 images
- date : date in format: YYYY-MM, corresponding to year and month

Data and Resources

Additional Info

Field Value
Source Copernicus data
Author Michelle Evans
Maintainer RANDRIANJATOVO Tokiniaina
Last Updated August 20, 2025, 14:27 (UTC)
Created July 16, 2025, 15:31 (UTC)
Data link https://gitlab.com/pivot-sci-apps/smaller-backend/-/blob/main/data/model-variables/vill_ndwigao.csv?ref_type=heads
Processing steps Processing and treatment of images using Sen2Chain : Download L1C (top of atmosphere) products from available suppliers / Processing of L1C to L2A (bottom of atmosphere) products / Calculation of cloud masks and radiometric indices; Calculation of NDWI-GAO using the following equation: (B08 - B11) / (B08 + B11) Extraction of NDWI-GAO values from Sentinel-2 imagery. Definition of a 1 km buffer around each major village. Calculation of a weighted average of NDWI-GAO values based on the number of buildings per village.