Description
Description :
This dataset contains Enhanced Vegetation Index (EVI) values from Sentinel-2 images. The EVI is calculated following Sen2Chain. Data has been available from October 2015, with an original spatial resolution of 10m and a temporal resolution of 6 days, updated every 6 days. The values are extracted from a 1-km buffer around the 4 major villages in each fokontany, then a weighted average is calculated based on the number of buildings per village to give a fokontany-level value.
Columns
comm_fkt
name of fokontany using standardized ‘new_commune’_’fokontany’ nomenclature
vill_evi_sen2
evi values calculated from Sentinel-2 images
date
date in format YYYY-MM
corresponding to year and month
Additional Info
✍️ Author
🔧 Maintainer
🗓 Last Updated
March 11, 2026
🔹 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; Extraction of values from a 1 km buffer around villages, followed by weighted-mean based on the number of buildings per village to calculate a fokontany-level value. All spatial processing was doing using the Sen2Chain algorithm. https://espace-dev.frama.io/sen2chain/ 6-day values are aggregated into a monthly mean by smoothing the full time series of data using a cubic spline to estimate weekly values which were then averaged to a monthly mean following Evans et al. 2025 (doi: 10.1186/s12936-025-05266-0)