Monthly average NDVI for the 86 Irrigation Districts in Mexico (from 2016-2017 to 2025-2026)

The monthly Normalized Difference Vegetation Index (NDVI) dataset was generated using Landsat 8 and Landsat 9 surface reflectance imagery within the Google Earth Engine (GEE) platform. The data processing workflow comprised three main steps: Filtering Image Collections: Landsat 8 scene collections were filtered spatially by the boundaries of each irrigation district polygon in Mexico and temporally into monthly intervals across the study period. Cloud Removal and Mosaicking: Cloud and shadow masking algorithms were applied to individual scenes. The clean, cloud-free images for each month were then mosaicked to achieve complete spatial coverage across each irrigation district polygon. Monthly Mean NDVI Aggregation: For every calendar month, the pixel-level NDVI values within each irrigation district polygon were averaged, resulting in a single monthly mean NDVI value per district. Months with persistent cloud cover or missing scene coverage were assigned a value of 0 to denote missing data. Organization by Agricultural Cycle: The resulting monthly NDVI values were structured by agricultural year, defined from October through September to align with the primary agricultural cycle and capture the full phenological trajectory of crops from sowing to harvest * If the month is empty, this indicates that no cloud-free imagery is available for that period to generate the orthomosaic.