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Ten areas in Rondônia, Brazil. Sentinel-2 imagery from 2018 and 2024.

NDVI measures vegetation. The cutoff decides which patches count as dense vegetation: lower includes more; higher is stricter.

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Highlight changes to see where patches crossed the cutoff between 2018 and 2024. The 2018 image stays clear for comparison.

Select a point on either image to try the land classifier on a 640 m patch.

Vegetation loss can indicate deforestation, but crops and dry conditions can also change NDVI. These results do not confirm tree loss.

How this estimate works

NDVI is calculated from near-infrared and red reflectance: (NIR − Red) / (NIR + Red). Each complete 64 × 64 pixel patch is compared using only pixels valid in both years. Patches with less than 90% shared valid data are excluded, along with incomplete patches at the image edges.

A patch is a forest proxy when its mean NDVI meets the selected threshold. Loss means it met the threshold in 2018 and fell below it in 2024. The percentage is lost patches divided by initial forest-proxy patches. Hectares count valid pixels in lost patches at 10 m resolution.

These are cloud-masked median composites from June 1 to September 30, with the end date excluded, in each year. Both images share the same grid and display colour stretch.

High NDVI also occurs in crops and other vegetation. These estimates have not been validated against an independent forest-loss dataset. Changing the threshold changes the estimate.