akar.earthSentinel-2: Definition
What is Sentinel-2? The free Copernicus optical satellite mission used for forest monitoring, EUDR checks and carbon project baselines in Indonesia.
Sentinel-2 is a European Space Agency optical satellite mission, part of the EU Copernicus programme, that images the Earth’s land surface in 13 spectral bands at 10–60 m resolution. Its data is free and open, which has made it a default source for forest and agriculture monitoring.
Why it matters
Sentinel-2 combines good detail (10 m in the visible and near-infrared bands) with frequent revisits, roughly every five days at the equator with more than one satellite in orbit. Its red-edge bands help separate vegetation types. For forest carbon projects and EUDR due diligence it is often the first dataset used to map land cover, detect change and check plots against the cut-off date.
How it is used
- Land cover and forest/non-forest maps for baselines and eligibility checks such as the 10-year rule.
- Change detection and alerting for clearing, fire and degradation.
- Vegetation indices like NDVI to track planting establishment.
- One input to biomass models, alongside radar, lidar and field plots.
Indonesia and Southeast Asia angle
Cloud is the main limitation. Over much of Sumatra, Kalimantan and Papua, many scenes are partly or fully cloudy, so analysts build composites from many dates and add radar. For EUDR, Sentinel-2 is useful for checking whether a coffee, cocoa or palm oil plot was forest around 31 December 2020, but small or irregular smallholder plots may sit across mixed pixels. See satellite verification for EUDR.
Processing has also become easier. Analysis-ready Sentinel-2 collections are hosted on several cloud platforms, so teams can build cloud-free composites, run classifications and extract plot-level time series without downloading individual scenes. That makes it practical to screen thousands of smallholder plots at low cost.
Common mistakes
- Using single-date images in cloudy regions and reading cloud shadow as loss.
- Assuming 10 m is enough to classify shade-grown agroforestry.
- Mixing Level-1C and Level-2A products without consistent atmospheric correction.
Compare with Landsat and commercial data in Sentinel vs Planet imagery.
Frequently asked questions
Is Sentinel-2 data free?
Yes. Sentinel-2 imagery is free and open under the EU Copernicus programme and can be downloaded or processed in cloud platforms.
Can Sentinel-2 show small smallholder plots?
Partly. At 10 m resolution a 1 ha plot covers about 100 pixels, enough to see cover change but not individual trees. Very small or narrow plots may need higher-resolution imagery.
Does Sentinel-2 cover the EUDR cut-off date?
Yes. Sentinel-2 has imaged the tropics since before 31 December 2020, so it can be used to check land cover around the cut-off date, cloud permitting.