Forest loss and disturbance alerts
Landsat, Sentinel-2 and Sentinel-1 time series are classified to map annual loss and near-real-time disturbance, with radar used where cloud blocks optical sensors.
The Global Centre for Risk and Innovation (GCRI)
Satellites observe forests, wetlands, coasts and the ocean surface repeatedly and across borders, which field surveys cannot. Earth observation maps ecosystem extent, change and some aspects of condition, and it gives a consistent record for places where no one monitors on the ground.
Earth observation for ecosystems is the use of satellite and airborne sensors to map ecosystem extent, change and aspects of condition across borders and over decades. It detects forest loss and disturbance, tracks wetlands and mangroves, and measures vegetation structure with lidar where no one monitors on the ground.
The working screen behind this method: its structure, terms and states. Names are placeholders and values illustrative.
Biodiversity · Earth observation for biodiversity · Run R-8579
revisit and swath
stratified sample
| Water | 91 | 97 | 96 |
| Cropland | 89 | 87 | 287 |
| Built-up | 82 | 79 | 124 |
| Forest | 91 | 88 | 103 |
Earth observation and remote sensing gather information about the Earth's surface and atmosphere from airborne and spaceborne sensors. They provide consistent, repeatable measurements over areas that are hard to monitor on the ground. In biodiversity and nature, climate and hazards and oceans and coasts, earth observation maps exposure, damage and environmental change across borders and sectors. It supports rapid assessment after disasters and long-term monitoring of risk drivers. The canonical description is on the STEM Commons.
Landsat, Sentinel-2 and Sentinel-1 time series are classified to map annual loss and near-real-time disturbance, with radar used where cloud blocks optical sensors.
Radar and optical time series track flooding regimes, wetland extent and mangrove change, separating seasonal variation from conversion.
Spaceborne lidar and radar estimate canopy height and biomass, and spectral indices track phenology and stress as proxies for ecosystem condition.
Each term as this page uses it. Where a standard-setting body defines the term, the wording follows that body.
| Term | Definition |
|---|---|
| Spaceborne lidar | A laser instrument in orbit, such as GEDI, that measures canopy height and vertical structure. |
| Disturbance alert | A near-real-time satellite signal of forest change, such as GLAD or RADD alerts, needing confirmation. |
| Land cover change | A change in the physical cover of the land surface, such as forest to cropland, detected between dates. |
Mountain ranges, deserts, wetlands, glaciers and reefs, and how remote each division is from large cities, shown for Pacific Island states as an example geography for this subject.
Data from the source register feeds the methods; calibration and an independent test gate the estimate and its limits; the decision stays with the competent authority.
Fig. 01Nodes carry their type, metrics and state; connectors show what feeds what; the gates are the validation steps; the timeline is one application. Design of the method's use, not a record of a run.
Datasets and records used by earth observation and remote sensing on this platform, with the role each plays and the label its values carry. Sources are listed in the source register.
| Data | Role | Label |
|---|---|---|
| Landsat and Sentinel-2 optical imagery | Land cover and change | OBSERVED |
| Sentinel-1 and ALOS PALSAR radar | Forest and wetland mapping through cloud | OBSERVED |
| GEDI spaceborne lidar | Canopy height and structure | OBSERVED |
| Copernicus Marine ocean colour and temperature | Marine productivity and heat stress | OBSERVED |
| ESA WorldCover | Land cover baseline | MODELLED |
Products are assessed against ground reference data using accuracy matrices and independent samples. Cross-calibration between sensors checks consistency over time.
| Check | How it is done |
|---|---|
| Accuracy assessment with area estimation | Maps are scored against a probability sample of reference points, and areas are adjusted for classification error |
| Cross-sensor consistency | Trends are checked across sensors and processing versions before they are reported |
| Field calibration | Structure and condition proxies are calibrated against inventory plots |
| Coverage reporting | Cloud, revisit gaps and missing scenes are reported as no data, not as no change |
Clouds, revisit gaps and mixed pixels limit what can be observed. Changes in sensors and processing can create artificial trends.
Space and Earth Observation stewards earth observation and remote sensing for the Consortium and reviews how it is applied across platforms.
The current service level is R0: information and enquiries. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.