FORMA Raw Output FIRMS (WRI/GFW/FORMA/raw_output_firms)

FORMA alerts are detected using a combination of two MODIS
products: NDVI (Normalized Difference Vegetation Index) and FIRMS
(Fires Information for Resource Management System). NDVI updates are
processed every 16 days, while fire updates are processed daily. Models
are developed individually for each ecogroup to relate the two inputs to
the area of clearing, using the Hansen annual tree cover loss data to train
the model. The minimum threshold to qualify as an alert is 25% of the pixel
cleared, though thresholds vary by ecogroup to minimize false positives.
Here is an example script
for a quick introduction to the FORMA datasets.

The images in this ImageCollection contain the raw FORMA data calculated after new
MODIS FIRMS data becomes available, approximately every day.

Each band gives a percentage of clearing (from 0 to 100) for
different accumulation periods. “N” is the number of days between the latest FIRMS update
and the previous NDVI update. N is given by the ‘date_delta’ property.

ndayPercentage of clearing in the last N days%
delta_ndayPercentage of clearing in the last 96+N days%
near_term_delta_ndayPercentage of clearing in the last 32+N days%


World Resources Institute / Global Forest Watch (producer, licensor)
Google Earth Engine (host)
STAC Version 0.6.2
Keywords FORMA, GFW, MODIS, WRI, daily, deforestation, forests, monitoring
License proprietary
Temporal Extent 4/7/2017, 5:00:00 PM - now
Type image_collection
GSD metersm
cube:dimensions {"x":{"type":"spatial","axis":"x","extent":[-120,180]},"y":{"type":"spatial","axis":"y","extent":[-50,40]},"temporal":{"type":"temporal","extent":["2017-04-08T00:00:00Z",null]},"bands":{"type":"bands","values":["nday","delta_nday","near_term_delta_nday"]}}