Each glowing cell holds the fires detected by the VIIRS instrument on NASA/NOAA's NOAA-20 satellite (375 m pixels), counted on a grid. A detection is a pixel that was hot when the satellite passed, so one large fire produces many detections and fires under cloud are missed.
We kept nominal- and high-confidence detections and removed those offshore, inside towns and cities, and at persistent heat sources such as gas flares.
We acknowledge the use of data and imagery from NASA's Fire Information for Resource Management System (FIRMS), part of NASA's Earth Science Data and Information System (ESDIS). Settlement mask: Schiavina M., Melchiorri M., Pesaresi M. (2023), GHS-SMOD R2023A, European Commission, Joint Research Centre. Satellite image of the Earth: NASA Visible Earth, Blue Marble (public domain); it shows the land surface, not the clouds or conditions on these dates. Processed data (fires.json, stats.json) are available under CC BY 4.0 with these credits.