Major improvements in spaceborne early fire detection and small-fire FRP retrieval with the meteosat third generation flexible combined imager

Geostationary Earth Observation satellites, originally developed for weather forecasting, offer unique high temporal resolution imaging capabilities increasingly suited for detecting the fast-changing dynamics of landscape fires. The newly operational Meteosat Third Generation (MTG) satellite carries a Flexible Combined Imager (FCI) that greatly improves on the spatial, temporal and radiometric characteristics of the predecessor Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI) system. Here we describe for the first time the application of an active fire (AF) detection algorithm to FCI data, and the retrieval of fire radiative power (FRP) estimates from the detected AF pixels. The algorithm used is the Fire Thermal Anomaly (FTA) approach, currently used to generate the operational SEVIRI AF data products at the EUMETSAT Land Surface Analysis Satellite Application Facility (LSA SAF). A comparative analysis between the FCI-derived outputs and those obtained from the existing SEVIRI system is undertaken in order to evaluate the benefits provided by FCI. We also include in this comparison data products from the polar-orbiting Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) systems. Our intercomparisons made in detail over specific Portuguese and Greek wildfires, and systematically across Africa and Europe, reveals four key findings: (1) FCI detects fire onset up to four hours earlier than SEVIRI for the specific fires examined, and two hours before MODIS and four hours before VIIRS; (2) FCI generated 5× more AF pixel detections than SEVIRI, due to a much reduced minimum FRP detection threshold (∼10 MW versus ∼40 MW) enabling the detection of the many AF pixels missed by SEVIRI; (3) FCI AF detection errors of omission were 38% compared to MODIS centre-of-scan data, and 68% compared to VIIRS, substantially improving on SEVIRI's 83% and 89% respectively; while commission errors compared to these two remained low at 12% and 10% respectively; (4) FCI FRP retrievals showed very strong agreement with the matching ones provided by MODIS (r 2 = 0.97, slope = 0.93). FCI offers detections every 10 minutes over the full disk, and 2.5 minutes over Europe when rapid-scan commences after launch of the second MTG Imagery platform. The results shown here suggest that the operational active fire data products based on FCI and planned to be issued from the EUMETSAT LSA SAF using the FTA algorithm should deliver a substantial improvement in satellite-based fire monitoring across Europe and Africa compared to the already successful products currently generated from MSG. • MTG FCI offers a step-change in continuous wildfire monitoring performance • FCI detects fires 4 hours earlier than SEVIRI, 2 hours before MODIS • New FCI system identifies 5x more active fire pixels than SEVIRI • Strong FRP agreement with MODIS: 0.97 correlation, 0.93 slope accuracy • 10-minute full disk scans, planned 2.5-minute coverage for Europe operations