The Fengyun-3D (FY-3D) global active fire product: principle, methodology and validation

Wildfires have a strong negative effect on the environment, ecology and public health. However, the potential degradation of mainstream global fire products leads to large uncertainty in the effective monitoring of wildfires and their influence. To fill this gap, we produced Fengyun-3D (FY-3D) global fire products with a similar spatial and temporal resolution, aiming to serve as an alternative to and continuity for Moderate Resolution Imaging Spectroradiometer (MODIS) global fire products. Firstly, the sensor parameters and major algorithms for noise detection and fire identification in FY-3D products were introduced. For visual-check-based accuracy assessment, five typical regions with a large number of fire spots across the globe, Africa, South America, the Indochinese Peninsula, Siberia and Australia, were selected, and the overall accuracy exceeded 94 %. Meanwhile, the consistence between FY-3D and MODIS fire products was examined. The result suggested that the overall consistence was 84.4 %, with a fluctuation across seasons, surface types and regions. The high accuracy and consistence with MODIS products proved that the FY-3D fire product is an ideal tool for global fire monitoring. Based on field-collected reference data, we further evaluated the suitability of FY-3D fire products in China. The overall accuracy and accuracy without considering omission errors were 79.43 % and 88.50 % higher, respectively, than those of MODIS fire products. Since detailed local geographical conditions were specifically considered, FY-3D products should be preferably employed for fire monitoring in China. The FY-3D fire dataset can be downloaded at http://satellite.nsmc.org.cn/portalsite/default.aspx (NSMC, 2021) or at http://figshare.com (last access: 10 January 2021) with the following identifier DOI: https://doi.org/10.6084/m9.figshare.20102210 (Chen et al., 2022).