Lightning ignition is the major cause of natural wildfires in several regions worldwide. Determining if wildfires in remote uncontrolled areas result from natural lightning as opposed to anthropic action is a relevant and yet-unsolved challenge for large regions of the planet, with scientific and management implications ranging from environmental conservation to mitigation of climate-related emissions of gases and aerosols. Brazil is the country with one of the highest occurrences of lightning (50 to 100 million/year) and which is also subject to numerous and vast wildfires (up to ∼600 × 10³ km²/year) affecting all its biomes. To quantify natural fires we combined cloud-to-ground (CG) lightning and CG dry-lightning (CGDL) detected by a ground network, with fire pixels mapped by satellite remote sensing (AQUA, S-NPP and NOAA-20) over ∼1,8 × 10⁶ km² in Central Brazil, between 2015 to 2019. Lightning ignition candidates were selected based on the distance between fires and lightning in time and space. The selected cases were investigated according to annual and monthly distributions in space and time, to local weather at the time of occurrence and, electrical characteristics related to ignition. Space-time distributions of CG lightning, CGDL and of active fires were also analyzed. Results showed that the CGDLs pattern is not different from that of the overall CG lightning, with both presenting similar kernel density, polarity and peak current. The lightning candidates indicated predominance of negative polarity and peak current frequency below 20 kA. In this range, average values for weather conditions for CG lightning matched to fires (CGDL matched to fires) had: precipitation 6 mm (< 1 mm), relative humidity 57 % (48 %), and temperature ∼30°C and wind speed of ∼ 2 m.s⁻¹ for both. The results showed that satellite detection of active fires is a useful tool to identify lightning-induced wildfires.

闪电点火是全球多个地区自然野火的主要原因。确定偏远不受控制地区的野火是否由自然闪电引起，而不是人为行为是地球上大部分地区的一个相关但尚未解决的挑战，其科学和管理影响范围从环境保护到减缓与气候相关的气体排放和气溶胶。巴西是闪电发生率最高的国家之一（每年 50 至 1 亿次），同时也遭受无数巨大的野火（高达 ∼600 × 10 ³ km ²/year) 影响其所有生物群落。为了量化自然火灾，我们将地面网络检测到的云对地 (CG) 闪电和 CG 干闪电 (CGDL) 结合起来，并通过卫星遥感（AQUA、S-NPP 和 NOAA-20）映射的火灾像素超过 ∼ 1,8 × 10 ⁶公里²2015 年至 2019 年在巴西中部。根据火灾和闪电在时间和空间上的距离选择了闪电点火候选者。根据年和月在空间和时间上的分布、发生时当地的天气以及与点火相关的电气特性，对选定的案例进行了调查。还分析了 CG 闪电、CGDL 和活动火灾的时空分布。结果表明，CGDLs 模式与整体 CG 闪电的模式没有区别，两者都呈现相似的核密度、极性和峰值电流。候选闪电表明负极性和峰值电流频率低于 20 kA。在此范围内，与火灾匹配的 CG 闪电（与火灾匹配的 CGDL）的天气条件平均值为： 降水 6 毫米（<^-1为两者。结果表明，对活跃火灾的卫星检测是识别闪电引发的野火的有用工具。