Analysis of Lightning Parameters and Precipitation Associated with Lightning-Ignited Wildfire in the Contiguous United States

Abstract:
This study explores the influence of lightning characteristics and precipitation on the ignition of Lightning-Ignited Wildfires (LIWs) across the contiguous United States. Utilizing a dataset that encompasses both fire and non-fire lightning strikes, we examine the statistical significance of lightning peak current and multiplicity, as well as the role of precipitation measured at different temporal scales. Our findings indicate that while there are statistically significant differences in the peak current and multiplicity of lightning strikes that lead to fires, these differences exhibit small effect sizes, suggesting limited practical impact on fire ignition. In terms of precipitation, our analysis reveals a consistent trend across various timescales: higher precipitation correlates with a decreased likelihood of LIWs, evidenced by moderate to considerable effect sizes, particularly with longer-duration precipitation measures. These results underscore the significant mitigating effect of precipitation on wildfire risks and suggest the interplay between precipitation and other environmental factors is more critical than lightning characteristics in LIW dynamics.