Bayesian analysis of the detection performance of the Geostationary Lightning Mappers

Geostationary Lightning Mappers aboard GOES-16, -17, and -18 have collectively provided five years of continuous observations of total lightning for a region extending from New Zealand and the Aleutians eastward to the western tip of Africa. Quantifying the detection performance of the GLM sensors is a necessary step toward accurately interpreting GLM data and combining it with lightning detections from other sensors and networks.

We compare lightning observations from the GLM sensors with each other and with reference sources including the Lightning Imaging Sensor on the International Space Station (ISS LIS) and the ground-based Earth Networks Global Lightning Networks (ENGLN) and Global Lightning Dataset (GLD360). Instead of a relative detection efficiency approach that involves assuming perfect performance of the reference sensor, we employ a Bayesian approach to estimate the upper limit of the absolute detection efficiency (ADE) of each sensor being analyzed. The results of this Bayesian analysis illustrate the geographical pattern of GLM performance as well as its diurnal cycle.