MERLIN Low Detection Efficiency Study Results: First Two Years

The Mesoscale Eastern Range Lightning Information Network (MERLIN) provides continuous lightning detection and location information for the Kennedy Space Center and Cape Canaveral Space Force Station. Weather officers at the 45th Weather Squadron utilize MERLIN data to advise space launch providers of potential lightning-related hazards preceding and during launch operations. Prior study results performed in 2015/2016 found that MERLIN's detection efficiency for lightning strokes that terminated on tall structures was lower than for strokes that attached directly to ground. A secondary study was commissioned to provide additional ground-truth data for lightning strokes to tall structures (launch pad catenary wire systems, vertical spacecraft integration buildings, communications towers, etc.) to determine if the detection efficiency results were statistically significant, and if so, utilize the acquired data to potentially modify MERLIN's algorithms to better detect strokes to tall structures. Ground-truth data (high-speed optical and electromagnetic field measurements) were acquired in 2020 and 2021 totaling 129 strokes to tall structures and 3431 strokes to nearby ground.