Extinguishing the Fiery Skies: The History and Modern Prospects of Lightning Suppression within Thunderstorms

Abstract It has been over 75 years since the concept of directly suppressing lightning by modifying thunderstorm cloud processes was first proposed as a technique for preventing wildfire ignitions. Subsequent decades produced a series of successful field campaigns that demonstrated several techniques for interrupting storm electrification, motivated in part by the prospect of protecting Apollo-era rocket launches from lightning strike. Despite the technical success of these research programs, funding and interest diminished until the final field experiment in 1975 marked the last large-scale activity toward developing lightning prevention technology. Having lost widespread awareness over the ensuing 50 years, these pioneering efforts in experimental cloud physics have largely been forgotten, and this approach for mitigating lightning hazards has fallen into obscurity. At the present day, risks from lightning-ignited wildfires to lives, property, and infrastructure are once again a major topic of concern. Similarly, the rapid development of an emerging commercial space sector is placing new demands on airspace management and launch scheduling. These modern challenges may potentially be addressed by a seemingly antiquated concept—lightning suppression—but considerations must be made to understand the consequences of deploying this technology. Nonetheless, the possible economic, environmental, and societal benefits of this approach merit a critical reevaluation of this hazard mitigation technology in the current era. Significance Statement This article reviews the history of two large research programs that developed techniques to reduce lightning in thunderstorms. Project Skyfire began in the late 1940s in an effort to prevent lighting-ignited wildfires by inhibiting cloud charge generation processes. Project Thunderbolt started in the early 1960s as an attempt to protect spacecraft from lightning during launch and reentry by neutralizing electric fields in nearby storms. Both projects demonstrated some success in modifying the number, frequency, or characteristics of lightning strikes, but limitations in weather-sensing technology of the era prevented clear evaluation of these approaches. By the late 1970s, both projects had ended. Following subsequent technological advances, reevaluating these forgotten techniques may provide a pathway for developing modern lightning hazard mitigation technology.