Thunderstorm Ground Enhancement (TGE) Signatures in the Eastern Mediterranean Using Gamma Ray and Atmospheric Electricity Measurements

Abstract

Intense electric fields within thunderclouds can lead to increased flows of high energetic electrons, resulting in the generation of gamma rays and neutrons. This can be manifested as Thunderstorm Ground Enhancement (TGE), an abrupt enhancement of detectable surface particle count rates which are correlated with thunderstorm activity. This research aims to conduct a comprehensive investigation of gamma ray enhancement unrelated to Radon rainout or washout effects. We utilize lightning data from both World Wide Lightning Location Network (WWLLN) and Earth Networks Total Lightning Network (ENTLN), along with gamma ray, vertical electric field, and other atmospheric parameter measurements. Our analysis include two continuous suspected TGE events within close range (< 20 km radius) to our measurement site, which are then divided into several sub-temporal events for a more detailed analysis. Our initial analysis reveals a significant increase in gamma ray count rate, accompanied by fluctuations in the atmospheric electric field during thunderstorm activity. Interestingly, some of these fluctuations occur without any lightning throughout the course of the event. We propose several physical mechanisms based on the lower atmospheric conditions combined with our gamma ray and vertical electric field measurements. The study assesses the impact of these mechanisms and evaluates the practicality of the proposed approach.