Highly dynamic gamma-ray emissions are common in tropical thunderclouds

M Marisaldi; N Østgaard; A Mezentsev; T Lang; J E Grove; D Shy; G M Heymsfield; P Krehbiel; R J Thomas; M Stanley; D Sarria; C Schultz; R Blakeslee; M G Quick; H Christian; I Adams; R Kroodsma; N Lehtinen; K Ullaland; S Yang; B Hasan Qureshi; J Søndergaard; B Husa; D Walker; M Bateman; D Mach; S Cummer; M Pazos; Y Pu; P Bitzer; M Fullekrug; M Cohen; J Montanya; C Younes; O van der Velde; J A Roncancio; J A Lopez; M Urbani; A Santos

doi:10.1038/s41586-024-07936-6

Highly dynamic gamma-ray emissions are common in tropical thunderclouds

Nature. 2024 Oct;634(8032):57-60. doi: 10.1038/s41586-024-07936-6. Epub 2024 Oct 2.

Authors

M Marisaldi^{1

2}, N Østgaard³, A Mezentsev⁴, T Lang⁵, J E Grove⁶, D Shy⁶, G M Heymsfield⁷, P Krehbiel⁸, R J Thomas⁸, M Stanley⁸, D Sarria⁹, C Schultz⁵, R Blakeslee⁵, M G Quick⁵, H Christian¹⁰, I Adams⁷, R Kroodsma⁷, N Lehtinen⁹, K Ullaland⁹, S Yang⁹, B Hasan Qureshi⁹, J Søndergaard⁹, B Husa⁹, D Walker¹⁰, M Bateman¹⁰, D Mach¹¹, S Cummer¹², M Pazos¹³, Y Pu¹², P Bitzer¹⁰, M Fullekrug¹⁴, M Cohen¹⁵, J Montanya¹⁶, C Younes¹⁷, O van der Velde¹⁶, J A Roncancio¹⁶, J A Lopez¹⁶, M Urbani¹⁶, A Santos¹⁷

Affiliations

¹ Department of Physics and Technology, University of Bergen, Bergen, Norway. [email protected].
² Astrophysics and Space Science Observatory of Bologna, National Institute for Astrophysics, Bologna, Italy. [email protected].
³ Department of Physics and Technology, University of Bergen, Bergen, Norway. [email protected].
⁴ Department of Physics and Technology, University of Bergen, Bergen, Norway. [email protected].
⁵ NASA Marshall Space Flight Center, Huntsville, AL, USA.
⁶ U.S. Naval Research Laboratory, Washington, DC, USA.
⁷ NASA Goddard Space Flight Center, Greenbelt, MD, USA.
⁸ New Mexico Institute of Mining and Technology, NM, Socorro, USA.
⁹ Department of Physics and Technology, University of Bergen, Bergen, Norway.
¹⁰ Department of Atmospheric Science, Earth System Science Center, University of Alabama in Huntsville, Huntsville, AL, USA.
¹¹ Universities Space Research Association, Huntsville, AL, USA.
¹² Duke University, Durham, NC, USA.
¹³ Instituto de Ciencias de la Atmósfera y Cambio Climático, National Autonomous University of Mexico (UNAM), Mexico City, Mexico.
¹⁴ University of Bath, Bath, UK.
¹⁵ Georgia Institute of Technology, Atlanta, GA, USA.
¹⁶ Polytechnic University of Catalonia, Barcelona, Spain.
¹⁷ Universidad Nacional de Colombia, Bogotá, Colombia.

PMID: 39358522
DOI: 10.1038/s41586-024-07936-6

Abstract

Thunderstorms emit fluxes of gamma rays known as gamma-ray glows^1,2, sporadically observed by aircraft^1,3-7, balloons^8-11 and from the ground^12-18. Observations report increased gamma-ray emissions by tens of percent up to two orders of magnitude above the background, sometimes abruptly terminated by lightning discharges^1,3-5. Glows are produced by the acceleration of energetic electrons in high-electric-field regions within thunderclouds⁸ and contribute to charge dissipation³. Glows had been considered as quasi-stationary phenomena^3,5,12, with durations up to a few tens of seconds and spatial scales up to 10-20 km. However, no measurements of the full extension in space and time of a gamma-ray-glow region and their occurring frequency have been reported so far. Here we show that tropical thunderclouds over ocean and coastal regions commonly emit gamma rays for hours over areas up to a few thousand square kilometres. Emission is associated with deep convective cores; it is not uniform and continuous but shows characteristic timescales of 1-10 s and even subsecond for individual glows. The dynamics of gamma-glowing thunderclouds strongly contradicts the quasi-stationary picture of glows and instead resembles that of a huge gamma-glowing 'boiling pot' in both pattern and behaviour.