Determining Electric Fields in Thunderclouds With the Radiotelescope LOFAR. Issue 8 (22nd April 2020)

• Record Type: Journal Article
• Authors: Trinh, T. N. G.; Scholten, O.; Buitink, S.; Ebert, U.; Hare, B. M.; Krehbiel, P. R.; Leijnse, H.; Bonardi, A.; Corstanje, A.; Falcke, H.; Huege, T.; Hörandel, J. R.; Krampah, G. K.; Mitra, P.; Mulrey, K.; Nelles, A.; Pandya, H.; Rachen, J. P.; Rossetto, L.; Rutjes, C.; ter Veen, S.; Winchen, T.
• Is Part Of: Journal of geophysical research. Volume 125:Issue 8(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-04-22
• Subjects: Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2019JD031433
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: An analysis is presented of electric fields in thunderclouds using a recently proposed method based on measuring radio emission from extensive air shower events during thunderstorm conditions. This method can be regarded as a tomography of thunderclouds using cosmic rays as probes. The data cover the period from December 2011 till August 2014. We have developed an improved fitting procedure to be able to analyze the data. Our measurements show evidence for the main negative‐charge layer near the −10° isotherm. This we have seen for a winter as well as for a summer cloud where multiple events pass through the same cloud and also the vertical component of the electric field could be reconstructed. On the day of measurement of some cosmic‐ray events showing evidence for strong fields, no lightning activity was detected within 100 km distance. For the winter events, the top heights were between 5 and 6 km, while in the summer, typical top heights of 9 km were seen. Large horizontal components in excess of 70 kV/m of the electric fields are observed in the middle and top layers. Key Points: Routine nonintrusive determination of atmospheric electric fields can be done from the radio footprint of cosmic‐ray air showers at LOFAR Large components of the electric fields are measured in clouds with appreciable radar reflectivity as well as without lightning activity Finding the main negative‐charge layer near the −10 isotherm for the cases where the 3‐D field was reconstructed agrees with literature