F. J. Pérez-Invernón

Mesospheric optical signatures of possible lightning on Venus

This work was supported by the Spanish Ministry of Science and Innovation, MINECO under projects ESP2013-48032-C5-5-R, FIS2014-61774-EXP, and ESP2015-69909-C5-2-R and by the EU through the FEDER program. F.J.P.I. acknowledges a MINECO predoctoral contract, code BES-2014-069567. A.L. acknowledges support by a Ramon y Cajal contract, code RYC-2011-07801.

On the electrostatic field created at ground level by a halo

This work was supported by the Spanish Ministry of Science and Innovation, MINECO under projects ESP2013-48032-C5-5-R, FIS2014-61774-EXP, and ESP2015-69909-C5-2-R and by the EU through the FEDER program. F.J.P.I. acknowledges a MINECO predoctoral contract, code BES-2014-069567. A.L. acknowledges support by a Ramon y Cajal contract, code RYC-2011-07801

Three-dimensional modeling of lightning-induced electromagnetic pulses on Venus, Jupiter, and Saturn

While lightning activity in Venus is still controversial, its existence in Jupiter and Saturn was first detected by the Voyager missions and later on confirmed by Cassini and New Horizons optical recordings in the case of Jupiter, and recently by Cassini on Saturn in 2009. Based on a recently developed 3D model we investigate the influence of lightning-emitted electromagnetic pulses (EMP) on the upper atmosphere of Venus, Saturn and Jupiter. We explore how different lightning properties such as total energy released and orientation (vertical, horizontal, oblique) can produce mesospheric transient optical emissions of different shapes, sizes and intensities. Moreover, we show that the relatively strong background magnetic field of Saturn can enhance the lightning-induced quasi-electrostatic and inductive electric field components above 1000 km of altitude producing stronger transient optical emissions that could be detected from orbital probes.

Modeling the Chemical Impact and the Optical Emissions Produced by Lightning‐Induced Electromagnetic Fields in the Upper Atmosphere: The case of Halos and Elves Triggered by Different Lightning Discharges

This work was supported by the Spanish Ministry of Science and Innovation, MINECO, under projects ESP2015-69909-C5-2-R and ESP2017-86263-C4-4-R and by the EU through the H2020 Science and Innovation with Thunderstorms (SAINT) project (Ref. 722337) and the FEDER program. F.J.P.I. acknowledges a PhD research contract, code BES-2014-069567. A.L. was supported by the European Research Council (ERC) under the European Unions H2020 program/ERC grant agreement 681257. The simulation data and plot codes presented here are available from figshare repository at https://figshare.com/s/f1c9f6c7 bc728d6669dd. Alternatively, requests for the data and codes used to generate or displayed in figures, graphs, plots, or tables are also available after a request is made to the authors F.J.P.I. (fjpi@iaa.es), A. L. (aluque@iaa.es), or F. J. G.V. (vazquez@iaa.es).

Spectral Characteristics of VLF Sferics Associated With RHESSI TGFs

Abstract We compared the modeled energy spectral density of very low frequency (VLF) radio emissions from terrestrial gamma ray flashes (TGFs) with the energy spectral density of VLF radio sferics recorded by Duke VLF receiver simultaneously with those TGFs. In total, six events with world wide lightning location network (WWLLN) defined locations were analyzed to exhibit a good fit between the modeled and observed energy spectral densities. In VLF range the energy spectral density of the TGF source current moment is found to be dominated by the contribution of secondary low‐energy electrons and independent of the relativistic electrons which play their role in low‐frequency (LF) range. Additional spectral modulation by the multiplicity of TGF peaks was found and demonstrated a good fit for two TGFs whose VLF sferics consist of two overlapping pulses each. The number of seeding pulses in TGF defines the spectral shape in VLF range, which allows to retrieve this number from VLF sferics, assuming they were radiated by TGFs. For two events it was found that the number of seeding pulses is small, of the order of 10. For the rest of the events the lower boundary of the number of seeding pulses was found to be between 10 to 103.

Whistler Wave Propagation Through the Ionosphere of Venus

We investigate the attenuation of whistler waves generated by hypotetical venusian lightning occurring at the altitude of the cloud layer under different ionospheric conditions. We use the Stanford Full Wave Method (FWM) for stratified media of (?Lehtinen2008/JGR) to model wave propagation through the ionosphere of Venus. This method calculates the electromagnetic field created by an arbitrary source in a plane-stratified medium (i.e. uniform in the horizontal direction). We see that the existence of holes in electronic densities and the magnetic field configuration caused by solar wind play an important role in the propagation of electromagnetic waves through the venusian ionosphere.