Fwd: VERSIM Journal Club meeting on January 7
Jonathan
From: František Němec <frantis...@mff.cuni.cz>
Date: Tue, Dec 16, 2025 at 9:40 AM
Subject: VERSIM Journal Club meeting on January 7
To:
Dear colleagues,
it is my pleasure to forward a message from our Journal Club organizers regarding the meeting scheduled for January 7:
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Dear all,
We would like to invite you to the first VERSIM x GEM Journal Club meeting on January 7 at 5 PM UTC (8am PST/11am EST/6pm CET).
We are delighted to welcome Clare Watt, a senior researcher from Northumbria University, who will present her recent paper entitled "Occurrence Rates and Variability of Whistler-Mode Waves in the Plasma Trough".
The club welcomes anyone and everyone who is interested, but we particularly encourage ECRs to come along and join in! The aim of the club is to give junior researchers the opportunity to discuss different topics with international colleagues, so the sessions will be friendly, interactive and take a 'no question too silly' approach 🙂
Best wishes,
Rachel, Mirek, Jodie, Yang, Harriet and Suhail
Zoom link: https://bas-ac-uk.zoom.us/j/91489047120
Title: Occurrence Rates and Variability of Whistler-Mode Waves in the Plasma Trough
Watt et al., JGR 2025
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025JA034061
Speaker intro and paper abstract: As part of a large team, I recently published a paper on whistler-mode waves in Earth’s inner magnetosphere. I’d like to present the work (JGR abstract follows) in the context of the research project that funded the work, ongoing collaborations and history of some of the ideas that went into the paper.
Numerical models of energetic electron behaviour in the outer radiation belt require descriptions of the wave-particle interactions across the inner magnetosphere. Quasilinear diffusion coefficients describe gyro-resonant wave-particle interactions over large time- and length-scales but these must be constrained by observations to construct realistic radiation belt models. Recent work indicates the importance of identifying and including realistic spatiotemporal variation of diffusion coefficients. In this paper, we study the spatiotemporal variability of whistler-mode waves outside the plasmasphere, typically referred to as whistler-mode chorus. We separately consider the probability of (a) parts of the model domain being outside the plasmasphere, and (b) the probability of detecting wave activity should that part of the model domain be outside the plasmasphere. We discover that the spatiotemporal variability of whistler-mode waves significantly differs across the model domain; we propose that wave power variability in short wave intervals (5 min) is a useful characteristic to distinguish between two types of whistler-mode waves, especially where their frequency ranges overlap. Our novel spatiotemporal variability analysis indicates that low variability waves are dayside exohiss whose typically high occurrence rate (~0.8) decreases with substorm activity, and high variability waves are sporadic post-midnight/dawn sector substorm-driven chorus with a typical occurrence rate of 0.2. Further, although previous studies often combine the occurrence rates and wave characteristics into climatological averages of chorus wave power, this study highlights the importance of separating the study of occurrence rates and power of the waves, since each can have a different relationship with driving factors.
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F.