FG: ULF Wave Modeling, Effects, and Applications

Focus Group Leaders:

• Michael Hartinger, Space Science Institute (mhartinger@spacescience.org)
• Kazue Takahashi, Applied Physics Laboratory
• Alexander Drozdov, UCLA
• Maria Usanova, University of Colorado
• Brian Kress, University of Colorado and NOAA-NCEI
• Xueling Shi, Virginia Tech

Focus Group term: 2016-2021

Join the discussion on Slack, including discussion related to the 2020 GEM and 2021 miniGEM meetings.

Science Questions

Our group aims to address the following broad science questions: What mechanisms excite ULF waves? How do ULF waves couple to the plasmasphere/ring current/radiation belt populations? What is the role of ULF waves in Magnetosphere-Ionosphere coupling?

Focus Group Proposal

ULF Wave Modeling, Effects, and Applications (UMEA) (December 2015)

ULF wave modeling challenge

One part of the ULF wave modeling challenge involves running several global MHD simulation codes with identical, idealized solar wind driving conditions (sinusoidal density variation), then comparing the resulting global ULF wave properties and discussing differences in the context of differing boundary conditions, grids, etc. More details can be found here: ULF wave modeling challenge at CCMC

Another part of the ULF wave modeling challenge involves data-model comparisons during specific events. At the 2017 GEM and mini-GEM meetings several challenge events were proposed, including two 2017 events.

We have selected the 27-28 May 2017 storm event for the ULF wave modeling challenge due to favorable solar wind coverage and availability of numerous satellites (MMS, ARASE, THEMIS, RBSP, Cluster, GOES, ...) and ground-based observations for global context and multi-point wave observations. We will be continuously updating this overview presentation with observation and modeling results. Model output and observations for the challenge event - including global densities from the NURD model - can be obtained here. If you would like to add additional observations/model output to the google drive or overview pdf, please contact the co-chairs.

CCMC has run several global MHD simulation codes using the driving conditions of the ULF wave challenge event. At the 2019 GEM meeting and future GEM/mini-GEM meetings, we plan data-model comparisons to identify where model/data don't agree and discuss these differences in the context of incorrect boundary conditions (e.g., compare model ionosphere to local PFISR-derived conductivities), missing physics, numerical dissipation, etc. Please contact CCMC/Lutz Rastaetter and model developers before using this simulation output in publications:

• Space Weather Modeling Framework simulation, IMF Bx=0 (other parameters as in event). Full 2-day event, 3D output every 15s, virtual ground magnetometer. If you haven't used CCMC visualization tools before, be aware that you shouldn’t submit multiple visualization requests at the same time, as this could crash CCMC server for these large 3D files. Instead, request a batch process or wait for the first visualization request to complete. The easiest/fastest visualization is to follow the link above and scroll down until you see the virtual ground magnetometer and satellites list. Click on the magnetometer/satellite of interest, then select which parameter(s) to display/download.

• OpenGGCM run 1 – IMF Bx = -7 nT. Smaller time range available on 28 May 0400-1000, only virtual ground magnetometer from POKR/CMO available now. Full results including virtual satellite.

• Open GGCM run 2 – IMF Bx = 0 nT (as in SWMF simulation). Same format as other OpenGGCM simulation. Full results including virtual satellite.

• LFM simulation

ULF wave HGSO event coordination

Our group is helping coordinate analysis of conjunction events for ULF wave studies, including requesting instrument operation modes favorable for ULF wave analysis.

The 2 May 2017 0400-0800 UT conjunction event includes several satellites (THEMIS, Cluster, Van Allen Probes, GOES, Geotail, FIREBIRD, METOP, POES, DMSP) in the pre-midnight sector during a conjunction with the Poker Flat Incoherent Scatter Radar and several SuperDARN radars. PFISR was operating throughout the conjunction, several SuperDARN radars were in high resolution sampling modes, and several satellites were operating in fast survey/burst mode. The conjunction is favorable for modeling and observation studies of magnetosphere-ionosphere coupling via ULF waves, wave-particle interactions, global ULF wave properties, and many other topics. This pdf summarizes preliminary results

Several web-based tools are available for identifying future conjunctions, including upcoming conjunctions between ARASE and Van Allen Probes/ground and conjunctions between SWARM/all-sky cameras.

There are also many specialized, web-based tools for ULF wave analysis (please contact FG co-chairs to add to this list):

• SuperMAG ground-based magnetometer global ULF wave plots

• CARISMA ground-based magnetometer Pc1 power spectra and Pc5 power spectra

• Augsburg College/UNH Arctic and Antarctic search coil magnetometer survey plots

• Augsburg College (hosted by ViRBO) ULF wave index

• SuperDARN wave analysis and identification of high time-resolution SuperDARN beams

• THEMIS satellite fluxgate magnetometer wave survey plots

• National Institute of Polar Research inter-hemispheric comparisons of Syowa/Iceland induction magnetometer spectra

• Inter-hemispheric comparisons during satellite conjunctions with Arctic(DTU Space)/Antarctic(Virginia Tech) magnetometers

• Meridian Scanning Photometer plots from UNIS/Kjell Henriksen Observatory, for context on open-closed boundary and ULF modulation of the aurora

Summary Reports for GEM workshops

2016 UMEA FG report

2017 UMEA FG report

2018 UMEA FG report

2019 UMEA FG report

2016 Mini-GEM schedule

UMEA will hold one session at the mini-GEM workshop: ULF wave modeling, effects and applications updates

Time: 12:00-13:30, Sunday, December 11, 2016

Location: Oregon Room, Holiday Inn Golden Gateway

Schedule:

First Half (12:00 – 12:45): 3 talks (~15 min each):

• 1. Mike Hartinger -- Overview of UMEA current activities, discussion of future plans

• 2. Lutz Rastaetter -- ULF wave modeling challenge at CCMC

• 3. Robert Rankin -- Modeling the global properties and ground-based signatures of ULF waves and wave-particle interactions

Second Half (12:45 – 13:30): (5 minutes each, 1-2 slides, order of talks may change):

• 1. Xueling Shi -- SuperDARN THEMIS Mode Data Tracker & ULF Wave Detection

• 2. Richard Denton -- Mass density inferred from Alfven wave frequencies measured by RBSP

• 3. Lars Daldorff -- ULF waves, particle transport and energization in global MHD simulations with plasmasphere

• 4. Alexander Drozdov -- Dependence of radiation belt simulations to assumed radial diffusion rates tested for two empirical models of radial transport

• 5. Bob Lysak -- Quarter Wavelength Modes

• 6. Walk-ins

2017 GEM meeting schedule

UMEA will hold four sessions session at the 2017 GEM meeting

UMEA Update and plans, general discussion of ULF wave modeling and observations: 10:30-12:15, Monday, June 19, Port VI-VIII

• 1. Michael Hartinger -- UMEA update

• 2. Toshi Nishimura -- PFISR measurements during the 2 May 2017 HGSO event

• 3. Xueling Shi -- A Survey of Ionospheric ULF Wave Signatures in SuperDARN Data: Occurrence Statistics and Driving Mechanisms

• 4. Tetsuo Motoba -- Dayside Auroral Pulsations

• 5. Brian Kress and Rob Redmon -- Newly Available GOES 8-16 Particle and Magnetic Field Measurements

• 6. Dick Wolf -- Theory of magnetospheric buoyancy waves

ULF wave interactions with the radiation belt and ring current populations: 1:30-3:00, Monday, June 19, Port VI-VIII

• 1. Rualdo Soto-Chavez -- Generation of Pc5-ULF wave by the drift-mirror instability

• 2. Zhiyang Xia -- Eigenmode analysis of compressional poloidal modes in a self-consistent magnetic field

• 3. Mark Engebretson -- Statistical study of the upper frequency cutoff of helium band EMIC waves observed by the Van Allen Probes

• 4. Alexander Drozdov -- Radial diffusion and EMIC waves in the long-term simulation and in the case study

• 5. Seth Claudepierre -- Global MHD simulations driven by idealized Alfvenic fluctuations in the solar wind

• 6. Michael Hartinger -- Radiation belt response to large scale, monochromatic ULF waves: LANL-GEO observations

ULF wave modeling, including CCMC modeling challenge, Joint with MMV: 3:30-5:00, Monday, June 19, Port VI-VIII

• 1. Lutz Rastaetter -- CCMC ULF wave modeling challenge update and challenge events

• 2. Scot Elkington -- ULF wave activity and diffusion coefficients during QARBM challenge events, Ashar F. Ali’s write-up on Event-Specific Radial Diffusion Coefficients Derived Using RBSP EMFISIS and EFW Data

• 3. Katariina Nykyri -- KHI challenge events

• 4. All -- Open Discussion of Challenge Events

• 5. Doga Ozturk -- Effects of Increased Solar Wind Dynamic Pressure on the Coupled M-I system under different IMF By

• 6. Kazue Takahashi -- Cavity mode Van Allen Probe observations

• 7. Bob Lysak -- Cavity mode models

• 8. Tom Elsden -- The Theoretical Foundation of 3D Alfven Resonances: Time Dependent Solutions

Magnetosphere-Ionosphere coupling processes associated with localized disturbances caused by dayside kinetic phenomena: Joint with “Dayside Kinetic Processes…” and “Testing proposed links…”: 3:30-5:00, Tuesday, June 20, Port VI-VIII

• 1. Peter Chi -- Magnetospheric and ionospheric responses to a localized disturbance: The macroscopic view

• 2. Hui Zhang -- Magnetospheric ULF waves generated by foreshock transients

• 3. Hui Zhang -- Modeling challenges in simulating HFA geoeffects

• 4. Boyi Wang -- Optical signatures of dayside ULF waves during magnetosheath high-speed jets

• 5. Katariina Nykyri -- The effect of magnetosheath seed spectrum on KH evolution and associated mass transport

• 6. Kyle Murphy -- A statistical study of discrete ULF wave power observed by GOES

2017 Mini-GEM schedule

UMEA will hold two sessions at the 2017 mini-GEM workshop

Time: 12:00-13:30, Sunday, December 10, 2017, Canal/50

ULF wave modeling challenges Discussion of final plans for the CCMC ULF wave modeling challenge with idealized drivers, as well as open discussion of new challenges involving data-model and model-model comparisons during specific events. Please come with 1-2 slides showing examples of such comparisons, ideas for improving ULF wave models, and/or ideas for specific modeling challenges/sessions relevant to the FG science questions.

• 1. 12:00-12:30 Overview of CCMC ULF wave modeling challenge with idealized driving conditions, description of challenge events and targets proposed during 2017 GEM meeting and November modeling telecon (Michael Hartinger, Lutz Rastaetter)
• 2. 12:30-13:30 Open discussion of challenge events and targets (Allison Jaynes, Robert Rankin), select challenge event to be analyzed at 2018 GEM

Time: 13:50-15:20, Sunday, December 10, 2017, Canal/50

Heliophysics/Geospace system observatory coordination for ULF wave studies Discussion of HGSO coordination for ULF wave studies. This includes updates on the 2 May 2017 conjunction event followed by an open discussion of conjunctions and datasets that are particularly useful for ULF wave studies, including upcoming RBSP-ERG-ground conjunctions. Please come with 1-2 slides showing examples of datasets and past/upcoming conjunctions ideal for addressing the FG science questions: What excites ULF waves? How do ULF waves couple to the plasmasphere/ring current/radiation belt populations? What is the role of ULF waves in MI coupling? We welcome discussion from both modelers and observers of the types of conjunctions and observations that are most needed to address these questions.

• 1. 13:50-14:20 Recently available datasets and conjunctions for ULF wave studies (Chih-Ping Wang, Xueling Shi, Sana Qamar, Rob Redmon)
• 2. 14:20-14:35 Updates on 2 May 2017 conjunction event (Toshi Nishimura, Michael Hartinger)
• 3. 14:35-15:20 Upcoming ARASE-RBSP conjunctions (Yoshi Miyoshi), Open Discussion of HGSO coordination for ULF wave studies (Toshi Nishimura, Kazue Takahashi)

2018 GEM meeting schedule

UMEA will hold four sessions at the 2018 GEM meeting.

ULF waves during particle injections and dipolarizations, joint with Dipolarization and Substorm FG: 10:30-12:00, Monday, June 18

• 1. Discussion of Session Topic

• 2. Bob Lysak -- Ionospheric Conductivity Effects on Pi2 Pulsations

• 3. Mike Hartinger -- Pi2 waves during an extended period with stable plasmapause location and variable geomagnetic activity

• 4. Toshi Nishimura -- Ionosphere observations of Pc5 ULF waves during 2018 HGSO conjunctions

• 5. Xueling Shi -- Long-lasting poloidal ULF waves observed by multiple satellite and SuperDARN HF radars

• 6. Jian Yang -- New RCM-I simulation results for buoyancy waves

• 7. Dick Wolf -- Theory of Buoyancy Waves

• 8. Yan Song -- What Causes the Substorm Expansion Phase and Associated ULF Waves?

Recent advances in ULF wave research: 1:30-3:00, Monday, June 18

• 1. Overview of focus group goals and recent progress

• 2. Brief ULF wave poster overviews (Tuesday posters)

• 3. Kazue Takahashi -- Observation of nightside ULF waves by RBSP and Arase

• 4. Tom Elsden -- Broadband Excitation of 3D Alfven Resonances (FLRs) in an MHD Waveguide

• 5. Boyi Wang -- 2-D structure of foreshock driven Pc5 ULF waves observed by the THEMIS satellites and South Pole imager

• 6. Xiaochen Shen -- Foreshock transient-driven ultra-low frequency (ULF) waves with dawn-dusk asymmetry of wave power

• 7. Chih-Ping Wang -- ULF waves possibly driven by tailward propagation of foreshock perturbations

• 8. Allison Jaynes -- Fast diffusion of ultra-relativistic electrons in the outer radiation belt: 17 March 2015 storm event

• 9. Rualdo Soto -- The Drift-Mirror instability in Earth's inner magnetosphere

• 10. Martin Archer/Mike Hartinger -- Results from Sonification and Citizen Science of Magnetospheric ULF waves

EMIC wave generation, propagation, and interactions: 3:30-5:00, Monday, June 18 (discussion leaders: Alexander Drozdov and Maria Usanova) Session Summary

• 1. Dedong Wang -- EMIC wave observations from Van Allen Probes and MMS

• 2. Mark Engebretson -- Van Allen Probes, and ground based magnetometer observations of EMIC waves associated with a modest interplanetary shock

• 3. Maria Usanova -- MMS Observations of Harmonic Electromagnetic Cyclotron Waves

• 4. Naritoshi Kitamura -- Direct measurements of energy transfer from hot H+ to EMIC waves by MMS

• 5. Bruce Fritz -- ELF Whistler Dependence on a Sunlit Ionosphere

• 6. Chae-Woo Jun -- EMIC waves associated with/without the injection inside/outside the plasmapause

• 7. Hyomin Kim -- Injection-associated EMIC waves

• 8. Sebastian Cervantes -- EMIC wave parameterization in radiation belt reanalysis

• 9. Maria Usanova -- Long-term correlation of EMIC wave activity and radiation belt flux variations

• 10. Alexander Drozdov -- The effects due to the EMIC waves in the VERB code modeling

ULF wave modeling challenge, joint with MMV FG: 3:30-5:00, Wednesday, June 20

• 1. Brief ULF wave poster overviews (Thursday posters)

• 2. Mike Hartinger: ULF wave modeling challenge event overview, discussion of challenge targets (continuing during session)

• 3. Mariko Teramoto: ARASE ULF wave observations during challenge event

• 4. Sam Califf: GOES-14 and 16 observations during the ULF wave challenge event, Data Discussion

• 5. Toshi Nishimura: PFISR measurements of the 27-28 May 2017 ULF waves

• 6. Dogacan Su Ozturk: The modeling study of the 27 March 2017 Event

• 7. Xiaochen Shen: GEM Challenge Event: ULF wave-related electron and proton precipitation/negative dynamic pressure pulse driven EMIC wave

• 8. Tetsuo Motoba: Auroral measurements of the 27-28 May 2017 ULF waves

• 9. Others discuss when their figures/summary plots in event overview pdf are presented…

2018 Mini-GEM schedule

UMEA will hold two sessions at the 2018 mini-GEM workshop

Time: 13:50-15:20, Sunday, December 9, 2018, Salon C

ULF modulation of the aurora, Heliophysics/Geospace system observatory coordination for ULF wave studies This session focuses on understanding a variety of mechanisms responsible for ULF modulations of the aurora. Eric Donovan will give a 30 minute invited presentation, with the rest of the session open for presentations and discussion on this topic. We welcome discussion of ULF aurora generation mechanisms and the types of conjunctions, observations, and models needed to understand the zoo of ULF auroral modulations. We also welcome discussion of upcoming observation campaigns/satellite conjunctions that would be particularly useful for ULF wave studies.

• 1. Eric Donovan
• 2. Tetsuo Motoba
• 3. Slava Pilipenko
• 4. Boyi Wang / Toshi Nishimura
• 5. Open discussion

Time: 15:30-17:00, Sunday, December 9, 2018, Salon C

ULF wave modeling challenge and research highlights The first part of the session is for updates on the idealized ULF wave modeling challenge and potential 2019 GEM sessions. The next part of the session is for observation/model presentations relevant to the 27-28 May 2017 ULF wave challenge event and final selection of the modeling challenge targets – all types of models and observations welcome. The last part of the session will be open for 1 slide ULF wave modeling and observation research highlights.

• 1. 2019 GEM session ideas (Mike Hartinger)
• 2. Idealized Modeling Challenge (Lutz Rastaetter)
• 3. ULF wave modeling challenge event updates: Rob Redmon/Sam Califf/Mike Hartinger (GOES magnetometer observations), Yoshi Miyoshi (Arase magnetic field observations), Hyomin Kim (wave-particle interaction), Dong Lin (LFM simulations)
• 4. General ULF wave modeling: Yaireska Collado-Vega (vortex identification/surface waves), Alex Degeling (ULF wave radiation belt interactions)
• 5. Research highlights (1-slide): Rualdo Soto (Van Allen Probes and Cluster satellites’ observations of Pc 5 (mHz) magnetic pulsations), Xueling Shi (SuperDARN ULF waves), Martin Archer (magnetopause surface eigenmodes), Martin Archer (sonification)

2019 GEM meeting schedule

UMEA will hold six sessions at the 2019 GEM meeting, four joint with other focus groups.

Recent advances in ULF wave research: Modeling: 3:30-5:00, Monday, June 24 New Mexico room, joint with MMV. Discussion of advances in ULF wave research, with focus on modeling and modeling challenges (e.g., boundary conditions, grid resolution, missing physics). This includes models of the effects of ULF waves on inner magnetosphere dynamics and wave-particle interactions. We particularly encourage presentations focused on the ULF wave modeling challenge, including data-model comparisons for the 27-28 May 2017 challenge event.

• Mike Hartinger, FG updates
• Jesper Gjerloev, SuperMAG ULF updates
• Tetsuo Motoba, High-time resolution SuperMAG ULF data products
• Lutz Rastaetter, ULF wave modeling challenge
• Maulik Patel, MHD test particle simulations of the 16 July 2017 shock compression of the dayside magnetopause
• Bob McPherron, Pi 2 pulsations during the storm of May 27-29 2017, The Statistics of Pi 2 Pulsation Occurrence during a Major Magnetic Storm
• Dong Lin, LFM simulations of surface waves during challenge event

The ULF response to dayside transients with different temporal/spatial scales: 10:30-12:00, Wednesday, June 26 Santa Fe room, discussion leader: Tom Elsden, joint with Dayside Kinetics and IHMIC. Dayside transient phenomena associated with kinetic scale processes cause a variety of ULF wave behaviour in the magnetosphere and further, contribute to significant magnetospheric asymmetries. The aim of this session is to bring together the expertise of the three focus groups listed above, to answer outstanding questions at the overlap of these disciplines. It is hoped that such a discussion should prove fruitful enough to generate a JGR commentary paper in this area. With this in mind, speakers in this session are encouraged to give their views as to the current state of the subject area, and how outstanding problems may be addressed in the future.

• Tom Elsden - Session introduction and goals
• Ferdinand Plaschke (invited) - An overview of dayside transients causing ULF waves
• Tom Elsden - 3D ULF wave modeling with MHD
• Boyi Wang - The role of magnetosheath high-speed jets in triggering magnetospheric Pc5 ULF waves
• Bob Lysak - Ionospheric asymmetries and quarter-wave modes
• Xueling Shi - Conjugate Observations of ULF Waves during an Extended Period of Radial IMF
• Michael Hartinger - Localized magnetopause surface wave activity and modeling challenges
• Discussion

ULF wave modeling challenges associated with Magnetosphere-Ionosphere-Thermosphere Coupling: 3:30-5:00, Wednesday, June 26 Lumpkins Ballroon South, joint with IEMIT, discussion leader Doga Ozturk. ULF waves play important roles in M-I-T coupling, driving current systems that can lead to I-T system heating and geomagnetically induced currents. This session aims to bring together researchers from the ULF wave and M-I-T coupling research communities to discuss challenges associated with realistically modeling M-I-T coupling processes associated with these waves. The session will begin with a discussion of the ULF wave challenge event; comparisons between modeled / observed (PFISR) conductivities and modeled/observed ULF wave properties will be presented, and the community will be invited to discuss explanations for model/observation differences. The rest of the session is open for short presentations on ULF wave modeling challenges related to M-I-T coupling, including topics such as specifying conductivity and effect of conductivity on wave properties, effect of ionospheric boundary conditions in global simulations, boundary conditions and feedback between magnetosphere and ionosphere, capturing role of waves in ionospheric-thermospheric heating.

1. (Invited) Boyi Wang: Ionospheric modulation by Pc5 ULF waves and wave structure detected by PFISR
2. (Invited) Xiaojia Zhang / Anton Artemyev: ULF modulation of VLF waves and precipitation
3. Doga Ozturk: Update from GEM/CEDAR joint session, ULF Wave activity and Meso-Scale electric field variability at high-latitude I-T system
4. Anatoly Streltsov: ULF waves generated by the MI interactions near the plasmapause
5. Mergen Alimaganbetov: ULF waves observed in space and on the ground at high and low latitudes
6. Mark Engebretson: Multi-Instrument Observations of Nighttime Impulsive Magnetic Events
7. Bob Lysak: Modeling ionospheric conductance and ground magnetic fields
8. Yan Song: ULF wave, M-I coupling and Auroral formation.

EMIC waves: 10:30-12:00, Thursday, June 27 New Mexico room, joint with Radiation Belt. The generation mechanisms of Electromagnetic Ion Cyclotron (EMIC) waves, their effects on energetic electrons and ions, and their propagation through the magnetosphere-ionosphere system are challenging topics that involve multiple GEM research areas. Despite several years of observations and improved global wave statistics, there are many unresolved questions that limit further investigation, modeling and prediction of dynamical processes in the inner magnetosphere involving EMIC waves. Hence, we invite short presentations that discuss recent findings in different areas of EMIC wave research and identify observations/models most needed to address unresolved questions.

• Robert Allen, Outer magnetospheric EMIC wave source regions characterized by Cluster
• Sarah Vines, EMIC waves in the outer magnetosphere: Observations of an off-equator source region
• Justin Lee, EMIC wave observations by MMS
• Chao Yue, The relationship between EMIC wave properties and proton distributions based on Van Allen Probes observations
• Kristine Sigsbee, Simultaneous EMIC Wave Observations During a Van Allen Probes Conjunction
• Hyomin Kim, Observations of Particle Loss due to Injection-Associated EMIC Waves
• Yuri Shprits, Dips in PSD and how they are related to EMIC wave scattering
• Richard Denton, Electromagnetic ion cyclotron waves in the dipole magnetosphere and pitch angle scattering of sub-MeV relativistic electrons by those waves
• Qianli Ma, Pitch angle scattering of radiation belt electrons due to statistical EMIC wave spectra

Recent advances in ULF wave research: Observations and HGSO coordination for ULF wave studies: 1:30-3:00, Thursday, June 27 New Mexico room. Discussion of recent advances in ULF wave research, with focus on observations and a general discussion of Heliophysics/Geospace System Observatory coordination for ULF wave studies. We particularly encourage presentations describing (1) past or upcoming satellite conjunctions, (2) new data analysis tools, and/or (3) instrumentation/operation modes of interest to the ULF wave research community.

• Seth Claudepierre/Matina Gkioulidou (invited), Van Allen Probes: End of Mission and ULF wave studies
• Tetsuo Motoba, SuperMAG ULF wave tools
• Sarah Vines, Determining EMIC wave vector properties through multi-point measurements: The wave curl analysis
• Aaron Breneman, BARREL precipitation during solar wind driven ULF wave events
• Anatoly Streltsov, Effect of the Hall conductivity on generation of ULF waves
• Mohammad Barani, Estimating the Azimuthal Mode Structure of ULF Waves Based on Multiple GOES Satellite Observations
• Kazue Takahashi, L versus time structures of ground magnetic pulsations
• Chih-Ping Wang, Earthward propagation of Pi2 waves

ULF waves driven by wave-particle interactions and instabilities: 3:30-5:00, Thursday, June 27 Lumpkins Ballroon South, discussion leaders: Xueling Shi and Hyomin Kim. Many ULF wave modes are closely related to instabilities and wave-particle interactions inside the magnetosphere: poloidal mode waves associated with particle injections, mirror/drift-mirror modes, buoyancy waves… These waves are often discussed in different contexts and in different GEM sessions. In addition, there have been relatively few studies of modeling internally generated ULF waves. The purpose of this session is to bring together modelers and observers to discuss the underlying processes that drive/damp these waves, their impact(s) on the M-I system (ring current, radiation belt, ionosphere,…), and the models/observations needed to better understand wave dynamics.

• Xuzhi Zhou (invited), Acceleration of relativistic electrons by global-scale ULF waves
• Tomotsugu Yamakawa (invited), Simulation of the excitation of storm-time Pc5 ULF waves by ring current ions based on the drift-kinetic model
• Frank Toffoletto, Normal Mode Analysis of Buoyancy Waves
• Peter Chi, Observations of High-m Poloidal Waves along Magnetospheric Field Lines
• Mike Hartinger, Observations of wave-particle interactions using MagEIS ultra-high resolution energy channels
• Jiang Liu, Ultralow Frequency Waves Deep Inside the Inner Magnetosphere Driven by Dipolarizing Flux Bundles, and their interaction with electrons
• Kyle Murphy, TBD

2019 Mini-GEM schedule

UMEA will hold one session at the 2019 mini-GEM workshop

Time: 15:30-17:00, Sunday, December 8, 2019, Nevada Room

ULF wave modeling challenge event, HGSO coordination, and research highlights The first part of the session is for updates on the ULF wave modeling challenge and potential 2020 GEM sessions. The next part of the session is open for ULF wave research presentations discussing the ULF wave modeling challenge event or current/upcoming observation campaigns that are particularly useful for ULF wave studies. The last part of the session will be open for 1 slide ULF wave research highlights.

• Mike Hartinger, UMEA updates and proposed sessions for 2020 GEM workshop
• Dong Lin, LFM Simulations of ULF wave modeling challenge event
• Mohammad Barani, High-fidelity ULF wave azimuthal mode number structure estimation using MMS magnetometer observations, link to related presentation on YouTube
• Chih-Ping Wang, Inward propagation of Pi2 wave from plasma sheet to inner magnetosphere: THEMIS-GOES conjunctions
• Walk-ins

2020 VGEM schedule

UMEA will hold two sessions at the 2020 Virtual GEM workshop

Time: 13:00-14:30 US Eastern Time, Wednesday, July 22, 2020

ULF wave modeling challenge event (Hosted by Xueling Shi) The first part of the session is for updates on research related to the challenge event (27-29 May 2017 storm): All modeling and observation talks welcome as long as they're related to this event. The last part of the session will be for short research highlights and oral summaries of posters.

• Mike Hartinger (10 minutes), 2020 UMEA updates and overview of challenge event
• Simone Di Matteo (15 minutes), On some features characterizing the plasmasphere–magnetosphere–ionosphere system during the geomagnetic storm of 27 May 2017
• Bob McPherron (15 minutes), ULF wave activity at synchronous orbit during the May 27-29, 2017 Magnetic storm
• Boyi Wang (15 minutes), Ionospheric modulation by storm-time Pc5 ULF waves and wave structure detected by PFISR-THEMIS conjunctions
• Lutz Rastaetter (15 minutes), Idealized ULF wave modeling challenge: high-resolution runs
• Mark Engebretson (5 minutes), Nighttime magnetic perturbation events observed in Arctic Canada: Superposed epoch analysis
• Jinxing Li (5 minutes), Electron microinjections in association with compressional ULF waves: MMS observations
• Xiaojia Zhang (5 minutes), Spreading of Magnetopause-Generated Ultra-Low-Frequency Perturbations and the Associated Whistler Modulation

Time: 15:00-16:30 US Eastern Time, Wednesday, July 22, 2020

ULF wave research highlights These will be contributed talks with priority given to graduate students and postdocs. The rationale is that virtual GEM will not provide the same type of networking opportunities as in-person GEM, and we'd like to balance this somewhat by giving more opportunities to students/postdocs to present their work on ULF waves.

All presentations are 10 minutes including discussion:

• Rachel Rice, Characteristics of Kelvin-Helmholtz Waves as Observed by MMS
• Dong Lin, Idealized ULF wave simulations with GAMERA-RCM model
• Boyi Wang, The interaction between ions and the ULF waves driven by a foreshock transient
• Jayashree Bulusu, Investigation of Pi2s during super quiet conditions from low and mid-latitudes
• Changzhi Zhai, High-m Poloidal ULF Wave Signatures in GPS TEC Data
• Simone Di Matteo, Power Spectral Density Background Estimate and Signal Detection via the Multitaper Method
• Yixin Hao, Simultaneous observations of localized and global drift resonance
• Mohammad Barani, Effects of realistic mode number structure on radial diffusion estimation

2021 Virtual Mini-GEM schedule

UMEA will hold one session at the Virtual Mini-GEM Worskhop.

Time: 12:00-14:00 US Eastern Time, Friday, January 22, 2021

ULF wave modeling challenge event, planning for 2021 GEM meeting, and research highlights The first part of the session is for updates on the ULF wave modeling challenge event, including an invited talk by Naoko Takahashi. The next part of the session will be for open discussion on potential 2021 GEM sessions. The final part of the session will be open for ULF wave research highlights.

• Mike Hartinger, Brief Introduction to Challenge event
• Naoko Takahashi, Relative contribution of ULF waves and whistler-mode chorus to the radiation belt variation during May 2017 storm
• Ian Kelley, GPS TEC response during the ULF wave challenge event
• Mike Hartinger, ULF wave geoelectric fields during the challenge event
• All, Planning for 2021 GEM sessions
• Bob Lysak, FLRs in Jupiter's magnetosphere
• Toshi Nishimura, Upcoming conjunctions for ULF wave studies
• Toshi Nishimura, PFISR and all-sky imager observations of Pc5 ULF waves during substorms
• Francesco Lena, Detection of Hertz Frequency Multiharmonic Field Line Resonances at Low-L (L=1.1–1.5) During Van Allen Probe Perigee Passes

2021 VGEM schedule

UMEA will lead four sessions at the 2021 Virtual GEM workshop.

Time: 13:00-14:30 US Eastern Time, Monday, July 26, 2021

Recent Advances in ULF Wave Research This session will start with a short update on the ULF wave modeling challenge. The rest of the session will be for recent advances in ULF wave research, with priority given to presentations (1) with data or modeling results related to the challenge event (27-28 May 2017) or (2) discussions of ULF wave data-model comparisons.

• Mark Engebretson, Pc1 waves / MMS k-vector technique
• Michelle Salzano, IPDP-Pi1B - modeling drift shell splitting
• Yangyang Shen, Tens to hundreds of keV electron precipitation driven by kinetic Alfven waves during an electron injection
• Chih-Ping Wang, Statistical results for Pi2 waves associated with the plasma sheet BBFs observed by THEMIS-RBSP pair with RBSP inside or outside the plasmasphere
• Tom Elsden, Modelling the Varying Location of Field Line Resonances During Geomagnetic Storms
• Denny Oliveira, Factors controlling shock-induced magnetospheric ULF waves
• Short Oral Summaries of Posters
• Open Discussion

Time: 15:00-16:30 US Eastern Time, Monday, July 26, 2021

The Future of ULF Wave Research This session will begin with a review of the ULF wave FG’s original goals, research topics covered in the last 5 years and related activities, and unresolved questions and research objectives. The remainder of the session is open for 1-2 slide presentations on major unresolved questions in ULF wave research. We particularly encourage presentations (1) exploring topics that could be addressed by current/future GEM FG or decadal survey white paper, (2) highlighting major questions or obstacles preventing progress in ULF wave research (e.g., missing data in a critical region, missing theory/modeling component), (3) discuss how ULF wave researchers can best take advantage of future satellite missions, ground-based infrastructure, computing advances/big data/AI, and modeling/theory advances.

• Mike Hartinger, Retrospective on the ULF wave focus group
• Martin Archer, Surface Waves
• Tom Elsden, 3D FLRs
• Solene Lejosne, Wave-Particle Interactions
• Ayomide Olabode and Michelle Salzano, Ground Magnetic Perturbations
• Xueling Shi, Applications of TEC observations
• Open discussion, walk-in presentations welcome

Time: 13:00-14:30 US Eastern Time, Tuesday, July 27, 2021

ULF Wave M-I Coupling Processes This session is joint with the IEMIT FG. The session will begin with a review of the role of ULF waves on M-I coupling. The remainder of the session is open for 5-min presentations on ULF wave topics related to M-I coupling, e.g., auroral acceleration, particle precipitation, geomagnetic perturbations, GICs, etc. More questions and discussions will be left to the end.

• Hui Zhang, Role of ULF waves in M-I coupling
• Chaosong Huang, Global Pc5 pulsations
• Tetsuo Motoba, Daytime Pc5 Diffuse Auroral Pulsations and Their Association With Outer Magnetospheric ULF Waves
• Anton Artemyev, ULF driven precipitations as observed by ELFIN
• Mark Engebretson, Magnetic perturbation events related to GICs
• Denny Oliveira, IP shock impact angle control of local intense dB/dt variations during substorm
• Xueling Shi, Sources of Intense Geoelectric Fields in the United States

Time: 13:00-14:30 US Eastern Time, Friday, July 30, 2021

Coupling Between ULF Waves and Cold Plasma This session is joint with the Cold Plasma FG. The session will begin with a review of mechanisms that couple cold plasma populations to ULF waves by Richard Denton. The remainder of the session is for contributed presentations (likely 2-3 slides) describing (1) recent advances in our understanding of cold plasma interactions with ULF waves and (2) outstanding questions that could be discussed in future cold plasma FG sessions.

• Richard Denton
• Alex Degeling
• Eun Hwa Kim
• Bob Lysak
• Qiugang Zong
• Mike Hartinger