2010 Summer Workshop

GEM will be holding its annual summer workshop June 21-26, 2009 at the Snowmass Conference Center in Snowmass, Colorado. Pre-registration can be made at the GEM Workshop Web Site by June 5, 2009 (and online registration is open to June 14, 2009). The GEM Workshop Web Site also provides the workshop agenda.

The following GEM sessions are calling for presentations. Poster titles must be submitted to the workshop website no later than Friday, June 12.

(Note: In the e-mail addresses below the symbol @ is replaced by " [at] ".)

GGCM Metrics and Validation

Conveners: Aaron Ridley <ridley [at] umich.edu> and Masha Kuznetsova <Maria.M.Kuznetsova [at] nasa.gov>

The GGCM Metrics and Validation Focus Group would like to invite modelers to participate in a model comparison. The goal of this comparison is to examine how the different models handle basic solar wind and interplanetary magnetic field coupling with the magnetosphere. We invite modelers to bring simulation results in which the following conditions are simulated:

0. Zero dipole tilt.

1. Constant Pedersen conductances in the ionosphere of 5 mho. Zero Hall conductance. This condition is to simplify things, since everyone has a different implementation of the aurora. We need to discuss how to do a more realistic conductance, but have everyone do the same thing. We will discuss this at GEM.

2. Solar wind density is constant at 5/cc. Temperature is constant at 100,000 K. Vx is constant at -400 km/s, while Vy and Vz = 0.

3. The IMF starts at Bz=-5 nT, By=Bx=0.0. And varies as the following:

yyyy mm dd hh mm ss Bx By Bz

2000 03 21 00 00 00 0.0 0.0 -5.0

2000 03 21 02 00 00 0.0 0.0 -5.0

2000 03 21 02 10 00 0.0 0.0 -10.0

2000 03 21 04 00 00 0.0 0.0 -10.0

2000 03 21 04 10 00 0.0 0.0 -20.0

2000 03 21 06 00 00 0.0 0.0 -20.0

2000 03 21 06 10 00 0.0 0.0 -30.0

2000 03 21 08 00 00 0.0 0.0 -30.0

2000 03 21 08 10 00 0.0 0.0 -40.0

2000 03 21 10 00 00 0.0 0.0 -40.0

2000 03 21 10 10 00 0.0 0.0 -50.0

2000 03 21 12 00 00 0.0 0.0 -50.0

We would like to examine:

1. The ionospheric potential patterns and the cross polar cap potential. Please bring plots of the CPCP versus time for the entire time period.

2. The mapping of currents from the ionosphere to the magnetosphere (and beyond, as some see it.)

3. The development of the ring current. Please bring plots of Dst (if you can calculate Dst).

4. The structure of the magnetosphere, including:

(a) the position of the magnetopause and bow shock - please bring plots of the magnetopause location and bowshock location versus time;

(b) the length of the tail - please bring plots of the location of the last closed field-line (in the magnetosphere) versus time; and

(c) the shape of the magnetosphere - please bring plots of the magnetospheric current (Jy), plotting from X=~-100->~32; z=~-50->~50 at times just before the IMF Bz changes orientation (i.e., 1:45, 3:45, 5:45, 7:45, 9:45, 11:45).

We are more than willing to consider other models, rather than just global MHD simulations. For example, empirical models could be utilized. Ring current models could also be utilized (one of the interesting issues that is being discussed is whether there is saturation of the inner magnetosphere when the outer magnetosphere is saturated).

We would also like to discuss varying different parameters, if other are interested. We will discuss this further at GEM.

Aaron Ridley and Masha Kuznetsova

GGCM Modules and Methods

Conveners: John Dorelli <john.dorelli [at] nasa.gov>

The GGCM Methods and Modules Focus group would like to invite participants to two sessions to be held at the summer GEM workshop in Snowmass June 21-26. Both sessions will be held Wednesday, June 24:

Session 1 (10:30 am): What role does electron dissipation play in open boundary condition simulations of magnetic reconnection?

In this session, we would like to continue where we left off last year, addressing the following issues:

1. What is the role of secondary magnetic islands? Are they an irrelevant by-product, or do they play an essential role in determining the aspect ratio of the dissipation region?

2. What limits the aspect ratio of the electron dissipation region?

3. How does the reconnection rate scale with dissipation scale parameters (e.g., resistivity or electron mass) in simulations (electron MHD, Hall MHD, hybrid, fully kinetic)?

Session 2 (1:30 pm): How do we accurately model magnetospheric reconnection on a global scale?

Topics for this session include:

1. How does the physics of reconnection depend on the ad hoc resistivity model used in global MHD codes? In particular, how does reconnection scale with resistivity in the high Lundquist number limit? What is the effect of numerical resistivity? Can we reproduce Petschek reconnection by localizing the plasma resistivity? What is the effect of current dependent resistivity?

2. How does dayside magnetopause reconnection work in global MHD codes? Is reconnection locally controlled or externally driven? Does the Cassak- Shay formula apply to the dayside magnetopause?

3. What is the status of global Hall MHD modeling? What are the most robust numerical approaches? What are the new results coming from the latest generation of global Hall MHD magnetosphere codes?

4. What is the status of other non-MHD approaches to global magnetosphere modeling (e.g., global hybrid codes)? Are there any new ideas on the horizon?

If you are interested in participating in either of these sessions, please email one of the focus group co-chairs:

john.dorelli [at] nasa.gov or brian.sullivan [at] unh.edu.

Bow Shock Phenomena and their Magnetospheric Impacts

Conveners: N. Omidi <omidi [at] solanasci.com>, D. Sibeck <david.g.sibeck [at] nasa.gov>

During the 2009 GEM Summer workshop at Snowmass Colorado, a session on the bow shock and its magnetospheric impacts will be held on Monday June 22nd. This marks the last year of the Bow Shock Focus Group and in addition to discussion of recent observations, modeling, and theory of the bow shock and related processes in the foreshock and the magnetosheath we will discuss future plans. In particular, N. Omidi will provide a summary of accomplishments and current status and D. Sibeck will discuss future missions followed by solicitation and discussion of ideas about future directions and plans.

Those who are interested and wish to show a few relevant slides are invited to contact the conveners:

omidi [at] solanasci.com, David.G.Sibeck [at] nasa.gov.

For updated information please see http://www.cpe.vt.edu/gem/index.html .

Plasma Entry and Tranport into and within the Magnetotail (PET)

Conveners: Antonius Otto <ao [at] how.gi.alaska.edu>, Jay R. Johnson <jrj [at] pppl.gov>, and Simon Wing <Simon.Wing [at] jhuapl.edu>

We would like to invite contributions to the PET focus group at the upcoming GEM workshop in Snowmass on June 21-26, 2009. The sessions will be held in a workshop (NOT AGU) style in which each speaker will be allotted time for a 2-3 slides, in order to ensure enough time for discussion. In order to encourage this, at least one of the slides should deal with unresolved issues. Speakers are encouraged to end the presentation with outstanding questions rather than a summary of what has/have been accomplished. It is expected that there will be three sessions: (1) Plasma entry into the Magnetosphere; (2) Plasma transport in the plasma sheet; and (3) M-I coupling and magnetotail transport. Sessions 1 and 2 have been tentatively scheduled on Jun 22 Tues afternoon while session 3 on Jun 23 Wed afternoon (See http://www.cpe.vt.edu/gem/index.html for the definitive schedule). If you have not already done so, please send the title(s) and session(s) of your contribution(s) to us at your earliest convenience at the email addresses listed below.

The following lists a brief description of these three sessions.

Plasma Entry into the Magnetosphere

The session invites contributions on (a) morphology (plasma properties, time scales, dawn dusk-asymmetry etc.) of plasma entry at the magnetospheric boundaries, (b) mechanisms, models, and observation specific for northward IMF, (c) mechanism and physics for southward IMF, and (d) entry rates and physics that processes the newly entering plasma (modification of distribution functions, local entropy, fluxtube entropy,..)

Plasma Transport in the Plasmasheet

This session focuses on the topics of (a) convective vs turbulent transport for northward and southward IMF, (b) constraints to convection (entropy, boundary conditions), (c) mapping of convection to the ionosphere, observations, ionospheric influence on convection or turbulence, (d) mechanisms and related observations for convection and turbulence in the plasma sheet (recovery phase, bursty bulk flows; steady magnetospheric convection, etc.).

M-I Coupling and Magnetotail Transport

The session invites contributions on (a) the morphology of ion outflow (Fluxes, outflow locations, concentrations and distribution in the plasma sheet), (b) time scales of ion outflow, (c) solar wind dependence, (d) heating of the cold ionospheric material, (e) ionospheric influence on transport in the magnetosphere.

Dayside Magnetopause Reconnection

Conveners: Jean Berchem <jberchem [at] igpp.ucla.edu>, Nick Omidi <omidi [at] solanasci.com>

We are soliciting contributions to the Dayside Magnetopause Reconnection session that will be held at the upcoming GEM workshop in Snowmass on June 21-26, 2009.

The session will bring together people interested in the occurrence of magnetic reconnection at the dayside magnetopause. Given the wide range of scales involved in reconnection processes, the discussion will address both local and global aspects through a variety of modeling techniques including full particle, hybrid, multi-fluid and MHD simulations, as well as in-situ and ground-based observations. Our main goals this year will be to summarize recent progress and to focus on outstanding questions. Since the session will be held in a workshop style, each speaker is encouraged to present only a few slides to ensure enough time for discussion.

To facilitate scheduling, please send us a tentative title for your contribution at your earliest convenience.

Jean Berchem and Nick Omidi

Physical Processes in the Cusps: Plasma Transport and Energization

Conveners: K.J. Trattner, N. Omidi and D. Sibeck

During the 2009 Summer GEM workshop in Snowmass Colorado, a number of sessions on the physical processes in the cusp will be held. The main objective of these sessions is to utilize observations, modeling, and theory of the cusp and its role in particle acceleration and plasma transport to assess the current status of the field and forge collaborative efforts towards addressing outstanding issues in the future. Based on the topics in earlier years and the discussions during the mini-workshop held during the 2008 Fall AGU, we plan to focus on the following topics:

1. Plasma transport into the cusp.

2. Energization of ions in diamagnetic cavities.

3. Origin of waves observed in the cusp and their role in particle scattering and acceleration.

4. Interaction of FTE's with the cusp.

5. The source region of energetic ions and electrons observed in the cusp.

6. Ionospheric signatures of such processes such as Poleward Moving Auroral Forms

It is the ultimate goal of the workshop to enhance our understanding of the cusp physics, its coupling to other parts of the system such as the bow shock, magnetopause and the ionosphere and the important role it plays in dayside transport and energization. Observational and theoretical contributions to this session are hereby solicited.

Those interested in these topics are invited to attend and contribute through showing a few slides and/or participation in the discussions. Information regarding hotel reservations and travel arrangements will be posted on the GEM website (http://www.cpe.vt.edu/gem) in the near future. Those wishing to give a presentation or with questions regarding the workshop should contact the conveners:

trattner [at] mail.spasci.com, omidi [at]solanasci.com or david.g.sibeck [at] nasa.gov.

Near Earth Magnetosphere: Plasma, Fields and Coupling

Conveners: Focus Group co-chairs: Sorin Zaharia <szaharia [at] lanl.gov>, Stan Sazykin <sazykin [at] rice.edu> and Benoit Lavraud <Benoit.Lavraud [at] cesr.fr>

We would like to invite potential contributors to the Near Earth Magnetosphere: Plasma, Fields and Coupling Focus Group at the upcoming GEM Summer Workshop in Snowmass (June 21-26, 2009) to participate with modeling, theoretical and observational studies related to the topics below. Our focus group will have 3 breakout sessions on June 24 (Wed.) (for the full schedule of the workshop see http://www.ece.vt.edu/GEM-2009).

(1) Better observational knowledge/empirical models of fields and particles relevant to the near-Earth magnetosphere (including plasma sheet models to be used as input for near-Earth magnetosphere models); studies related to better knowledge of the electric fields (convection and induced) are particularly encouraged.

(2) Improvements in physics-based modeling, including coupling between different elements in the models (plasma, electric and magnetic fields), as well as inner-outer magnetosphere coupling; studies that address the effect of the above coupling on the inner magnetosphere structure/dynamics, including potential improvement of consistency with observations. A significant part of this session will be devoted to presentations of results related to the Near-Earth Magnetosphere Modeling Challenge. A description of the Challenge can also be found at the Wiki address above.

Potential contributors are urged to contact the conveners indicating their interest in participating. The sessions will be held workshop-style, with contributers encouraged to limit their number of slides to maximum 5. Please send the title of your contribution to us at the email addresses above.

Besides the 2 sessions dedicated to the topics above, a 3rd session will be devoted to refining the direction of the focus group in the future; community input is both welcome and appreciated. It is the ultimate goal of the focus group to improve physical knowledge and modeling of the near-Earth (< 10 RE) magnetosphere and its coupling with the outer magnetosphere. An outline of the major topics of interest of the focus group can be found at:

http://gem.epss.ucla.edu/mediawikiwiki/index.php/FG8._Near_Earth_Magnetosphere:_plasma%2C_fields%2C_and_coupling

Space Radiation Climatology

Conveners: Paul O'Brien (paul.obrien [at] aero.org) and Geoff Reeves (reeves [at] lanl.gov)

The Space Radiation Climatology Focus Group will host a joint meeting with the Next Generation Radiation Specifications Consortium (NGRSC). NGRSC-focused sessions will occur on Wednesday, and GEM-SRC focused sessions will occur on Thursday. See http://www.virbo.org/GEM_NGRSC_2009 for more information.

The NGRSC focus is development of radiation specification models to replace the out-of-date AE-8 and AP-8 models. The new models will improve upon AE-8 and AP-8 by being more accurate and more capable. New capabilities will include worst case environments and extended particle energy coverage. These new capabilities will help address spacecraft charging and surface dose effects which are not addressed by the current generation of specification models, except in select orbits. The workshop consisted of about 25 participants from Aerospace, Air Force Research Lab, Los Alamos National Lab, NOAA, ONERA (The French Aerospace Lab), Naval Research Lab, UCLA, and the University of Texas. Workshop presentations typically include updates on satellite particle radiation data inter-calibration, statistical models and methods, and data assimilation. Support for this effort comes from a wide array of sources, including the NRO's Proton Spectrometer Belt Research (PSBR) program and NASA's Living With a Star (LWS) program, NSF's Geospace Environment Modelling (GEM) program, and The Aerospace Corporation's IR&D program.

Wednesday AM: NGRSC Project Updates (I)

This schedule will be, if anything, more workshoppy even than GEM. We will try to allocate about 20-30 minutes of open discussion time per presentation.

Talks in this session include AE9/AP9 and LANL/DREAM project updates.

Wednesday PM1: NGRSC Project Updates (II)

Talks in this session include Aerospace and (possibly) ONERA-DESP/CRATERRE project updates

Wednesday PM2: Tools Updates et Cetera

Talks in this session include updates of IRBEM-LIB, intercalibration methodology, fast L*, and the inversion library.

Thursday AM: Recent science results from long-term simulations and data analysis

Chair: O'Brien.

Thursday our focus changes to more traditional GEM workshop questions of science, methods, and coordination of future work.

Talks scheduled so far: Weigel, Shprits, O'Brien

Thursday PM1: Implementation and methodology lessons learned

Chair: Shprits

Talks scheduled so far: Ni, Kondrashov

Thursday PM2: Data/reanalysis sharing and future plans

Chair: Weigel

Highlight: Themis SST overview by the PI, Larson.

Talks scheduled so far: Weigel, Chen, Denton

Diffuse Auroral Precipitation

Conveners: Richard Thorne <rmt [at] atmos.ucla.edu>

There will be four separate breakout sessions devoted to the Diffuse Auroral Precipitation Focus Group at the 2009 GEM workshop.

Session 1

Tu, 23 June, 1:30 p.m. - 3:00 p.m.

DAP 1: " Understanding Diffuse Auroral Structure "

Co-chaired by Marilla Samara (msamara [at] swri.edu) and Robert Michell (rmichell [at] swri.edu).

We invite contributions relating to the wide range of observable auroral structures and their classification. Diffuse aurora contains a wide range of structures including the most fine scale features. However, the mechanisms causing structure in aurora, whether discrete or diffuse, need to be defined within a larger theoretical understanding, which requires consistency in verification resulting from observations of all types of structures.

Therefore, we would like to broaden the discussion to include more than what is often deemed to be diffuse auroral structure. A main re-occurring theme is the confusion on what is actually termed diffuse aurora and most importantly how to recognize it in optical data.

Topics for discussion will include:

1. Variety of auroral structure (and characteristics) observed to date with ground imagers, satellite-borne imagers and their counterparts in the in situ particle measurements.

2. Working definition of diffuse aurora: Historical context and observations. Is it ever really structureless?

3. Current knowledge of what these diffuse auroral structures tell us about in situ and wave scattering processes (connection to the other 2 sessions). What future measurements and models will add to the current understanding?

Input on how to further shape this session is welcome and encouraged.

Session 2

Tu, 23 June, 3:30 - 5:00 p.m.

DAP 2: "The Relationship Between Diffuse Aurora and the Dynamics and Structure of the Magnetosphere"

Co-chaired by Eric Donovan (edonovan [at] ucalgary.ca) Marilia Samara and Robert Mitchell

A number of different types of aurora are classified as diffuse. These aurora are caused by a number of distinct precipitation mechanisms which sometimes overlap in space. Unlike discrete aurora, in most instances diffuse aurora is a more or less direct consequence of a process or processes in the magnetosphere, and so temporal variations of and spatial gradients in brightness are thought to convey significant information about those magnetospheric processes. Further, diffuse auroral precipitation plays some role in the loss of magnetospheric particles and in carrying large- and possibly small-scale currents, and so the diffuse aurora is important in the system-level behavior of geospace.

In this session we will be exploring the use of diffuse aurora to remote sense magnetospheric dynamics, and the role of diffuse aurora in those dynamics. We encourage contributions about (1) the physical meaning (in terms of magnetospheric dynamics and topology) of diffuse auroral boundaries and their temporal evolution, variations in brightness, as well as (2) the importance of diffuse aurora in carrying large-scale currents and magnetospheric particle loss. We encourage presentations based on observational and theoretical/modelling work. We are hoping for presentations describing work that utilizes coordinated ground-based (ASIs, induction coil & fluxgate magnetometers, riometers, ISRs, etc) and in situ (THEMIS, FAST, Polar, Geotail, LANL, etc) observations.

Topics for discussion will include

1. How is the motion of diffuse auroral structures related to magnetospheric convection?

2. The poleward boundary of the diffuse “redline” aurora has been widely used as a proxy for the open-closed field line boundary. In terms of the magnetosphere, what does the equatorward boundary of the redline aurora correspond to?

3. What is the "state of the art" in terms of using intensity ratios to infer characteristics of precipitating particles?

4. What is the instantaneous spatial extent of different types of diffuse aurora?

5. How do large-scale processes (eg., solar wind pressure pulses, ULF waves including Pi2s, etc) modulate diffuse auroral brightness?

6. How do diffuse aurora of different types relate to currents?

7. How do diffuse aurora of different relate to magnetospheric particle loss?

Session 3

Wed, 24 June, 10:30 a.m. - 12:15 p.m.

DAP 3 "Modeling Electron Scattering Rates by ECH waves and Chorus"

Co-chaired by Richard Thorne (rmt [at] atmos.ucla.edu) and Binbin Ni (bbni [at] atmos.ucla.edu).

This session will examine the global morphology, spectral properties, and variability of two classes of magnetospheric plasma waves, electrostatic electron cyclotron harmonic (ECH) and electromagnetic whistler mode chorus plasma waves, which are capable of scattering plasma sheet electrons, leading to diffuse auroral precipitation. Theoretical calculations of pitch- angle scattering rates from each class of wave will be presented to assess their potential contribution to the global pattern of diffuse auroral precipitation.

Session 4

Wed, 24 June, 1:30 – 5:00 p.m.

DAP 4: "Required Inputs for Global Modeling: Plans for 2009-2010 Activities"

Co-chaired by Margaret Chen (Margaret.W.Chen [at] aero.org) and Richard Thorne (rmt [at] atmos.ucla.edu)

In this session we will discuss how data and theoretical scattering rates can best be implemented in future models of the global distribution of diffuse auroral precipitation. We will also outline plans and objectives for the next year of the campaign.

Anyone interested in contributing to any of these sessions is encouraged to contact the relevant session chairs.

Plasmasphere-Magnetosphere Interactions

Conveners: From: Jerry Goldstein <jgoldstein [at] swri.edu> and Maria Spasojevic <mariaspasojevic [at] stanford.edu>

The 2009 GEM workshop will feature FIVE sessions for the Focus Group "Plasmasphere-Magnetosphere Interactions" (PMI). This focus group seeks to improve our understanding of the two-way coupling between the plasmasphere and magnetosphere. The PMI Focus Group website can be reached here: http://tinyurl.com/pmiFGwiki

Anyone interested in participating or contributing is encouraged to email Jerry Goldstein (jgoldstein [at] swri.edu) or Maria Spasojevic (mariaspasojevic [at] stanford.edu).

The five (5) PMI sessions to be held at the upcoming 2009 GEM:

MON 22 JUN: 10:30am - 12:15pm PMI Breakout 1A:

"Wave Growth and Propagation"

MON 22 JUN: 1:30 - 3:00pm PMI Breakout 1B:

"Plasma Influence on Wave Particle Interactions"

MON 22 JUN: 3:30 - 5:00pm PMI Breakout 2:

"Plume Transport, Evolution, and Influence"

TUE 23 JUN: 10:30am - 12:15pm PMI Breakout 3:

"Plasma Density Structure and Evolution"

THU 25 JUN: 3:30 - 5:00pm Joint PMI-CEDAR session:

"Plasmasphere, Magnetosphere, Ionosphere: Overall System Response"

More complete descriptions of these sessions are listed below under "SESSION DESCRIPTIONS".

Interested in participating or contributing? Contact:

Jerry Goldstein (jgoldstein [at] swri.edu) Maria Spasojevic (mariaspasojevic [at] stanford.edu).

SESSION DESCRIPTIONS

MON 22 JUN: 10:30am - 12:15pm PMI Breakout 1A: "Wave Growth and Propagation"

How does the evolving global distribution of cold plasma govern the growth and propagation of waves that control energetic particle distributions & dynamics?

This session focuses on the influence of ambient plasma upon how waves are produced, and how they propagate. To be examined are the conditions for growth and propagation of various waves including EMIC, whistlers (hiss, chorus), ULF, especially the influence of ambient plasma properties (such as density, composition, and spatial structure on various scale sizes).

MON 22 JUN: 1:30 - 3:00pm PMI Breakout 1B: "Plasma Influence on Wave Particle Interactions"

How do ambient plasma properties such as temperature, density, and composition influence wave particle interactions?

This session focuses on how ambient plasma influences the waves-particle interactions themselves, examining how various plasma properties (such as density, composition, and spatial structure on various scale sizes) help govern the effectiveness of various waves in changing the energy or pitch angle of energetic particles.

MON 22 JUN: 3:30 - 5:00pm PMI Breakout 2: "Plume Transport, Evolution, and Influence"

How is eroded plasmaspheric material transported, how does it evolve and influence reconnection?

This session will examine the formation, dynamics, and fate of plasmaspheric plume plasma. Specific topics to be addressed include (but are not limited to): observation or modeling of cold, dense plasma mixed with magnetospheric plasma, plume plasma at reconnection sites or on open field lines, recirculation or redistribution of cold, dense plasma into the cusp and plasmasheet.

TUE 23 JUN: 10:30am - 12:15pm PMI Breakout 3: "Plasma Density Structure and Evolution"

How do various plasma density structures originate and evolve during various phases of geomagnetic activity?

This session will focus upon outstanding questions about the dynamics of density structures in the plasmaspheric. Potential topics to be covered include, plume, fine structure & turbulence, plasma instabilities, refilling, ionosphere-thermosphere-plasmasphere interactions, and subcorotation.

THU 25 JUN: 3:30 - 5:00pm; Joint PMI-CEDAR session:

"Plasmasphere, Magnetosphere, Ionosphere: Overall System Response"

How do PMI processes influence the overall system response to storms?

This session will investigate the effects of redistribution of thermal ions (ionospheric and plasmaspheric) on the stormtime response of the overall magnetospheric system. The goal is to develop our understanding of the interaction among components of the larger system.

Contact: Jerry Goldstein (jgoldstein [at] swri.edu), Maria Spasojevic (mariaspasojevic [at] stanford.edu)

Substorm Expansion Onset: The First 10 Minutes

This is the 1st announcement of the focus group "Expansion Onset: The First 10 Minutes" for the upcoming GEM workshop in Snowmass (June 21-26, 2009; http://www.cpe.vt.edu/gem/index.html).

We will have 4 breakout sessions on June 25 (Thu) and 26(Fri) (for the current schedule of the overall workshop see http://www.ece.vt.edu/GEM-2009).

Following are four topics and primary questions we will discuss this year.

1) Onset Timing What is the time sequence of onset-related phenomena observed in space and on the ground, and what are the implications for substorm initiation?

2) M-I Coupling How does aurora evolve around substorm onsets? How are magnetospheric and ionospheric onset signatures connected in terms of auroral precipitation and currents, and what can we learn about substorm initiation from simultaneous ground-satellite observations?

3) Onset Signature Propagation How do onset-related signatures propagate in the magnetosphere? How does the uncertainty of propagation time affect our understanding of substorm initiation?

4) Mapping How does the presence and evolution of pre-onset and expansion-phase current systems affect the link between auroral and plasma sheet locations and processes?

Sessions will be scheduled based on responses to this announcement. Those who are interested in participating in the discussion are encouraged to email to Andrei Runov (arunov at igpp.ucla.edu), the session coordinator, with c.c. to other conveners.

We look forward to seeing you there.

Vassilis Angelopoulos (vassilis [at] ucla.edu)

Kazuo Shiokawa (Shiokawa [at] stelab.nagoya-u.ac.jp)

Andrei Runov (arunov [at] igpp.ucla.edu)

Shin Ohtani (ohtani [at] jhuapl.edu)

Modes of Solar Wind-Magnetosphere Energy Transfer

Convener: Larry Kepko <larry.kepko [at] unh.edu>

The Modes of Transport focus group will hold 2 breakout sessions at the upcoming GEM Workshop in Snowmass (June 21-26, 2009). Both sessions will be held on the afternoon of Tuesday, June 23. This focus group seeks to improve our knowledge of the physical mechanisms that provide for different dynamical modes of response of the magnetotail to the solar wind.

1) This first session seeks event, statistical and theoretical studies of solar wind coupling and magnetospheric response. Topics include (but are not limited to) sawtooth events, steady magnetospheric convection, and pseudo-breakups.

2) In this second session we seek to: a) Identify questions that can be addressed with global MHD simulations and b) Find events, particularly during the THEMIS era, that can be used to answer the questions developed in (a). This session will be old-school workshop format, so participants are encouraged to bring plots and data for particular events.

Interested participants should email either Larry Kepko (larry.kepko [at] unh.edu) or Bob McPherron (rmcpherron [at] igpp.ucla.edu).

Geospace System

Prospectus for a "Geospace System" Focus Group: Call for Participation

Friday, June 26, 10:30-12:15

From: Bill Lotko <wlotko [at] dartmouth.edu> and George Siscoe <siscoe [at] skynet.bu.edu>

We would like to initiate a discussion among the magnetospheric and aeronomy communities (portions, at least) on the prospect of undertaking a global, system-dynamics study of the coupled solar wind-magnetosphere-ionosphere-thermosphere system, which we identify simply as the geospace system. The suggestion responds to two circumstances: first, 50 years of magnetospheric research have shown the geospace system to be interactively coupled in multiple ways from the solar wind to the thermosphere, and second, as GEM moves in its long-range program from the 'divide-and-conquer' stage to the more challenging synthesis stage, a focus group devoted to problems of the coupled system will leverage scientific progress in each GEM research area. The magnitude of the task to comprehend the global system in its coupled complexity is almost certainly too great for a single, scientist-centered research team and probably too great for the multiple teams of a single institution. Instead it would seem to require a sustained collaborative effort by experts of manifold specialties distributed among many institutions. It might even take the combined collaboration of the GEM community and a sizable portion of the CEDAR community.

The priorities of such a focus group must be enlightened by community interest. To begin the conversation we can suggest among many possible directions several problems, each global in scope and of considerable current interest. We have asked some GEM participants to help initiate the discussion with a few slides on each problem. They include: 1) the dayside reconnection potential, its relationship to the polar cap potential, and the saturation of both at large IMF; 2) global resonance, periodicity of the magnetospheric response, and sawtooth phenomena; 3) ionospheric-magnetospheric plasma circulation, including ionospheric outflows, and its effects on plasmasheet and inner magnetospheric dynamics; and 4) prompt penetration electric fields and their relationship to the dayside ionospheric superfountain, storm enhanced density, and plasmaspheric plumes. While some aspects of these global problems can be treated as regional phenomena, differentiated by distinct physical processes, their dynamics seem to evolve as an integrated whole during extreme solar wind conditions. The geospace system thus behaves coherently across a broad spatiotemporal range, making it difficult to unravel its causal behavior by considering the response in terms of isolated elements or processes. Integration of global problems of this type into a system-dynamics picture spans the expertise of all five GEM research areas and several CEDAR working groups. We invite participation from the GEM community in deciding whether the time is right for this focus group, and, if so, how best to structure its direction.