Physics & Astronomy Department
Rice University
( a m s 7 @ r i c e . e d u )
GEM 2014
Student tutorial
Image Courtesy of NASA/SOHO

 Systems science fundamentals
 What are the methodologies behind system science?
 Understanding geospace as a complex system
 Which regions of geospace constitute the system?
 How can system science be applied to geospace modeling?
 What methods will be used in Geospace Systems Science (GSS)?
 Major goals of GSS Focus Group
 What practical utility will come from GSS research?
 Focus group details
 Who’s coordinating
 Session schedule
 Future Goals
6/15/2014 GEM Student Tutorial Day 2

 Systems science is the interdisciplinary study of complex systems and their interactions
 Two properties of systems science to focus on
 System-level thinking: employing a broad range of expertise to uncover underlying system interactions
 Investigation of collective dynamical system behavior using complex systems analysis techniques
 Statistical mechanics of complex systems
 Data analysis tools
 Characterization of systems in terms of indices
 Systems science has well established methods and is used in many natural and social sciences as well as engineering applications
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 System dynamics:
 Understanding behavior of complex systems over time
 Internal feedback loops
 Characteristic time delays in system components
 Simple systems combine in non-linear ways
 Causal loop diagrams
 Used to visualize how variables in a system are related
 Positive causal links change together (+)
 Negative causal links change oppositely (-)
 Classic example is the
Adoption model
 Two kinds of loops:
Reinforcing and Balancing
-
Potential adopters
B
Market saturation
Adoption rate
+ +
R
“Word of mouth”
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+
Adopters
4

 Time lags are also included in causal loop diagrams
Avg. Maternal Age Life
Expectancy
+
Births R
Population
+ -
B
+
Deaths
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 Can be extended to encompass an arbitrarily large scope of systems
Expats
Avg. Maternal Age Life
Expectancy
+
+ +
Births R
Population X
+ -
B Deaths
Population Y
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+
Immigrants
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 Now that we have a way of organizing system variables, how do we describe their dynamics?
 System is represented as an element of a state space
 Degrees of freedom are reduced as much as possible, retaining the variables relevant to the phenomenology being studied
 This description yields a time dependent state vector that evolves through the state space, akin to Hamiltonian evolution
 Key characteristic of many system theoretical methods is the use of a geometrical interpretation
 Once this is all formalized, we study the statistical properties of the state
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 The magnetosphere-ionosphere system is complex and highly coupled
 Many processes act in tandem across interconnected regions
 Distinct systems already identified and well studied by GEM researchers
 Coupled solar-wind ionosphere-magnetosphere system:
 Driven convection
 Plasma inflow and outflow
 Ionospheric outflow
 Flux transport processes
 Wave-particle interactions
 Etc.
6/15/2014 GEM Student Tutorial Day 8

 Solar wind drives ionosphere and magnetosphere
 Ionosphere drives the magnetosphere
 Magnetosphere drives the ionosphere
Plasma outflow
+ R + M-I coupling
FACs
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+
Reconnection
Rate
GEM Student Tutorial Day 9

 How many more systems are involved?
+
Cold plasma interferes with reconnection
B
Plasma outflow
+ R + M-I coupling
FACs
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+
Reconnection
Rate
GEM Student Tutorial Day 10

 Plasmasphere has several systems science characteristics
 A) Cold plasma outflow from the ionosphere accumulates when solar wind coupling is low
 B) When solar-wind coupling increases some of the plasma can be transported to the dayside boundary (drainage plume)
 Influx of cold plasma mass loads the solar wind reconnection site, reducing the reconnection rate
(Borovsky et al., 2013)
6/15/2014 GEM Student Tutorial Day
Borovsky (2014)
11

 Plasmasphere has several systems science characteristics
 The process effectively forms a negative feedback loop in the driving of the system
 The stronger the driving, the more plasma is fed into the reconnection site
 Strength of feedback depends on the time history of the magnetosphere (time lag)
6/15/2014 GEM Student Tutorial Day
Borovsky (2014)
12

 Examples of systems science approaches:
 Multifractal behavior of dissipation in the magnetotail has been studied using the AL index
(Valdivia et al., 2013)
 Plasma displays multiscale dynamics, phase transitions, turbulence, etc.
 Complex system dynamics
 ULF indices are correlated with solar wind variables, geomagnetic indices, and other multispacecraft measurements
(Borovsky & Denton, 2014)
 Canonical Correlation Analysis (CCA) is used to correlate relativistic electron flux with time integrals of solar wind parameters and geomagnetic indices
 A review of systems theory in space physics: (Vassiliadis, 2006)
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 Advance the study of system interactions in the underlying geospace phenomena
 Identify geomagnetic systems that play a role in the solar wind driven magnetosphere
 Spearhead research on key system-level questions involving those systems
 This will take some getting used to for the GEM community; it requires us to think differently
 Recent progress in radiation belt physics has shown system -level thinking can yield insight
 Additional systems characteristics of geospace need to be addressed:
 Polar-cap potential saturation
 Substorm expansion-recovery cycle
 Scale dependence on flow structures and entropy bubbles, etc.
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 Evaluate and incorporate systems -science methodologies into
GEM research
 Application of systems science methods has mostly been limited to:
 Geomagnetic indices
 Auroral images
 Magnetotail activations
 Focus group will be a demonstration project for the value of new analysis tools
 System science methodologies are evolving rapidly and there exists a large tool set ready to utilize
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 Develop analysis tools for characterization of processes and events in observations and simulations
 These will include algorithms for analyzing statistical mechanics of complex systems using established systems science methodologies adapted to geospace science
 Focus will be on:
 Multiscale interactions of velocity, electric/magnetic field
 Transient events
 Transitions in unstable magnetic configurations
 Nonlinear correlations between interacting regions
 Studying correlation of indices using CCA
 These tools will aid forecasting ability of global simulation models
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 Identification of dynamic couplings, time lags, and feedback processes
 New indices characterizing the state of the M -I system
 Data analysis guidelines and libraries of analysis codes
 Validation of multiscale performance for computational models of the magnetosphere
 Journal special issue on GSS
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 GSS Discussion Session: Wednesday 10:30-12:15
 “Timescales, Time Lags, and Feedback Loops in the Magnetosphere -
Ionosphere System”
 Audience discussions
 GSS Discussion Session: Wednesday 1:00 - 5:00
 “Long Running Measurements of the State of the System: What Can
Be Done?”
 Audience discussions
 GSS Planning Session: Thursday 10:30 - 12:15
 Systems Topics; Systems-Science Methodologies; Data Analysis Tools
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 Joint Session with Storm-Time Inner Magnetosphere: Monday
3:30 - 5:00
 “The Physics of Shielding”
 Joint Session with Magnetosheath: Thursday 1:30 - 3:00
 “The Origins of the Non-Adiabatic Heating from the Magnetosheath into the Magnetosphere”
 Future joint sessions are expected over the 5 year term from
2014 to 2018
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Joe Borovsky
(jborovsky@spacescience.org)
Bill Lotko
(William.Lotko@dartmouth.edu)
6/15/2014
Vadim Uritsky
(vadim.uritsky@nasa.gov)
GEM Student Tutorial Day
Juan Valdivia
(alejo@macul.ciencias.uchile.cl)
20

 Coordinators with CEDAR:
Aaron Ridley
(ridley@umich.edu)
Josh Semeter
(jls@bu.edu)
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 Geospace has been i dent ified as a c omplex sy stem
 Non-linear, chaotic motion
 Feedback loops
 Coupling mechanisms
 Transient events
 Diverse phenomenology
 Two m ai n t hem es fo r t he GS S Fo c us Gro up:
 Systems thinking: Asking systems level questions to account for the connectedness of different parts of geospace
 Synthesis of GSS tools and techniques: Using methods to study the behavior of the magnetosphere without preconceptions from a physics standpoint
 Inter disciplinar y approac h i deal fo r a c o mmunity as di ver se as GE M r esearc her s
 Additional collaboration with ongoing GEM focus groups, with CEDAR, and with SHINE will take place in the future
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 If you’re interested please participate in the focus group sessions!
 Any questions?
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• Borovs k y, J. E., (2014), Feedbac k of the Magnetosp he re , Scienc e 7March 2014: 1086 -1087, doi:10.1126/ s c ie n ce .1 25 05 90
• Borovs k y, J. E., and M. H. Denton (2014 ), Explorin g the cross correlat ion s and autocorr ela ti on s of the ULF indices and incorporat ing the ULF indices into the system s science of the solar wind-dri ve n magnetosph e re , J. Geophys . Res. Space Physic s , 119, doi:10.1002/2 01 4 J A0 19 87 6
• Borovs k y, J. E., M. H. Denton, R. E. Denton, V. K. Jordanov a , and J. Krall (2013), Estimatin g the effects of ionospher i c plasma on solar wind/magnet o sp he re coupling viamass loading of dayside reconne cti on : Ion -plasm a- s h ee t oxygen, plasmasph er i c drainage plumes, and the plasma cloak, J.
Geophys . Res. Space Physic s , 118, 5695 –5719, doi:10.1002 /j gr a. 50 527
• Valdivia, J.A., Rogan, J., Munoz, V., Toledo, B.A., Stepanov a, M.(2013), The Magnetosp he re as a
Complex System, Adv. Space Res. ,51, 1934, doi: 10.1016/j.a s r.2 01 2. 04 .0 04
• Vassiliadi s , D. (2006), System s Theory for Geospace Plasma Dynamic s , Rev. Geophys. , 44, RG2002, doi:10.1029/ 20 04 R G0 001 61
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