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8
Report of the Panel on Atmosphere-Ionosphere-Magnetosphere Interactions
8.1 SUMMARY OF AIMI SCIENCE PRIORITIES AND
IMPERATIVES FOR THE 2013-2022 DECADE
During the past decade, a variety of observations and modeling efforts led us to the current
appreciation of the atmosphere-ionosphere-magnetosphere (AIM) system as a complex and active
element of space weather, and as a region where important science questions with broad applicability
across our solar system can be answered. Earth’s space environment, or Geospace, is unique in many
ways: the interconnected behavior of the plasma and neutral gas in the AIM system, the strong signature
of lower atmospheric conditions in space, and the development of massive plasma structures with
embedded variability at multiple scales, are just a few examples. Pursuit of understanding energy transfer
and physical manifestations in near-Earth space has and will continue to offer insights into fundamental
processes that occur at other planets and bodies in our solar system and indeed throughout the universe.
Beyond an understanding of our own home in space and universal planetary processes, developing a
capability for predicting conditions in geospace is the most important practical outcome to emerge from
scientific investigation of the AIM system. This is because all of the space-based assets for observation
and communication of human activities operate in geospace and contend with all the hazards and
unpredictability that this energetic, non-linear system produces.
This chapter is devoted to articulating the AIMI panel’s science goals and aspirations for the
following decade, and to suggesting an implementation strategy to achieve this vision. It presents an
interlinked and achievable research program to address the most compelling science questions in the field.
Below is an “executive summary” of the panel’s science priorities, imperatives, and recommendations to
the steering committee for the 2013-2022 decade.
The three major AIMI science priorities for the 2013-2022 decade are:
AIMI Science Priority 1: Determine how the ionosphere-thermosphere system regulates the flow
of solar energy throughout geospace.
AIMI Science Priority 2: Understand how tropospheric weather influences space weather.
AIMI Science Priority 3: Understand the plasma-neutral coupling processes that give rise to local,
regional, and global-scale structures and dynamics in the AIM system.
These priorities emerge from the five AIM science goals described in the section entitled
“Science Goals and Priorities for the 2013-2022 Decade,” and the panel’s assessment of the resources
required to address them, and leads to the following imperatives:
AIMI Imperative 1: Close a critical gap in the NASA Heliophysics Observatory with a mission
that determines how solar energy drives ionospheric-thermospheric variability, and that lays the
foundation for a space weather prediction capability.
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AIMI Imperative 2: Provide a broad and robust range of space-based, suborbital, and ground-
based capabilities that enable frequent measurements of the AIM system from a variety of
platforms, categories of cost, and levels of risk.
AIMI Imperative 3: Integrate data from a diverse set of observations across a range of scales,
coordinated with theory and modeling efforts, to develop a comprehensive understanding of
plasma-neutral coupling processes and the theoretical underpinning for space weather prediction.
AIMI Imperative 4: Conduct a theory and modeling program that incorporates accumulated
understanding and extends the legacy of observations into physics based models that are utilized
for new scientific insight and operational specification and forecast capabilities.
These imperatives represent a balanced strategy for addressing the panel’s priority science and
are not listed in priority order. The requirements underlying the imperatives span five categories:
spaceflight missions; explorers, suborbital, and other platforms; ground-based facilities; theory and
modeling; and enabling capabilities. Priorities within each of these categories are summarized in turn
below.
8.1.1 Spaceflight Missions
No new NASA missions are under development or are currently planned for the future that
address any of the AIM science priorities articulated above. This deficiency represents an acute
imbalance in the study of the Sun-Earth system that impedes scientists’ ability to resolve complex AIM
system behavior that impacts geospace dynamics and the operation of ground- and space-based assets on
which society depends. A critical AIMI imperative therefore is that a mission addressing the response of
the ionosphere-thermosphere (IT) system to variable forcing be put forth as the highest priority of the
Solar and Space Physics Decadal Survey. The most compelling AIM science questions of the coming
decade are best addressed with a Global Dynamics Constellation (GDC) mission nominally consisting of
6 identical satellites, in high-latitude equally spaced circular orbits, with the goal of understanding how
winds, temperature, composition, chemistry, charged particles and electric fields interact to regulate the
observed global response of the IT. This mission will also provide new insights into the IT response to
dynamical coupling with the lower atmosphere. If this mission must be delayed at all due to budgetary
constraints, then a revitalized Heliophysics instrument and technology development program must
support GDC’s implementation later in this decade. In that case, then the AIMI panel suggests that the
DYNAMIC mission be put forth as the decadal survey’s number-one priority for the 2013-2022 decade.
DYNAMIC is a pair of satellites in LEO orbits separated by 6 hours of local time, carrying the
instruments to measure the critical energy inputs to the AIMI system from the spectrum of waves entering
from below. While the primary focus of DYNAMIC is to understand how lower atmosphere variability
drives IT variability, it will also measure important properties of the IT response to variable
magnetospheric forcing.
Additional NASA missions that address another high-priority science challenge of the next
decade—understanding the two-way interaction between the ionosphere-thermosphere and the
magnetosphere—are also described in this document. These missions and associated science are also
potential candidates for the Explorer program.
8.1.2 Explorers, Suborbital, and Other Platforms
The relative proximity of the AIM system makes it amenable to observational strategies involving
a wide variety of platforms. This attribute is a significant strength in crafting a program that is responsive
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to budgetary realities and to the changing climate of programmatic risk factors. The following AIMI
panel priorities maintain this crucial flexibility:
Explorer Program Enhancement (highest priority). Enhance the Heliophysics Explorer line to
support a broad range of science missions that can address important AIMI science challenges.
Mission classes should range from a Tiny Explorer that takes advantage of miniaturized sensors
and alternative platforms and hosting opportunities, up to a medium Explorer that could address
multiple science challenges for the decade.
Constellations of Satellites. Develop the means to effectively and efficiently implement
constellation missions, including proactive development of small satellite capabilities and
miniaturized sensors, and pursuit of cost-effective alternatives such as commercial constellations.
Suborbital Research. Maintain a strong suborbital research program. Continue development of
observatory-class capabilities such as a High Altitude Sounding Rocket and long-duration
balloons, and expand funding for science payload development for these platforms.
Strategic Hosted Payloads. Develop a strategic capability to make global-scale AIMI imaging
measurements from host spacecraft, notably those in HEO and GEO orbits, as is currently done in
support of solar (GOES SXT) and magnetospheric (TWINS, GOES, LANL) research.
8.1.3 Ground-Based Facilities
New ground-based instrumentation and associated research programs can also address an array of
AIMI science questions in this decade. These facilities will play a major role in an overall strategy to
understand the origins of plasma-neutral structures over local (tens to hundreds of kilometers), regional
(hundreds to thousands of kilometers) and global scales (thousands to tens of thousands of kilometers), as
well as the interactions between structures over these different scales. In particular, several prospective
facilities are particularly compelling in advancing of AIMI science priorities:
Autonomous American Sector Network. Develop, deploy, and operate a network of 40 or more
autonomous observing stations extending from pole to pole through the (north and south)
American longitudinal sector. The network nodes should be populated with heterogeneous
instrumentation capable of measuring such parameters as winds, temperatures, emissions,
scintillations, and plasma parameters for study of a variety of local and regional ionosphere-
thermosphere phenomena over extended latitudinal ranges.
Whole-Atmosphere Lidar Observatory. Create and operate a lidar observatory capable of
measuring gravity waves, tides, wave-wave and wave-mean flow interactions, and wave
dissipation and vertical coupling processes from the stratosphere to 200 km. Co-location with a
research facility such as an Incoherent Scatter Radar (ISR) installation would enable study of a
number of local-scale plasma-neutral interactions relevant to space weather.
NSF Medium-scale Research Facility (MRF) Program. The above facilities are candidates for
support by the NSF Geospace Program and would require that a Medium-scale (~$40 million to
$50 million) Research Facility (MRF) funding program be instituted at NSF to fill the gap
between the Major Research Instrumentation (MRI, <$4 million) and Major Research Equipment
and Facilities Construction (MREFC, >$100 million) programs.
Southern-Hemisphere Expansion of Incoherent Scatter Radar (ISR) Network. In addition to the
two projects listed above, expansion of the now proven Advanced Modular Incoherent Scatter
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Radar (AMISR) technology to southern polar latitudes (i.e., Antarctica) would provide for the
first-ever view of detailed ionosphere processes in the southern polar hemisphere, thus
contributing a critical missing component to the Heliophysics Observatory.
Ionospheric Modification Facilities. Fully realize the potential of ionospheric modification
techniques through co-location of modern heating facilities with a full complement of diagnostic
instruments including incoherent scatter radars. This requires coordination between NSF and
DOD agencies in the planning and operation of existing and future ionospheric modification
facilities.
8.1.4 Theory and Modeling
Cross-scale coupling processes are intrinsic to AIM system behavior. Phenomena and processes
that are highly structured in space and time (e.g., wave dissipation, turbulence, electric field fluctuations)
can produce effects (e.g., wind circulations, chemical transport, Joule heating, respectively) over much
larger scales. At the same time, larger-scale phenomena create local conditions that can either promote or
suppress development of rapidly changing structures at small spatial scales (e.g., instabilities and
turbulence). The observational strategies presented in this report place high priority on understanding how
local, regional, and global-scale phenomena couple to produce observed responses across scales. These
strategies call for complementary development of theory and numerical modeling capabilities that enable
comprehensive treatment of cross-scale coupling processes, together with new data synthesis technologies
that combine multiple, hetero-scale data sources into a common framework for understanding critical
aspects of the AIM system.
Therefore, to support the synergistic program of space-based investigations and ground-based
facilities, the AIMI panel has the following priorities regarding theory and modeling:
Model Development. Comprehensive models of the AIM system would benefit from the
development of embedded grid and/or nested model capabilities, and use them to understand the
interactions between local- and regional-scale phenomena within the context of global AIM
system evolution.
Theory. Complementary theoretical work would enhance the understanding of the physics of
various-scale structures and the self-consistent interactions between them.
Assimilative Capabilities. Comprehensive models of the AIM system would benefit from
developing assimilative capabilities and serve as the first genre of space weather prediction
models.
Further priorities concerning theory and modeling are provide under “enabling capabilities”
below.
8.1.5 Enabling Capabilities
The missions and initiatives described above require additional capabilities and infrastructure that
enable cheaper and more frequent measurements of the AIM system, that transform measurements into
scientific results, that maintain the health of the scientific community, and that serve the needs of 21st-
century society. These enabling capabilities (i.e., working group priorities) fall into the following
categories:
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• Innovations: Technology, Instruments and Data Systems,
• Theory, Modeling and Data Exploitation,
• Research to Operations-Operations to Research, and
• Workforce and Education.
The panel’s priorities in these areas are detailed in the section entitled “Theory and Modeling” of
this chapter.
The panel also considered the motivations underlying the study of the AIM system (in the section
entitled “Motivations for Study of Atmosphere-Ionosphere-Magnetosphere (AIM) Interactions”), and then
articulates recent accomplishments (in the section entitled “Significant Accomplishments of the Previous
Decade”), science goals (the section entitled “Science Goals and Priorities for the 2013-2022 Decade”),
and implementation strategies (the section entitled “Implementation Strategies and Enabling
Capabilities”) in some detail.
8.2 MOTIVATIONS FOR STUDY OF ATMOSPHERE-IONOSPHERE-MAGNETOSPHERE
INTERACTIONS
Unlike other planets in our solar system, the presence of water, oxygen and moderate
temperatures creates an environment on Earth that is habitable for humans. And, while radiation from the
Sun’s light is responsible for warming the surface to relatively comfortable temperatures, its other
energetic outputs produce conditions and events that can be disruptive and even catastrophic to our
society. Extreme weather events close to the surface, such as
hurricanes and tornadoes, are part of life on Earth. But our planet
is also embedded in the streaming plasma and magnetic field of
the Sun’s outer corona (see Figure 8.1), which can lead to weather
in space with similarly disastrous consequences. Although
Earth’s magnetic field serves as a protective cocoon that is
difficult for the Sun’s plasma and magnetic field to penetrate,
transmission of a few percent of this energy into near-Earth space
can produce large effects. Reconnection between the magnetic
fields of the Sun and Earth cause electric fields, currents, and
energetic particles to be created. Energetic particles serve the
double-edged role of creating magnificent auroral displays while at the same time penetrating satellite
electronics and solar cells and disrupting or sometimes terminating their operation. Electric currents
flowing through the auroral ionosphere heat the atmosphere and produce global changes in upper
atmosphere density that make it difficult to predict the future locations of satellites and potential
collisions between them. Electrical connections between the near-Earth space environment and the
ionosphere can also disrupt the operation of communications and navigation systems, cell phones, and
even induce dangerous levels of currents in the U.S. power distribution system. Energetic particle
precipitation into the upper atmosphere can also initiate a chain of events that lead to massive depletions
of stratospheric ozone in the polar regions. These are only a few of the consequences that emerge from a
complex web of interactions occurring within this active region called geospace, and that motivate us to
Understand our Home in the Solar System (M1) and to Predict the Changing Space Environment and it
Societal Impact (M2).
This chapter is devoted to the region of geospace where atmosphere-ionosphere-magnetosphere
interactions occur. It extends from roughly the top of the stratosphere (ca 50 km) to several thousand
kilometers, where the presence of the neutral atmosphere ceases to exert any significant control over the
system. This region of geospace possesses several distinguishing characteristics that define it as a domain
for compelling scientific inquiry as well as meeting the needs of our 21st -century society, and that
warrant the attention of this decadal survey. First, in terms of its connections with the Sun, the
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heliosphere and magnetosphere, this region serves as a “final link” in the transfer of energy within the
solar-terrestrial chain. The primary drivers for variability in the region consist of direct solar energy in the
form of EUV and UV radiation, solar energy transformed into the charged particles and fields that
permeate the magnetosphere, and solar-driven waves propagating upward from the lower atmosphere
(Figure 8.1).
FIGURE 8.1 A depiction of the atmosphere-ionosphere-magnetosphere (AIM) system and the major
processes that occur within that system. Absorption of short-wavelength solar radiation accounts for a
large fraction of the heat input. Energetic particles, mostly from the magnetosphere, enhance the
ionospheric conductance at high latitudes, and modify the electrical currents that flow between the
ionosphere and magnetosphere. Magnetospheric convection imposes electric fields that drive currents in
the lower part of the ionosphere and set the ionospheric plasma into motion at higher altitudes, with a
portion escaping into geospace and beyond. These injections of energy drive a global thermospheric
circulation that redistributes heat and molecular species upwelling from the heated regions, and also
excites a spectrum of waves that redistribute energy both locally and globally. Planetary waves, tides,
and gravity waves propagate upward from the lower atmosphere, deposit momentum into the mean
circulation, and generate electric fields via the dynamo mechanism in the lower ionosphere. Dynamo
electric fields are also created by disturbance winds. Neutral winds and electric fields from these
combined sources redistribute plasma over local, regional, and global scales and sometimes create
conditions for instability and production of smaller-scale structures in neutral and plasma components of
the system. SOURCE: Courtesy of Joe Grebowsky, NASA GSFC.
Responses to these drivers are determined by interacting dynamical, chemical and electrodynamic
processes that occur over a wide range of spatial and temporal scales, and moreover are strongly
influenced by the presence of a strong magnetic field. Often these processes involve nonlinearity and
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feedback, and it thus evident that this complex system can often exhibit emergent behavior.1 In fact,
scientific investigations of this geospace region resolving and interpreting the system’s response to
variable forcing, and ultimately unraveling the complex chains of events leading to the observed,
emergent behavior. (Several examples of emergent behavior will be provided in this chapter.) Given this
complexity, one can appreciate the difficulties of predicting the variability of neutral and plasma densities
to the accuracies required to support orbital, reentry, communications and navigation systems in
operational settings. Thus, as this chapter unfolds, it will become evident that the study of atmosphere-
ionosphere-magnetosphere interactions presents challenging scientific problems that are fundamental in
understanding planetary atmospheres and exospheres, and that underlie the ability to predict
environmental conditions that serve operational needs. In addition, the processes that are studied in this
context can often be translated to other planetary bodies, and in this way geospace serves as a local
laboratory to Reveal and Study Universal Physical Processes (M3).
The following section of this chapter summarizes the main scientific achievements of the last
decade, reflecting back on the recommendations of the previous decadal survey. This lays the foundation
for the subsequent section, which sets forth the science agenda for 2013-2022. The section after that
addresses the various assets, resources and strategies needed to advance our science most productively,
and presents a prioritized program for doing so.
8.3 SIGNIFICANT ACCOMPLISHMENTS OF THE PREVIOUS DECADE
Understanding of atmosphere-ionosphere-magnetosphere (AIM) interactions have advanced
through a number of vigorous programs, ranging from national, international, and multiagency programs
to smaller scale programs. Examples of programs that have helped shape the research landscape over the
past decade are NASA’s Living with a Star (LWS) and Heliophysics Geospace Science programs, the
NASA TIMED Solar Terrestrial Probe, the NASA IMAGE mid-explorer (MIDEX) mission, the NASA
FAST Small Explorer (SMEX) mission, the NASA THEMIS MIDEX mission, the NASA AIM SMEX
mission, and the U.S. Air Force (USAF) C/NOFS mission; the NASA Sounding Rocket Program; the
National Space Weather Program; the NSF-sponsored SHINE, GEM, CEDAR, and small satellite
programs and their international counterparts; the NSF major research initiative (MRI) and science and
technology centers (STC); numerous DOD activities; International satellite programs, such as CHAMP,
GRACE, and COSMIC; and International science programs, such as CAWSES. These various programs
have supported satellite and ground-based instruments and the related data analysis, theory and modeling
efforts. Research models and data assimilation schemes have advanced operational space weather
prediction and created new models of the Sun-Earth system using a systemic and holistic perspective:
Center for Integrated Space Weather Modeling (CISM), Community Coordinated Modeling Center
(CCMC), NCAR Whole Atmosphere Community Climate Model (WACCM) development, and solar
wind/magnetosphere models coupled with ionosphere/thermosphere global circulation models. Through
these targeted programs and the critically important base programs funded by NSF, NASA, NOAA, and
the DOD, important scientific progress has been made, helping us to clarify needs and identify priorities
that form the basis of this panel report.
New supporting technologies, not specifically targeted for AIM research, have also significantly
contributed to the field’s advancement in the past decade. These include cyberinfrastructure, advanced
communications, improved sensors, networking technology, increases in computing power, precision
navigation systems, and small satellites. Complementing this technology growth were planned
developments in space-borne and ground-based missions, major research instrumentation and facilities
development, data assimilation schemes, and whole atmosphere model development. These technological
advancements help accelerate the scientific endeavors and enable new science areas to be investigated and
1
Emergent behavior results from the interaction of a large number of system components that could not have
been anticipated on the basis of the properties of components acting individually.
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understood. The emergence of relocatable incoherent scatter radars (ISRs) based on electronically
steerable antenna arrays is an excellent example. These NSF-supported Advanced Modular ISRs
(AMISRs) can be steered on a pulse-to-pulse basis, allowing the simultaneous acquisition of information
from multiple directions. The rapid steering capabilities of AMISR-class ISRs provide a unique
capability for supporting AIM science objectives. For instance, these instruments can be used to
construct three-dimensional views of the evolving plasma state within a volume traversed by a satellite or
rocket.
Model development has been facilitated by major advances in instrumentation and measurement
techniques, experimental facilities, and observing networks, which are starting to provide unprecedented
volumes of data on processes operating across AIM. Together with concurrent progress in computational
techniques, these advances have enabled the development of ever more sophisticated, multidimensional
models of geospace. These models, along with data assimilation schemes, offer the promise of greater
insights into the physical processes at work and improved ability to forecast disruptive events and their
potential impacts.
Development of numerical models that extend from Earth’s surface to the
thermosphere/ionosphere has made significant breakthroughs during the past decade. These whole-
atmosphere models are able to generate atmospheric disturbances, such as sudden stratospheric warmings
(SSM) and quasi-biennial oscillation (QBO) internally without having to impose artificial forcing, and to
investigate their dynamical and electrodynamical coupling to the upper atmosphere in a self-consistent
manner. Models that couple the magnetosphere and the ionosphere/thermosphere have reached the
maturity to include feedback interaction between thermospheric neutrals and magnetospheric plasmas, as
well as mass and momentum exchanges within geospace. In addition, physics-based data assimilation
models of the global ionosphere have been developed that are capable of assimilating multiple data types,
for example, to reconstruct the electron density configuration during storms. These models are now
running routinely in a test-operational mode for space weather specification.
The adoption and implementation of a systems approach is more realizable today with the rapid
expansion of multidimensional databases, increasing computational capabilities and sophistication of
numerical tools, and emergence of new sensor technologies. Complementing these technological
advancements have been new scientific discoveries that are rooted in a systems perspective of AIM
science. What has emerged from this past research is the recognition that many of the natural coupling
processes within AIM are linked through system complexity processes of feedback, nonlinearity,
instability, preconditioning, and emergent behavior. The following examples of significant
accomplishments of the previous decade reflect this overarching recognition.
8.3.1 Magnetosphere-Ionosphere Coupling
A recent discovery in AIM science comes from a fortuitous combination of new measurement
capabilities. The explosive increase in the global distribution of GPS receivers both on the ground and in
space and the flight of the NASA IMAGE mission to image Earth’s magnetosphere and ionosphere,
showed a completely new view of ionospheric/magnetospheric coupling during storms. Global GPS maps
of ionospheric density showed, for the first time, large-scale dense plumes of plasma extending from
middle latitudes to the auroral zone at the onset of magnetic storms (Figure 8.2). During such events,
plasmaspheric imaging of He+ ions by IMAGE showed corresponding structures in the inner
magnetosphere, where plasma was sheared away from the plasmasphere and advected toward the
magnetopause. The plasmaspheric structure was never expected to appear in the ionosphere, and the
discovery points to a process critical to enhancing auroral ion outflow during storms. Further research
results from NASA’s FAST and IMAGE satellites revealed that storm-enhanced ionosphere plasma feeds
outflows of ionospheric ions into a tornado-like, cusp funnel, powered by Alfvén waves generated by the
solar wind-magnetosphere interaction. Evidence is accumulating that energy in these small-scale Alfvénic
current filaments is deposited over a range of spatial and temporal scales and is converted to heat and
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momentum through ion-neutral interactions. These findings highlight the importance of feedback through
the AIM system where magnetospherically imposed electric fields redistribute ionospheric plasma,
fueling the flux of outflowing ions to the magnetosphere. The outflows, especially heavy-ion outflows,
can overwhelm reconnection mass loss in the plasma sheet and, effectively, reduce the cross polar cap
potential and the concomitant ionospheric electric fields. In some instances, emergent behavior results
whereby ~3 hour planetary-scale (sawtooth) oscillations in the magnetosphere are observed. These occur
when the M-I system is strongly driven by a steady solar wind and seem to rely on superfluent nightside
outflows of ionospheric O+.
FIGURE 8.2 Storm-enhanced plasma density (SED) signatures in total electron content (TEC) observed
on March 31, 2001. These are believed to be connected to plasmashere erosion and driven by sub-auroral
electric fields from the inner magnetosphere. SOURCE: Foster, J.C., P.J. Erickson, A.J. Coster, J.
Goldstein, and F.J. Rich, Ionospheric signatures of plasmaspheric tails, Geophys. Res. Lett. 29(13):
10.1029/2002GL015067, 2002, Copyright 2002 American Geophysical Union. Reproduced by
permission of American Geophysical Union.
8.3.2 Solar-AIM Coupling
The past decade marks the 23rd solar cycle on modern record and witnessed a number of
powerful geomagnetic storms, two separate sunspot maxima, and an extreme solar minimum providing
for the most extreme variability and conditions observed by the Heliophysics Observatory, the new and
existing facilities of NSF, NOAA, and the U.S. military research laboratories. Solar cycle 23 is the first
cycle in which a complete record of coronal mass ejections (CMEs), coronal hole distributions, and solar
wind data are all available over the whole cycle since the first detection of CMEs in the early 1970s. The
availability of simultaneous space and ground-based data covering the Sun-Earth space has made solar
cycle 23 solar storms and geomagnetic activity one of the best set of events to analyze. It has been
possible to assemble atmospheric, ionospheric, magnetospheric, interplanetary, and solar data on 88 CME
storms during solar cycle 23. Many more events of enhanced geomagnetic activity were observed during
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this cycle associated with corotating interaction regions (CIRs)/high-speed solar wind streams (HSS)
related to low heliolatitude distributions of persistent coronal holes.
A few of the CME storms were considered “great” storms that led to unexpected or emergent
behavior in the AIM system. Ionosphere observations indicated the emergence of a daytime super-
fountain effect lifting the ionosphere to new heights and increasing its total electron content by as much
as 250 percent. Also observed were very large amplitude traveling ionospheric disturbances (Figure 8.3),
new ionosphere layers, and very different behavior in equatorial plasma irregularities.
FIGURE 8.3 Illustration of Traveling Atmospheric Disturbances (TADs) seen in densities near 400 km
near local noon measured by the accelerometer on the CHAMP satellite, in connection with a
geomagnetic disturbance on day 308 of 2003. The data are obtained at nearly constant longitudes about
every 1.5 hours, i.e., the time between consecutive “passes” or “orbits” of the satellite. The disturbance
was initiated between pass 6 and 7, and takes roughly 4.5 hours to reach the equator from both
polar/auroral regions. The southward-propagating disturbance appears to pass into the Southern
Hemisphere. The behaviors of these disturbances in other local time sectors is not known, nor is it known
how dissipation of this disturbance has modified the mean state of the IT system. SOURCE: Courtesy of
Sean Bruinsma, CNES.
The atmosphere responded with dramatic changes in neutral composition, winds, temperature and
mass density. Thermosphere mass density at 400 km increased by over 400 percent during these great
storms while experiencing exceptionally fast recovery times, indicating a unique overcooling effect. The
CIR/HSS storms were predominant during the declining and minimum phase of the solar cycle producing
an entirely different response in the AIM system. Where CME storms lasted a few days and were
episodic, CIR/HSS storms lasted for more than a week and recurred for many solar rotations—in some
instances sustaining common periodicities for an entire year. This has led to the discovery in atmosphere
and ionosphere data sets of pervasive periodicities at subharmonics of the ~27-day solar rotation period
during solar cycle 23 (Figure 8.4). Unfortunately, although CHAMP, COSMIC, and ground-based
platforms provided new discoveries in terms of total neutral and plasma density responses of the AIM
system to the various solar disturbances noted above, only sparse measurements were made of the key
parameters (e.g., winds, plasma drifts, neutral and ion composition) needed to understand these responses.
It is a high-priority goal of the next decade to gain this understanding.
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FIGURE 8.4 Quasi-9-day periodicity in the thermosphere densities as a result of recurring high-speed
solar wind streams (and associated recurrent geomagnetic activity) originating from longitudinally
distributed solar coronal holes. (A) Latitude versus time variations of CHAMP neutral densities (in units
of 1012 kg/m3) during days 25-100, 2005. The solid black line denotes the Kp values, corresponding to the
right-hand scale. (B) Percent of the band-pass filter density residuals to 11-day running mean during days
25-100, 2005. The band-pass filter was centered at the period of 9 days, with half-power points at 6 and
12 days. The perturbations in Kp obtained from the same band-pass filter are superimposed in the lower
panel (dashed line, right hand scale). SOURCE: J. Lei, J.P. Thayer, J.M. Forbes, E.K. Sutton, and R.S.
Nerem (2008), Rotating solar coronal holes and periodic modulation of the upper atmosphere, Geophys.
Res. Lett. 35:L10109, doi:10.1029/2008GL033875. Copyright 2008 American Geophysical Union.
Reproduced by permission of American Geophysical Union.
8.3.3 Meteorology–AIM Coupling
One of the most exciting developments in recent years has been a new realization of the direct
and strong impact of tropospheric weather and climate on the upper atmosphere and ionosphere. The
connection has been elicited, first, from measurements of the ionospheric density near the equator by
NASA IMAGE and TIMED satellites, showing large changes in the structure of the ionosphere on
seasonal timescales. This signature has subsequently been observed in upper thermospheric composition
and temperature. The clear correspondence demonstrated in this confluence of efforts has energized the
study of atmospheric wave coupling to space plasma. Other observations and model studies have
unequivocally revealed that Earth’s ionosphere-thermosphere (IT) system owes a considerable amount of
its longitudinal, local time, seasonal-latitudinal and day-to-day variability to atmospheric waves that begin
near Earth’s surface and propagate into the upper atmosphere. Waves propagating upward from the lower
atmosphere contribute about equally to the energy transfer in the IT system as direct solar energy in the
form of EUV and UV radiation, and re-processed solar energy in the form of particles and fields from the
magnetosphere. This unexpected and new realization is important for the “space weather” of the IT
system. It is becoming increasingly clear that understanding wave driving from below is critical for
predicting large and small scale structures in the IT system, such as ionospheric scintillations important to
communication and navigation, and testing and improving models for orbit propagation and collision
warnings.
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FIGURE 8.22 Gravity wave vertical structures seen in electron densities by the Poker Flat Incoherent
Scatter Radar (PFISR) on 13 December 2006. The scale is in terms of percent perturbation relative to the
mean; maximum electron density perturbations at the lowest altitudes exceed 20 percent. These authors
attribute observed accelerations of the mean thermosphere winds to dissipation of the waves. SOURCE:
S.L. Vadas and M. Nicolls, Temporal evolution of neutral, thermospheric winds and plasma response
using PFISR measurements of gravity waves, JASTP 71:740-770, 2009.
FIGURE 8.23 Large-aperture Na atomic density lidar measurements at 60 millisecond and 15 meter
resolution showing detailed Kelvin-Helmholtz structures at the base of the layer. SOURCE: T. Pfrommer,
P. Hickson, and C.-Y. She, A large-aperture sodium fluorescence lidar with very high resolution for
mesopause dynamics and adaptive optics studies, Geophys. Res. Lett. 36:L15831,
doi:10.1029/2009GL038802, 2009. Copyright 2009 American Geophysical Union. Reproduced by
permission of American Geophysical Union.
The available laser power has also increased exponentially over the years and, when combined
with a large-aperture telescope, winds and temperatures can be retrieved well into the thermosphere using
the proven Rayleigh lidar technique. A lidar simulation based on a laser transmitter of 325 W at 750
pulses per second and an 8-m telescope can retrieve neutral temperatures at 200 km with 10 percent error
at a range resolution of 5 km with one hour integration. Obviously the temporal and spatial resolution
improves exponentially as altitude decreases leading to unprecedented measurements of neutral gas
properties in the thermosphere and mesosphere. Recent lidar developments are also providing new
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possibilities for observations in the thermosphere. A helium resonance lidar is under development to
probe the resonance structure of metastable helium in the upper atmosphere. If demonstrated, wind and
temperatures would be derivable from altitudes well above 200 km. The technological advances expected
with this program will also help lead to future developments of a lidar system in space for upper
atmosphere research.
Create and operate a lidar observatory capable of measuring gravity waves, tides, wave-wave and wave-
mean flow interactions, wave dissipation and vertical coupling processes from the stratosphere to 200
km. Co-location with a research facility such as an Incoherent Scatter Radar (ISR) installation would
enable study of a number of local-scale plasma-neutral interactions relevant to space weather.
FIGURE 8.24 Composite image showing auroral forms, F-region ion temperature, and F-region ion
flows, illustrating the local reduction in electric field in the vicinity of an auroral activation---a
consequence of the polarization response of the ionosphere to the increased conductivity produced by the
auroral precipitation. SOURCE: Semeter, J., T. W. Butler, M. Zettergren, C. J. Heinselman, and M. J.
Nicolls, Composite imaging of auroral forms and convective flows during a substorm cycle, J. Geophys.
Res., 115, A08308, doi:10.1029/2009JA014931, 2010. Copyright 2010 American Geophysical Union.
Reproduced by permission of American Geophysical Union.
8.5.3.3 The Incoherent Scatter Radar (ISR) Network
ISR is an extraordinarily powerful AIMI diagnostic, able to remotely sense the fundamental state
parameters of the ionospheric plasma (Ne, Te, Ti, Vi) as a function of range and time. Through the use of
ancillary models, higher-order parameters can also be resolved, including conductance, ion composition,
Joule heating, electric current systems, and neutral wind fields. The emergence of electronically steerable
ISRs in the previous decade has provided a major step forward in AIMI science. The Advanced Modular
ISR (AMISR) facilities have demonstrated enormous capabilities to study the ionosphere with
unprecedented resolution and precision. One example is provided in Figure 8.22, illustrating the
capability of the Poker Flat AMISR (“PFISR”) to observe the ionospheric signatures of gravity waves in
the critical 100- to 300-km altitude region. A second example is provided in Figure 8.24, illustrating the
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capability of an AMISR to measure ionospheric flow fields and ion temperatures over small spatial and
temporal scales.
In addition to boasting low operation and maintenance costs, low power requirements, and a
highly robust architecture, the AMISR facilities offer an extraordinary degree of experimental flexibility
that has not yet been fully realized. For instance, during the 2009 International Polar Year (IPY), the
PFISR facility was configured to record a vertical profile every 15 minutes for the entire year. This “low
duty cycle” mode was interleaved seamlessly with other experiments. Figure 8.25 shows an epoch
analysis of ionospheric effects caused by corotating interactions regions extracted from these data.
FIGURE 8. 25 Epoch analysis of ion temperature affected by the arrival of corotating interaction regions
over the course of a year, extracted from AMISR low duty-cycle measurements. SOURCE: J.J. Sojka,
R.L. McPherron, A.P. van Eyken, M.J. Nicolls, C.J. Heinselman, and J.D. Kelly, Observations of
ionospheric heating during the passage of solar coronal hole fast streams, Geophys. Res. Lett. 36:L19105,
doi:10.1029/2009GL039064, 2009. Copyright 2009 American Geophysical Union. Reproduced by
permission of American Geophysical Union.
AMISR facilities deployed in the southern hemisphere and in the southern polar regions will
contribute significantly to the understanding of inter-hemispheric variability that serves as the focus of the
longitudinal sensor network proposed above. Collocation of the proposed whole-atmosphere lidar with
such a deployment will lead to further advances in AIMI science by elucidating wave-plasma and plasma-
neutral interactions over a range of scales, as well as contributing to the understanding of the spatial and
temporal evolution of Joule heating. Thus, with successful AMISR deployments at Poker Flat (PFISR),
Resolute Bay (RISR), and planned deployments in Argentina and Antarctica, attention over the next
decade should turn to developing technologies and strategies to fully exploit the emerging “ISR network”
to address AIMI science objectives.
Develop and deploy phased-array ISR facilities in the southern hemisphere including Antarctica, and
develop the technologies and strategies to enable autonomous, extended, and coordinated operation of
these facilities.
Create a Medium-scale Research Facility (MRF) Program at NSF. The above facilities are candidates for
support by the NSF Geospace Program and would require that a Medium-scale (~$40 to $50 million)
Research Facility (MRF) funding program be instituted at NSF to fill the gap between the Major
Research Instrumentation (MRI, <$4 million) and Major Research Equipment and Facilities
Construction (MREFC, >$100 million) programs.
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8.5.3.4 Ionospheric Modification Facilities
Ionospheric modification using high-frequency (HF) radio transmitters, or “heaters,” provides a
powerful tool for exploring the physics of the upper atmosphere from the ground. Heating facilities treat
the ionosphere as a “laboratory without walls,” providing insight into complicated plasma physics
processes that occur elsewhere in the cosmos but that are difficult or impossible to explore in the
laboratory. Ionospheric heaters affect the propagation of radio signals; they generate airglow and radio
emissions that can be observed from the ground; they create plasma density irregularities that can be
studied using small coherent scatter radars; they provide access to chemical rate constants that are
otherwise hard to quantify; they accelerate electrons, mimicking auroral processes; and finally, they
modify plasma density and electron and ion temperatures and enhance the plasma and ion lines observed
by incoherent scatter.
The DOD operates and maintains the world’s largest ionospheric modification facility, HAARP,
near Gakona, Alaska. HAARP is not collocated with an incoherent scatter radar, and so its full potential
has not been realized since the phenomena it creates cannot be fully diagnosed. Figure 8.26 shows an
image of an artificial aurora created at the HAARP facility. Another ionospheric modification facility is
under construction at the Arecibo Radio Observatory. While this facility will be modest in power
compared to HAARP, its collocation with Arecibo, the world’s most sensitive incoherent scatter radar,
raises the prospect of discovery science in the areas of artificial and naturally occurring ionospheric
phenomena.
The Arecibo heater came about through close collaboration between the DOD and NSF. The
panel regards this kind of inter-agency cooperation as a model to be followed for the utilization of
existing ionospheric modification facilities as well as the planning and development of new ones.
Fully realize the potential of ionospheric modification techniques through co-location of modern heating
facilities with a full complement of diagnostic instruments including incoherent scatter radars. This
requires coordination between NSF and DOD agencies in the planning and operation of existing and
future ionospheric modification facilities.
FIGURE 8.26 Artificial aurora induced by high-power HF radiation from the HAARP heater facility.
The rayed structures are about 100 m in width and are aligned with the geomagnetic field. SOURCE:
Kendall, E., R. Marshall, R. T. Parris, A. Bhatt, A. Coster, T. Pedersen, P. Bernhardt, and C. Selcher
(2010), Decameter structure in heater-induced airglow at the High frequency Active Auroral Research
Program facility, J. Geophys. Res., 115, A08306, doi:10.1029/2009JA015043. Copyright 2010 American
Geophysical Union. Reproduced by permission of American Geophysical Union.
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8.5.4 Theory and Modeling
As noted in numerous examples within this chapter, cross-scale coupling processes are intrinsic to
IT system behavior. That is, phenomena highly structured in space and time (e.g., wave dissipation,
turbulence, electric field fluctuations) can produce effects (e.g., wind circulations, chemical transport,
Joule heating, respectively) over much broader scales. By the same token, larger-scale phenomena create
local conditions that can seed development of rapidly changing structures at small spatial scales (e.g.,
instabilities and turbulence). The current state of affairs is that parameterizations are formulated to
approximate the bulk effects of small-scale phenomena in global models whose spatial and temporal
resolutions preclude inclusion of physics at smaller scales. Often such parameterizations make ad-hoc
assumptions about the governing physics and coupling between scales, and are usually artificially “tuned”
to yield results in global-scale models that agree better with observations.
The observational strategies suggested in this report, which place high priority on understanding
how local, regional, and global-scale phenomena couple to produce observed responses at all scales, calls
for complementary development of theory and numerical modeling capabilities that enable self-consistent
treatment of cross-scale coupling processes. The fundamental physics of small-scale phenomena need to
be developed and understood, and numerical simulations performed that validate theories and explore
parameter space dependencies. These models need to be embedded in regional-scale models so that two-
way interactions are self-consistently addressed, and regional-scale models need to be nested at strategic
locations within global models to enable cross-scale coupling processes and their implications to be truly
understood and emulated.
Finally, it is well known from terrestrial weather forecasting the concept of assimilating real-time
data to nudge the solutions of physics-based models towards the observed state of the system. Global
weather models assimilate data of various types over the globe to provide local, regional, and global
forecasts as part of our daily lives. A similar path needs to be followed for the IT system to attain a true
space weather forecast capability. During the next decade, assimilative models for the IT need to be
developed, and such models need to be explored to reveal the types and distributions of measurements
that provide optimal characterizations of the system at local, regional, and global scales.
Therefore, in keeping with the synergy between the science goals, spaceflight missions, and
ground-based facilities advocated by this panel, the following imperatives in the area of theory and
modeling are presented:
Comprehensive models of the AIM system should develop embedded grid and/or nested model
capabilities, and use them to understand the interactions between local- and regional-scale phenomena
within the context of global AIM system evolution.
Complementary theoretical work should be encouraged to understand the physics of various-scale
structures and the self-consistent interactions between them.
Comprehensive models of the AIM system should develop assimilative capabilities and serve as the first
genre of space weather prediction models002E
8.5.5 Enabling Capabilities
The missions and initiatives above will not be successful if there is not an infrastructure of
additional capabilities that enable cheaper and more frequent measurements of the AIM system, that
transform measurements into scientific results, that maintain the health of the scientific community, and
that serve the needs of 21st-century society. These enabling capabilities (i.e., working group imperatives)
fall into the following categories: These enabling capabilities fall into the following categories:
innovations: technology, instruments and data systems; theory, modeling and data exploitation; research
to operations-operations to research; workforce and education, and are detailed below.
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8.5.5.1 Innovations: Technology, Instruments and Data Systems
Key Instrument Development
Principal among the challenges presented to AIM science is a description of the neutral wind over
the altitude range from 90 km to 300 km where a transition from a collision dominated to magnetized
atmosphere occurs. Neutral wind instrument development for space is high priority for AIM science.
Furthermore, general reductions in mass, power and volume of AIM space sensors would increase the
effectiveness of small-satellite missions. Early action in instrument and technology development would
lower cost and risk when called upon for a satellite mission. This performed alongside a revitalized
Explorer program, a new HITDP would be highly complementary and support rapid scientific
advancement.
An expanded instrument development program should be initiated, to enable new observational advances
that reduce cost risk and “threats” when implemented as part of satellite missions.
Data Access
The AIM community uses a wide variety of heterogenous data sets sampling regions throughout
the geospace system, taken by space- and ground-based instruments, some of them in networks or arrays.
The synthesis of data sets within arrays, with other data sets and with global and regional models to
explore frontier science issues is a major challenge for the future. The Solar and Space Physics
Information System (SSPIS) was created to enable access to, and digital searching of, the many
distributed data resources managed or utilized by NASA. It currently consists of a set of VxOs providing
access to distributed data sets with Space data model descriptors. New search and analysis technologies
that make use of these core capabilities are now possible with potential for significantly enhancing AIM
research. SSPIS will face major challenges in the near future of providing data services for manipulation,
visualization, and storage of terabyte data sets and model outputs. The development and implementation
of new capabilities is extremely slow given the minimal funding levels of the program (only 1 percent of
the NASA Heliophysics budget). VxOs have developed to the point that software tools can now be built
by end users to support scientific studies that could not conceivably been performed before. For geospace
regions that are populated by heterogenous sensors, this is an important capability for revealing the
processes that drive the development of structure and change in the system.
Create enhanced VxO and interactive data access for system level understanding.
8.5.5.2 Theory, Modeling and Data Exploitation
Programmatic Support
High priority AIMI science throughout this chapter focuses on multi-scale coupling, emergence,
nonlinear dynamics and system-level behaviors. This focus sets new requirements for research programs,
computational technologies and data analysis needs. Discovery science in all these areas requires a means
of understanding the global connections, sometimes across vast distances or very disparate spatial or
temporal scales, while at the same time developing a deep understanding of the individual regions and
processes that are elements of these connections. Coupling within the AIM system and with other
elements in the Sun-Earth system span time scales from seconds to centuries and serves to refocus efforts
in understanding global change and the role of solar variability in climate. Attacking planetary change
and space climate issues is dependent on the availability of historical data sets and continuity in
observations of key AIM parameters like atmospheric temperatures, composition and cooling rates and
solar inputs like spectral irradiance and interplanetary magnetic field. Finally the future of assimilative
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modeling in space weather prediction rests on a continuing supply of near real-time observations of the
AIM system that provide information on large-scale features like the auroral zone and equatorial
electrojet as well as small-scale gradients relevant to the triggering of ionospheric instabilities.
Advances in computer power and speed have reached the point where self-consistent simulations
of multi-scale coupling in the AIM system are already possible. Existing peta-scale computers have
reached 300,000 cores and powerful mega-core computers are expected in the next decade to provide the
computational equivalent of 1-10 million CPU cores. These computational advances will drive a
revolution in the realism of simulations and the ability to reproduce the self-consistent global signatures
of small-scale processes. These advances in modeling in a very real sense parallel the innovations in
observational programs that are high-priority targets in this chapter. An investment in a range of
technological capabilities is needed to take full advantage of these powerful computational resources,
including new multi-scale, multi-physics algorithms (such as adaptive mesh refinement), computational
frameworks that couple physics across disparate time and spatial scales, innovative ways to mine,
visualize, and analyze massive amounts of data produced by the next generation of multi-scale
simulations, and data assimilation technologies essential to improve space weather forecasting tools.
These requirements and technological advances compel the following:
Establish a re-balanced and expanded Research and Analysis Program with the following elements:
• Solar and Space Physics (Heliophysics) Science Centers: a new program of
interdisciplinary centers (Heliophysics scientists with computational experts) that leverages the power of
peta-scale computers to create powerful physics-based multi-scale models of the AIM system and its
coupling to other regions, alongside parallel efforts in data assimilation and data fusion. Similar
interdisciplinary theory and modeling efforts in the range of $1.5 million to $5 million per year over 3 to
5 years duration but not focused specifically on geospace are funded through NSF through their
Frontiers in Earth System Dynamics (FESD), and AFOSR through their Multidisciplinary Research
Program of the University Research Initiative (MURI) program. NASA funds smaller scale modeling
efforts within the strategic capabilities category in the Living with a Star Targeted Research and
Technology (TR&T) program. Given the large costs of these programs, it may best that NASA, NSF and
AFOSR coordinate their funding of these multidisciplinary programs in order to avoid duplication and
ensure essential projects are funded.
• A Strengthened NASA Theory Program that supports critical mass groups responding to
new theoretical challenges in AIM science using a wide variety of research approaches.
• An enhanced data analysis program (attached to satellite missions and ground-based
facilities) that provides a level of support needed to convert new and archived AIM observations into
knowledge and understanding.
• An upgraded R&A program that is a reasonable fraction of the overall AIM budget to make
sure that expenditures in the program are converted to major advances in science.
AIMI Data Environment
The innovative observational and modeling programs described in this document will provide
essential new information about how the AIM system works. However, this information will be
embedded in the relationships between data sets as well as within the individual data sets themselves. It
will be buried in peta-bytes of simulation data and in large volumes of heterogeneous data from new and
ongoing space missions, from major new ground-based facilities, from suborbital platforms, and from
arrays of ground-based all-sky cameras, lidars, radars, magnetometers, GPS receivers, ionosondes,
imagers, and other instruments. There must be a parallel effort to develop the tools needed to convert the
volumes of data into new knowledge about the AIM system. The challenge is to combine these
heterogeneous data sources, housed in archives distributed around the world, into new browse summaries
and new data products that contain information about AIM system behaviors in addition to the regional
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and process information contained in the individual data sets themselves. In turn, this global view will
provide needed context for the interpretation of small-scale features and local observations.
Because of these requirements, new efforts in data exploitation and data synthesis are essential
ingredients for the future of the AIM research environment. As data sources grow in size and complexity,
exploiting the data requires being able to (1) locate specific pieces of information within a large
distributed set of worldwide data archives, (2) manipulate and visualize the data while retaining
knowledge of version information and all supporting analysis programs, and (3) combine data sources to
create new data products while maintaining linkages back to the original data sources. This is where the
development of data synthesis capabilities is essential. In the face of constrained budgets, much of this
effort can be accomplished by using robust and sustainable commercial off-the-shelf (COTS)
technologies that keep pace with new developments. To make heliophysics data “findable” by these
commercial technologies requires the development of standard text-based metadata descriptors. Much of
the groundwork for this capability has taken place in the last few years with the creation of an array of
virtual observatories and the continuing development and implementation of the international Space
Physics Archive Search and Extract (SPASE) data model.
The full and complete implementation of SPASE opens the way for the development of an array
of shared software tools for essential capabilities in data mining, pattern recognition, statistical analyses,
data visualization, etc., both on the client side and on the server side in the case of large data volumes.
Virtual observatories also enable the development of tools that require detailed information about
instruments not easily obtained by individual investigators. One example is the calculation of common
volumes in which in situ and remote-sensing measurements are made or in which space- and ground-
based observations intersect.
Develop a data environment that preserves important elements of the current Heliophysics data
environment, while expanding the capabilities in directions that enhance data exploitation to maximize
the scientific value of the data sets.
Data Synthesis
Essential to many of the AIM science frontiers identified in this document, is the ability to
synthesize information from multiple data sets into new knowledge about the AIM system. This includes,
for example, mapping between geospace data sets using magnetic fields from continuously running MHD
simulations, browse products that superpose observations along satellite tracks onto global patterns from
constellations or imagers, maps that combine information from a large number of individual ground-based
instruments into global views, and combinations of ground- and space-based observations that address
space-time ambiguities, among others.
Explore new data synthesis technologies to leverage the many types of AIM data into new knowledge of
the AIM system required for accelerating progress on AIM system science frontiers.
Heterogeneous Data Sets
To accomplish AIM goals in the coming decade, a data environment is needed that draws
together new and archived satellite and ground-based geospace data-sets from U.S. agencies as well as
international partners. This effort is needed to obtain the best possible coverage of the geospace system
and describe its evolution over time. This data environment should also provide access to operational
space weather data sets, climatological data sets, archived simulation outputs and the latest technological
advances in digital searching, storage and retrieval; data mining, fusion, and assimilation; as well as
client-side and server-side data manipulation and visualization. These ground and space assets represent
a large investment and are vital for the system science goals of the AIM program. The full value of that
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investment will only be realized if adequate funding is provided. The present solar and space physics
information system (SSPIS) could naturally form the core of this program. The valuable multi-agency and
international efforts to unify standards and increases interoperability through agreements on data and
metadata formats and communication protocols started under the SSPIS program must be an essential
component of this effort.
Increase the investment in the acquisition, archiving, and ease of use of geospace data sets.
Long-Term Data Sets
NASA and NSF should identify essential long-term data sets and pursue maintenance and
preservation through funding within the Heliophysics data environment activities and related NSF data
archives. Some of this data, not in digital formats yet are in danger of being irretrievably lost. A larger
problem is the continuity of key long-term data sets, for example, solar spectral irradiance, and 30-years
of particle precipitation on operational satellites. Mechanisms do not yet exist to continue such data sets
outside of competing against new satellite missions. New mechanisms must be established to add
instrumentation where possible on rides of opportunity and to partner with other agencies to re-establish
space environment monitors on key operational satellite payloads.
Establish mechanisms for maintenance and continuity of essential long-term data sets.
Laboratory Experiments
Modeling planetary atmospheres and interpreting information in airglow and auroral emissions
from Earth’s atmosphere, planetary bodies, and comets requires detailed knowledge of differential cross
sections, and reaction rates. The extraction of information about planetary environments from these
emissions and the design of new and innovative remote sensing instrumentation is dependent on accurate
cross section information. Laboratory experiments are a primary source of this information with a long
history of advancing the discovery of fundamental processes in all of these environments. Critical
information on rates and cross sections for key atomic and molecular processes are still lacking. One
particular example where cross-section information is highly uncertain and has impeded progress is
oxygen ion precipitation and backsplash during extreme space weather events.
Establish a Program of Laboratory Experiments Joint between NSF, NASA, and the DOE that Includes
Measurements of Key Cross-sections and Reaction Rates.
8.5.5.3 Research to Operations—Operations to Research
Research is the foundation for future improvements in space weather services. Presently,
ionospheric models are just beginning to reach a level of maturity where they can benefit space weather
customers. But at the same time, a major decline in support for model development and improvement,
which is critical to operational entities, is being witnessed.
Furthermore, model development aimed at improving forecasts requires a dedicated effort
focused on validation and verification. Also, in order to quantify a model performance, there is a need to
establish a standard set of metrics for space weather products. Under NASA, NSF, NOAA, and AFOSR
sponsorship, a standard set of metrics and skill score most appropriate for a given space weather
application need to be selected that would reflect operational needs. Metrics and skill score should also
be used to quantify progress with each new model version.
In order to reduce “the valley of death” that separates research models and operational systems, it
is also suggested that operational and research agencies fund open-source models. Open source
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operational models have the potential to minimize the cost of transitioning research models to operations
and of maintaining the models.
Improve the effectiveness and level of support for model development, validation, and transition to
operation.
Existing and planned assets that are routinely used for purposes other than space weather often
have capabilities that could be utilized to return valuable space science measurements. With minimal
investment, important data can be obtained from these instruments. One very low-cost example includes
tasking on a daily basis the Altair radar at Kwajalein to measure ionospheric parameters (electron density
and plasma irregularities). This can easily be done during short periods interlaced between scheduled
radar target acquisitions. These measurements would also benefit the users of the Altair system by
providing a method to detect and forecast possible scintillation problems that could affect the radar data.
Seek high leverage opportunities for acquiring new measurements.
It is widely recognized that space environment data provided by NOAA and DOD operational
satellites for almost four decades are essential to AIMI science. Data from these satellites are of
fundamental importance for space weather forecasting. They are among the most often used data sets for
space science research on ionosphere/magnetosphere coupling. In addition, they are essential to study
long-term climatic changes in geospace. The following 3-part imperative follows:
Leverage National Investments in Operational Satellite Data for Scientific Progress: (1) NOAA and DOD
should maintain the space environment sensing capability that has provided data for almost four decades,
and continue acquiring observations from LEO satellites of particle precipitation, ion drifts, ion density
and magnetic perturbations similar to those measured from POES and DMSP. (2) Open data policies
should be negotiated with DOD, DOE and other agencies (that also safeguards national security
concerns). (3) The DOD, NOAA and NASA should coordinate the archiving of these data sets, making
data accessible and creating tools that provide for ease of use. The present solar and space physics
information system (SSPIS) could naturally form the core of this program.
8.5.5.4 Workforce and Education
The AIMI community recognizes the increasing need to promote education and training in all
aspects of space science and space technology. At the same time, few educational institutions have the
breadth within their faculty, or the student numbers within a department to facilitate a complete AIMI
curriculum. Thus it is important to afford the opportunity for students and faculty to participate in
programs that bring together different expertise from different institutions into intensive training sessions
in order to fill this pedagogical gap. NSF, NASA, and DOD should continue to support the development
and execution of summer schools and workshops to provide a full spectrum of instruction in geospace
science and technology. This is considered essential to the proper development of the next generation of
space scientists and engineers. NSF should continue its Faculty Development in Space Sciences (FDSS)
program, which provides incentive for universities to hire faculty in geospace research. The federal
government should revise export control policies to exempt basic space research from government
restrictions such as those mandated under ITAR.
As described above, expand and promote education and training opportunities to develop the future
generation of AIM scientists and engineers.
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Seek high leverage opportunities for acquiring new measurements.
It is widely recognized that space environment data provided by NOAA and DOD operational
satellites for almost four decades are essential to AIMI science. Data from these satellites are of
fundamental importance for space weather forecasting. They are among the most often used data sets for
space science research on ionosphere/magnetosphere coupling. In addition, they are essential to study
long-term climatic changes in geospace. The following 3-part imperative follows:
Leverage National Investments in Operational Satellite Data for Scientific Progress: (1) NOAA and DOD
should maintain the space environment sensing capability that has provided data for almost four decades,
and continue acquiring observations from LEO satellites of particle precipitation, ion drifts, ion density
and magnetic perturbations similar to those measured from POES and DMSP. (2) Open data policies
should be negotiated with DOD, DOE and other agencies (that also safeguards national security
concerns). (3) The DOD, NOAA and NASA should coordinate the archiving of these data sets, making
data accessible and creating tools that provide for ease of use. The present solar and space physics
information system (SSPIS) could naturally form the core of this program.
8.5.5.4 Workforce and Education
The AIMI community recognizes the increasing need to promote education and training in all
aspects of space science and space technology. At the same time, few educational institutions have the
breadth within their faculty, or the student numbers within a department to facilitate a complete AIMI
curriculum. Thus it is important to afford the opportunity for students and faculty to participate in
programs that bring together different expertise from different institutions into intensive training sessions
in order to fill this pedagogical gap. NSF, NASA, and DOD should continue to support the development
and execution of summer schools and workshops to provide a full spectrum of instruction in geospace
science and technology. This is considered essential to the proper development of the next generation of
space scientists and engineers. NSF should continue its Faculty Development in Space Sciences (FDSS)
program, which provides incentive for universities to hire faculty in geospace research. The federal
government should revise export control policies to exempt basic space research from government
restrictions such as those mandated under ITAR.
As described above, expand and promote education and training opportunities to develop the future
generation of AIM scientists and engineers.
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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