Space Weather and Ionospheric Research Using COSMIC Data

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Space Weather and Ionospheric Research Using
COSMIC Data

• Qian Wu. S. C. Solomon, Wenbin Wang, Alan Burns,
• Liying Qian, Mike Wiltberger, T. L. Killeen
• High Altitude Observatory
• National Center for Atmospheric Research
• For COSMIC Retreat October 28, 2004
• Peaceful Valley Ranch, Colorado

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Overview

• Space Weather
• Solar X-ray flare effect on the ionosphere
• Auroral oval expansion and precipitation
  enhancement during geomagnetic storms
• Polar cap absorption events
• Equatorial anomaly
• Plasmasphere depletion and refilling during and
  after storms
• F region ion density variation during storms
• Ionosphere and thermosphere modeling efforts at
  HAO
• Possible collaboration between the COSMIC team
  and HAO group on ionosphere studies

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Solar Activities and Space Weather
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Space Weather Overview

• Solar activities control the space weather
• X-ray flare
• CME
• Enhanced solar wind (density, speed increases)
• Southward turning of the interplanetary magnetic
  field
• X-ray ionization enhancement in D region
• Precipitation of energetic protons (MeV) inside
  the polar cap
• Reconnections of the Earth magnetic field lines
• Releasing energy inside the magnetosphere
• Auroral enhancement
• Expansion of the auroral oval
• Enhancement of cross polar cap potential and
  strong anti-sunward convection in the polar cap
• Penetration of the high latitude electric field
  to mid- and lower latitude region
• Plasmapause movement due to storm
• Joule Heating in the high latitude upper
  thermosphere
• F region ion density changes

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Solar X-ray Flare
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SolarX- ray Flare of November 4, 2003
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Photo-ionization Thermosphere is heated
by absorption of parts of the solar EUV
spectrum Photons are sufficiently energetic to
ionize the gas Ionospheric profile will
differ from day to night Results in an
electrically neutral plasma, mainly electrons and
positive ions attachment processes can produce
negative ions also Ionosphere stratified into D,
E, F1, and F2 layers
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D Region Ionosphere enhancement During X-ray Flare
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Coronal Mass Ejection (CME)

• Coronal mass ejections (CME) are huge bubbles of
  gas threaded with magnetic field lines that are
  ejected from the Sun over the course of several
  hours.
• Coronal mass ejections are often associated with
  solar flares and prominence eruptions.

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CME Event Example
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IMF and Kp index
300
301
302
303
304
305
306
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Auroral Oval Expansion and Precipitation
Enhancement During Geomagnetic Storm
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Solar Proton Event and Polar Cap Absorption Event

• Energetic solar protons (MeV) precipitate into
  the polar cap through the open field lines.
• Strongly enhance the D-region ionosphere
• Causing enhanced absorption of cosmic radio
  noises ( 30 MHz), which are monitored by
  riometers (Relative Ionospheric Opacity METER) on
  the ground in the polar cap.

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Riometer Signal Level vs Quiet Day Curve
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Cosmic Radio Noise Absorption Due to A Polar Cap
Absorption Event
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Equatorial Anomaly

• Ionosphere enhancement on two sides of the
  geomagnetic equator.
• Caused by the fountain effect from the F-region
  eastward electric field.
• The F region eastward electric field is caused by
  the E-region dynamo generated by the lower
  thermosphere neutral winds (mainly the diurnal
  tide).
• E-region dynamo can be affected by penetration of
  high latitude electric field during geomagnetic
  storms

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Diagram for Equatorial Anomaly
E x B
E (eastward electric field) Looking west
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Equatorial Anomaly
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GPS TEC Observation of Equatorial Anomaly During
Geomagnetic Storms
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Plasmasphere

• Plasma in donut shape corotates with the Earth
• Cold (1 eV),
• Dense (up to 103/cm)
• Populated by the outflow of ionospheric plasma
  along mid- and low-latitude magnetic field lines
  lt 60 MLAT
• H 80 , He 20

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Plasmasphere During Storms

• When the magnetosphere is disturbed by a magnetic
  storm, enhanced convection "erodes" the outer
  plasmasphere, capturing plasma in the
  afternoon-dusk sector and transporting it outward
  and sunward toward the magnetopause. Some of the
  eroded plasma convected to the magnetopause may
  escape into the solar wind, while some is thought
  to be transported into the magnetotail and
  eventually into the plasma sheet.
• Following erosion, which can last hours to tens
  of hours, plasma flowing upward along magnetic
  field lines from conjugate ionospheres begins to
  "refill" the depleted plasma trough and
  plasmasphere. Refilling of the plasmasphere
  typically requires several days.

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F-region Ionosphere Variation During Storms

• Enhanced polar cap ion convection due to increase
  in the cross-polar-cap potential
• Energy transferred into
• Kinetic energy (increase neutral winds in the
  thermosphere)
• Joule heating (increase temperature in the
  thermosphere)
• Raising molecular species into the upper
  thermosphere
• Increase ion recombination and reduce the ion
  density in the F-region

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TING Model Simulation of F-region Ionosphere
During Storms
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Modeling Efforts in Our Group

• Center for Integrated Space Weather Modeling
  (CISM) is a NSF supported Science and Technology
  Center started in August 2002 to build a
  comprehensive, physics-based computer model that
  can accurately simulate the complex, closely
  interconnected variables from explosions on the
  sun to aurora on the earth and almost everything
  in-between
• HAO is involved in the magnetosphere and
  ionosphere coupling modeling.
• Thermosphere and Ionosphere Nested Grid model
  (TING)
• The Whole Atmosphere Community Climate Model
  (WACCM) is a comprehensive model of Earths
  atmosphere from the surface to 140 km.
• HAO is involved in modeling solar variability on
  the middle and upper atmosphere and their
  possible links to the troposphere.
• Including the solar X-ray effects on the
  ionosphere
• TIME-GCM The thermosphere-ionosphere-mesosphere-el
  ectrodynamics general circulation model
  (TIME-GCM) is the most elaborate of the
  upper-atmospheric TGCM's and it solves for global
  distributions of neutral and plasma temperatures,
  velocities, and compositions, including all of
  the species that are photochemically important in
  the mesosphere, thermosphere, and ionosphere.
• Including the proton event effect on the polar
  cap ionosphere

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Simulation of E and F region enhancement during
X-ray flare
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Collaboration between COSMIC Team and HAO group
for Ionosphere Study

• Validation of the ionosphere model output.
• Use COSMIC data as input for auroral oval
  location.
• Testing X-ray flare effect on the ionosphere.
• Examine the effect of the geomagnetic storm on
  the equatorial anomaly (enhancement, asymmetry,
  and location).
• Study the polar cap absorption events to see how
  the enhanced ionization can affect the
  ion-neutral coupling in the polar cap.
• Study the plasmasphere movement during storms.
• Study F-region ionosphere variations during
  storms.
• Model output can be used in COSMIC data inversion
  as the first guess.