Ionospheric Weather Monitoring by
FORMOSAT-3 and ground-based
GPS receivers
Tiger J.Y. Liu NSPO, TAIWAN
I.T. Lee CWB TAIWAN
Y.Y. Sun, C.Y. Lin, C.T. Hsu NCU TAIWAN
T. Matsuo NOAA, USA
W. Wang NCAR USA

Content• The 7 January 2015 Dst= -99nT magneticstorm• Ionospheric DA model (F3/C)• TGIM model (F3/C + gb GPSR)• Magnetic+ (F3/C + gb GPSR)• SummaryFORMOSAT-3/COSMIC
Global Real-time
Weather (Meteorology)
Space Weather (Ionosphere)
Observation and Prediction
The FORMOSAT-3/COSMIC program is an international
collaboration between Taiwan and the United States thatwill use a constellation of six remote sensing microsatellites
to collect atmospheric data for weather prediction and forionosphere, climate and gravity research. Data from thesatellites will be made freely available to the international scientificcommunity in near real-time.

FORMOSAT-3/COSMIC• FORMOSAT-3/COSMIC
Constellation was launch at
01:40 UTC, April 14, 2006
(Taiwan Time: April 15 2006) at
Vandenberg Air Force Base,CA. Minotaur Launch• Maneuvered into six different
orbital planes (inclination ~72°)
for optimal global coverage (at~800 km altitude).
• Five out of Six satellites are ingood health and providing
science data.

GPS Radio Occultation

αWavelength and amplitudeof in the vertical direction
Global 3D structure

Distribution of occultation events
observed by FORMOSAT-3GOX7 January 2015 storm

Ionospheric Assimilation Model
NCAR Thermosphere Ionosphere E-GCM
FORMOSAT-3/COSMIC (Electron density profiles)
Data Assimilation Research Testbed
Lee et al. [JGR 2012, JGR 2013] , Hsu et al. [JGR 2015]

NmF2 map

Along 120°E

Taiwan Global Ionosphere Map(TGIM model)
IGS GPS Receivers (total electron content; TEC)FORMOSAT-3/COSMIC (vertical TEC)
Spherical harmonic surface functions
Sun et al. [2015]

Magnetic EOF Data Assimilation model
IGS GPS TECFORMOSAT-3/COSMIC (Radio Occultation TEC)
International Reference Ionosphere (IRI)
Kalman Filter with a 3-D Error Covariance
Empirical orthogonal functions (EOF)
Lin et al. [AMT 2015]

Storm signatures in TGIM and EOF DA
13:00 UTC Jan 07 2015
Jan 062015

EOF DAJan 072015

Jan 07 – Jan 06

TGIM

CODE GIM

RO Observation

Ionospheric Data Assimilation 3-D structure
13:00 UTC Jan 07 2015

Ionospheric Data Assimilation
3-D structure Difference
13:00 UTC Jan 07 2015

FORMOSAT-7/COSMIC-2

FORMOSAT-3/COSMICFORMOSAT-7/COSMIC-2

Exterior DesignSequence

1st Launch

2nd LaunchConstellation

666

Mission Orbit
Altitude

800 km520-550 km

720-750 km

Inclination Angle

72°

24-28.5°

72°

Mission Payload

GOX

TriG

RO Signals

GPSGPS, GLONASS, Galileo

Launch Schedule

Launched in 2006

• Descriptions are provided by NSPO (http://www.nspo.org.tw).
• F7/C2 is illustrated by Surrey Satellite Technology LTD.

20162018

F7/C2 vs F3/C
With 6 satellites + GPS, 60 minutes
About 80-100 profiles per hourWith 12 satellites + GPS, 60 minutes
About 400 profiles per hour

Ionospheric Weather Monitoring• Solar activity variations• Seasonal variations• Monthly variations• Tidal effects• Diurnal variations• Semi-diurnal variations• Disturbed period effects• Other temporal variations• Irregularities
Latitudinal slices are at -120°, -60°, 0° 60° and 120° longitude with a interval of ±2.5°.

Could it be advanced by F7/C2 ?

Simulated F7/C2 observations at 08:00 UT within 1 hour x 1 day accumulation period

12 satellites,
28 GPS and
24 GLONAAA

Lee et al. [2013]

Summary• TIEGCM DA for the first time includes the neutral
atmosphere which can be used to carry out the long term
ionospheric weather prediction.
• TGIM issues the global TEC map every 10 minutes currently
with a 4-hour time delay.
• EOF DA provides the global 3D electron density structure.
• The three models detect the ionospheric signatures of the7 January 2015 storm.
• TGIM+EOF DA will be the next product for the short termionospheric weather prediction.
• FORMOSAT-7/COSMIC-2 shell open a new chapter for theionospheric weather monitoring and Prediction.

Thank you

Thank you!!!
FORMOST-7/COSMIC-225