polar gateways meeting barrow, alaska, jan 23-29, 2008 1 dieter bilitza gsfc, code 672, greenbelt,...
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Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
http://IRI.gsfc.nasa.gov 1
Dieter Bilitza GSFC, Code 672, Greenbelt, Marylandand George Mason University, Virginia
International Reference Ionosphere and the
Polar Ionosphere
Introduction and Current Status Polar Ionosphere Auroral Characteristics from TIMED/GUVI IRI-2007 and some Applications
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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INTERNATIONAL REFERENCE
IONOSPHERE (IRI)Terms of Reference
•The IRI Working Group was established to develop and improve a reference model for the most important plasma parameters in the Earth ionosphere.
• IRI is a joint project of COSPAR and URSI. COSPAR’s (Committee on Space Research) prime interest is in a general description of the ionosphere as part of the terrestrial environment for the evaluation of environmental effects on spacecraft and experiments in space. URSI’s (International Union of Radioscience) prime interest is in the electron density part of IRI for defining the background ionosphere for radiowave propagation studies and applications.
•The model should be primarily based on experimental evidence using all available ground and space data sources and should not depend on the evolving theoretical understanding of ionospheric processes. But theoretical considerations can help to find the appropriate mathematical functions, to bridge data gaps and for internal consistency checks.
• As new data become available and as older data sources are fully evaluated and exploited, the model should be revised in accordance with these new results.
•Where discrepancies exist between different data sources the IRI team should facilitate critical discussions to determine the reliability of the different data bases and to establish guidelines on which data should be used for ionospheric modeling.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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B. ReinischD. Bilitza T. Fuller-RowellK. Bibl X. Huang J. Sojka D. Anderson V. WickwarL. ScherliessM. Codrescu S-R ZhangC. Mertens
M. Abdu
R. Ezquer M. Mosert de Gonzalez A. Poole,
L.-A. McKinnellJ. Adeniyi
P. Bradley, M. Rycroft, Lj. Cander (U.K.), K. Rawer, W. Singer (Germany), A. Alcayde, R. Hanbaba (France), B. Zolesi, S. Radicella (Italy), M. Friedrich (Austria),E. Kopp (Switzerland), D. Altadill (Spain)
A. Danilov V. K. Depuev T. Gulyaeva G. Ivanov-KholodnyK. Ratovsky A. Mikhailov
K. OyamaK. Igarashi S. Watanabe
K. Mahajan S.P. Gupta P.K. Bhuyan
P. Wilkinson P. Dyson B. Ward
L. Triskova, V. Truhlik (Czech Rep) I. Kutiev (Bulgaria) I. Stanislawska (Poland), S. Kouris (Greece)
IRI Working Group Members
O. Obrou
S. Pulinets
W. WeixangM.-L. Zhang
S.-Y. Su
Kyoung Min
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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2004C4.2 Advances in Specifying Plasma
Temperatures and Ion Composition in the Ionosphere
2005
New Data for Improved IRI TEC
representation
New Satellite and Ground Data for IRI and Comparisons with Regional
Models
2006Oct 16-20
2007 IRI/COST Workshop: Ionosphere – Modeling, Forcing and Telecommunications,
2008COSPAR GA, Montreal, Canada, July 13-20C4.2 - Updating IRI with ground and space data
Volume 39 Issue 5
2007
C4.2 - Solar activity variations of
ionospheric parameters.
Volume 37 Issue 5
2006
In press
Paris, France
Ebro, Spain
URSI GA, Chicago, August 9-16G02 – Density Profiling and Models
Prague, Czech Republic
In pre-paration
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International Reference IonosphereMonthly averages in the altitude range 50-1500 km:
+ Electron density + Electron temperature+ Ion composition (O+, O2
+, NO+, Cluster+, N+, He+, H+) [charge neutrality: Ne = ∑ni ]
+ Ion temperature+ Ion drift (currently only equatorial
vertical F-region drift)+ spread-F occurrence probability (currently
limited to South-American sector)
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Data Sources
Instrument Platform Used for Comments
Ionosondes Worldwide Ne from E Fifties to Network to F2 now
Incoherent Jicamarca, Ne profile Few radars,Scatter Arecibo, (E- valley) many Radar St. Santin, Te, Ti parameters MillstoneH., Malvern,
Topside Alouette 1, 2 Ne topside newer data Sounder ISIS 1, 2 profile from Ohzora, ISS-b, IK-19Insitu AE-C,-D,-E Ne topside many more: Aeros-A,-B profile,Te,Ti, DMSP, OGO
IK-24, DE-2 ion comp. HinotoriRocket data Ne D-region, sparse compilations Ion comp. data set
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Build-up of IRI electron density profile
Mathematical functions:
Global Variations: Spherical harmonics, special functions
Time Variations: Fourier, simple sin/cos, step-functions
Height Variations: Epstein functions Global models for
foF2/NmF2, foF1/NmF1, foE/NmEhmF2/M(3000)F2, hmF1 , hmE
Normalized to E and F peaks
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Ionosonde stations represented on NGDC CD-ROM
Digisonde stations
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Middle and Low Latitudes: Good data foundation; Well tested and evaluated; Good description of variations with height, latitude, longitude, local time/solar zenith angle, season/month, solar and magnetic activity; Now considered the standard (ISO and ECSS).
High Latitudes (auroral, polar): Sparse data record; Only few modeling efforts; Need to consider dependence on IMF and magnetospheric magnetic field; Highly variable; Modeling needs to include representation of many special features, like troughs, ovals, holes, crests (density/temperature enhancements and depletions); IRI provides background ionosphere based on few high-latitude ionosondes; Modeling of auroral and polar ionosphere
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Auroral and Polar Ionosphere• The solar wind, consisting mainly of protons and electrons moving at ultra-sonic speeds of 400 - 800 km/s (more than a million miles per hour).
• The solar wind pressure strongly compresses the Earth’s magnetosphere on the dayside and draws it out into an extremely long tail on the nightside.
• Electrons out of the solar wind are able to diffuse into magnetospheric tail and form a reservoir called the plasma sheet. The magnetosphere and the solar wind form an enormous electrical dynamo including one component which carries electrons down magnetic field lines where eventually they collide with the atmospheric gas causing it to glow.
• On the dayside solar wind particles have direct access to the Earth's atmosphere via the cusp regions.
Cusp
Cusp
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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A glowing band loops around the southern polar region in the distance as viewed by astronauts onboard the space shuttle.
Oval latitudes span Fairbanks, Alaska, Oslo, Norway, and the Northwest Territories.
Polar VIS
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Each oval consists of a band of auroral glow within which are embedded visible auroral arcs, bands and other shapes. The two auroral ovals pivot around the earth's geomagnetic poles, located near Thule, Greenland and Vostok, Antarctica. They are displaced somewhat toward the nightside of the earth with the consequence being that the ovals extend to lower latitude at night than they do in daytime. When conditions in the solar wind blowing out from the sun to the earth are quiet, the auroral ovals contract poleward and become quite narrow. During active conditions the ovals enlarge in diameter and widen. On rare occasions the northern oval may expand to reach southern California; likewise, the southern oval will expand toward the equator, simultaneously.
Kp=4
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Rotkaehl et al., 2007
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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The plots on this page show the current extent and position of the auroral oval at each pole, extrapolated from measurements taken during the most recent polar pass of the NOAA POES satellite. "Center time" is the calculated time halfway through the satellite's pass over the pole.
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IRI - Data Comparisons
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0 2 4 6 8 10 12 14 16 18 20 221
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12January 1996 - Base San Martin
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UT0 2 4 6 8 10 12 14 16 18 20 22
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Mosert, Prague 2007: Antarctic ionosonde at San Martín (68.1°S; Mosert, Prague 2007: Antarctic ionosonde at San Martín (68.1°S; 293.0°E geographic; 293.0°E geographic; 53° S magnetic53° S magnetic), ),
1996 (Rz=9.1)
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Belgrano (77.9°S, 321.4°E geographic; (77.9°S, 321.4°E geographic; 67.5° magnetic67.5° magnetic),),
0 2 4 6 8 10 12 14 16 18 20 221
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January 2000 - Base Belgrano
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April 2000 - Base Belgrano
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Figure 13
2000 (Rz= 117)
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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midnight noon
IRI
EISCAT Data
local model NmF2
hmF2
► IRI-foF2, extrapolated to 79°N, is not sensible
Friedrich and Fankhauser, Prague, 2007: EISCAT Svalbard, 78°N, L = 15.5300,000 profiles, 1997-03-11 to 2003-09-26
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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IRI - 2007
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Model for Ne in auroral lower ionosphere
[McKinnell and Friedrich, Adv. Space Res., 37(5), 2006]
● NeuralNet model trained with ~700,000 EISCATradar data points and 115 rocket profiles
● NN input space: local magnetic time (LMT), total absorption (Li), local magnetic index (K), solar zenith angle, F10.7 cm solar radio flux, pressure surface (p) (season, altitude)
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Year = 2002, Day = 182, Hr = 23.93 UT, ZA = 87°
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7 7.5 8 8.5 9 9.5 10 10.5 11 11.5
log(electron density, [m -3])
alti
tud
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km]
41.032 Rocket (McWave 1)
IMAZ
IRI-95
IRI-FPT
IMAZ at 0.0dB
IMAZ, no L
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Year = 1984, Day = 332, Hr = 3.42 UT, ZA = 117°
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F56 Rocket
IMAZIRI-95
IRI-FPT
IMAZ at 0.0dB
IMAZ, no L
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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IRI – New Developments
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Inclusion of Auroral Boundaries in IRIAuthors Instrument ParameterizationImage data:Feldstein and Starkov [1967] IGY All sky imager Q = 0, 1, 2, 3, 4, 5, 6Holzworth and Meng [1975] Mathematical representation of Feldstein-ovals in MLT, CGM, Q Carbary [2005] Polar UVI MLT, CGM, KpZhang and Paxton [2007] TIMED/GUVI MLT, CGM, Kp (energy flux, mean energy)
Particle data: Energy flux and mean energyWallis and Budzinski [1981] ISIS-2 MLT, InvLat, quiet and activeSpiro, Reiff, Maher [1982] AE-C, -D MLT, InvLat, 4 levels of mag activity (AE)Hardy, Gussenhoven et al. [1987] DMSP MLT, CGM, 7 levels (Kp)Fuller-Rowell and Evans [1987] NOAA/TIROS MLT, MagLat, Hemispheric power input PEM-2004 (see Cai et al. [2007]) FAST, EISCAT MLT, ILAT, AE
Electric field data: High-latitude convection patternHeelis, Lowell, Spiro [1982] AE-C, -D ion drift data MLT, only for Bz southwardHeppner and Maynard [1987] OGO-6, DE-2 MLT, CGM, IMF-Bz, Kp Rich and Maynard [1989]
One of the agreements among these models is that soft electrons are dominant in the cusp region around magnetic midday.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Maps of estimated electron energy flux (a) and mean energy (b) using GUVI data for orbit 00900 on February 6, 2002. The grid size is 30x30 km. The red and green lines with arrows are for the tracks of TIMED and DMSP F14. The tip of the arrow indicate the location of TIMED and DMSP F14 at 12:43:27 UT. (c) and (d): Comparison between results from GUVI and DMSP F14 along the DMSP F14 track. The two blue vertical lines indicate the region where the DMSP F14 electron energy flux is above 1.0 erg/(cm2-s).
Energy flux Mean energy
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Modeled electron energy flux (left panels) and mean energy (right panels) at four Kp values: 1, 3,5 and 7. The white circles are for magnetic latitudes. The red lines are for the equatorward and poleward boundaries of the oval at a fixed flux 0.25 ergs/(cm2 s). The yellow numbers are magnetic local time.
GUVI auroral models based on four years (2002-2005) of data and organized by magnetic latitude (Mlat), magnetic local time (MLT), and Kp (0-10).
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Nightside auroral boundaries (equatorward: black line, poleward: red line) and nightside peak electron flux location (green line) versus Kp.
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Left panel: DMSP F16 SSUSI auroral image over Greenland. The white bar over intense aurora (indicated by a solid red arrow) shows scan track of the Sondrestrom Incoherent Scatter Radar. Right: NmE, hmE along the white bar deduced from SSUSI UV measurements (blue line) and the radar NmE, hmE (red line).
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Global map of IRI peak E-region electron density NmE for July 2004 at 14:00 UTC [Solomon, 2006]. Contribution from precepetating electrons at high latitudes not yet included.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Krankowski et al., 2007: GPS-deduced trough location
Dependence on geomagnetic activity
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ud
e o
f tr
ou
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imu
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0 3 6 9Kp indices
3 6 9Kp indices
3 6 9Kp indices
D ecem ber, 1999
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/l= -1.9Kp+66.2
/l= -1.8Kp+60.9
/l= -1.6Kp+59.4
15-18 U T 21-24 U T18-21 U T
December 1999
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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IRI – Future Plans for High Latitudes:
Inclusion of Auroral Characteristics:
- Auroral Boundaries- Auroral NmE and hmE models including contribution fromprecipitating electrons- Representation of mid-latitude trough- Electron temperature enhancement
Effort would benefit from input of Barrow GPS and ionosonde data.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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THANK YOU
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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IMAZ model for auroral Lower Ionosphere
New model fortopside ion composition
Equatorial disturbance ion drift model
Spread-F occurrenceprobability model(Brazilian sector)
New models fortopside electron density
Akebono model for electron temperature in plasmasphere
IRI-2007
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Fig. 9. Ionization production rate caused by precipitating electrons with energies ranging from 100 to 1000 eV. (From Millward et al., 1999).
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Applications and
Usage
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Rios et al., JASTP, 2007, Tucuman Digisonde, Near Crest of Equatorial Anomaly
fo
F2
/ M
Hz
LT /hour
hmF
2 /
km LT /hour- - - IRI/URSI
Ionosonde
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Chau and Woodman JGR, Dec 2005
First Jicamarca D and E region density measure- ments (13 Dec 2004, 11 LT) and comparison with IRI.
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140
Alti
tude
/km
Jicamarca measurements
Friedrich et al. GRL, April 2006
Rocket (NASA EQUIS-II), 20 Sep 2004, near ALTAIR radar on Kwajalein Atoll (9N, 187E), 11:30 LST, SZA=19.7, Apogee = 131.2 km, F10.7= 101.
Comparison of Ne from nosetip probe, wave propagation experiment, ALTAIR, and the models IRI and FIRI.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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Comparison with KOMPSAT Kim et al., JASTP, 2006
Comparison of KOMPSAT-1 Te measure- ments in the low-latitude nighttime at 685 km with the two IRI Te options.
Newer option (Intercosmos) shows better agreement.
Te-Intercosmos
Te-ISIS, Aeros
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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STANDARD FOR ENGINEERING APPLICATIONS
• IRI is used as the standard in “Natural Orbital Environment Definition Guidelines for Use in Aerospace Vehicle Development” [NASA Tech Memo., NASA-TM-4527, 1994].
• IRI is the standard ionospheric model in “System Engineering – Space Environment” handbook of the European Cooperation for Space Standardization [ECSS, 1997].
• IRI was recognized as the international standard for the ionosphere in an official Commission G Resolution during the 1999 International Union of Radio Science (URSI) General Assembly.
• IRI is recommended by the International Telecommunication Union (ITU) for the computation of retardation effects on radio waves traveling through the ionosphere.
• IRI is the ionospheric model proposed in TS 16457 of the International Standardization Organization (ISO).
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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VISUALIZATION AND ONLINE TOOLS FOR SPACE
ENVIRONMENT PARAMETERS• Current time global NmF2, hmF2, and TEC IRI maps (S.-R. Zhang, MIT): http://madrigal.haystack.mit.edu/models/IRI/index.html
• Real-time maps of IRI TEC for Australiasia, North America, Europe, and Japan (IPS, Sydney, Australia): http://www.ips.gov.au/Satellite/2/1
• Computation of ionospheric conductivities using IRI and CIRA (WDC Kyoto, Japan): http://swdcwww.kugi.kyoto-u.ac.jp/ionocond/index.html
• MPEG movies of global maps of IRI density and temperature at the Space Environments Branch of NASA Glenn Research Center: http://powerweb.grc.nasa.gov/pvsee/info/movies/iri90.html
• The SPace ENVironment Information System (SPENVIS) developed at the Belgian Institute for Space Aeronomy for ESA/ESTEChttp://www.spenvis.oma.be/spenvis/
• IRIWeb for online computation and plotting of IRI parameters developed at NASA/GSFC NSSDC/SPDF http://modelweb.gsfc.nasa.gov/models/iri.html
3-d electron density visualization using AVS (CRL, Tokyo, Japan )
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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foF2 UT: 0 - 24 foF2 LT: 0 - 24
hmF2 UT: 0 - 24 log(Ne) UT: 0 - 24
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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BACKGROUND IONOSPHERE FOR EVALUATING DATA
RETRIEVAL TECHNIQUES
• Testing algorithms that convert GPS measurements into global TEC maps (Hernandez-Pajares et al., 2002)
• TEC from NNSS Doppler measurements (Ciraolo and Spalla, 2002) • Reliability of tomographic methods (Bust et al., 2004).
• Testing algorithm for GPS/MET occultation measurements (Tsai et al., JASTP, submitted; Hocke and Igarashi, 2002)
• Developing data analysis algorithm for retrieval of electron densities from TIMED/GUVI airglow measurements (DeMajistre et al., 2004)
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IONOSPHERIC CORRECTIONS FOR SINGLE-FREQUENCY
ALTIMETRY
• Pathfinder Project: Longtime data record of sea surface heights; updating IRI with ionosonde data (Bilitza, Bhardwaj and Koblinsky, 1997; Lillibridge and Cheney, 1997)
• ERS Quick-look data (ERS Products User Manual, 1996)
• Work with Geosat Follow On (GFO) data (Zhao et al., 2002.
Polar Gateways Meeting Barrow, Alaska, Jan 23-29, 2008
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IONOSPHERIC PARAMETERS FOR THEORETICAL MODELS
Comprehensive Ring Current Model (CRCM)[Ebihara, et al., 2004, 2005]
Ionospheric Conductances for Rice ConvectionModel (RCM) [DeZeeuw et al. 2004]
Baseline against which the predictive skills ofphysics-based models are compared [Siscoe et al., 2004]
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JGR/GRL/RS/JSTP/AG papers using IRI
IRI Usage Statistics
IRI ftp site downloads ~5,000/monthIRIweb online accesses ~4,000/month
2005: 51 2006: 54
Dec06: 6,058 Nov06: 4,772
Apr07: 4,470 May07:4,241
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