Radio Science

2011 Ionospheric Effects Symposium

Radio Science, vol. 47, no. 4, 2012

Guest Editor(s):J. Goodman

Description:The special section of Radio Science associated with the 2011 Ionospheric Effects Symposium (IES) will be focused on the ionospheric effects on radio propagation, including total electron content and scintillation effects, together with HF, VHF, and UHF propagation effects more generally. This will continue the long and successful special section series associated with IES.

    1. The effect of phase scintillations on the accuracy of phase screen simulation using deterministic screens derived from GPS and ALTAIR measurements

      Charles S. Carrano, Keith M. Groves and Ronald G. Caton

      Article first published online: 20 JUL 2012 | DOI: 10.1029/2011RS004958

      Key Points

      • Phase scintillation limits the accuracy of phase screen simulations
      • We quantify this accuracy by cross-correlating predicted and measured signals
      • Back-propagation techniques can improve this correlation
    2. Importance of data assimilation technique in defining the model drivers for the space weather specification of the high-latitude ionosphere

      L. Zhu, R. Schunk, L. Scherliess and V. Eccles

      Article first published online: 4 JUL 2012 | DOI: 10.1029/2011RS004936

      Key Points

      • Data assimilation technique is important for space weather
      • Empirical model cannot provide accurate weather features
      • Space weather ability of the global MHD is restricted by solar wind data
    3. Problems associated with uncertain parameters and missing physics for long-term ionosphere-thermosphere forecasting

      R. W. Schunk, L. Gardner, L. Scherliess and L. Zhu

      Article first published online: 19 JUN 2012 | DOI: 10.1029/2011RS004911

      Key Points

      • Missing physics in global models
      • Ionosphere-thermosphere model uncertainties
      • Problems for space weather forecasting
    4. Characteristics of traveling ionospheric disturbances observed by the TIDDBIT sounder

      G. Crowley and F. S. Rodrigues

      Article first published online: 9 JUN 2012 | DOI: 10.1029/2011RS004959

      Key Points

      • HF Doppler sounders obtain comprehensive TID characteristics on bottomside
      • TID azimuths and speeds suggest TIDs are filtered by thermospheric winds
      • TID azimuths in Virginia rotate opposite direction from those in Antarctic
    5. Sharpening our thinking about polar cap ionospheric patch morphology, research, and mitigation techniques

      Herbert C. Carlson

      Article first published online: 31 MAY 2012 | DOI: 10.1029/2011RS004946

      Key Points

      • Magnetic reconnection produces most patches
      • Scintillation is driven by shear, not gradient drift instability
      • Magnetic reconnection impacts satellite drag
    6. Simulating the impacts of ionospheric scintillation on L band SAR image formation

      Charles S. Carrano, Keith M. Groves and Ronald G. Caton

      Article first published online: 26 MAY 2012 | DOI: 10.1029/2011RS004956

      Key Points

      • Ionospheric scintillation degrades SAR imagery
      • We present a phase screen technique to predict this effect
      • We compare simulated and observed images from PALSAR
    7. Use of the Auroral Boundary Index for potential forecasting of ionospheric scintillation

      James M. Griffin, Thomas C. Connor and Hilary E. Snell

      Article first published online: 19 MAY 2012 | DOI: 10.1029/2011RS004954

      Key Points

      • Proxy Ap index based on ABI will have higher temporal resolution
      • Forecast of geomagnetic activity can be made using ABI-based Ap
      • Ionospheric models using ABI-based Ap can then be used in nowcast/forecast mode
    8. Global observations of L band scintillation at solar minimum made by COSMIC

      Kenneth F. Dymond

      Article first published online: 19 MAY 2012 | DOI: 10.1029/2011RS004931

      Key Points

      • Global observations of L band scintillation made using radio occultation (RO)
      • Viewing geometry causes RO measurements to be very sensitive to scintillation
      • RO can measure the 3-D distribution of ionospheric irregularities
    9. The Low-Latitude Ionosphere Sensor Network: Initial results

      C. E. Valladares and J. L. Chau

      Article first published online: 18 MAY 2012 | DOI: 10.1029/2011RS004978

      Key Points

      • Presents capabilities of a new distributed observatory
      • Gives longitudinal extension of midnight TEC enhancements
      • Uses TEC values from GPS stations in South America to measure GWs
    10. New Vary-Chap profile of the topside ionosphere electron density distribution for use with the IRI model and the GIRO real time data

      Patrick Nsumei, Bodo W. Reinisch, Xueqin Huang and Dieter Bilitza

      Article first published online: 17 MAY 2012 | DOI: 10.1029/2012RS004989

      Key Points

      • Topside electron density model for IRI and GIRO
      • Empirical electron density model using ISIS-2 data
      • New Vary-Chap profile representation
    11. Sounding of HF heating-induced artificial ionospheric disturbances by navigational satellite radio transmissions

      V. E. Kunitsyn, E. S. Andreeva, V. L. Frolov, G. P. Komrakov, M. O. Nazarenko and A. M. Padokhin

      Article first published online: 16 MAY 2012 | DOI: 10.1029/2011RS004957

      Key Points

      • Influence of HF heating-induced irregularities on navigational signals
      • Spectrum of TEC variations during heating experiments
      • Tomographic image of wave disturbances in ionosphere generated by HF heating
    12. Introducing a disturbance ionosphere index

      N. Jakowski, C. Borries and V. Wilken

      Article first published online: 8 MAY 2012 | DOI: 10.1029/2011RS004939

      Key Points

      • Definition of a disturbance ionosphere index based on GNSS measurements
      • Application demonstration of DIX on ionospheric response to solar flares
      • Application demonstration of DIX on medium- and large-scale perturbations
    13. HF propagation modeling within the polar ionosphere

      E. M. Warrington, N. Y. Zaalov, J. S. Naylor and A. J. Stocker

      Article first published online: 1 MAY 2012 | DOI: 10.1029/2011RS004909

      Key Points

      • Current propagation prediction methods inadequate in polar cap
      • Improved area coverage by taking into account presence of polar patches
      • Further improvements possible with inclusion of near-real-time data
    14. HiCIRF: A high-fidelity HF channel simulation

      L. J. Nickisch, Gavin St. John, Sergey V. Fridman, Mark A. Hausman and C. J. Coleman

      Article first published online: 26 APR 2012 | DOI: 10.1029/2011RS004928

      Key Points

      • A high-fidelity HF ionospheric channel simulation has been developed
      • The simulation includes HF multimode and small-scale scatter
      • The simulation generates pulse-by-pulse channel impulse response realizations
    15. Modeling the daytime, equatorial ionospheric ion densities associated with the observed, four-cell longitude patterns in E × B drift velocities

      Eduardo A. Araujo-Pradere, Tzu-Wei Fang, David N. Anderson, Mariangel Fedrizzi and Russell Stoneback

      Article first published online: 26 APR 2012 | DOI: 10.1029/2011RS004930

      Key Points

      • C/NOFS data to quantify the four-cell pattern
      • Modeling ion density at boundary conditions
      • Comparing calculated densities against observed ExB drift patterns
    16. Inversion of backscatter ionograms and TEC data for over-the-horizon radar

      Sergey V. Fridman, L. J. Nickisch and Mark Hausman

      Article first published online: 26 APR 2012 | DOI: 10.1029/2011RS004932

      Key Points

      • OTHR coordinate registration requires real-time ionosphere model
      • Ionospheric model supported by backscatter and vertical ionograms is useful
      • Ionospheric model is further improved by incorporating GPS TEC data
    17. Comparison of propagation predictions and measurements for midlatitude HF near-vertical incidence sky wave links at 5 MHz

      Marcus C. Walden

      Article first published online: 19 APR 2012 | DOI: 10.1029/2011RS004914

      Key Points

      • HF NVIS measurements and VOACAP/ASAPS predictions compared over 23 months
      • RMS differences between measurements and predictions show cyclical pattern
      • VOACAP and ASAPS generally overpredict median signal level for these NVIS links
    18. Excited spherical waves in unbounded cold magnetoplasma and applications in radio sounding

      Xueqin Huang and Bodo W. Reinisch

      Article first published online: 18 APR 2012 | DOI: 10.1029/2011RS004940

      Key Points

      • Spherical wave excitation in plasma
      • Rigorous solution for far field
    19. Further determinations of strong scintillation effects on GNSS signals using the Hybrid Scintillation Propagation Model

      Nikolay N. Zernov, Vadim E. Gherm and Hal J. Strangeways

      Article first published online: 17 APR 2012 | DOI: 10.1029/2011RS004935

      Key Points

      • Finding the variation of spectral indices with ionospheric scintillation level
      • Calculating cycle slip frequency as a function of amplitude scintillation index
      • Comparison of Hybrid Scintillation Propagation Model and equivalent phase screen
    20. Assimilation of GIRO data into a real-time IRI

      I. A. Galkin, B. W. Reinisch, X. Huang and D. Bilitza

      Article first published online: 17 APR 2012 | DOI: 10.1029/2011RS004952

      Key Points

      • Assimilating GIRO data in IRI allows accurate global ionospheric specification
      • Assimilative IRI adjusts coefficients of its empirical maps to match the data
      • Assimilation of low-latency GIRO data allows real-time IRI for space weather
    21. Typhoon Melor and ionospheric weather in the Asian sector: A case study

      D. D. Rice, J. J. Sojka, J. V. Eccles and R. W. Schunk

      Article first published online: 13 APR 2012 | DOI: 10.1029/2011RS004917

      Key Points

      • Significant F-region anomaly was observed following Typhoon Melor landfall
      • No geophysical cause was obvious; solar min conditions existed
      • Anomaly was seen in ionosonde and GAIM model results
    22. Imaging equatorial spread F irregularities with the São Luís coherent backscatter radar interferometer

      F. S. Rodrigues, A. O. Moraes and E. R. de Paula

      Article first published online: 30 MAR 2012 | DOI: 10.1029/2011RS004929

      Key Points

      • New in-beam images of ESF structures in the Brazilian sector are presented
      • Scattering structures causing distinct types of ESF echoes are presented
      • Images are discussed in terms of ESF theories and independent observations
    23. Improving the automatic inversion of digital Alouette/ISIS ionogram reflection traces into topside electron density profiles

      Robert F. Benson, Vladimir Truhlik, Xueqin Huang, Yongli Wang and Dieter Bilitza

      Article first published online: 30 MAR 2012 | DOI: 10.1029/2011RS004963

      Key Points

      • Topside ionospheric solar cycle variations
      • Improved automatic inversion of ISIS topside ionogram traces is needed
      • Improve the quality of topside ISIS digital ionograms and their inversion
    24. A new technique for spectral analysis of ionospheric TEC fluctuations observed with the Very Large Array VHF system: From QP echoes to MSTIDs

      J. F. Helmboldt, T. J. W. Lazio, H. T. Intema and K. F. Dymond

      Article first published online: 18 FEB 2012 | DOI: 10.1029/2011RS004787

      Key Points

      • We have shown that the VLA can detect TEC fluctuations </=0.001 TECU
      • The VLA can observe medium (~100 km) and small (~few km) waves simultaneously
      • We have detected the direction dependent E-F coupling instability with the VLA