Attenuation of GPS scintillation in Brazil due to magnetic storms
|
|
- Annis Cannon
- 5 years ago
- Views:
Transcription
1 SPACE WEATHER, VOL. 6,, doi: /2006sw000285, 2008 Attenuation of GPS scintillation in Brazil due to magnetic storms E. Bonelli 1 Received 21 September 2006; revised 15 June 2008; accepted 16 June 2008; published 4 September [1] Amplitude scintillations in satellite signals can cause errors in communications, because of signal fading, but can be very useful for scientists trying to improve their understanding of the physics of the ionosphere. Usually, magnetic storms are expected to affect the ionosphere in such way as to increase ionospheric irregularities responsible for scintillations. To help change the view of scientists and engineers, in this respect, we show that amplitude scintillation on GPS signals show dramatic decrease during selected magnetic storms, at Brazilian GPS stations. These stations are located on magnetic latitudes that go from equatorial (São Luís) to low-latitude (São José dos Campos and Cachoeira Paulista) so that a region of several thousand kilometers is represented by the data. We present 4 months of data chosen from 2003 to 2005 to represent the strongest storms during each scintillation season. Although there is lack of data for some days from the different stations, it is possible to see, especially for the Halloween Storm (October 2003), that scintillations are attenuated in this wide range of latitudes. During magnetically calm periods scintillations are strong, in this region, from August to March, during solar maxima. Although the data are clear about the attenuation of scintillations during greater magnetic storms, it is not possible to easily conclude which physical mechanism was responsible for this phenomenon, even with the aid of more detailed data like Dst and AE. Citation: Bonelli, E. (2008), Attenuation of GPS scintillation in Brazil due to magnetic storms, Space Weather, 6,, doi: /2006sw Introduction [2] The Natal GPS station is located at 5.84 S and W, geographic coordinates. The magnetic declination by the end of 2003 was 22 and the magnetic dip was 21.6, which corresponds to magnetic latitude (dip latitude) of 10. For Natal, the dip angle has being changing by about 1 every 3 years, since 1945, when it was located at the magnetic equator. Other Brazilian stations considered in this paper are, from low-magnetic to midmagnetic latitudes: Manaus (+5 ), São Luís ( 1.5 ), and São José dos Campos ( 17 ). The numbers in the parenthesis indicate their approximate dip latitudes, or magnetic latitudes. The local time for Manaus is UT minus 4 h, while for the other stations it is UT minus 3 h. The GPS scintillations were obtained using the L1 frequency (1.575 GHz). It is known that, at this frequency, the signal is most sensitive to irregularities, at zenith, of scale size around 400 m [Yeh and Liu, 1982; Kintner et al., 2001]. The scintillation index, S 4, used to measure the effects of ionospheric irregularities on the signal is defined as the dispersion of power divided by 1 Departmento de Física, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil. average power [Briggs and Parkin, 1963]. The method used in analyzing the data is to calculate an average S 4 index for all available satellites, for the night period, and compare it with the sum of 3-h K p indices for several hours before sunset. The data include four major storms for which we had simultaneous scintillation data. In Natal the scintillation season goes from August to April, because of both the inclination of the axis of the earth with respect to the ecliptic and to the declination of the geomagnetic field. During this period of months, the sunset at both hemispheres occur at the extremities of the same field lines, so dynamo electric fields across magnetic field lines in one hemisphere cannot be shorted out in the other hemisphere, as it would be if one end of the field lines were in the dark and the other still in sunshine, immersed in high conducting plasma. 2. Data Analysis [3] The scintillation data is obtained at a rate of 50 samples per second for each available satellite. Further data processing produces the scintillation index, S 4, per Copyright 2008 by the American Geophysical Union 1of9
2 Figure 1. Scintillations for October 2003 for satellites passing near the zenith at Natal. For each section the same satellite is represented, for the consecutive nights, with 5 min delay on 29 October. The magnetically calm day is represented by the black line and the disturbed day by the gray line. Note that there are no data gaps for either day, for any of the satellites and day. minute of data, along with 1 min averages of wide band power and narrow band power, for each satellite. [4] To summarize a whole night of scintillations we averaged the 1 min S 4 for all satellites present at that night, from 2100 (near local sunset) to 0600 UT. This average will be referred to as hs 4 i. The number of points used in the computation of hs 4 i shows whether all satellites are well represented in the average. This number lies, in general, between 1000 and 2000 points. [5] To represent the magnetic activity, we use the sum of K p from 0000 to 1800 LT, which will be denoted by P K p. The reason for choosing this time interval for K p is that we plan to forecast GPS scintillations, so that at sunset we could be able to know how much scintillations should be expected at night. For the same reason, we used real-time estimates of K p, from the magnetic data from stations around the world ( [6] To try to have a more detailed understanding, of what was observed in the above gross average of K p we add also plots of estimated D st and measured AE indexes. The AE indexes are those from World Data Center-Kyoto ( The estimated D st index ( dsttemerin/dsttemerin.html) is a real-time index, toward which the Kyoto values converge when they become definitive, after some years. 3. Results and Discussion [7] During strong storms, amplitude scintillation might become so intense that the GPS receiver could lose the lock to one or more satellites. This effect is very rare in Natal. Sometimes there is loss of lock onto satellites, but this happens more often during daytime. To show that track is kept of all satellites, during strong scintillations we show (Figure 1), the strong scintillations of 28 October 2003 (in black), superposed to the weak scintillations of 29 October 2003 (in gray) for Natal. The satellites chosen are those that passed near the zenith. From one night to the next, the time a satellite moves into view is about 5 min latter than for the previous day. The path in the sky is the same for both days. In Figure 1, it is clear that the satellites were kept track of during the strong scintillations. Actually, the main result, for this paper, is the gray plot, where scintillations are very weak and a satellite could not be lost because of it. [8] To see the behavior of GPS scintillations during magnetic storms we plot hs 4 i and P K p versus day for each month of data available. We chose months with strong storms and with less days with missing scintillation data. Since the beginning of the GPS era, there were few strong storms and we missed some, so that we present below only four major storms. In what follows, the word storm corresponds to a day or to consecutive days with high P K p, even if there were more than one superposed storms, in terms of D st. Since we are summing up several 3-h K P indices, it is convenient to define what we understand for a high K p sum: a high P K p is considered to be above 24, meaning that the mean 3-h index is about 4, since K p greater than 3+ is supposed to represent disturbed 2of9
3 Figure 2. Average S 4 for October 2003 for Natal and Manaus and P (K p ) versus day. conditions. In the text below, whenever we mention latitude we refer to the magnetic latitude. A word about São José dos Campos and Cachoeira Paulista. These two stations are very close so that they have approximately the same magnetic dip and declination. This allows us to use data from Cachoeira Paulista, when those of São José dos Campos are missing for a given day. When data from both stations are present, São José dos Campos data are plotted The 2003 Halloween Storm [9] The strongest storm from 2003 to 2005, the Halloween storm, occurred in the period of October 2003 (Figures 2-- 4). In Figures 2-- 4, we see that during the 4 days preceding the the onset of the storm, P K p was low, as compared to the storm days. [10] On the storm days, October, there was a dramatic decrease of hs 4 i for Manaus (Figure 2), São Luís (Figure 3), and Natal. On the other hand, although in São José dos Campos (SJC) and Cachoeira Paulista (Figure 4) there was a decrease in scintillations, this decrease was not as abrupt as in the low-latitude stations. In Figure 1, we show details of the wide band power for satellites that passed near the zenith in the first night during the storm (gray line) and in the previous night (black line). It is very clear that scintillations almost disappeared during the storm, for Natal. [11] The strong scintillation, for 28 October can be attributed to the usual quiet day behavior, at these stations. On the 29 October, both Dst (Figure 5) and AE (Figure 6) show the beginning of a storm, and scintillation diminishes. In this case the absence of scintillation could mean either a washout of the plasma, due to previous strong eastward electric field, due to instant penetration from the auroral zone or a stabilization of the ionosphere due to a strong disturbed dynamo, since the auroral storm occurred several hours before. [12] After the storm, hs 4 i remains low at the beginning of November (see also Figure 7), although P K p is Figure 3. Average S 4 for October 2003 for Natal and São Luís and P K p versus day. 3of9
4 Figure 4. Average S 4 for October 2003 for Natal and São José dos Campos and Cachoeira and P K p versus day. moderate. Would this mean that the effect of the disturbed period may remain for some days? In this case, the responsible mechanism could be the disturbance dynamo. Actually, a strong auroral storm occurred in the evening of 30 October, as shown in the AE plot (Figure 6), and it is possible that it would have caused the attenuation of scintillation on 1 November. [13] For this period, there is data from other stations [Basu et al., 2005] for scintillations of a geostationary satellite, at 250 MHz. We shall come back to this in the discussion section November 2003 [14] For this month, only 1 day (20 November) stands out from the others, in P K p, although not by much, and we considered it as a magnetically disturbed day (Figure 7). Even for this situation of a short-duration storm, the decrease in hs 4 i is very clear both for Natal, São José dos Campos, and Manaus. Although data for São Luís were not available for this day, we see that the behavior was the same at all latitudes. São José already had weak scintillations when the storm occurred, however, it dropped even further and did not recover before 4 days, unlike Natal and Manaus, which recovered in the next day. The Manaus data was plotted only around 23 November, which is the important day for our reasoning. [15] Analyzing the more detailed behavior of Dst (Figure 8) and AE (Figure 9), for days , we see that there was a broad maximum of auroral activity during 20 November, while the main phase of the storm ended in the afternoon (Natal local time is UT minus 3 h) of 21 November. In this case it is more reasonable to assume that the inhibition of scintillation was due to a disturbance dynamo westward electric field October 2004 [16] For this month, the maximum of P K p occurred on 13 October with a second maximum on 14 October (Figure 10). This was the mildest storm of all data presented ( P K p 30) and, despite that, there is a pronounced valley in the scintillations of São Luís and Natal, for these days. São José dos Campos scintillations were not affected by this storm. There is no data for Manaus for this period. [17] The Dst data (Figure 11) present two superposed storms. The first starts on the 12 October, by midnight, its main phase ending around noon on the 13 October. In this case, at local sunset, on the 13 October, where the first inhibition of scintillation occurred, the storm, as viewed through Dst, was already in the recovery phase. Usually, in Figure 5. Estimated Dst versus time for October of9
5 Figure 6. AE index versus time for October this case, scintillation increases, but this did not happen. To understand what caused the attenuation of scintillation, let us turn to the behavior of the auroral region, represented by the AE index (Figure 12). AE peaked around noon, on the 13 October, and the disturbance dynamo could be the responsible for the diminution of scintillation. This last explanation also applies to 14 October, since AE has a second peak around noon, again, on this day January 2005 [18] Here we have a relatively strong storm which occurred from days 17 to 19, and a minor one from 21 to 22 (Figure 13). The reduction of average S 4 are apparent for Natal and São Luís. At this time of the year, scintillations were weak in São José dos Campos, especially at this time, near the coming solar minimum. Note the increase in scintillations, for 1 day only, in all three stations, when the average K p fell between this large storm and a smaller one. Natal and São Luís seemed to respond to this second storm, too. [19] Regarding the analysis of the behavior of the indexes Dst (Figure 14) and AE (Figure 15) we see that while Dst did not reach very negative values, the auroral zone was very stormy, with many peaks of activity. Attenuation of scintillations could be due to disturbed dynamo, due to any peak in activity, during the day. With respect to 16 January, there was some scintillation since both indexes indicated a quiet time and then, the normal prereversal eastward electric field was the main driver of upward plasma drifts. 4. Discussion and Conclusions [20] Although there is indication [Basu et al., 2001] that magnetic storms can either enhance or inhibit the formation of ionospheric irregularities responsible for scintillations, the results shown here indicate that for the four selected major storms the inhibition always occur be it because of prompt penetration of westward electric field, due to disturbance dynamo, or due to a wash out of the plasma. [21] Detailed analysis, as done in the reference above, and references therein, are very important to show how prompt penetration electric fields [Scherliess and Fejer, 1997] and disturbance dynamo fields [Fejer and Scherliess, 1997] might control the formation of the irregularities. In this work, however, all conclusions seemed to lead to the disturbance dynamo interpretation of the scintillations. One must be careful, since the auroral behavior, shown by AE, seems to explain, also, the attenuation of scintillations during the Halloween storm, when the ionosphere Figure P 7. Average S 4 for November 2003 for Natal and São José dos Campos and Manaus and Kp versus day. 5of9
6 Figure 8. Estimated Dst versus time for November could have been washed out because of a strong eastward electric field. [22] Using 250 MHz scintillation data from a geostationary satellite, whose name is not mentioned by the authors, from 4 stations, [Basu et al., 2005] suggested that there is a connection between the time of the penetration of electric fields from high latitudes and the time of local sunset. For this reason, 3 stations had scintillations because they fulfilled the sunset requirement. Actually, 2 stations had this behavior, since one of them was near or inside the storm expanding aurora oval. The Brazilian stations considered here, however, had the same storm behavior as the fourth station, Ancon, i.e., no scintillation. For Natal, the sunset time suggests it should be affected, especially on 31 October, when the penetration occurred during the time of local sunset. The other stations of this paper, Manaus, São Luís e SJC are reasonably close to Natal, in latitude, to be considered equivalent, in terms of sunset time. In fact, they behave in a very similar fashion regarding the behavior of scintillations during the magnetic storms that were considered here. With regards to VHF scintillations, it is known, since 1983, that they are also attenuated during magnetic storms in Natal [Medeiros et al., 1983]. [23] Using L-band scintillations from a geostationary satellite [Groves et al., 1997], showed that at Ascension Island (dip latitude 15 ) scintillations suffered more attenuation as the K p index got higher. Considering these two cases of attenuation, in L-Band and VHF, which occurred a long time ago, in terms of the variation of dip angle and declination in the region, it is conforting to know that the the same physics seems to be in action, meaning that recent results are similar to the ones of some years ago. To detect a variation of the dependence of the phenomenon with the geomagnetic field variation in the region, one would have to go further back in time. That would be one of our next tasks since, in Natal, VHF scintillation data is available since [24] The 4 months of scintillation data presented do not represent the whole period of important storms from October 2003 to January In order to show that, despite this, the conclusions are of significance, let us discuss the strong storms for which there was no scintillation data at Natal, this station being the guide on what dates to select from this and from the other stations. In July 2004, there was a strong storm. This time of the year, however, is outside the scintillation season for the Brazilian stations, which starts in August and ends in April, as explained in the introduction. The other missing period is the one corresponding to storm(s) that occurred from days November in This was an important period at the center of the scintillation season, and it is unfortunate that we have no scintillation data, in Natal, for that period. On the overall, there were six important periods of storms, during the data spam, of which we have presented data for four of them, but the July 2004 storm should not count, since there would be no scintillations to register. For this reason, we have scintillation data for most of the important storms from 2003 to 2005, which means that the results above should repeat for the coming storms, outside solar minima. A continuation of this work will be the analysis of the solar minimum behavior of scintillations during magnetic storms. In this case, only Natal, São Luís and Manaus should exhibit scintillations. [25] Works about GPS scintillations in São Luís and Cachoeira Paulista make only brief comments about storm effects [e.g, Kil et al., 2000; Rodrigues et al., 2004]. Figure 9. AE index versus time for November of9
7 Figure 10. Average S 4 for October 2004 for Natal and São José dos Campos and São Luís and P K p versus day. Figure 11. Estimated Dst versus time for October Figure 12. AE index versus time for October of9
8 Figure 13. Average S 4 for January 2005 for Natal and São Luís and São José dos Campos and P K p versus day. Figure 14. Estimated Dst versus time for January Figure 15. AE index versus time for January of9
9 [26] Acknowledgments. The GPS card and antennae were kindly donated by Cornell University, through Dr. Paul Kintner of the Department of Electrical Engineering in He is also responsible for the Brazilian net of observatories, coordinated nationwide by Dr. Eurico Rodrigues de Paula to whom I am greatly indebted for providing the data for stations other than Natal. I also thank Dr. Theodore Lyman Beach for the software to collect and treat the data. This work has been supported by continuous grants from the FAPERN/ Rio Grande do Norte and CNPq Brazilian agencies. References Basu, S., et al. (2001), Ionospheric effects of major magnetic storms during the International Space Weather Period of September and October 1999: GPS observations, VHF/UHF scintillations, and in situ density structures at mid and equatorial latitudes, J. Geophys. Res., 106, 30, ,413. Basu, S., S. Basu, K. M. Groves, E. MacKenzie, M. J. Keskinen, and F. Rich (2005), Near-simultaneous plasma structuring in the midlatitude and equatorial ionosphere during magnetic superstorms, Geophys. Res. Lett., 32, L12S05, doi: /2004gl Briggs, T. L., and I. A. Parkin (1963), On the variation of radio star and satellite scintillations with zenith angle, J. Atmos. Terr. Phys., 25, Fejer, B. G., and L. Scherliess (1997), Empirical models of storm time equatorial zonal electric fields, J. Geophys. Res., 102, 24, ,056. Groves, K. M., et al. (1997), Equatorial scintillation and systems support, Radio Sci., 32(5), Kil, H., P. M. Kintner, E. R. de Paula, and I. J. Kantor (2000), Global Positioning System measurements of the ionospheric zonal apparent velocity at Cachoeira Paulista in Brazil, J. Geophys. Res., 105(A3), Kintner, P. M., H. Kil, T. L. Beach, and E. R. Paula (2001), Fading timescales associated with GPS signals and potential consequences, Radio Sci., 36(4), Medeiros, R. T. D., M. A. Abdu, and I. J. Kantor (1983), A comparative study of VHF scintillation and spread F events over Natal and Fortaleza in Brazil, J. Geophys. Res., 88(A8), Rodrigues, F. S., E. R. de Paula, M. A. Abdu, A. C. Jardim, K. N. Iyer, P. M. Kintner, and D. L. Hysell (2004), Equatorial spread F irregularity characteristics over São Luís, Brazil, using VHF radar and GPS scintillation techniques, Radio Sci., 39, RS1S31, doi: / 2002RS Scherliess,L.,andB.G.Fejer(1997),Stormtimedependenceof equatorial disturbance dynamo zonal electric fields, J. Geophys. Res., 102, 24, ,046. Yeh, K. C., and C. H. Liu (1982), Radio wave scintillations in the ionosphere, Proc. IEEE, 70(4), E. Bonelli, Departmento de Física, Universidade Federal do Rio Grande do Norte, Natal, RN , Brazil. (bonelli@ponta-negra. com) 9of9
Characteristics of the ionospheric irregularities over Brazilian longitudinal sector
Characteristics of the ionospheric irregularities over Brazilian longitudinal sector E. R. de Paula 1, E. A. Kherani 1, M. A. Abdu 1, I. S. Batista 1, J. H. A. Sobral 1, I. J. Kantor 1, H. Takahashi 1,
More informationStudy of the Ionosphere Irregularities Caused by Space Weather Activity on the Base of GNSS Measurements
Study of the Ionosphere Irregularities Caused by Space Weather Activity on the Base of GNSS Measurements Iu. Cherniak 1, I. Zakharenkova 1,2, A. Krankowski 1 1 Space Radio Research Center,, University
More informationEquatorial bubbles as observed with GPS measurements over Pune, India
RADIO SCIENCE, VOL. 41,, doi:10.1029/2005rs003359, 2006 Equatorial bubbles as observed with GPS measurements over Pune, India A. DasGupta, 1,2 A. Paul, 2 S. Ray, 1 A. Das, 1 and S. Ananthakrishnan 3 Received
More informationMulti-technique investigations of storm-time ionospheric irregularities over the São Luís equatorial station in Brazil
Annales Geophysicae (2004) 22: 3513 3522 SRef-ID: 1432-0576/ag/2004-22-3513 European Geosciences Union 2004 Annales Geophysicae Multi-technique investigations of storm-time ionospheric irregularities over
More informationEffect of Magnetic activity on scintillation at Equatorial Region during Low Solar Activity
Effect of Magnetic activity on scintillation at Equatorial Region during Low Solar Activity Sunita Tiwari*, Shivalika Sarkar, Asha Vishwakarma and A. K. Gwal Space Science Laboratory, Department of Physics,
More informationEFFECTS OF SCINTILLATIONS IN GNSS OPERATION
- - EFFECTS OF SCINTILLATIONS IN GNSS OPERATION Y. Béniguel, J-P Adam IEEA, Courbevoie, France - 2 -. Introduction At altitudes above about 8 km, molecular and atomic constituents of the Earth s atmosphere
More informationChapter 2 Analysis of Polar Ionospheric Scintillation Characteristics Based on GPS Data
Chapter 2 Analysis of Polar Ionospheric Scintillation Characteristics Based on GPS Data Lijing Pan and Ping Yin Abstract Ionospheric scintillation is one of the important factors that affect the performance
More informationOn the response of the equatorial and low latitude ionospheric regions in the Indian sector to the large magnetic disturbance of 29 October 2003
Ann. Geophys., 27, 2539 2544, 2009 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Annales Geophysicae On the response of the equatorial and low latitude ionospheric
More informationMultistation digisonde observations of equatorial spread F in South America
Annales Geophysicae (2004) 22: 3145 3153 SRef-ID: 1432-0576/ag/2004-22-3145 European Geosciences Union 2004 Annales Geophysicae Multistation digisonde observations of equatorial spread F in South America
More informationVHF radar observations of the dip equatorial E-region during sunset in the Brazilian sector
Ann. Geophys., 24, 1617 1623, 2006 European Geosciences Union 2006 Annales Geophysicae VHF radar observations of the dip equatorial E-region during sunset in the Brazilian sector C. M. Denardini, M. A.
More informationThe low latitude ionospheric effects of the April 2000 magnetic storm near the longitude 120 E
Earth Planets Space, 56, 67 612, 24 The low latitude ionospheric effects of the April 2 magnetic storm near the longitude 12 E Libo Liu 1, Weixing Wan 1,C.C.Lee 2, Baiqi Ning 1, and J. Y. Liu 2 1 Institute
More informationScientific Studies of the High-Latitude Ionosphere with the Ionosphere Dynamics and ElectroDynamics - Data Assimilation (IDED-DA) Model
DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Scientific Studies of the High-Latitude Ionosphere with the Ionosphere Dynamics and ElectroDynamics - Data Assimilation
More information1. Terrestrial propagation
Rec. ITU-R P.844-1 1 RECOMMENDATION ITU-R P.844-1 * IONOSPHERIC FACTORS AFFECTING FREQUENCY SHARING IN THE VHF AND UHF BANDS (30 MHz-3 GHz) (Question ITU-R 218/3) (1992-1994) Rec. ITU-R PI.844-1 The ITU
More informationStudy of small scale plasma irregularities. Đorđe Stevanović
Study of small scale plasma irregularities in the ionosphere Đorđe Stevanović Overview 1. Global Navigation Satellite Systems 2. Space weather 3. Ionosphere and its effects 4. Case study a. Instruments
More informationInvestigation of height gradient in vertical plasma drift at equatorial ionosphere using multifrequency HF Doppler radar
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109,, doi:10.1029/2004ja010641, 2004 Investigation of height gradient in vertical plasma drift at equatorial ionosphere using multifrequency HF Doppler radar S. R.
More informationUnderstanding the unique equatorial electrodynamics in the African Sector
Understanding the unique equatorial electrodynamics in the African Sector Endawoke Yizengaw, Keith Groves, Tim Fuller-Rowell, Anthea Coster Science Background Satellite observations (see Figure 1) show
More informationObservation of Scintillation Events from GPS and NavIC (IRNSS) Measurements at Bangalore Region
Observation of Scintillation Events from GPS and NavIC (IRNSS) Measurements at Bangalore Region Manjula T R 1, Raju Garudachar 2 Department of Electronics and communication SET, Jain University, Bangalore
More informationResponses of ionospheric fof2 to geomagnetic activities in Hainan
Advances in Space Research xxx (2007) xxx xxx www.elsevier.com/locate/asr Responses of ionospheric fof2 to geomagnetic activities in Hainan X. Wang a, *, J.K. Shi a, G.J. Wang a, G.A. Zherebtsov b, O.M.
More informationJOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, A03301, doi: /2009ja014788, 2010
Click Here for Full Article JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115,, doi:10.1029/2009ja014788, 2010 Scintillation producing Fresnel scale irregularities associated with the regions of steepest TEC gradients
More information[titlelscientific Studies of the High-Latitude Ionosphere with the Ionosphere Dynamics and Electrodynamics-Data Assimilation (IDED-DA) Model
[titlelscientific Studies of the High-Latitude Ionosphere with the Ionosphere Dynamics and Electrodynamics-Data Assimilation (IDED-DA) Model [awardnumberl]n00014-13-l-0267 [awardnumber2] [awardnumbermore]
More informationSignatures of ultra fast Kelvin waves in the equatorial middle atmosphere and ionosphere
GEOPHYSICAL RESEARCH LETTERS, VOL. 34, L11108, doi:10.1029/2007gl029612, 2007 Signatures of ultra fast Kelvin waves in the equatorial middle atmosphere and ionosphere H. Takahashi, 1 C. M. Wrasse, 2 J.
More informationExtreme solar EUV flares and ICMEs and resultant extreme ionospheric effects: Comparison of the Halloween 2003 and the Bastille Day events
RADIO SCIENCE, VOL. 41,, doi:10.1029/2005rs003331, 2006 Extreme solar EUV flares and ICMEs and resultant extreme ionospheric effects: Comparison of the Halloween 2003 and the Bastille Day events B. T.
More informationVHF and L-band scintillation characteristics over an Indian low latitude station, Waltair (17.7 N, 83.3 E)
Annales Geophysicae, 23, 2457 2464, 2005 SRef-ID: 1432-0576/ag/2005-23-2457 European Geosciences Union 2005 Annales Geophysicae VHF and L-band scintillation characteristics over an Indian low latitude
More informationMapping and Survey of Plasma Bubbles over Brazilian Territory
THE JOURNAL OF NAVIGATION (2007), 60, 69 81. f The Royal Institute of Navigation doi:10.1017/s0373463307004006 Printed in the United Kingdom Mapping and Survey of Plasma Bubbles over Brazilian Territory
More informationEighth International Congress of The Brazilian Geophysical Society. Copyright 2003, SBGf - Sociedade Brasileira de Geofísica
Pi1B pulsations at the South American equatorial zone during the 29 October 1994 magnetic storm Antonio L. Padilha*, M. Virginia Alves, Nalin B. Trivedi, INPE, Brazil Tai-I. Kitamura, Manabu Shinohara,
More informationAnalysis and Modeling of Mid-Latitude Decameter-Scale Plasma Wave Irregularities Utilizing GPS and Radar Observations
Analysis and Modeling of Mid-Latitude Decameter-Scale Plasma Wave Irregularities Utilizing GPS and Radar Observations A. Eltrass 1, W. A. Scales 1, P. J. Erickson 2, J. M. Ruohoniemi 1, J. B. H. Baker
More informationThe Effect of Geomagnetic Storm in the Ionosphere using N-h Profiles.
The Effect of Geomagnetic Storm in the Ionosphere using N-h Profiles. J.C. Morka * ; D.N. Nwachuku; and D.A. Ogwu. Physics Department, College of Education, Agbor, Nigeria E-mail: johnmorka84@gmail.com
More informationMulti-Technique Studies of Ionospheric Plasma Structuring
Multi-Technique Studies of Ionospheric Plasma Structuring Sunanda Basu Center for Space Physics Boston University 725 Commonwealth Avenue Boston, MA 02215 phone: (202) 404-1290 fax: (202) 767-9388 email:
More informationStudy of a coincident observation between the ROCSAT-1 density irregularity and Ascension Island scintillation
RADIO SCIENCE, VOL. 47,, doi:10.1029/2011rs004908, 2012 Study of a coincident observation between the ROCSAT-1 density irregularity and Ascension Island scintillation Y. H. Liu, 1 C. K. Chao, 2 S.-Y. Su,
More informationROTI Maps: a new IGS s ionospheric product characterizing the ionospheric irregularities occurrence
3-7 July 2017 ROTI Maps: a new IGS s ionospheric product characterizing the ionospheric irregularities occurrence Iurii Cherniak Andrzej Krankowski Irina Zakharenkova Space Radio-Diagnostic Research Center,
More information3-2-9 A Storm-Time Super Bubble as Observed with Dense GPS Receiver Network at East Asian Longitudes
3-2-9 A Storm-Time Super Bubble as Observed with Dense GPS Receiver Network at East Asian Longitudes A post sunset plasma bubble manifested by TEC depletion was observed at midlatitudes (~30 34 N, ~130
More informationA Beginner s Guide to Space Weather and GPS Updated February 21, 2008 Professor Paul M. Kintner, Jr. with acknowledgements to
A Beginner s Guide to Space Weather and GPS Updated February 1, 008 Professor Paul M. Kintner, Jr. with acknowledgements to M. Psiaki, T. Humphreys, A. Cerruti, B. Ledvina, A. Mannucci, D. Gary, E. de
More informationAnalysis of equatorial ionospheric irregularities based on a two high rate GNSS station setup
Analysis of equatorial ionospheric irregularities based on a two high rate GNSS station setup Jens Berdermann 1,Norbert Jakowski 1, Martin Kriegel 1, Hiroatsu Sato 1, Volker Wilken 1, Stefan Gewies 1,
More informationEffects of the major geomagnetic storms of October 2003 on the equatorial and low-latitude F region in two longitudinal sectors
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 110,, doi:10.1029/2004ja010999, 2005 Effects of the major geomagnetic storms of October 2003 on the equatorial and low-latitude F region in two longitudinal sectors
More informationMonitoring the polar cap/ auroral ionosphere: Industrial applications. P. T. Jayachandran Physics Department University of New Brunswick Fredericton
Monitoring the polar cap/ auroral ionosphere: Industrial applications P. T. Jayachandran Physics Department University of New Brunswick Fredericton Outline Ionosphere and its effects on modern and old
More informationEffects of geomagnetic storm on GPS ionospheric scintillations at Sanya
Journal of Atmospheric and Solar-Terrestrial Physics 70 (2008) 1034 1045 www.elsevier.com/locate/jastp Effects of geomagnetic storm on GPS ionospheric scintillations at Sanya Guozhu Li a,, Baiqi Ning a,
More informationRELATIONS BETWEEN THE EQUATORIAL VERTICAL DRIFTS, ELECTROJET, GPS-TEC AND SCINTILLATION DURING THE SOLAR MINIMUM
RELATIONS BETWEEN THE EQUATORIAL VERTICAL DRIFTS, ELECTROJET, GPS-TEC AND SCINTILLATION DURING THE 2008-09 SOLAR MINIMUM Sovit Khadka 1, 2, Cesar Valladares 2, Rezy Pradipta 2, Edgardo Pacheco 3, and Percy
More informationLatitudinal variations of TEC over Europe obtained from GPS observations
Annales Geophysicae (24) 22: 45 415 European Geosciences Union 24 Annales Geophysicae Latitudinal variations of TEC over Europe obtained from GPS observations P. Wielgosz 1,3, L. W. Baran 1, I. I. Shagimuratov
More informationSatellite Navigation Science and Technology for Africa. 23 March - 9 April, The African Ionosphere
2025-28 Satellite Navigation Science and Technology for Africa 23 March - 9 April, 2009 The African Ionosphere Radicella Sandro Maria Abdus Salam Intern. Centre For Theoretical Physics Aeronomy and Radiopropagation
More informationVertical group and phase velocities of ionospheric waves derived from the MU radar
Click Here for Full Article Vertical group and phase velocities of ionospheric waves derived from the MU radar J. Y. Liu, 1,2 C. C. Hsiao, 1,6 C. H. Liu, 1 M. Yamamoto, 3 S. Fukao, 3 H. Y. Lue, 4 and F.
More informationSTORM-TIME VARIATIONS OF ELECTRON TitleCONCENTRATION IN THE EQUATORIAL TOP IONOSPHERE.
STORM-TME VARATONS OF ELECTRON TitleCONCENTRATON N THE EQUATORAL TOP ONOSPHERE Author(s) NOUE, Takayoshi; CHO, Tegil Citation Contributions of the Geophysical n (197), : 9-7 ssue Date 197- URL http://hdl.handle.net/33/17
More informationEffects of magnetic storms on GPS signals
Effects of magnetic storms on GPS signals Andreja Sušnik Supervisor: doc.dr. Biagio Forte Outline 1. Background - GPS system - Ionosphere 2. Ionospheric Scintillations 3. Experimental data 4. Conclusions
More informationAssimilation Ionosphere Model
Assimilation Ionosphere Model Robert W. Schunk Space Environment Corporation 399 North Main, Suite 325 Logan, UT 84321 phone: (435) 752-6567 fax: (435) 752-6687 email: schunk@spacenv.com Award #: N00014-98-C-0085
More informationLEO GPS Measurements to Study the Topside Ionospheric Irregularities
LEO GPS Measurements to Study the Topside Ionospheric Irregularities Irina Zakharenkova and Elvira Astafyeva 1 Institut de Physique du Globe de Paris, Paris Sorbonne Cité, Univ. Paris Diderot, UMR CNRS
More informationModeling the ionospheric response to the 28 October 2003 solar flare due to coupling with the thermosphere
RADIO SCIENCE, VOL. 44,, doi:10.1029/2008rs004081, 2009 Modeling the ionospheric response to the 28 October 2003 solar flare due to coupling with the thermosphere David J. Pawlowski 1 and Aaron J. Ridley
More informationSTUDY OF GPS BASED IONOSPHERIC SCINTILLATION AND ITS EFFECTS ON DUAL FREQUENCY RECEIVER
Bhattacharya/Journal of Engineering, Science and Management Education/Vol. 1, 2010/55-61 STUDY OF GPS BASED IONOSPHERIC SCINTILLATION AND ITS EFFECTS ON DUAL FREQUENCY RECEIVER Soumi Bhattacharya *, P.K.Purohit
More informationIONOSPHERIC IRREGULARITIES PREDICTIONS AND PLUMES CHARACTERIZATION FOR SATELLITE
AFRL-OSR-VA-TR-2014-0082 IONOSPHERIC IRREGULARITIES PREDICTIONS AND PLUMES CHARACTERIZATION FOR SATELLITE Eurico De Paula FUNCATE - FUNDACACAO DE CIENCIAS 03/14/2014 Final Report DISTRIBUTION A: Distribution
More informationSignature of the 29 March 2006 eclipse on the ionosphere over an equatorial station
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 112,, doi:10.1029/2006ja012197, 2007 Signature of the 29 March 2006 eclipse on the ionosphere over an equatorial station J. O. Adeniyi, 1,2 S. M. Radicella, 1 I. A.
More informationRADIO SCIENCE, VOL. 42, RS4005, doi: /2006rs003611, 2007
Click Here for Full Article RADIO SCIENCE, VOL. 42,, doi:10.1029/2006rs003611, 2007 Effect of geomagnetic activity on the channel scattering functions of HF signals propagating in the region of the midlatitude
More informationSpecification and Forecasting of Outages on Satellite Communication and Navigation Systems
Specification and Forecasting of Outages on Satellite Communication and Navigation Systems S. Basu and K. M. Groves Space Vehicles Directorate, Air Force Research Laboratory, 29 Randolph Road, Hanscom
More informationSize, shape, orientation, speed, and duration of GPS equatorial anomaly scintillations
RADIO SCIENCE, VOL. 39,, doi:10.1029/2003rs002878, 2004 Size, shape, orientation, speed, and duration of GPS equatorial anomaly scintillations P. M. Kintner and B. M. Ledvina School of Electrical and Computer
More informationSouth Atlantic magnetic anomaly ionization: A review and a new focus on electrodynamic effects in the equatorial ionosphere
Journal of Atmospheric and Solar-Terrestrial Physics 67 (25) 1643 1657 www.elsevier.com/locate/jastp South Atlantic magnetic anomaly ionization: A review and a new focus on electrodynamic effects in the
More informationSatellite Navigation Science and Technology for Africa. 23 March - 9 April, Scintillation Impacts on GPS
2025-29 Satellite Navigation Science and Technology for Africa 23 March - 9 April, 2009 Scintillation Impacts on GPS Groves Keith Air Force Research Lab. Hanscom MA 01731 U.S.A. Scintillation Impacts on
More informationEffects observed in the Latin American sector ionospheric F region during the intense geomagnetic disturbances in the early part of November 2004
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114,, doi:10.1029/2007ja013007, 2009 Effects observed in the Latin American sector ionospheric F region during the intense geomagnetic disturbances in the early part
More informationRegional ionospheric disturbances during magnetic storms. John Foster
Regional ionospheric disturbances during magnetic storms John Foster Regional Ionospheric Disturbances John Foster MIT Haystack Observatory Regional Disturbances Meso-Scale (1000s km) Storm Enhanced Density
More informationGlobal dayside ionospheric uplift and enhancement associated with interplanetary electric fields
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109,, doi:10.1029/2003ja010342, 2004 Global dayside ionospheric uplift and enhancement associated with interplanetary electric fields Bruce Tsurutani, 1 Anthony Mannucci,
More informationRecebido em 23 fevereiro, 2006 / Aceito em 21 maio, 2007 Received on February 23, 2006 / Accepted on May 21, 2007
Revista Brasileira de Geofísica (2007) 25(Supl. 2): 151-158 2007 Sociedade Brasileira de Geofísica ISSN 0102-261X www.scielo.br/rbg STUDY OF IONOSPHERIC IRREGULARITIES DURING INTENSE MAGNETIC STORMS Luiz
More informationNAVIGATION SYSTEMS PANEL (NSP) NSP Working Group meetings. Impact of ionospheric effects on SBAS L1 operations. Montreal, Canada, October, 2006
NAVIGATION SYSTEMS PANEL (NSP) NSP Working Group meetings Agenda Item 2b: Impact of ionospheric effects on SBAS L1 operations Montreal, Canada, October, 26 WORKING PAPER CHARACTERISATION OF IONOSPHERE
More informationGlobal Maps with Contoured Ionosphere Properties Some F-Layer Anomalies Revealed By Marcel H. De Canck, ON5AU. E Layer Critical Frequencies Maps
Global Maps with Contoured Ionosphere Properties Some F-Layer Anomalies Revealed By Marcel H. De Canck, ON5AU In this column, I shall handle some possibilities given by PROPLAB-PRO to have information
More informationVertical E B drift velocity variations and associated low-latitude ionospheric irregularities investigated with the TOPEX and GPS satellite data
Annales Geophysicae (2003) 21: 1017 1030 c European Geosciences Union 2003 Annales Geophysicae Vertical E B drift velocity variations and associated low-latitude ionospheric irregularities investigated
More informationRECOMMENDATION ITU-R P Prediction of sky-wave field strength at frequencies between about 150 and khz
Rec. ITU-R P.1147-2 1 RECOMMENDATION ITU-R P.1147-2 Prediction of sky-wave field strength at frequencies between about 150 and 1 700 khz (Question ITU-R 225/3) (1995-1999-2003) The ITU Radiocommunication
More informationRESEARCH ACTIVITIES AT INPE USING GPS RECEIVERS. Eurico R. de Paula, Ivan J. Kantor and Luiz Felipe C. de Rezende INPE- São José dos Campos São Paulo
RESEARCH ACTIVITIES AT INPE USING GPS RECEIVERS Eurico R. de Paula, Ivan J. Kantor and Luiz Felipe C. de Rezende INPE- São José dos Campos São Paulo OUTLINE -GPS RECEIVERS LOCATION OVER BRAZIL -IONOSPHERIC
More informationPUBLICATIONS. Radio Science. On the mutual relationship of the equatorial electrojet, TEC and scintillation in the Peruvian sector
PUBLICATIONS RESEARCH ARTICLE Special Section: Ionospheric Effects Symposium 2015 Key Points: We examined the relationship between EEJ, TEC, and S 4 index in low-latitude ionosphere We found correlation/dependencies
More informationHF Doppler radar observations of vertical and zonal plasma drifts Signature of a plasma velocity vortex in evening F-region
Indian Journal of Radio & Space Physics Vol. 35, August 2006, pp. 242-248 HF Doppler radar observations of vertical and zonal plasma drifts Signature of a plasma velocity vortex in evening F-region C V
More informationCHAPTER 1 INTRODUCTION
CHAPTER 1 INTRODUCTION The dependence of society to technology increased in recent years as the technology has enhanced. increased. Moreover, in addition to technology, the dependence of society to nature
More informationMEETING OF THE METEOROLOGY PANEL (METP) METEOROLOGICAL INFORMATION AND SERVICE DEVELOPMENT WORKING GROUP (WG-MISD)
METP-WG/MISD/1-IP/09 12/11/15 MEETING OF THE METEOROLOGY PANEL (METP) METEOROLOGICAL INFORMATION AND SERVICE DEVELOPMENT WORKING GROUP (WG-MISD) FIRST MEETING Washington DC, United States, 16 to 19 November
More informationGINESTRA MIMOSA - MEDSTEC COMPETENCE SURVEYS WITHIN THE ESA ALCANTARA INITIATIVES
GINESTRA MIMOSA - MEDSTEC COMPETENCE SURVEYS WITHIN THE ESA ALCANTARA INITIATIVES Lucilla Alfonsi, Gabriella Povero, Julian Rose TENTH EUROPEAN SPACE WEATHER WEEK. Antwerp, 19 th November 2013 WHAT? MImOSA
More informationCorrelation of in situ measurements of plasma irregularities with ground based scintillation observations
Click Here for Full Article JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115,, doi:10.1029/2010ja015288, 2010 Correlation of in situ measurements of plasma irregularities with ground based scintillation observations
More informationDartmouth College SuperDARN Radars
Dartmouth College SuperDARN Radars Under the guidance of Thayer School professor Simon Shepherd, a pair of backscatter radars were constructed in the desert of central Oregon over the Summer and Fall of
More informationChapter 6 Propagation
Chapter 6 Propagation Al Penney VO1NO Objectives To become familiar with: Classification of waves wrt propagation; Factors that affect radio wave propagation; and Propagation characteristics of Amateur
More informationIonospheric Storm Effects in GPS Total Electron Content
Ionospheric Storm Effects in GPS Total Electron Content Evan G. Thomas 1, Joseph B. H. Baker 1, J. Michael Ruohoniemi 1, Anthea J. Coster 2 (1) Space@VT, Virginia Tech, Blacksburg, VA, USA (2) MIT Haystack
More informationELECTROMAGNETIC PROPAGATION (ALT, TEC)
ELECTROMAGNETIC PROPAGATION (ALT, TEC) N. Picot CNES, 18 Av Ed Belin, 31401 Toulouse, France Email : Nicolas.Picot@cnes.fr ABSTRACT For electromagnetic propagation, the ionosphere plays a key role. This
More informationStudy on the occurrence characteristics of VHF and L-band ionospheric scintillations over East Africa
Indian Journal of Radio & Space Physics Vol 43, August - October 2014, pp 263-273 Study on the occurrence characteristics of VHF and L-band ionospheric scintillations over East Africa F M D ujanga $,*
More informationUsing GNSS Tracking Networks to Map Global Ionospheric Irregularities and Scintillation
Using GNSS Tracking Networks to Map Global Ionospheric Irregularities and Scintillation Xiaoqing Pi Anthony J. Mannucci Larry Romans Yaoz Bar-Sever Jet Propulsion Laboratory, California Institute of Technology
More informationUnexpected connections between the stratosphere and ionosphere
Click Here for Full Article GEOPHYSICAL RESEARCH LETTERS, VOL. 37,, doi:10.1029/2010gl043125, 2010 Unexpected connections between the stratosphere and ionosphere L. P. Goncharenko, 1 J. L. Chau, 2 H. L.
More informationA statistical study of large-scale traveling ionospheric disturbances observed by GPS TEC during major magnetic storms over the years
Click Here for Full Article JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113,, doi:10.1029/2008ja013037, 2008 A statistical study of large-scale traveling ionospheric disturbances observed by GPS TEC during major
More information3-2-2 Effects of Transequatorial Thermospheric Wind on Plasma Bubble Occurrences
3-2-2 Effects of Transequatorial Thermospheric Wind on Plasma Bubble Occurrences Data from the ionosonde chain in Southeast Asia (Kototabang, Indonesia (0.2 S, 100.3 E), Chumphon, Thailand (10.7 N, 99.4
More informationIntroduction to HF Propagation. Rick Fletcher, W7YP FVARC November 20, 2018
Introduction to HF Propagation Rick Fletcher, W7YP FVARC November 20, 2018 Topics The HF Bands How HF propagation works Overview by HF band Sources of solar and propagation information Working HF during
More informationStorms in Earth s ionosphere
Storms in Earth s ionosphere Archana Bhattacharyya Indian Institute of Geomagnetism IISF 2017, WSE Conclave; Anna University, Chennai Earth s Ionosphere Ionosphere is the region of the atmosphere in which
More informationSpace weather impact on the equatorial and low latitude F-region ionosphere over India
Space weather impact on the equatorial and low latitude F-region ionosphere over India R. S. Dabas, R. M. Das, V. K. Vohra, C. V. Devasia To cite this version: R. S. Dabas, R. M. Das, V. K. Vohra, C. V.
More informationAssimilation Ionosphere Model
Assimilation Ionosphere Model Robert W. Schunk Space Environment Corporation 221 North Spring Creek Parkway, Suite A Providence, UT 84332 phone: (435) 752-6567 fax: (435) 752-6687 email: schunk@spacenv.com
More informationISR Coordinated Science at Equatorial Latitudes
ISR Coordinated Science at Equatorial Latitudes J. L. Chau 1, D. L. Hysell 2, and E. Kudeki 3 1 Radio Observatorio de Jicamarca, Instituto Geofísico del Perú, Lima 2 Earth and Atmospheric Sciences, Cornell
More informationPenetration characteristics of the interplanetary electric. field to the day-time equatorial ionosphere.
1 2 Penetration characteristics of the interplanetary electric field to the day-time equatorial ionosphere. 3 4 5 C. Manoj, 6 7 8 9 CIRES, University of Colorado, Boulder, USA NGDC/NOAA 325 Broadway, Boulder,
More information4 Ionosphere and Thermosphere
4 Ionosphere and Thermosphere 4-1 Ionospheric Irregularities Ionospheric irregularities cause scintillations of trans-ionospheric radio waves from satellites. Most severe cases are the scintillations due
More informationStudy of amplitude and phase scintillation at GPS frequency
Indian Journal of Radio & Space Physics Vol. 34, December 25, pp. 42-47 Study of amplitude and phase scintillation at GPS frequency Smita Dubei, Rashmi Wahi 1, Ekkaphon Mingkhwan 2 & A K Gwal 1 1 Space
More informationResponse of the equatorial and low-latitude ionosphere during the space weather events of April 2002
Annales Geophysicae (4) 22: 3211 3219 SRef-ID: 1432-576/ag/4-22-3211 European Geosciences Union 4 Annales Geophysicae Response of the equatorial and low-latitude ionosphere during the space weather events
More informationThe Atmosphere and its Effect on GNSS Systems 14 to 16 April 2008 Santiago, Chile
Description of a Real-Time Algorithm for Detecting Ionospheric Depletions for SBAS and the Statistics of Depletions in South America During the Peak of the Current Solar Cycle The Atmosphere and its Effect
More informationSuppression of equatorial spread F by sporadic E
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 107, NO. A2, 1021, 10.1029/2001JA000162, 2002 Suppression of equatorial spread F by sporadic E Andrew W. Stephan, 1,2 Marlene Colerico, 3 Michael Mendillo, 3 Bodo
More informationPropagation During Solar Cycle 24. Frank Donovan W3LPL
Propagation During Solar Cycle 24 Frank Donovan W3LPL Introduction This presentation focuses on: The four major fall and winter DX contests: CQ WW SSB and CW ARRL DX SSB and CW The years of highest solar
More informationStatistical modeling of ionospheric fof2 over Wuhan
RADIO SCIENCE, VOL. 39,, doi:10.1029/2003rs003005, 2004 Statistical modeling of ionospheric fof2 over Wuhan Libo Liu, Weixing Wan, and Baiqi Ning Institute of Geology and Geophysics, Chinese Academy of
More informationTime of flight and direction of arrival of HF radio signals received over a path along the midlatitude trough: Theoretical considerations
RADIO SCIENCE, VOL. 39,, doi:10.1029/2004rs003052, 2004 Time of flight and direction of arrival of HF radio signals received over a path along the midlatitude trough: Theoretical considerations D. R. Siddle,
More informationNON-TYPICAL SERIES OF QUASI-PERIODIC VLF EMISSIONS
NON-TYPICAL SERIES OF QUASI-PERIODIC VLF EMISSIONS J. Manninen 1, N. Kleimenova 2, O. Kozyreva 2 1 Sodankylä Geophysical Observatory, Finland, e-mail: jyrki.manninen@sgo.fi; 2 Institute of Physics of the
More informationDaytime modelling of VLF radio waves over land and sea, comparison with data from DEMETER Satellite
Daytime modelling of VLF radio waves over land and sea, comparison with data from DEMETER Satellite S. G. Meyer 1,2, A. B. Collier 1,2, C. J. Rodger 3 1 SANSA Space Science, Hermanus, South Africa 2 School
More informationPositive and negative GPS-TEC ionospheric storm effects during the extreme space weather event of March 2015 over the Brazilian sector
Utah State University DigitalCommons@USU All Physics Faculty Publications Physics 6-1-2016 Positive and negative GPS-TEC ionospheric storm effects during the extreme space weather event of March 2015 over
More informationRadio tomography based on satellite beacon experiment and FORMOSAT- 3/COSMIC radio occultation
Radio tomography based on satellite beacon experiment and FORMOSAT- 3/COSMIC radio occultation Mamoru Yamamoto (1), Smitha V. Thampi (2), Charles Lin (3) (1) RISH, Kyoto University, Japan (2) Space Physics
More informationReport of Regional Warning Centre INDIA, Annual Report
Report of Regional Warning Centre INDIA, 2013-2014 Annual Report A.K Upadhayaya Radio and Atmospheric Sciences Division, National Physical Laboratory, New Delhi-110012, India Email: upadhayayaak@nplindia.org
More informationAn error analysis on nature and radar system noises in deriving the phase and group velocities of vertical propagation waves
Earth Planets Space, 65, 911 916, 2013 An error analysis on nature and radar system noises in deriving the phase and group velocities of vertical propagation waves C. C. Hsiao 1,J.Y.Liu 1,2,3, and Y. H.
More informationanalysis of GPS total electron content Empirical orthogonal function (EOF) storm response 2016 NEROC Symposium M. Ruohoniemi (3)
Empirical orthogonal function (EOF) analysis of GPS total electron content storm response E. G. Thomas (1), A. J. Coster (2), S.-R. Zhang (2), R. M. McGranaghan (1), S. G. Shepherd (1), J. B. H. Baker
More informationNighttime sporadic E measurements on an oblique path along the midlatitude trough
RADIO SCIENCE, VOL. 46,, doi:10.1029/2010rs004507, 2011 Nighttime sporadic E measurements on an oblique path along the midlatitude trough A. J. Stocker 1 and E. M. Warrington 1 Received 25 August 2010;
More informationPlasma effects on transionospheric propagation of radio waves II
Plasma effects on transionospheric propagation of radio waves II R. Leitinger General remarks Reminder on (transionospheric) wave propagation Reminder of propagation effects GPS as a data source Some electron
More information