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Please give an example of a scientific hypothesis about Antarctica that has not yet been confirmed. I am also interested in the gaps in scientific knowledge about Antarctica. As a member of Russian Antarctic program I am familiar with general enigmas (ice sheet stability, life in subglacial lakes, paleoclimatic records, influence of subglacial heat flows etc.). So here I would like you to share with me not so common things about Antarctica
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The role of volcanic activity as a significant factor contributing to ice melt still awaits a confirmation. For some further details please kindly consult the following site:
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Models of the Earth's atmosphere receive a lot of attention in today's warming climate, but models of the Earth's ionosphere are just as important. Which model incorporates more accurate methods of measuring solar activity? Attempts by numerous researchers to assess the performance of models such as IRI and NeQuick test release have yielded results that differ by regions so far. To date, which method has proven to be more accurate in predicting ionospheric parameters, particularly TEC?
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Empirical models (e.g., Klobuchar, IRI, NeQuick) are simple and suitable for routine applications Global Navigation Satellite System (GNSS) positioning, and physics-based models (e.g., TIEGCM, SAMI) are more complex but can help to better understand the physical mechanisms. Models are routinely being updated, with better proxies and equations, and the latest models are usually the more accurate.
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I want to compare two TEC models. Except the comparison of diurnal vTEC, I want to analyze deviation in mean monthly vTEC by taking single airthematic average for whole month. While doing so, I am averaging quiet day as well as disturbed day TEC. But my study is not adressing the performance of models in disturbed or quiet day. Study is focused on overall performance. So, what I believe is if two models are predicting TEC of same location then both should give the similar average for the month. But I want to confirm, wheather other statistical factor effects the value while mixing quiet day and disturbed day TEC or not?? Is this concept significant in comparing two TEC models?
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In my opinion, it's better to distinguish the study into disturbed and quiet period to validate the performance of the model. This is because, the average value of the entire month sometime fails to address the storm effect on the vTEC. By dividing the study into two separate categories, we will have better overview of their overall performance.
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I am working with a Septrino PolaRxs GPS receiver which receives the data from GPS satellites and after some initial processing stores it in .ismr format (ISMR= Ionospheric Scintillation Monitoring Records).
Though I am able to open the data file in a notepad I don't exactly know how to read the data. Is there any program or algorithm available in matlab which can help me in reading the ismr files?
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You can Use 'csvread' command in MATLAB to read the data.
Syntax - Data = csvread('filename.ismr');
Later, you can select any column based on your requirements.
Hope this helps you.
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I have a set of scatter plots comparing some different data with a reference value. I'm evaluating the quality of these comparisons by analysing slope, intercept and r values. Thus, too many similar figures can make it difficult to understand.
How can I improve this?
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There are three ways, I'd consider:
Group the figures into figura 1a, 1b,1c... so you don't need the write the caption multiple times.
If colors are allowed you could try to put all plots in one graph and use multiple y-axes whose colors correspond to the colors of your scatter-plots (depends on how many figures you actually have.... Probably too messy with more than four figures).
If the figures itself are not so important, and you only need the regression results in your analysis, I would include the drawing in a supplementary file for the reviewers and/or as supplementary data for the online version of the manuscript.
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I have been developing models of the ionosphere for some time, but recently, I've been asked "What constitutes sufficiently accurate foF2?" The URSI standard for foF2 scaling from an ionogram is 5d, where d is the frequency resolution of the ionosonde in the vicinity of foF2. Others have mentioned accuracy standards ranging between 0.5 MHz and 1.0MHz. My question is, is there a consensus within the field on the generally required accuracy of foF2? If it is application-specific, what are the necessary accuracy levels for these various applications?
In any responses, please provide references to support your point of view.
I look forward to an interesting and productive discussion.
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Dear David, imho maybe accuracy in terms of "MHz" is not sufficient, since there's a significant daily and seasonal foF2 variation (i.e. any MHz specification will be much less sufficient let's say for night- than daytime). I will try to check any valid accuracy standard and turn back to you.
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Hello every one,
I am interested to download the 3-hourly ap indices for one day. As it gives single value for each 3-hour interval of the universal time day (UT), so there will be 8 indices in one day. Th e procedure used to select parameters is shown in the attahched figures. The problem here is, i got 9 indices instead of 8. Any help will be appreciated.
Thanks
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The IRI reads their indices from reference files here: http://irimodel.org/indices/apf107.dat
The file is organized as follows: year, month, day, 8 ap values, daily mean ap, etc...
As for the issue you mention above (regarding the repeating indices), the IRI uses the ap at an hour to define the ap for the next three hours (e.g. the ap at 00UT is used for everything between 0UT and 2:59UT). The 24UT value is the same as the 21UT value because the IRI treats individual days separately. In this way, it has no way of knowing what the ap is at 00UT the next day, so it treats the 24UT value as an extension of the 21UT 3-hour block.
Also, if you are just looking for Kp and ap, you can get Kp and ap values directly from the following ftp: ftp://ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP
The format of that file is given in the kp_ap.fmt file.
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Scientist got different results if the radiation from cell phones have an influence on bees or not - may be the situation in the laboratory is not quite the same in the nature and for example if there is a problem with a geomagnetic storm there is suddendly more influence from the radiation from cell phones as on the most other days and this could explain the different results and opinions???
May be the bees react on geomagnetic storms too without radiation from cell phones? But now this influence is stronger?
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A geomagnetic storm (or any additional imposed field) will not directly affect an EM wave and will certainly not shift frequency, etc.  What CAN have an effect are the associated atmospheric changes, e.g. charged particles in the atmosphere, which can change the propagation properties through the charged dielectric.  For example, ionospheric charging changes between day and night altering the ionospheric bounce and penetration of the upper atmosphere.  That said, terrestrial communication like cell phones will see negligible impact from any such effects.  A rain storm (water in the atmosphere) has a much more significant impact on that communication propagation.  On the other hand, satellite communication and long range over-the-horizon terrestrial communication that relies on ionospheric bounce (e.g. HAM radio) can be significantly impacted by upper atmospheric effects.  
Beyond that, the effects of external fields do not alter the fields from the radio communication.  They simply sum with those signals at the receiver, so you may have interference due to the additional noise power from the storm (e.g. when a lightning strike causes static on your radio), but the signal power remains the same.
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I need to obtain real heights of reflection of radio waves from ionograms for the purpose of finding some numerical solutions to electron density continuity equation in the F2 region at a low latitude station.
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Hello Efiong,
Please refer to the user manuals or some reference documentation related to the POLAN software. The article linked below is authored by J.E. Titheridge.
I hope it will be useful for your data analysis.
Thanks with best wishes!
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1. Why and how does one check the stationarity of a time series?
2. How does one calculate the PSD of a time series as one in the attachment (Book1.txt)?
3. What is meant by the term "confidence limit" in context of calculating PSD?
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Hello Bidyut,
Stationarity just means that the statistical properties of a time-series don't change over time.  If you want to check for any trends in your data, then test it for stationarity.  Probably the simplest way to check for stationarity is to split your total timeseries into 2, 4, or 10 (say N) sections (the more the better), and compute the mean and variance within each section.  If there is an obvious trend in either the mean or variance over the N sections, then your series is not stationary.  If not, then is may well be stationary.
I took your data file (Book1.txt), and computed the mean and std. deviation within each consecutive set of 600 points; results are in the file attached.  The mean certainly does look stationary, and variability of the 600-point mean is much less than the std. deviation within each 600-point section, which is good evidence for the stationarity of the overall series.  The std. deviation within each section does jump around a bit, but at least doesn't show any clear trend. 
For calculations of the PSD (power spectral density), see, e.g., this page:  www.ldeo.columbia.edu/users/menke/edawm/eda_lectures/lec12.pptx .  You will need to run a Fourier transform on your data.  The PSD is a function of frequency; the dominant periodicities in your time-series show up as peaks in the PSD curve (plotted as function of frequency).
As for "confidence" in your PSD calculations, again, split the total series into sections, compute the PSDs for each; if they are all very similar, you should have high confidence that they are "representative"; if not, then you should have low confidence in any one of them.  You can use Chi^2 statistics to quantify these "confidence" levels more formally.  See https://www.vibrationresearch.com/public_pdf/StatisticalPropertiesOfRandomPSD.pdf for a good explanation of the theory behind this.
Also, See https://cran.r-project.org/web/packages/psd/vignettes/psd_overview.pdf for info. on how to do all these calculations in R. 
I hope the above helps a bit!
-Enda
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Hello, I am looking for a figure (with reference) that is similar to the one attached (replyfig.png), which compares the day and night side ionospheric electron density profiles typical of mid-latitude. I know the high latitude ionosphere is highly variable (Ne_at_high_*.jpg), but was wondering if perhaps there was something similar from long term averages of day and night data for an instrument located somewhere between 60-80 degrees North latitude. I may look at some EISCAT data otherwise.
Cheers
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Below are some figures you can generate using the RISR-N system in Resolute. Unfortunately, the SNR is pretty low with that ISR, particularly during winter and low solar activity periods. If you were to look at individual profiles, I don't believe you'll be able to distinguish the types of features you want to identify on a figure, such as what you're describing, using this system (See the 30-minute averaged profile examples for January 2011 and June 2013 attached below). Also, you won't get above 1000km with any of the high latitude ISRs. Even Arecibo has a hard time getting that high up.
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I am a freelance researcher interested in Ionospheric studies.I am looking for people who are working in the Earth Energy Budget. I will be happy to interact with anybody who can help me in this subject.
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Happy to hear that the subject appeals to freelancers also. If possible please visit Andhra University, Dept. Of Physics. They have a very strong group in the field of Ionosphere.
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I would like to find data for Total Electron Content (TEC) as a function of latitude (TEC curves possibly from GPS observations). I also will need an ionospheric map (electron density as a function of altitude and latitude), possibly reconstructed from the TEC data or measured using another source such as radar. I wish to validate my raytrace program by passing rays through the ionospheric map, attempting to reproduce the previously measured TEC curve(s). Any suggestions for open-access databases or journal articles with both TEC curves and electron density maps would be greatly appreciated!
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Code will give you interpolated (spherical harmonic fitted) TEC maps on a 2.5x5.0 lat x lon grid in two-hour temproal resolution. Rather than just using the CODE maps, however, you can also look at the IONEX TEC maps generated by each of the global analysis centers (IGS, CODE, JPL, ESA, etc...). The CODE, IGS, and JPL maps are generally considered the more reliable. ftp://cddis.gsfc.nasa.gov/gnss/products/ionex/
Instructions on how to navigate their ftp and about the data format can be found here: http://cddis.gsfc.nasa.gov/Data_and_Derived_Products/GNSS/atmospheric_products.html#iono
You can also try Anthea Coster's Madrigal TEC maps, which don't use any interpolation (leaving you to choose how you want to interpolate the data). You can get that data here: http://madrigal.naic.edu/ No account is needed but they do ask for your email an institution information for their records.
Electron density is another beast all together. There doesn't really exist a reliable electron density model out there. The IRI has it's issues at high and low latitudes and the TIEGCM (http://www.hao.ucar.edu/modeling/tgcm/) isn't really at the stage where it can be considered for operational use. There are assimilation models out there, but none of them are openly available or run regularly.
For a formal evaluation, you may want to consider case-studies and seeing if you can get any of your data near one of the North American Incoherent Scatter Radars, which can get accurate, high-resolution electron density information. Poker Flat or Millstone Hill would probably be ideal. Poker Flat is a phased array scanning many beam directions at once and has a bunch of GPS receivers in its vicinity. Millstone Hill is in the central mid-latitudes with excellent range and is covered by an even larger array of GPS receivers. The ISR data can be retrieved from the same Madrigal site I posted a link to above. (They're also hosting an ISR Summer School in Europe this summer that you may be interested in attending -room, board, and flights are generally covered-). http://amisr.com/workshop
Alternatively, I'll be publishing my empirical electron density model for 60+ Magnetic Latitudes later this month. I'll send you the model as soon as I've finished optimizing it, if you want. Until then you can try the IRI and just see what kind of results you get. You can also scale IRI NmF2 to match map TEC, which may work OK at mid latitudes (big issues at high latitudes though).  
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Hey guys,
I am trying to estimate mainly the pressure but also the temperature that occurs in the plasma of an artificial current that mimics a lightning strike.
Looking forward to your answer and until then let's keep making the world a happier place!
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See, "The Density, Pressure, and Particle Distribution in a Lightning
Stroke near Peak Temperature" by Martin A. Uman, Richard E Orville, and Leon E Salanave in the Journal of Atmospheric Sciences, Volume 21, May, 1964, pp 306-311.
Uman, et al, estimate the average temperature  to be 24000K and a peak pressure of 18 atmospheres. 
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I have a PhD student who is currently analyzing Demeter satellite data in order to assess their usefulness in earthquake and other natural disaster precursory studies. We are having problems accessing TEC data in the earthquake stricken areas. Please, we need to know if there is any TEC data depository or data bank from where we can download such data. Thanks
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How about the GEONET TEC database from Japan?   http://stegps.kugi.kyoto-u.ac.jp/
The IONEX data is also available at http://aiuws.unibe.ch/ionosphere/
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I am carrying out an investigation on plasma drift during the evening time, I observed that the average PRE magnitude for a complete solar cycle during the June solstice (covering May to July) peaked an hour after all other seasons had peaked. What could be responsible?
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The PRE is related to the ionosphric dynamo which is related to neutral wind. The neutral wind have seasonal variations, so it it is normal the PRE depends also of the season
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Seasonal investigations of vertical plasma drift had always shown June solstice recording the smallest magnitude.
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I suggest you read the paper by Sharma and Muldrew, Seasonal and longitudinal variations in the occurrence frequency of magnetospheric ionization ducts, which can be found in ReserchGate. The asymmetry in the angle between the geomagnetic pole and the the sun-earth line at night affects the occurrence frequency of ducts and spread F and I suspect it would also affect plasma drifts. If possible you could verify this by observing a longitudinal affect.
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Ionospheric horizontal gradient does effect the GPS positioning over the equatorial region. It will be great if there is a method to model the ionosphere. Great if anyone can share. Thanks
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Karthigesu,
Are you trying to develop a physics-based model for the ionosphere gradients, or are you seeking a representation from observational data?
The SUPIM reference (Bailey and Balan, 1996) in "TEC Measurements..." contains information about the physical processes, while the IONEX reference (Schaer, Gurtner, and Feltens, 1998) describes a representation of GPS data.  There are examples of both SUPIM and IONEX results in "TEC Measurements ...".
Andrew Mazzella
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How the asymmetric ring current affects the Dst index.
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The main cause of the asymmetric ring current is the very nature of the ion transport around our planet. Ions drift duskward and part of the ion distribution is lost through the magnetopause - especially during intense storms, when the magnetopause is usually pushed earthward by the higher-than-usual solar wind pressure (mostly due to an ICME). Consequently not all ions complete their full drifts around the planet and the result is an asymmetric ring current with maximum intensity in the duskside magnetosphere.
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I want details on E-layer and sporadic E-layer which are present in ionosphere.
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In addition to the previous answers I would like to add that ionosphere by itself was discovered due to the E-layer and exactly due to its influence on radio wave propagation.
After the first experiment of Marconi with transeatlantic radio-signal transmission from the Europe to the North America (1901), the conclusion about the existing of reflecting layer in the sky was done independently by Kennelly (1902) and Heaviside (1902). They primarily estimated this reflection layer height as about 80 km. Direct registration of Kennelly – Heaviside layer (using the radio reflections analysis) was done by Appleton (1925). It was appeared that this layer is localized a little bit higher than it was expected before. Appleton called this reflecting layer as “E-layer” (from “Electric”). When another ionosphere layers (above and below of E-layer) were discovered then, they were called respectively in alphabet order – D, E, F.
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High energy astrophysicsts  and Nuclear Physicists
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Rather than answering your question in frequency, it would be more realistic to answer in energy, simply the frequency is so high that gamma ray behave more like a particle (photon) than a wave. The CGRO and other satellite experiment can detect gamma ray only up to several 100s GeV or < 1TeV = 1.E12 eV. Higher than that, the flux is so low that satellite instruments loss detection power or their discrimination power to separate gamma from much higher flux of cosmic rays. The Ground gamma ray telescope can detect gamma photons interaction with atmosphere via indirect measurement. The highest energy of gamma ray  of those experiments can reach approximately 1.E14 eV, in terms of frequency ~ 2.4E28 Hertz.
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And if possible the methodology of extracting such datasets.
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Thank you for the address. I have started working it out.
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In order to find a cause–consequence relation between the preparing earthquake and the preceding ionospheric disturbances, a series of hypothetical mechanisms was proposed (Pulinets and Boyarchuk, 2004).
The best known among them are mechanisms related to the penetration into the ionosphere of a seismogenic electric field and/or acoustic gravity waves (AGWs), which are excited in the nearsurface atmosphere over the earthquake preparation zone.
According to the formed mechanism, it is assumed that in the process of earthquake preparation, a quasistatic electric field could be generated which is capable of penetrating to ionospheric levels and leading to disturbances in the ionospheric plasma density. In particular, as calculations show, sporadic layers could be formed in the ionospheric Е region (Kim et al., 1993;Sorokin et al., 2006), whereas at heights of the F region the seismogenic electric field could lead to substantial changes in the distribution of the plasma concentration in the ionospheric F region due to an electromagnetic drift of plasma excited by it (Kim and Hegai, 1999; Namgaladze et al., 2009; Liu et al., 2011;Klimenko et al., 2011a).
According to the latter mechanism, AGWs, which are excited in the near surface atmosphere during earthquake preparation and then arrive to the ionosphere (Pertsev and Shalimov, 1996; Mareev et al.,2002; Molchanov, 2004) or are generated in the ionosphere itself due to the Joule heating caused by the seismogenic electric field (Hegai et al., 1997), could serve as a source of ionosphereic disturbances prior to earthquakes.
Such AGWs can lead to the formation of plasma irregularities both in the Е (Blaunstein and Hayakawa, 2009) and F (Hegai et al., 2006) regions. Model simulations (Klimenko et al., 2011b) show that seismogenic AGWs can cause changes in the neutral atmosphere composition in the ionospheric F region, to which, in their turn, disturbances in the electron concentration are related.
REFERENCES
Blaunstein, N. and Hayakawa, M., Short_term ionospheric precursors of earthquakes using vertical and oblique ionosondes, Phys. Chem. Earth. A–C, 2009, vol. 34, nos. 6–7, pp. 496–507.
Hegai, V.V., Kim, V.P., and Nikiforova, L.I., A possible generation mechanism of acoustic-gravity waves in the ionosphere before strong earthquake, J. Earthquake Predict. Res., 1997, no. 6, pp. 584–589.
Hegai, V.V., Kim, V.P., and Liu, J.Y., The ionospheric effect of atmospheric gravity waves excited prior to strong earthquake, Adv. Space Res., 2006, vol. 37, no. 4, pp. 653–659.
Kim, V.P., Khegai, V.V., and Illich_Svitych, P.V., On the possible formation of the layer of metal ions in the nighttime midlatitude ionospheric E region before strong earthquakes, Geomagn. Aeron., 1993, vol. 33, no. 5, pp. 114–119.
Kim, V.P. and Hegai, V.V., A possible presage of strong earthquakes in the night_time mid_latitude F2 region ionosphere, in Atmospheric and Ionospheric Electromagnetic Phenomena Associated with Earthquakes, Hayakawa, M., Ed., Tokyo: Terra Sci. Publ., 1999, pp. 619–627.
Klimenko, M.V., Klimenko, V.V., Zakharenkova, I.E., Pulinets, S.A., Zhao, B., and Tsidilina, M.N. Formation mechanism of great positive TEC disturbances prior to Wenchuan earthquake on may 12, 2008, Adv. Space Res., 2011a, vol. 48, no. 3, pp. 488–499.
Klimenko, M.V., Klimenko, V.V., Karpov, I.V., and Zakharenkova, I.E., Modeling of seismoionospheric effects initiated by internal gravity waves, Russ. J. Phys. Chem., 2011b, vol. 30, no. 5, pp. 41–49.
Liu, J.Y., Le, H., Chen, Y.I., et al., Observations and simulations of seismoionospheric GPS total electron content anomalies before the 12 January 2010 M7 Haiti earthquake, J. Geophys. Res., 2011, vol. 116, p. A04302.
Mareev, E.A., Iudin, D.I., and Molchanov, O.A., Mosaic source of internal gravity waves associated with seismic activity, in Seismo_Electromagnetics (Lithosphere–Atmosphere–Ionosphere Coupling), Hayakawa, M. and Molchanov, O.A., Eds., Tokyo: Terra Sci. Publ., 2002, pp. 335–342.
Molchanov, O.A., On the origin of low- and middle-latitude ionospheric turbulence, Phys. Chem. Earth. A–C, 2004, vol. 29, no. 4–9, pp. 559–567.
Namgaladze, A.A., Klimenko, M.V., Klimenko, V.V., and Zakharenkova, I.E., Physical mechanism and mathematical modeling of earthquake ionospheric precursors registered in total electron content, Geomagn. Aeron., 2009, vol. 49, pp. 252–262.
Pertsev, H.H. and Shalimov, S.L., The generation of atmospheric gravity waves in a seismically active region and their effect on the ionosphere, Geomagn. Aeron., 1996, vol. 36, pp. 223–227.
Pulinets, S.A. and Boyarchuk, K.A., Ionospheric precursors of earthquakes, Berlin: Springer, 2004.
Sorokin, V.M., Yaschenko, A.K., and Hayakawa, M., Formation mechanism of the lower ionospheric disturbances by the atmospheric electric current over a seismic region, J. Atmos. Solar–Terr. Phys., 2006, vol. 68,no. 11, pp. 1260–1268.
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We let assume that sunspot number (SSN) ranges from 0 to 200. In this case, when SSN was greater than 50, it is solar maximum, otherwise it is solar minimum. Is this correct?
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No, this is not correct. SSN has a cycle with an average period of 11 years from minimum to maximum and back to minimum. Different SSN cycles have different amplitudes, modulated by a century-scale variability (the so called Gleissberg cycle). Plus, there are prolonged periods of grand minima and maxima of solar activity. In some low amplitude cycles SSN may never reach 50, in some high amplitude cycles 50 is not yet maximum. To determine sunspot minimum and maximum, you must look at the whole SSN record and identify the years of minimum and maximum SSN. Or, you can just look at published dates, for example http://solarphysics.livingreviews.org/open?pubNo=lrsp-2010-1&amp;page=articlesu13.html.
If you are interested in comparing whatever parameters during solar maximum and minimum conditions, my advice from personal experience is to use the years of maxima and minima +/- 1 year - that is, 3-year periods around SSN extrema.
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Ground-based vertical plasma drift is inferred from the time rate of change of hmF2 or h'F (the virtual height of the F-layer)
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paper about chemical corrections for the vertical plasma drift calculation is for example:
Bitencourt, J. A., Abdu, M. A., A theoretical comparison between apparent and real vertical ionization drift velocities in the equatorial F-region. Journal of Geophysical Research 86: 2451-2454, 1981.
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Is there any method to increase, artificially, the cut-off frequency of ionosphere? Or is it only a solar flare phenomenon.
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The critical frequency of the ionosphere is not a fixed value. It roughly varies with time of day, day of the year, and the 11-year long solar cycle. Short term variation is influence by many factors, of which the solar radiation and the earth magnetic field are the main drivers.
Solar flares may disturb the more usual arrangement of the ionosphere, and can be seen as anomalies in ionospheric radio wave propagation, sometimes even totally disrupting all ionospheric propagation.
The critical frequency of the F-layer is measured near real-time by ionosonde stations. Please take a look at them, they are very informative. The following link is from an ionosonde in Belgium, but there are several in your area as well:
Is your interest driven by radio wave propagation issues, or earth science interest?
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Having understood that various research has been done on equatorial eletrojet (EEJ), the daily, monthly and seasonal dependent has been studied intensively.
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The work dépends of the location of the stations.
If there is one station at latitude 6-9° of the dip equator, you can compute the electric field., see the work Anderson et al. (2004) and Anderson et al. (2006).
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The equatorial/low latitude region pre-reversal enhancement (occurring at close to 1800-2000 h LT) is peerless of the features for the nighttime resurgence of the equatorial ionization anomaly, and the daytime buildup (around 0900-1000 h LT) resulted in the decrease of plasma that occurs later. The kind of changes in the nighttime and daytime I'm referring to is when the PRE and EIA build-up during the daytime peak earlier than speculated period.
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What is responsible for the changes in the daytime and nightime phenomenon of the EXB drift?
To answer this question it is first necessary to characterize/explain the kind of changes observed in the daytime and night time EXB drifts.
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Having in mind that the f2-layer peak height in some instances during quiet and low solar activity conditions can be less than 300 km.
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When the hF > 300 there is no need to make chemical correction.
The reason why h'F and hmF2 are more often often used for obtaining vertical drift is simply because they are standard parameters more easily accessible in the ionosonde data bank. It is more appropriate to use an intermediate height, preferably the true height. Any virtual height should also be okay since the time rate of change may not be very different between the true and virtual heights. I am sending you some reprints in your e-mail address.
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Such as ION model or observation data?
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Depends on what you are looking for. If you are looking for bottomside sounder data, then WDC A has a large number of compiled ionosonde data. For the topside you will have to go to satellite archives such as ROCSAT, COSMIC etc. If you are interested in simulated electron density data, the IRI model is a good option.
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There is not much help available online. I have attached the graph, any help would be appreciated.
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Yes that seems probable. Thank you!