This contribution deals with changes in Earthes ionosphere during most extreme events of Solar activity (Dst > 200nT).

During October - November 2003, in descending phase 11 -year Solar sunspot cycle , two periods of suddenly enhanced solar activity was observed . Two geomagnetic storms (28.10. – 5.11.2003 and 19.11.–23.11.2003) with Kp=9 was accompanied by strong disturbances in Earth ‘s ionosphere .The effects of these strong ionospheric storms as was observed at Pr uhonice observatory (49.59 N; 14.33 E) and other Europian ionospheric stations are described at this paper.

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We analyse Field-Aligned Current (FAC) measurements on board the CHAMP satellite, conducted on days 30.06-02.07.2008. In general, there are 91 crossings over polar regions (46 in the Northern hemisphere and 45 – in the Southern hemisphere). The data are gathered under quiet geomagnetic conditions (Kp<1, Vsw<450km/s, and IMF B_z is within ±3.5nT). On these days most of the FAC measurements fall in the noon (MLT=10-14, Mlat=55-85) and midnight (MLT=16-12, Mlat=55-85) sectors.

FAC sheets of reverse sign and with increasing amplitude. Determination of FAC by single satellite measurement however is accompanied with the following uncertainties:

1. underestimation of the FAC density and
2. appearance of false FAC structures.

Consecutively we apply several procedures to reduce the occurrence of such errors. First, FAC structures of density less than 0.1 mkA/m² were neglected; secondly, all FAC obtained at attack angles (the angle between the satellite trajectory and polar oval) considerably different from 90 degrees (e.g. for angle less than 65 degrees) were discarded. Despite these methodological constraints, the existence of multiple FAC close to the noon-midnight meridian under quiet geomagnetic conditions remains. The multiple FAC structure is more frequent in the night sector, with as much as 7 sheets of alternate sign for IMF B_z>0. This issue is verified for both Northern (summer) and Southern (winter) hemispheres.

The number of all FAC sheets observed in the Southern hemisphere, however, is less than in the Northern one. Our analysis reveals a multitude of alternating medium-scale (at least 1-2 degrees) FAC sheets of reverse sign and with increasing amplitude. There are no regions where the sign of current remains unchanged, therefore, it is not possible to discriminate regions similar to R1/R2. We were unable to find a relationship between Solar Wind (SW)-parameters and observed FAC structures.

We discuss the possible errors arising from single satellite magnetic field measurement.

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Solar wind streams, depending on the periods of solar activity, have different nature. There may be quasi-stationary streams (recurrent streams from coronal magnetic holes) and nonstationary streams (flare streams connected with coronal mass ejections (CME)). In this work the following nonsationary solar wind structures were considered: magnetic clouds (MC), Sheath and CIR regions (regions of interaction of Magnetic clouds and Recurrent Streams with undisturbed solar wind). This study is devoted to the investigation of the influence of nonstastionary solar wind structures on the auroral bulge development. Solar wind parameters were taken from the Wind spacecraft observations and the auroral bulge parameters were obtained by the Ultra Violet Imager onboard Polar. It was shown that auroral bulges "geometry" is different for these types of solar wind structures. The auroral bulges of substorms during magnetic clouds are, in average, wider in longitude and narrower in latitude. As consequence, the ratio between longitudinal and latitudinal sizes for substorms during MC is also larger. Auroral bulges are most extended in both latitude and longitude for CIR- and Sheath- situations. Perhaps, this is due to the influence of the compressed, highly dense solar wind plasma.

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The behaviour of the auroral emissions 5577Å and 6300Å and the ratio I₆₃₀₀/I₅₅₇₇ during substorms has been examined.  For the study, data from the photometer at Cap Heer Observatory (Barenzburg, Spitsbergen), the All-Sky Imagers at Andøya Rocket Range (ARR) (Andenes, Norway ) and at the Auroral Observatory (Longyearbyen, Svalbard) have been used. The substorm onset time and the further development were verified by ground-based data of the IMAGE magnetometers network and by data of the all-sky cameras at Spitsbergen and Andenes. We considered the behaviour of the intensities I₆₃₀₀ and I₅₅₇₇ of the auroral emissions during substorms. It was shown that the precipitation of most energetic electrons occurs at the polar edge of the auroral bulge, and inside the bulge precipitation of less energetic electrons is observed.

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The present study concerns variability of the wave activity in the sporadic E layer plasma. Within oscillations in height (hEs) and critical frequency (foEs) of sporadic E layer together with the temperature in the lower laying neutral atmosphere we search for the wave-like oscillations over a wide period range of hours to several days, covering tidal and planetary oscillation domain. In order to detect modulation of the E layerplasma wave-like oscillation by planetary waves from lower laying atmosphere we analyseoscillation in the neutral atmosphere temperature at the level of 10hPa.

Special campaigns were performed during summer time when the sporadic E layer occurence is highest (data were collected since 2004 till 2008). Critical frequencies foEsand layer heights hEswere analysedby mean of Wavelet Transform. Variability in height and critical frequency of sporadic E layer shows significant periodicities over a wide period range of hours to several days, covering tidal and planetary oscillation domain. Detail analyses of the 24-oscillation mode additionally reveals significant Period modulation of the central period in the planetary domain. Results are consistent for all analyseddata sets (foEsand layer heights hEs).Wavelet based analysis of the wave activity within Es layer is completed by the stratospheric temperature measurements at 30 hPa, 20 hPa and 10 hPa.

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In this presentation is brought to you everything about the Czech beer:
• History
• Beer types
• Raw materials
• Production
• Beer composition
• How to enjoy beer

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The Liulin-5 active experiment for investigation of the radiation environment dynamics within the spherical tissue-equivalent phantom on the International Space Station (ISS) started in June 2007 on the Russian Segment of ISS. The Liulin-5 experiment is a part of the international project MATROSHKA-R on ISS. We present some results of data analysis for absorbed doses, linear energy transfer spectra and dose equivalents obtained in 2007- 2009 years at the mminimum of 23-rd Solar Cycle. These results are compared with measurements of other passive and active dosemetric instrumentation operating simultaneously on ISS.

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The newly discovered transient luminous events (TLE) in the strato/mesosphere above active thunderstorms are important phenomena which can influence the global atmospheric electric circuit, the chemical processes in the middle atmosphere, and can play a role in realization of the solar-terrestrial relationships. This explains the active investigations of TLE, and particularly, of red sprites. Sprites occur in the height interval ~45 - ~90 km up to tens ms after strong lightning discharges; usually these are positive cloud-to-ground (CG+) discharges above mesoscale convective systems at nighttime. Observations demonstrate that the sprites are composed, particularly in their lower part, of filaments formed by streamers, which are produced by strong quasi-electrostatic fields (QESF). These fields are a result of lightning discharges. The realization of streamers in the mesosphere needs an investigation of the conditions needed for their production. These conditions are examined here theoretically with respect to the parameters of the causative lightning discharges and of the atmospheric conductivity. First, in order to evaluate the streamer producing post-lightning QESF, an analytical approximation is proposed for the peak value of the QESF intensity with respect to its modification self-consistently with the variations of the atmospheric conductivity above 60 km where heating of free electrons occurs. Conditions are revealed by which positive streamers are formed and propagated downward, and their characteristics are estimated. Our calculations help us show why the lightning discharges with continuing currents produce streamers much more often than the ordinary lightning discharges.

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We will analyse the sunspot number time series in more detail with the main goal to make forecasts for the next solar cycle activity using the Box/Jenkins methodology for the model identification.

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The main goal of the presentation:
1. To explain of the Cochrane-Orcutt method to errror auto-correlation removing
2. To demonstrate how is working this method
3. Application of the method to climate data

However it is not the main goal to explain the global warming in detail