55 research outputs found
Progress in space weather modeling in an operational environment
This paper aims at providing an overview of latest advances in space weather modeling in an operational environment in Europe,
including both the introduction of new models and improvements to existing codes and algorithms that address the broad range of space weatherās prediction requirements from the Sun to the Earth. For each case, we consider the modelās input data, the output
parameters, products or services, its operational status, and whether it is supported by validation results, in order to build a solid basis for future developments. This work is the output of the Sub Group 1.3 āāImprovement of operational modelsāā of the European Cooperation in Science and Technology (COST) Action ES0803 āāDeveloping Space Weather Products and services in Europeāā and therefore this review focuses on the progress achieved by European research teams involved in the action
Thermospheric heating at high latitudes as observed from intercosmos-Bulgaria-1300 and dynamics explorer-B
This paper reports the results of the first direct comparison of near simultaneous measurements obtained by the INTERCOSMOS-BULGARIA-1300 and the DYNAMICS EXPLORER-B satellites. The ICB-1300 is in a near circular orbit at a mean height of about 850 km. The DE-B satellite in an elliptical orbit is sometimes directly below the ICB-1300 satellite providing an opportunity to investigate the response of the thermosphere to particle fluxes from the magnetosphere. Energy fluxes in the range 0.2-15 keV are obtained from an energetic particle analyzer on board the ICB-1300 satellite. The thermospheric composition and density are obtained by a neutral gas mass spectrometer (NACS) on the DE-B satellite. During the period 20 August-20 November, 1981, observations show tht the times and locations of maxima in magnetospheric energy deposition coincide with regions of maximum thermospheric upwelling characterized by composition changes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25883/1/0000446.pd
Near-Earth space plasma modelling and forecasting
In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS)in the Working Package 1.3, new ionospheric models, prediction and forecasting methods and programs as well as ionospheric imaging techniques have been developed. They include (i) topside ionosphere and meso-scale irregularity models, (ii) improved forecasting methods for real time forecasting and for prediction of foF2,
M(3000)F2, MUF and TECs, including the use of new techniques such as Neurofuzzy, Nearest Neighbour, Cascade Modelling and Genetic Programming and (iii) improved dynamic high latitude ionosphere models through tomographic imaging and model validation. The success of the prediction algorithms and their improvement over
existing methods has been demonstrated by comparing predictions with later real data. The collaboration between different European partners (including interchange of data) has played a significant part in the development and validation of these new prediction and forecasting methods, programs and algorithms which can be applied to a variety of practical applications leading to improved mitigation of ionosphereic and space weather effects
Near-Earth space plasma modelling and forecasting
In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS)in the Working Package 1.3, new ionospheric models, prediction and forecasting methods and programs as well as ionospheric imaging techniques have been developed. They include (i) topside ionosphere and meso-scale irregularity models, (ii) improved forecasting methods for real time forecasting and for prediction of foF2,
M(3000)F2, MUF and TECs, including the use of new techniques such as Neurofuzzy, Nearest Neighbour, Cascade Modelling and Genetic Programming and (iii) improved dynamic high latitude ionosphere models through tomographic imaging and model validation. The success of the prediction algorithms and their improvement over
existing methods has been demonstrated by comparing predictions with later real data. The collaboration between different European partners (including interchange of data) has played a significant part in the development and validation of these new prediction and forecasting methods, programs and algorithms which can be applied to a variety of practical applications leading to improved mitigation of ionosphereic and space weather effects.Published255-2713.9. Fisica della magnetosfera, ionosfera e meteorologia spazialeJCR Journalope
Solar activity impact on the Earthās upper atmosphere
The paper describes results of the studies devoted to the solar activity impact on the Earthās upper atmosphere and ionosphere,
conducted within the frame of COST ES0803 Action.
Aim: The aim of the paper is to represent results coming from different research groups in a uniļ¬ed form, aligning their speciļ¬c topics into the general context of the subject.
Methods: The methods used in the paper are based on data-driven analysis. Speciļ¬c databases are used for spectrum analysis,
empirical modeling, electron density proļ¬le reconstruction, and forecasting techniques.
Results: Results are grouped in three sections: Medium- and long-term ionospheric response to the changes in solar and geomag-
netic activity, storm-time ionospheric response to the solar and geomagnetic forcing, and modeling and forecasting techniques.
Section 1 contains ļ¬ve subsections with results on 27-day response of low-latitude ionosphere to solar extreme-ultraviolet (EUV)
radiation, response to the recurrent geomagnetic storms, long-term trends in the upper atmosphere, latitudinal dependence of total electron content on EUV changes, and statistical analysis of ionospheric behavior during prolonged period of solar activity.
Section 2 contains a study of ionospheric variations induced by recurrent CIR-driven storm, a case-study of polar cap absorption
due to an intense CME, and a statistical study of geographic distribution of so-called E-layer dominated ionosphere.
Section 3 comprises empirical models for describing and forecasting TEC, the F-layer critical frequency foF2, and the height of
maximum plasma density. A study evaluates the usefulness of effective sunspot number in specifying the ionosphere state. An
original method is presented, which retrieves the basic thermospheric parameters from ionospheric sounding data
Review of progress in gathering, distributing, and using satellite data for activities within PRIME
Recent progress in using the satellite data for various PRIME (Prediction and Retrospective Ionospheric Modelling over Europe) purposes is briefly presented. The satellite data base is already in operation and contains data of local plasma and neutral atmosphere parameters taken from several ionospheric satellites. A method of tracing the locally measured parameters along the magnetic field lines down to hmF2 is developed using a theoretical F-region code. This method is applied to receive foF2sat needed to test monthly median and instantaneous mapping methods. In order to reduce the uncertainties arising from the unknown photoionization and recombination rates, foF2 is calibrated at one point on the satellite orbit with a Vertical Incident (VI) foF2 and their ratio is then assumed constant along the whole satellite track over the PRIME area. The testing procedure for monthly median maps traces the measured plasma density down to a basic height of 400 km, where individual foF2sat values are accumulated in every time/subarea bin within the given month, then their median is calibrated with the available medians from the VI ionosonde network. From all available satellite orbits over the PRIME area, 35 of them were found to pass over two VI ionosonde stations. The second station in these orbits was used to check the calculated foF2sat with the measured VI foF2. The standard deviation was found to be only 0.15 MHz
Review of progress in gathering, distributing and using satellite data for activities within COST 238 (PRIME)
Recent progress in using the satellite data for various PRIME purposes is briefly presented. The satellite data base is already in operation and contains data of local plasma and neutral atmosphere parameters taken from several ionospheric satellites. A method of tracing the locally measured parameters along the magnetic field lines down to hmF2 is developed using a theoretical F-region code. This method is applied to receive f0F2sat needed to test monthly median and instantaneous mapping methods. In order to reduce the uncertainties arising from the unknown photoionization and recombination rates, f0F2 is calibrated at one point on the satellite orbit with a Vertical Incident (VI) f0F2 and their ratio is then assumed constant along the whole satellite track over the PRIME area. The testing procedure for monthly median maps traces the measured plasma density down to a basic height of 400 km, where individual f0F2sat values are accumulated in every time/subarea bin within the given month, then their median is calibrated with the available medians from the VI ionosonde network. From all available satellite orbits over the PRIME area, 35 of them were found to pass over two VI ionosonde stations. The second station in these orbits was used to check the calculated f0F2sat with the measured VI f0F2. The standard deviation was found to be only 0.15 MHz
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