Research lines on Aeronomy in RAPEAS different groups:

GESA (Spatial Geodesy and  Aeronomy) Research Group : Facultad de Ciencias Astronómicas y Geofísicas (FCAG) ,Universidad Nacional de La Plata (UNLP):

 La Plata  Ionospheric Model (LPIM):

LPIM is a global model used for the description of the time- space variability of free electrons in Ionosphere (Fig. 1). Its development has taken more than 20 years of continuous work and its projection into the future is still unlimited.


 

                                               





                         Figure 1.  Global distribution of Total Vertical Content of Electrons and vertical  distribution of electrons density in the area
                         Equatorial Anomaly assessed with LPIM.

Instruments:

With the cooperation of scientists from USA, GESA has installed a ionospheric sounder in La Plata (Buenos Aires), which makes it possible to characterise ionospheric variability at different altitudes and a meteor radar in Río Grande (Tierra del Fuego),  which makes it possible to characterise the flow of meteors  entering the atmosphere.

 AIRES project:

GESA is the main scientific group from  Argentina involved in  AIRES  project (Argentina Ionosphere Radar Experiment Station). Its aim is to install and operate an Incoherent Scatter Radar  at the conjugated magnetic point in Arecibo Observatory, situated La Plata (Fig. 6). AIRES has the support of the American National Foundation of Sciences and CONICET in Argentina. AIRES will be one of the few incoherent scatter radars existent  in the southern hemisphere..

Institute of  Astronomic, Earth and Spatial Sciences (ICATE)-CONICET-UNSJ:

 ICATE research projects address, in general, the following aspects of  ionosphere: (1) Climatology, ionospheric meteorology , (2) ionospheric modelling, (3) Coupling of Ionosphere with troposphere and magnetosphere.

Ionospheric Climatology:

The average conditions of the main ionospheric parameters are studied. Such parameters _ electronic density and total electronic content_ define ionospheric behaviour. Variations of ionospheric variables are also studied: temporary variations (according to the time of day, season and solar activity) and spatial variations (geographical position).

 In general, “ionospheric weather” has been more widely studied at mid latitudes, although greater effort is needed to characterise ionosphere more adequately in regions of low and high latitudes..

Ionospheric Meteorology:

The variations in solar activity and plasma emissions from the sun cause dramatic changes in spatial environment around the earth. These changes make up “space weather” or “spatial meteorology”.

From the point of view of spatial meteorology and its effects on human activity, the most important meteorologic phenomena are those which significantly set ionosphere aside from its average weather conditions. Examples of such phenomena are sudden ionospheric disruptions (SID), ionopheric storms, ionospheric sparkling, spread F, among others.

 The knowledge of meteorologic variations is not developed enough. Therefore, it is necessary to analyse more deeply the chemical and physical processes  that take place in the natural laboratory  represented by the earth's upper atmosphere, under constant solar radiation..

 Ionosphere in Argentina is under the effects of equatorial and South Atlantic anomalies, which bring about great complexity and variability in ionospheric meteorology of the region/area. For this reason, this study is important.

 From the technologic point of view, the country needs to acquire advanced systems of satellite navigation, in order to optimise air, sea and land traffic management,. Such systems must be able to correct ionospheric effect on them. This is why thorough knowledge about ionospheric behaviour is essential.

Ionospheric Modelling:

Nowadays Ionospheric modelling represents a very important chapter in the study of ionosphere.

Nowadays, most of ionospheric models can reproduce/ replicate quite accurately the features of ionospheric weather represented by variations of time of day, season and solar activity in a given site or area. However, due to the reasons mentioned above, no model is capable of reproducing meteorologic variations in ionosphere.

 Ionospheric models can be divided into: theoretical, empirical or semi empirical, such as International Reference Ionosphere  (IRI) and “analytic profilers”, such as NeQuick.

The two models mentioned as examples are updated in regular meetings, taking into account experimental evidence. As Argentinian  members of the International Group for IRI model, we have the opportunity to constantly interact and work with colleagues from other parts of the globe.

Magnetosphere -ionosphere -troposphere coupling and its impact on ionospheric variability

As communication systems have become more sensitive, interest in time space variability has increased over the last years.  Possible sources of ionosphere variability can be reduced to/ grouped into three categories: solar, meteorological  and geomagnetic. However, there is increasing evidence of ionosphere coupling with regions below (troposphere) and above (magnetosphere). At mid latitudes, the influence of processes coming from the lower atmosphere, provoke oscillations whose periods range from hours to minutes and even seconds. Gravity waves play a very important role in upper atmosphere. These waves have different origins: meteorological (they come mainly from troposphere and are originated by meteorological phenomena, such as cold fronts, hurricanes, tornadoes, cyclones, flow of topography (mountain waves) among others.

 The objective in this field is to stimulate and strengthen research and technologic development, oriented to the study of magnetosphere, ionosphere, troposphere relationships, to support the formation of human resources in order to boost technology in this area, with the help of different groups from abroad, and to enhance the use of instrumental facilities existent in Argentina ( ionospheric sounders, receptors GPS, magnetometers, etc.) to be installed in the future (two HF Doppler systems, from the Czech Republic).

 In order to reach these aims, we are creating a bilateral project with the Czech Republic, which will use past and present experimental data, planned future measurements obtained through different techniques, as well as atmospheric/meteorological data networks, from world centres.

Telecommunications Laboratory in the Departament of  Electricity, Electronics and  Computer Science,   FACET-UNT:

The main research topics of this  Laboratory are:

- Occurrence analysis of ionospheric spread (spread F) in low latitude.

- Signals processing for detection of echoes in geophysical radars.

- Studies on radio propagation in ionized media for OTH radar applications.

- Detection and allocation of atmospheric discharges.

- Modelling of antennas arrangements for incoherent scatter radars.

 (the Laboratory) manages and takes part in research projects:

 Current National Projects:

                    “Study and Modelling of Ionospheric Magnitudes for Communications Systems and Satellite Navigation”. 26/E408. CIUNT, UNT. (2008-2012). Director: M. A. Cabrera.

                    “Argentinian Network for the Study of Upper Atmosphere (RAPEAS). CONICET, Res: 2339/2011. (2011-2013).

                    “Research applied to mid and high earth atmosphere as a form of contribution to communication , satellite navigation, and to weather change.” FONCYT, (2011-2014). Director: M. A. Cabrera.

                    “Development of a prototype of an Argentinian  Digital Ionospheric Sounder”. Under secretariat of Technologic Research and Development  M.D.R.A. (2012-2014). Director: M. A. Cabrera

Current  Bilateral Projects  and International Cooperation:

“Magnetosphere - ionosphere-troposphere coupling and its impact on ionospheric variability”, Institute of Atmospheric Physics, Czech Republic, Directors: Marta Mosert (CONICET) and Dalia Buresova (UFA- Czech R) (2012-2014). Objective: Installation of Doppler measurement systems in HF band for ionospheric disruption measurement.

 

 Physics Department Group of  FACET-UNT, formed by Ana G. Elias, Marta Zossi de Artigas, Gustavo A. Mansilla and  Blas de Haro Barbas:

“Variability and tendencies/ trends in mid and upper atmosphere” are studied. Determination / assessment of long term variations in mid and high atmosphere parameters as a result of natural causes. The atmospheric parameters studied are mainly ionospheric and stratospheric, and the natural causes considered are: secular variation in the earth magnetic field, geomagnetic activity and solar activity.  The main purpose of this study is to contribute to the issue : Weather Change, which is, according to IPCC (Intergovernmental Panel on Climate Change): “any weather change throughout time, due to natural variability or human activity”.

           We intend to resolve  inconsistencies, reduce uncertainty and achieve deeper understanding of weather change.

           Two specific topics on which we are working are:

- Tendencies which are observed in low latitude, equatorial region, where the situation is more complex due to equatorial anomaly and secular movement/ displacement of magnetic equator .

-  Theoretical and statistical  analysis of the effect of secular variations on the earth magnetic field. over conductivity in ionosphere and layer E ionospheric flows.

 We have also worked on:

- Analysis of associations between stratospheric parameters (temperature, ozone content, winds) and solar /geomagnetic activity in order to state coupling between this layer and lower atmospheric regions (troposphere) and upper (ionosphere, termosphere) through solar and geomagnetic activity on them.

 - Study of association between geomagnetic/ solar activities and local stratospheric wind QBO through statistical experiments and analysis of possible physical causes.

 Radio propagation Division – Army’s Research Direction (DIIV):

The backbone lines of development are:

                    Spread of electromagnetic  waves.

                    Measurement and interpretation of ionospheric parameters .

                    Scatter of electromagnetic waves.

This is the only national body/ institution that produces ionospheric  predictions/ forecasts. Its services are used by the Army, Security forces, governmental agencies and private companies.

 The Division can carry out measurements of field intensity from VLF band to hasta SHF and undertake studies on electromagnetic compatibility.

 Electric field- strength meters, spectrum analysers and calibrated antennas (from VLF to SHF) are available for such measurements.