SIMONe Argentina: Exploring the MLT dynamics over southern Patagonia

Figure 1. A Google Earth sketch of SIMONe Argentina sites and
how it works (courtesy of Miguel Urco)
At mesosphere and lower thermosphere (MLT) altitudes (60-110 km), terrestrial weather meets the space weather. From stratospheric observations, strong gravity wave activity over the southern part of Argentina is known to occur.  On our search for understanding atmospheric coupling processes under different conditions, a few months ago we installed a new and novel multistatic specular meteor radar system in southern Patagonia, that we called SIMONe Argentina. About SIMONe, we  have already reported the preliminary results over northern Germany (see also Vierinen et al., 2019) and more recently over Peru. As in the case of SIMONe Peru, the system consists of one transmitter site with 5 transmitting antennas arranged in a Pentagon configuration, and 5 different receiving sites with one dual-polarization Yagi antenna each (see Figure 1 for a sketch of the installation and how it works).

SIMONe Argentina was installed, after a long customs process, in September 2019. Since then it has been operating with very few interruptions. In Figure 2 we can see a summary for February 2020. Here we show: the zonal and meridional winds from 75 to 105 km, the spatial distribution of the meteor detections (altitude, latitude and longitude), and the hourly counts for each of the links. Note that the link with most counts is Tres Lagos – El Calafate. As we say among us  “El Calafate rocks!!!”.
Figure 2. Summary plot of SIMONE Argentina multilink measurements. Note that the notorious oscillations in the winds are dominated by waves with 12-hour periods (courtesy of Mathias Clahsen).

Specific technical details about SIMONe, which uses a mix of MIMO, spread-spectrum, compressed sensing modern concepts in radar, can be found in Vierinen et al. (2016), Chau et al. (2019), Urco et al. (2019).

Once the equipment was out of customs, the installation of all 6 sites (1 for transmission and 5 for reception), was done in 2 weeks by a team led by Ralph Latteck and Jacobo Salvador. Below you can find a couple of composite pictures of antennas at most sites (Figure 3), as well as installation moments (Figure 4). 

Figure 3. Receiving sites at (a) Rio Gallegos, (b) El Chalten, (c) La Estela, and (d) Gobernador Gregores. The transmitter site (e) was installed at Tres Lagos.

Figure 4. Examples of installations by personnel from the Leibniz Institute of Atmospheric Physics (IAP): (a) Thomas Barth and Jens Wedrich enjoying the terrain at Tres Lagos, (b) Nico Pfeffer and Fede Conte tuning an  antenna and sun bathing, and (c) Fede Conte doing some sports while working.

The preliminary results are exciting. Not only we are able to provide characteristics of large-scale processes, but with this system we expect to explore the poorly understood mesoscale MLT dynamics over this region. The latter effort is being led by Fede Conte at IAP. An important not scientific point to stress, it is the time it took us to do the installation as well as the performance of the system. We have installed, essentially, the equivalent to five monostatic systems in 2 weeks!!!  Well done Ralph et al.!

The installation was done mainly by IAP personnel with the help of Jacobo Salvador, Nahuel Díaz, and Jonathan Quiroga. Besides the on-site staff, Juha Vierinen, Matthias Clahsen, Miguel Urco and myself contributed remotely. The support from our different hosts is really appreciated.

Figure 5. 
(a)    Thomas Barth, Nico Pfeffer, Jens Wedrich, Ralph Latteck, Fede Conte evaluating the possibility of a receiving site close to the glacier “El Perito Moreno”, (b) Fede Conte and Jacobo Salvador inspecting the IAP container at the transmitter site, and (c) Jacobo, Ralph, Fede and Nahuel Díaz on their way to El Chalten with a nice view of the peaks of “Cerro Torre” and “Mount Fitz Roy”.  NB: "El Perito Moreno" ice field  is the world's third largest reserve of fresh water.

SIMONe Argentina is an international effort lead by IAP in collaboration with the Universidad Nacional de la Patagonia Austral (Argentina), the Arctic University of Norway and the MIT Haystack Observatory  (USA).

We would like to sincerely thank Jacobo Salvador, Jonathan Quiroga and Nahuel Díaz (at UNPA, Río Gallegos); Darío Godoy and Facundo Olivares (at Tres Lagos); Pablo Quiroz (at La Estela); Martín “el griego” Palopoli y la gente de Parques Nacionales (at El Chaltén), and the Concejo Agrario de la Provincia de Santa Cruz (at Gob. Gregores and El Calafate). Without you guys SIMONe Argentina would not have been possible.