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The Chilean Observation Network De Meteor Radars (CONDOR) commenced deployment in June 2019 and became fully operational in February 2020. It is a multi-static meteor radar system consisting of three ∼ 1° latitudinally separated stations. The main (central) station is located at the Andes Lidar Observatory (ALO; 30.25° S, 70.74° W) and is used for both transmission and reception. The two remote sites are located to the north and south and are used for reception only. The southern station is located at the Southern Cross Observatory (SCO; 31.20° S, 71.00° W), and the northern station is located at the Las Campanas Observatory (LCO; 29.02° S, 70.69° W). The successful deployment and maintenance of CONDOR provide 24/7 measurements of horizontal winds in the mesosphere and lower thermosphere (MLT) and permit the retrieval of spatially resolved horizontal winds and vertical winds. This is possible because of the high meteor detection rates. Over 30 000 quality-controlled underdense meteor echoes are detected at the ALO site each day, and in total ∼ 88 000 events are detected each day over the three sites. In this paper, we present the configuration of the CONDOR system and discuss the validation and initial results of its data products. The motivations of deploying the CONDOR system also include combining measurements from other co-located ground-based instruments at the ALO site, which provide uniquely cross-validated and cross-scale observations of the MLT dynamics with multiple scientific goals.
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Mesosphere and Lower Thermosphere Changes Associated With the 2 July 2019 Total Eclipse in South America Over the Andes Lidar Observatory, Cerro Pachon, Chile
Abstract This article presents the results of a week of observations around the 2 July 2019, total Chilean eclipse. The eclipse occurred between 19:22 and 21:46 UTC, with complete sun disc obscuration at 20:38–20:40 UTC (16:38–16:40 LT) over the Andes Lidar Observatory (ALO) at (30.3°S, 70.7°W). Observations were carried out using ALO instrumentation with the goal to observe possible eclipse‐induced effects on the mesosphere and lower thermosphere region (MLT; 75–105 km altitude). To complement our data set, we have also utilized TIMED/SABER temperatures and ionosonde electron density measurements taken at the University of La Serena's Juan Soldado Observatory. Observed events include an unusual fast, bow‐shaped gravity wave structure in airglow images, mesosphere temperature mapper brightness as well as in lidar temperature with 150 km horizontal wavelength 24 min observed period, and vertical wavelength of 25 km. Also, a strong zonal wind shear above 100 km in meteor radar scans as well as the occurrence of a sporadic E layer around 100 km from ionosonde measurements. Finally, variations in temperature and density and the presence of a descending sporadic sodium layer near 98 km were seen in lidar data. We discuss the effects of the eclipse in the MLT, which can shed light on a sparse set of measurements during this type of event. Our results point out several effects of eclipse‐associated changes in the atmosphere below and above but not directly within the MLT.
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- PAR ID:
- 10367964
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Atmospheres
- Volume:
- 127
- Issue:
- 11
- ISSN:
- 2169-897X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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