Browsing by Author "Reyes, P. M."

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    High-resolution observations of mesospheric layers with the Jicamarca VHF Radar
    (Elsevier, 2007) Lehmacher, G. A.; Guo, L.; Kudeki, E.; Reyes, P. M.; Akgiray, A.; Chau Chong Shing, Jorge Luis
    We report new results from the 50-MHz Jicamarca radar in Peru (12°S, 77°W), which is able to observe backscatter from the daytime mesosphere on any given day. Since 2005, the radar has been operated in a high-power MST-ISR mode for 3-day runs four times per year to study the seasonal variation of mesospheric echoes. Doppler spectra are obtained with 1 min and 150-m nominal resolution yielding power, horizontal and vertical winds, and spectral width. The rich echo structures contain braids and billows suggestive of Kelvin–Helmholtz instability (KHI). We present three cases; (1) a short sequence of billows growing in height and becoming unstable; (2) a long train of billows showing high levels of turbulence at two different locations; and (3) a series of billows passing only slowly through the field of view. In all cases, the layers were associated with strong wind shears, mature billows were 1–1.5 km tall, and separation of KH phase fronts was 8–10 km. We compare our observations with OH imager observation and numerical simulations.
    Palabras clave:Equatorial mesosphereVHF radarVHF echoes
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    The equatorial ionosphere over Jicamarca during the January 2009 sudden stratospheric warming
    (Instituto Geofísico del Perú, 2009) Chau Chong Shing, Jorge Luis; Galindo, F. R.; Milla, Marco; Kudeki, E.; Reyes, P. M.; Goncharenko, L. P.; Fejer, B. G.
    Diapositivas presentadas en 2009 Joint Assembly. The Meeting of the Americas. 24-27 May 2009. Toronto, Ontario, Canada.
    Palabras clave:Geophysical observatoriesIonosphereStratosphere