Semestral Journal of Centro Argentino de Meteorólogos, which is published  since 1970 and serves on the Core of Argentine Scientific Journals since 2005. Meteorologica publishes original papers in the field of atmospheric sciences and oceanography.

Registration number of intellectual property: RL-2018-42420861-APN-DNDA#MJ

ISSN 1850-468X

Volume 45 N° 1 MORE NOTES FROM THIS ISSUE

DESCRIPTION OF ATMOSPHERIC GRAVITY WAVES IN THE BUENOS AIRES COAST, ARGENTINA

Iael Pérez, Walter Dragani, Marcos Saucedo, Alejandro Godoy, Bibiana Cerne, y Paula Martín

Servicio de Hidrografía Naval (Ministerio de Defensa)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
Departamento de Ciencias de la Atmósfera y los Océanos (FCEyN-UBA)
Servicio Meteorológico Nacional (Ministerio de Defensa)
Instituto Franco-Argentino para el Estudio del Clima y sus Impactos (UMI IFAECI/CNRS-CONICET/CIMA/UBA)
Universidad Nacional de la Plata (UNLP)
Departamento de Geografía (FFyL-UBA)

Manuscript received on March 13th, 2018 and on final form on September 27th, 2018

ABSTRACT

High-frequency perturbations of the atmospheric pressure (atmospheric gravity waves, AGW) measured at Mar del Plata in 2013 are studied in the present paper. Implementing the wavelet spectral method it was obtained that the duration of the active lapses, the spectral structure, the energy and the amplitudes of AGW are different for each event. It was found that, in general, active events last between 5 and 20h and that the maximum pressure fluctuations range between 0.5 and 2 hPa, with typical oscillations between 30 and 150 min. From the 37 active cases of AGW, it was established that 24 are associated with cold fronts, 9 with warm fronts, and 4 are related to other synoptic systems. It was found that most of the events occur when the frontal zone is located at the northern Patagonia and moves towards the E or NE. The Weather Research and Forecasting (WRF) model was implemented and two cases were simulated. In the first case, a cold front and a cyclone located at the southern Buenos Aires Province and on the ocean were observed. In contrast, in the second case, a warm front was observed at the southern Buenos Aires Province, which then moved towards the NW as a cold front. The results achieved with the WRF model indicate that the predominant direction of propagation in the coastal region of Buenos Aires could be towards E-NE, in disagreement with the available scarce background for the region indicating that the direction of propagation could be towards the ESE-SE.