The PhD student Alysson Brhian (PG-FIS/C) published the article "A Survey on Gravity Waves in the Brazilian Sector Based on Radiosonde Measurements From 32 Aerodromes" (https://agupubs.onlinelibrary.wiley.com/doi/epdf /10.1029/2023JD039811) in the renowned JGR: Atmosphere. The article was co-authored by his advisor, Prof. Marco Ridenti, co-supervisor Profª. Dr. Marisa Roberto (in memorian) and researchers Dr. Alessandro de Abre, Dr. José Guedes and Prof.
Gravity waves (GWs) - not to be confused with gravitational waves - are similar to ocean waves, which we often see on beaches, breaking over the sand. Just like ocean waves, GWs are generated by winds and have gravity as their restoring force. They play an important role in transporting energy and momentum over the atmosphere. The study of GWs is particularly relevant in the field of climatology.
This work analyzed data from meteorological balloons (radiosodes) from 32 Brazilian aerodromes maintained by the Brazilian airspace control institute (ICEA). The work used several statistical techniques that were new in this field and analyzed profiles from the troposphere and lower stratosphere layers. Data were analyzed in two seasonal periods: spring-summer and autumn-winter. The results showed that average wind profiles group latitudinally and present important seasonal variation. It was also shown that the kinetic and potential energies of GWs presented seasonality.
The study also showed that GWs are correlated up to approximately 3,500 km, for the same layer. On the other hand, no correlations were found between two layers, which suggests that waves hardly penetrate from one layer to another through the tropopause, at least for the studied spectral range. GW wave parameters such as vertical and horizontal wavelength, frequency, period and wave speed were also estimated for each seasonal period.
Based on the results, some implications for the problem of seeding plasma bubbles in the ionosphere were also discussed. For example, this work rules out the possibility that radiosonde gravity wave measurements could provide any useful information for predicting plasma bubbles on the ionosphere.
Atmospheric and spatial climatology is a rich field for the application of Complex Systems concepts and tools. This is a field of research presented in the ITA Physics postgraduate program, in the FIS-C concentration area (Nonlinear Dynamics and Complex Systems). For more information, see the FIS-C page.