Abstract. Six medium-scale gravity waves (GWs) with horizontal wavelengths of λ H =60-160 km were detected on four nights by Taylor et al. (2009) in the OH airglow layer near Brasilia, at 15 • S, 47 • W, during the Spread F Experiment (SpreadFEx) in Brazil in 2005. We reverse and forward ray trace these GWs to the tropopause and into the thermosphere using a ray trace model which includes thermospheric dissipation. We identify the convective plumes, convective clusters, and convective regions which may have generated these GWs. We find that deep convection is the highly likely source of four of these GWs. We pinpoint the specific deep convective plumes which likely excited two of these GWs on the nights of 30 September and 1 October. On these nights, the source location/time uncertainties were small and deep convection was sporadic near the modeled source locations. We locate the regions containing deep convective plumes and clusters which likely excited the other two GWs. The last 2 GWs were probably also excited from deep convection; however, they must have been ducted ∼500-700 km if so. Two of the GWs were likely downwards-propagating initially (after which they reflected upwards from the Earth's surface), while one of the GWs was likely upwards-propagating initially from the convective plume/cluster. We also estimate the amplitudes and vertical scales of these waves at the tropopause, and compare their scales with those from a simple, linear convection model. Finally, we calculate each GW's dissipation altitude, location, and amplitude. We find that the dissiCorrespondence to: S. L. Vadas (vasha@cora.nwra.com) pation altitude depends sensitively on the winds at and above the OH layer. We also find that several of these GWs may have penetrated to high enough altitudes to potentially seed equatorial spread F (ESF) if located somewhat farther from the magnetic equator.
Abstract. We developed a technique to identify and estimate the size, intensity, and Tropopause overshoot of thunderstorm convective cores expected to be significant sources of gravity waves. The work was based on GOES IR images of South America on the night of 30 September to 1 October and 25–26 October 2005, as part of the Spread F Experiment (SpreadFEx) in Brazil in 2005. We also characterized, for the first time, the convective activity of three small TLE producing thunderstorms that yielded 11 TLEs on 25–26 October 2005. The campaign occurred during the dry to wet season transition in central Brazil, marked by the presence of extra-tropical cyclogenesis over the Atlantic Ocean, and cold fronts penetrating inland. The Tropopause temperature was typically −76°C with a corresponding altitude of ~15 200 m. Vigorous convective cores capable of generating strong gravity waves were located in convective regions having areas with cloud top temperatures ≤−76°C. They had typical cloud-top temperature deficits of ΔT−2.0°C to −8.0°C from the average surroundings, implying overshoot heights of 200 to 3100 m, which are within the typical range. Fast vertical development and high horizontal growth rates were associated with a large number of simultaneously active vigorous convective cores, indicating that their dynamics may have determined the spatial-temporal development of the thunderstorms analyzed. Moderate convective cores were also present in areas with cloud top −76°C≤T≤−70°C. They had ΔT of −1.9°C to −5.3°C producing overshoots between 80–300 m. All convective cores had typical diameters of 5–20 km and their size tended to increase with ΔT, there was a 57% correlation between the two parameters. Analysis of the relationship of cloud top T with positive and negative cloud-to-ground lightning (+/−CG) occurrence rate and with peak current showed that lighting activity may provide an independent way to identify convective cores and measure their intensity, since they were characterized by a high incidence of low peak current −CGs that forms the bulk of the −CG population.
Figure 4 of the mentioned paper, which is an atmospheric temperature profile, was accidentally replaced by a corrected version of
ResumoEste trabalho tem como objetivo demonstrar uma aplicação prática da técnica de reconciliação de dados no diagnóstico das medições que compõe uma malha de distribuição de gás BFG -Blast Furnace Gas. Falhas comuns de medição tais como saturação e congelamento da indicação afetam a qualidade da informação e este tipo de detecção faz parte da proposta de diagnóstico. Será abordado o desenvolvimento de um algoritmo que implementa a técnica de reconciliação, bem como a elaboração de uma matriz de diagnóstico no InfoPlus.21. Os principais indicadores deste diagnóstico são armazenados na base de dados do InfoPlus.21 visando consultas históricas e monitoramento contínuo das medições. Os dados obtidos demonstraram que a técnica de reconciliação de dados pode contribuir para identificação de falhas e agregar confiabilidade às medições. Palavras-chave: Confiabilidade; Diagnóstico; Reconciliação de dados. APPLICATION OF DATA RECONCILIATION TECHNIQUE FOR MEASUREMENTS DIAGNOSIS AbstractThis work proposes a practical application of data reconciliation technique in the diagnosis of the measurements that comprise a network of gas distribution BFG -Blast Furnace Gas. Measurements with faults such as saturation or frozen indication can affect the quality of information and this type of detection is part of the proposed diagnosis. The development of an algorithm that implements this technique and also a diagnosis tool implemented on InfoPlus.21 will be showed. The main indicators of this diagnosis are stored on InfoPlus.21 database to allow historical queries and continuous monitoring measurements. The results show that using this technique is possible to contribute with fault identification and aggregate reliability of the measurements.
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