scholarly journals Case study of mesospheric front dissipation observed over the northeast of Brazil

2018 ◽  
Vol 36 (2) ◽  
pp. 311-319 ◽  
Author(s):  
Amauri Fragoso Medeiros ◽  
Igo Paulino ◽  
Cristiano Max Wrasse ◽  
Joaquim Fechine ◽  
Hisao Takahashi ◽  
...  

Abstract. On 3 October 2005 a mesospheric front was observed over São João do Cariri (7.4∘ S, 36.5∘ W). This front propagated to the northeast and appeared in the airglow images on the west side of the observatory. By about 1.5 h later, it dissipated completely when the front crossed the local zenith. Ahead of the front, several ripple structures appeared during the dissipative process of the front. Using coincident temperature profile from the TIMED/SABER satellite and wind profiles from a meteor radar at São João do Cariri, the background of the atmosphere was investigated in detail. On the one hand, it was noted that a strong vertical wind shear in the propagation direction of the front produced by a semidiunal thermal tide was mainly responsible for the formation of duct (Doppler duct), in which the front propagated up to the zenith of the images. On the other hand, the evolution of the Richardson number as well as the appearance of ripples ahead of the main front suggested that a presence of instability in the airglow layer that did not allow the propagation of the front to the other side of the local zenith. Keywords. Atmospheric composition and structure (airglow and aurora) – meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

2018 ◽  
Vol 36 (1) ◽  
pp. 253-264 ◽  
Author(s):  
Gabriel Augusto Giongo ◽  
José Valentin Bageston ◽  
Paulo Prado Batista ◽  
Cristiano Max Wrasse ◽  
Gabriela Dornelles Bittencourt ◽  
...  

Abstract. The main goals of this work are to characterize and investigate the potential wave sources of four mesospheric fronts identified in the hydroxyl near-infrared (OH-NIR) airglow images, obtained with an all-sky airglow imager installed at Comandante Ferraz Antarctic Station (EACF, as per its Portuguese acronym) located on King George Island in the Antarctic Peninsula. We identified and analyzed four mesospheric fronts in 2011 over King George Island. In addition, we investigate the atmospheric background environment between 80 and 100 km altitude and discuss the ducts and propagation conditions for these waves. For that, we used wind data obtained from a meteor radar operated at EACF and temperature data obtained from the TIMED/SABER satellite. The vertical wavenumber squared, m2, was calculated for each of the four waves. Even though no clearly defined duct (indicated by positive values of m2 sandwiched between layers above and below with m2  < 0) was found in any of the events, favorable propagation conditions for horizontal propagation of the fronts were found in three cases. In the fourth case, the wave front did not find any duct support and it appeared to dissipate near the zenith, transferring energy and momentum to the medium and, consequently, accelerating the wind in the wave propagation direction (near to south) above the OH peak (88–92 km). The likely wave sources for these four cases were investigated by using meteorological satellite images and in two cases we could find that strong instabilities were potential sources, i.e., a cyclonic activity and a large convective cloud cell. In the other two cases it was not possible to associate troposphere sources as potential candidates for the generation of such wave fronts observed in the mesosphere and secondary wave sources were attributed to these cases. Keywords. Atmospheric composition and structure (airglow and aurora) – meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)


2003 ◽  
Vol 21 (8) ◽  
pp. 1869-1878
Author(s):  
C.-F. Enell ◽  
U. Brändström ◽  
B. Gustavsson ◽  
S. Kirkwood ◽  
K. Stebel ◽  
...  

Abstract. The formation of polar stratospheric clouds (PSCs) is closely related to wave activity on different scales since waves propagating into the stratosphere perturb the temperature profile. We present here a case study of the development of visible PSCs (mother-of-pearl clouds), appearing at the polar vortex edge on 9 January 1997, under-taken by means of ground-based cameras. It is shown that the presence of stratospheric clouds may be detected semi-automatically and that short-term dynamics such as altitude variations can be tracked in three dimensions. The PSC field showed distinct features separated by approximately 20 km, which implies wave-induced temperature variations on that scale. The wave-induced characteristics were further emphasised by the fact that the PSCs moved within a sloping spatial surface. The appearance of visible mother-of-pearl clouds seems to be related to leewave-induced cooling of air masses, where the synoptic temperature has been close to (but not necessarily below) the threshold temperatures for PSC condensation.Key words. Atmospheric composition and structure (aerosols and particles) – Meteorology and atmospheric dynamics (middle atmosphere dynamics; instruments and techniques)


2018 ◽  
Vol 59 (1) ◽  
pp. 65-79
Author(s):  
Katarzyna Nikorowicz-Zatorska

Abstract The present paper focuses on spatial management regulations in order to carry out investment in the field of airport facilities. The construction, upgrades, and maintenance of airports falls within the area of responsibility of local authorities. This task poses a great challenge in terms of organisation and finances. On the one hand, an active airport is a municipal landmark and drives local economic, social and cultural development, and on the other, the scale of investment often exceeds the capabilities of local authorities. The immediate environment of the airport determines its final use and prosperity. The objective of the paper is to review legislation that affects airports and the surrounding communities. The process of urban planning in Lodz and surrounding areas will be presented as a background to the problem of land use management in the vicinity of the airport. This paper seeks to address the following questions: if and how airports have affected urban planning in Lodz, does the land use around the airport prevent the development of Lodz Airport, and how has the situation changed over the time? It can be assumed that as a result of lack of experience, land resources and size of investments on one hand and legislative dissonance and peculiar practices on the other, aviation infrastructure in Lodz is designed to meet temporary needs and is characterised by achieving short-term goals. Cyclical problems are solved in an intermittent manner and involve all the municipal resources, so there’s little left to secure long-term investments.


Author(s):  
Luigia Mocerino ◽  
Franco Quaranta

The scope of this work is to try to quantify the reduction of emissions due to COVID-19; an analysis covering the entire port of Naples will be presented. The explosion of the global pandemic from SARS-CoV-2 led to the adoption of local and global countermeasures aimed at containing contagions. The transportation sector, and in particular the passenger moving sector, was deeply affected; this almost total block of movements between regions and countries if, on the one hand, seriously slowed the economy, on the other, it drastically reduced the emissions on a global and local scale. In this work, the case study of the cruise ships berthed at the Maritime Station (Stazione Marittima) in the port of Naples is examined. The traffic of cruise ships during the lockdown and in the immediately following months was analysed and compared first with respect to the calendars scheduled for the same period and then with respect to the same months of 2019. The reduction in number of cruise ships and passengers were analysed and compared to the previous trends. The vessels collected, for 2019 and 2020 (both those that arrived and those that suffered the effects of the movement block) were subsequently characterized in terms of power and speed. Finally, an estimate of the emissions of NOX, SOX, CO2 produced and saved was carried out. The 2020 results will be compared with the hypothetical emissions that would have occurred in the absence of the lockdown and with those of the same period of the previous year.


2001 ◽  
Vol 19 (5) ◽  
pp. 563-569 ◽  
Author(s):  
J. Gumbel

Abstract. Meshes are commonly used as part of instruments for in situ atmospheric measurements. This study analyses the aerodynamic effect of meshes by means of wind tunnel experiments and numerical simulations. Based on the Direct Simulation Monte Carlo method, a simple mesh parameterisation is described and applied to a number of representative flow conditions. For open meshes freely exposed to the flow, substantial compression effects are found both upstream and downstream of the mesh. Meshes attached to close instrument structures, on the other hand, cause only minor flow disturbances. In an accompanying paper, the approach developed here is applied to the quantitative analysis of rocket-borne density measurements in the middle atmosphere.Key words. Atmospheric composition and structure (instruments and techniques; middle atmosphere – composition and chemistry)


Author(s):  
Enrico Baraldi ◽  
Giancarlo Nadin

This chapter relies on a case study featuring the business network around Stella, an Italian home textile manufacturer, to illustrate the challenging issue of engaging other firms into complex “Network Process Re-engineering” (NPR) projects. While the strict technological dimension of selecting, developing, and implementing ICT solutions is certainly very important and poses several challenges to this type of projects, this chapter focuses on other types of challenges, namely those pertaining to the nature and quality of relationships between the actors taking part in a NPR project. We stress the importance of the connection between the specific inter-organizational activities that need to be redesigned and coordinated in better ways, on the one hand, and the bonds existing among the actors, on the other hand. We suggest that very advanced and complex coordination tasks, entailing sensitive communication patterns, can be tackled only if supported by strong, integrative relationships characterized by high trust and commitment between the involved parties. We conclude by discussing how the pivotal firms or the “strategic centers” of a network can support and facilitate complex change projects like NPR by carefully combining different strategies, whereby they both exert coercive power and make concessions to their counterparts in the network.


2002 ◽  
Vol 20 (4) ◽  
pp. 559-564
Author(s):  
A. V. Mikhalev ◽  
M. A. Chernigovskaya ◽  
A. Yu. Shalin ◽  
E. S. Kazimirovsky

Abstract. The results of spectral measurements of the daily near-noon surface direct solar ultraviolet radiation in the wavelength range of 295–345 nm obtained in Irkutsk (East Siberia) for the time interval of 1998–2000 are presented. For the period under consideration, the seasonal UV radiation variations are analysed that are associated with the total ozone dynamics, the transition of cyclonic and anticyclonic (Siberian anticyclone) periods, the presence of snow cover, and other factors. The analysis reveals an asymmetric behaviour of the seasonal course in ground-level UV radiation around the time of the summer solstice, with seasonal variation dependence on the wavelength. We have determined the irregular variations of surface UV radiation that is typical for the region, with their properties dependent on the season and on the spectral range analysed. The similarity of the above noted features from year to year was revealed.Key words. Atmospheric composition and structure (Transmission and scattering of radiation; instruments and techniques) – Meteorology and atmospheric dynamics (middle atmosphere dynamics)


2019 ◽  
Vol 11 (18) ◽  
pp. 5128 ◽  
Author(s):  
Małgorzata Zdon-Korzeniowska ◽  
Monika Noviello

In the modern economy, there is a significant increase in interest in tourism, both at the level of states, regions, communes and individual places. Tourism is seen primarily as an opportunity for economic development, but also for social development and activation of local communities. Well-managed tourism can become a way to preserve and protect the natural, cultural and historical heritage of specific places or regions by exploring and nurturing it. Heritage elements become, on the one hand, attractions around which unique tourism products are created, and on the other hand, a kind of distinguishing feature of a given place or region, based on which local communities build their identity and sense of belonging. The concept of creating regional tourism products could integrate these two factors, i.e., tourism and heritage. The article presents the concept of a regional tourist product on the example of the Wooden Architecture Route (case study).


Author(s):  
Giulia Terzian

Abstract The starting point of this paper is a claim defended most famously by Graham Priest: that given certain observed similarities between the set-theoretic and the semantic paradoxes, we should be looking for a ‘uniform solution’ to the members of both families. Despite its indisputable surface attractiveness, I argue that this claim hinges on a problematic reasoning move. This is seen most clearly, I suggest, when the claim and its underlying assumptions are examined by the lights of a novel, quite general and, I contend, promising take on inter-theoretic analogy. The ensuing discussion is intended to serve as both a possible case study and a first step towards the broader aim of the paper: namely, to initiate a wider conversation on the methodology of paradox-solving on the one hand, and the use of inter-theoretic analogies on the other.


2019 ◽  
Vol 30 (4) ◽  
pp. 1187-1220
Author(s):  
Francisco de Abreu Duarte

Abstract This article develops the concept of the monopoly of jurisdiction of the Court of Justice of the European Union (CJEU) through the analysis of the case study of the Investment Court System (ICS). By providing a general framework over the criteria that have been developed by the Court, the work sheds light on the controversial principle of autonomy of the European Union (EU) and its implications to the EU’s external action. The work intends to be both pragmatic and analytical. On the one hand, the criteria are extracted as operative tools from the jurisprudence of the CJEU and then used in the context of the validity of the ICS. This provides the reader with some definitive standards that can then be applied to future cases whenever a question concerning autonomy arises. On the other hand, the article questions the reasons behind the idea of the monopoly of jurisdiction of the CJEU, advancing a concept of autonomy of the EU as a claim for power and critiquing the legitimacy and coherence of its foundations. Both dimensions will hopefully help to provide some clarity over the meaning of autonomy and the monopoly of jurisdiction, while, at the same time, promoting a larger discussion on its impact on the external action of the EU.


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