scholarly journals Evaluating the improvements of the BOLAM model of the ISPRA Sistema Idro-Meteo-Mare on the December 2008 flood event in Rome

2010 ◽  
Vol 25 ◽  
pp. 135-141 ◽  
Author(s):  
M. Casaioli ◽  
B. Lastoria ◽  
S. Mariani ◽  
M. Bussettini

Abstract. The Sistema Idro-Meteo-Mare is an integrated meteo-marine forecasting chain for the Mediterranean basin. The recent update of the meteorological segment, based on the hydrostatic BOlogna Limited Area Model (BOLAM), gives the opportunity for a comparative verification study on a Mediterranean cyclone. The 10–12 December 2008 flood event in Rome has been chosen as case study. This disastrous event was claimed to be an extreme one by mass-media; however, its return time is shown here to be about 5 years. The Mediterranean cyclone responsible for the flood offers a tough case study in order to verify the model's ability in reproducing the evolution of meso-synoptic features in the Mediterranean environment. A qualitative comparison, employing satellite data and derived products, is performed. Results suggest that the upgraded model provides a more realistic representation of the cyclone warm sector – where the main rainfall peak took place – whereas the error in the cyclone trajectory and shape evolution is less affected by the BOLAM improvement.

2019 ◽  
Vol 12 (4) ◽  
pp. 141-155 ◽  
Author(s):  
Ahmed Mahdi

This article examines the claim that Israel’s natural gas exports from its Mediterranean gas fields will give geopolitical leverage to Tel Aviv over the importing countries. Using the geoeconomic tradition of Klaus Knorr and others who wrote about applying leverage using economic resources to gain geopolitical advantage, it is argued that certain criteria have to be satisfied for economic influence attempts, and that Israel’s gas exports do not satisfy these criteria. They include the importer’s supply vulnerability, the supplier’s demand vulnerability, and the salience of energy as an issue between both countries. Israeli gas exports to Egypt are used as a case study.


Author(s):  
Peter Behnstedt ◽  
Manfred Woidich

This chapter deals with the sedentary dialects of Egypt, excluding the bedouin dialects of Sinai and the Libyan bedouin dialects on the Mediterranean coast. It attempts to combine historical information on the settlement of Arabic tribes in Egypt with accounts of present-day Egyptian dialects and those of the regions from which those tribes came, initially Yemen and the Levant, later Hejaz, and then the Maghreb. The diversity of the Egyptian Arabic dialect area is partly explained by external factors, namely different layers of arabization over centuries. It is also explained by internal factors, namely dialect contact, which implies phenomena such as hyperdialectisms. Egypt is seen as a dialect area in its own right, but one that shows phenomena of a transitional area between the Arab East and West. A case study of Alexandria deals with dialect death. The role of substrata is discussed, but is considered negligible.


2021 ◽  
Vol 56 ◽  
pp. 102086
Author(s):  
Ismail Haltas ◽  
Enes Yildirim ◽  
Fatih Oztas ◽  
Ibrahim Demir
Keyword(s):  

Author(s):  
Kevin Lesniak ◽  
Conrad S. Tucker

The method presented in this work reduces the frequency of virtual objects incorrectly occluding real-world objects in Augmented Reality (AR) applications. Current AR rendering methods cannot properly represent occlusion between real and virtual objects because the objects are not represented in a common coordinate system. These occlusion errors can lead users to have an incorrect perception of the environment around them when using an AR application, namely not knowing a real-world object is present due to a virtual object incorrectly occluding it and incorrect perception of depth or distance by the user due to incorrect occlusions. The authors of this paper present a method that brings both real-world and virtual objects into a common coordinate system so that distant virtual objects do not obscure nearby real-world objects in an AR application. This method captures and processes RGB-D data in real-time, allowing the method to be used in a variety of environments and scenarios. A case study shows the effectiveness and usability of the proposed method to correctly occlude real-world and virtual objects and provide a more realistic representation of the combined real and virtual environments in an AR application. The results of the case study show that the proposed method can detect at least 20 real-world objects with potential to be incorrectly occluded while processing and fixing occlusion errors at least 5 times per second.


Időjárás ◽  
2021 ◽  
Vol 125 (4) ◽  
pp. 571-607
Author(s):  
André Simon ◽  
Martin Belluš ◽  
Katarína Čatlošová ◽  
Mária Derková ◽  
Martin Dian ◽  
...  

The paper presented is dedicated to the evaluation of the influence of various improvements to the numerical weather prediction (NWP) systems exploited at the Slovak Hydrometeorological Institute (SHMÚ). The impact was illustrated in a case study with multicell thunderstorms and the results were confronted with the reference analyses from the INCA nowcasting system, regional radar reflectivity data, and METEOSAT satellite imagery. The convective cells evolution was diagnosed in non-hydrostatic dynamics experiments to study weak mesoscale vortices and updrafts. The growth of simulated clouds and evolution of the temperature at their top were compared with the brightness temperature analyzed from satellite imagery. The results obtained indicated the potential for modeling and diagnostics of small-scale structures within the convective cloudiness, which could be related to severe weather. Furthermore, the non-hydrostatic dynamics experiments related to the stability and performance improvement of the time scheme led to the formulation of a new approach to linear operator definition for semi-implicit scheme (in text referred as NHHY). We demonstrate that the execution efficiency has improved by more than 20%. The exploitation of several high resolution measurement types in data assimilation contributed to more precise position of predicted patterns and precipitation representation in the case study. The non-hydrostatic dynamics provided more detailed structures. On the other hand, the potential of a single deterministic forecast of prefrontal heavy precipitation was not as high as provided by the ensemble system. The prediction of a regional ensemble system A-LAEF (ALARO Limited Area Ensemble Forecast) enhanced the localization of precipitation patterns. Though, this was rather due to the simulation of uncertainty in the initial conditions and also because of the stochastic perturbation of physics tendencies. The various physical parameterization setups of A-LAEF members did not exhibit a systematic effect on precipitation forecast in the evaluated case. Moreover, the ensemble system allowed an estimation of uncertainty in a rapidly developing severe weather case, which was high even at very short range.


2001 ◽  
Vol 21 (11-12) ◽  
pp. 1121-1137 ◽  
Author(s):  
Christopher E. Naimie ◽  
Daniel R. Lynch
Keyword(s):  

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