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Accurate simulation of boundary layer surface meteorological parameters is essential to achieve good forecasting of weather and atmospheric dispersion. This paper is devoted to a model sensitivity study over a coastal hyper-arid region in the western desert of the United Arab Emirates. This region hosts the Barakah Nuclear Power Plant (BNPP), making it vital to correctly simulate local weather conditions for emergency response in case of an accidental release. We conducted a series of high-resolution WRF model simulations using different combinations of physical schemes for the months January 2019 and June 2019. The simulated results were verified against in-situ meteorological surface measurements available offshore, nearshore, and inland at 12 stations. Several statistical metrics were calculated to rank the performance of the different simulations and a near-to-optimal set of physics options that enhance the performance of a WRF model over different locations in this region has been selected. Additionally, we found that the WRF model performed better in inland locations compared to offshore or nearshore locations, suggesting the important role of dynamical SSTs in mesoscale models. Moreover, morning periods were better simulated than evening ones. The impact of nudging towards station observations resulted in an overall reduction in model errors by 5–15%, which was more marked at offshore and nearshore locations. The sensitivity to grid cell resolution indicated that a spatial resolution of 1 km led to better performance compared to coarser spatial resolutions, highlighting the advantage of high-resolution simulations in which the mesoscale coastal circulation is better resolved. [ABSTRACT FROM AUTHOR]

The impact of 26 December 2019 annular solar eclipse (ASE) on meteorological conditions over the southeastern Arabian Peninsula is investigated. Observations sourced from the spinning enhanced visible and infrared imager (SEVIRI) and vertical temperature profiles measured by a microwave radiometer were used. The ASE, which began at 03:36:37.9 Universal Time Coordinated (UTC), that is, 31 m 29.9 s after sunrise, left a significant imprint on the land surface temperature (LST). In particular, in some regions, the LST dropped by more than 4 °C, in comparison to the previous day. In situ soil properties, in particular soil texture, were also found to have modulated the effects of the ASE, with loamy soils experiencing higher heating/cooling rates than sandy soils. Finally, the analysis of atmospheric profiles indicated that the eclipse influenced the flow throughout the atmospheric boundary layer, with a stable layer that was 45-min longer and 90-m deeper compared with the preceding day. [ABSTRACT FROM AUTHOR]

This study provides insights on the composition and variability of atmospheric aerosols over the United Arab Emirates (UAE) by analyzing the atmospheric conditions together with 14 years (2006–2019) of aerosol optical depth (AOD) retrieved from CALIPSO (Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite, and 7 years of AOD measured from the ground‐based Aerosol Robotic Network (AERONET). We found that mineral dust is the most prevailing aerosol subtype. In addition, polluted dust and polluted continental aerosols are observed mostly in the cold season. The AOD is higher in spring and summer, when the atmospheric conditions are more favorable to the occurrence of dust events. Moreover, there is another peak in winter associated with dust storms triggered by mid‐latitude baroclinic systems. In summer's daytime, extinction coefficients in excess of 0.2 km−1 are observed up to 3–4 km above the surface, as a result of the warmer and windier conditions. In the cold season and at night, the dust layers are confined to the lower atmosphere below 2 km. On a climatological time scale, we found that the AOD over the UAE has been decreasing since 2009, possibly due to the increasing trend in precipitation and changes in land use. This study highlights the large contribution of dust aerosols to the total aerosol load over the UAE and stresses on the need to account for mineral dust aerosols in climate‐air pollution related studies as well as weather and air quality forecasts. Key Points: Over the UAE, dust is the prevailing aerosol subtype, polluted dust and polluted continental aerosols are also observed mostly in winterIn summer, aerosols are observed up to 3–4 km above the surface, due to a deeper boundary layer. In winter they are confined below 2 kmAOD is higher in spring and summer and it has been decreasing since 2009 in correlation with positive precipitation trends [ABSTRACT FROM AUTHOR]

The results of the development of the model of the antagonistic agents behavior in a cyber conflict are presented. It is shown that the resulting model can be used to analyze investment processes in security systems, taking into account the assumption that investment processes are significantly influenced by the behavior of parties involved in a cyber conflict.General approaches to model development are presented. First of all, the system of concepts, assumptions and limitations is formed, within the framework of which a mathematical model of behavior must be developed. Taking this into account, the mathematical model of the conflicting agents behavior, presented in the form of algebraic and differential equations, is developed. The developed model presents both the technical characteristics of the security system and the psychological characteristics of the participants in the cyber conflict, which affect the financial characteristics of the investment processes in cybersecurity systems. A distinctive feature of the proposed model is the simultaneous consideration of the behavior of the parties to a cyber conflict not as independent parties, but as agents mutually interacting with each other. The model also makes it possible to simulate the destabilizing effect of the confrontation environment disturbances on the behavior of the conflicting parties, changing the degree of vulnerability of the cybersecurity system along various attack vectors and the level of their success. Using the developed model, simulation modeling of the interacting agents behavior in a cyber conflict is performed. The simulation results showed that even the simplest behavior strategies of the attacking side (“the weakest link”) and the defense side (“wait and see”) make it possible to ensure information security of the business process loop. The developed model of interaction between the attacker and the defender can be considered as a tool for modeling the processes of the conflicting parties behavior when implementing various investment scenarios. The simulation results enable decision-makers to receive support regarding the direction of investment in the security of the business process loop. [ABSTRACT FROM AUTHOR]

On 7 March 2014, a Boeing 777-200ER aircraft operated by Malaysian Airlines as MH370 on the route from Kuala Lumpur to Beijing abruptly ceased all communications and disappeared with 239 people aboard, leaving its fate a mystery. The subsequent analysis of so-called satellite "handshakes" supplemented by military radar tracking has suggested that the aircraft ended up in the southern Indian Ocean. The eventual recovery of a number of fragments washed ashore in several countries has confirmed its crash. A number of drift studies were undertaken to assist in locating the crash site, mostly focusing either on the spatial distribution of the debris washed ashore or on the efficacy of the aerial search operation. A recent biochemical analysis of the barnacles attached to the flaperon (the first fragment found in La Réunion) has indicated that their growth likely began in water of 24 °C; then the temperature dropped to 18 °C, and then it rose up again to 25 °C. An attempt was made in the present study to take into consideration all these aspects. The analysis was conducted by means of numerical screening of 40 hypothetical locations of the crash site along the so-called seventh arc. Obtained results indicate the likelihood of the crash site to be located between 25.5 and 30.5° S, with the segment from 28 to 30° S being the most promising. [ABSTRACT FROM AUTHOR]

On March 7, 2014, a Boeing 777-200ER aircraft operated by Malaysian Airlines on the route MH370 from Kuala Lumpur to Beijin abruptly ceased all communications and disappeared with 239 people aboard, leaving a mystery about its fate. The subsequent analysis of so-called satellite "handshakes" supplemented by military radar tracking has suggested that the aircraft ended up in the southern Indian Ocean. Eventual recovery of a number of fragments washed ashore in several countries has confirmed its crash. A number of drift studies were undertaken to assist in locating the crash site, mostly focusing either on the spatial distribution of the washed ashore debris or efficacy of the aerial search operation. A recent biochemical analysis of the barnacles attached to the flaperon (the first fragment found in La Réunion) has indicated that their growth likely began in the water of 24°C, then the temperature dropped to 18°C, and then it rose up again to 25°C. An attempt was made in the present study to take into consideration all these aspects. The analysis was conducted by the means of numerical screening of 40 hypothetical locations of the crash site along the so-called 7th arc. Obtained results indicate the likelihood of the crash site to be located between 25.5°S and 30.5°S latitudes, with the segment from 28°S to 30°S being the most promising. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a comparatively simple technique based on overlapping domain decomposition for the transformation of serial computational algorithms of ocean circulation models into parallel ones. The advantage of the proposed technique is that only additional procedures using basic MPI functionality are required instead of a significant transformation of serial code. The method is fairly efficient for computations on comparatively inexpensive clusters, which are usually affordable for small companies. The impacts of various factors, which may affect the method efficiency are studied. [Copyright &y& Elsevier]