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The Mediterranean, and particularly its Eastern basin, is a crossroad of air masses advected from Europe, Asia and Africa. Anthropogenic emissions from its megacities meet over the Eastern Mediterranean, with natural emissions from the Saharan and Middle East deserts, smoke from frequent forest fires, background marine and pollen particles emitted from ocean and vegetation, respectively. This mixture of natural aerosols and gaseous precursors (Short-Lived Climate Forcers—SLCFs in IPCC has short atmospheric residence times but strongly affects radiation and cloud formation, contributing the largest uncertainty to estimates and interpretations of the changing cloud and precipitation patterns across the basin. The SLCFs' global forcing is comparable in magnitude to that of the long-lived greenhouse gases; however, the local forcing by SLCFs can far exceed those of the long-lived gases, according to the Intergovernmental Panel on Climate Change (IPCC). Monitoring the spatiotemporal distribution of SLCFs using remote sensing techniques is important for understanding their properties along with aging processes and impacts on radiation, clouds, weather and climate. This article reviews the current state of scientific know-how on the properties and trends of SLCFs in the Eastern Mediterranean along with their regional interactions and impacts, depicted by ground- and space-based remote sensing techniques. [ABSTRACT FROM AUTHOR]

Tropical Cyclone Shaheen (TCS), originating in the Arabian Sea on 30 September 2021, followed an east-to-west trajectory and made landfall as a category-1 cyclone in northern Oman on 3 October 2021, causing severe floods and damages before dissipating in the United Arab Emirates. This study aims to analyze the synoptic and dynamical conditions influencing Shaheen's genesis and evolution. Utilizing ERA5 reanalysis data, SEVIRI-EUMETSAT imagery, and Sorbonne University Atmospheric Forecasting System (SUAFS) outputs, it was found that Shaheen manifested as a warm-core cyclone with moderate vertical wind shear within the eyewall. Distinctive features included a trajectory aligned with rising sea surface temperatures and increased specific humidity levels at 700 hPa in the Arabian Sea. As Shaheen approached the Gulf of Oman, a significant increase in rainfall rates occurred, correlated with variations in sea surface temperatures and vertical wind shear. Comparative analysis between SUAFS and ERA5 data revealed a slight northward shift in the SUAFS track and landfall. Advance warnings highlighted heavy rainfall, rough seas, and strong winds. This study provides valuable insights into the meteorological factors contributing to Shaheen's formation and impact. [ABSTRACT FROM AUTHOR]

Wildfires are an escalating global threat, jeopardizing ecosystems and human activities. Among the repercussions in the ecosystem services of burnt areas, there are altered hydrological processes, which increase the risks of flash floods. There is limited research addressing this issue in a comprehensive way, considering pre- and post-fire conditions to accurately represent flood events. To address this gap, we present a novel approach combining multiple methods and tools for an accurate representation of post-fire floods. The 2019 post-fire flood in Kineta, Central Greece is used as a study example to present our framework. We simulated the meteorological conditions that caused this flood using the atmospheric model WRF-ARW. The burn extent and severity and the flood extent were assessed through remote sensing techniques. The 2D HEC-RAS hydraulic–hydrodynamic model was then applied to represent the flood event, using the rain-on-grid technique. The findings underscore the influence of wildfires on flooding dynamics, highlighting the need for proactive measures to address the increasing risks. The integrated multidisciplinary approach used offers an improved understanding on post-fire flood responses, and also establishes a robust framework, transferable to other similar cases, contributing thus to enhanced flood protection actions in the face of escalating fire-related disasters. [ABSTRACT FROM AUTHOR]

This paper deals with a two-echelon supply chain comprising a retailer and manufacturer. The retailer faces Poisson demand and follows a ( S, s) continuous review inventory policy. The manufacturer produces and ships the retailer's orders with random delay that follows the Coxian-2 distribution. Assuming lost sales at the retailer and infinite capacity at the manufacturer, we try to explore the performance of the supply chain system. The system is modeled as a continuous-time Markov process with discrete space. The structure of the transition matrices of these specific systems is categorized as block-partitioned, and a computational algorithm generates the matrices for different values of system characteristics. The proposed algorithm allows the calculation of performance measures-fill rate, cycle times, average inventory (work in progress [WIP])-from the derivation of the steady-state probabilities. Moreover, expressions for the holding costs and shortage costs are derived. [ABSTRACT FROM AUTHOR]

• The fingerprint of an intense medicane is examined over the central-eastern Mediterranean Sea. • This analysis is made possible due to the expansion of the Argo network in the marginal seas. • The medicane affected the upper-layer hydrography, the water masses structure, the heat content, and the mixed-layer depth. • Thermohaline alterations are highlighted in surface and subsurface layers. • Such information can be particularly important for fisheries, aquaculture, and coupled met-ocean forecasts. The formation of cyclones over the sea surface is driven by air-sea interaction with feedbacks on wave generation, thermohaline structures, and biochemical properties of upper-ocean layers. In the Mediterranean basin, strong cyclonic systems having tropical-like characteristics are called "medicanes". The consequences of such events are usually assessed over the land, however, hydrographic effects are particularly difficult to be quantified mostly due to the rarity of oceanographic in-situ monitoring systems. In this study, the hydrographic effects of a high-impact medicane, crossing the central-eastern Mediterranean in late September 2018 are investigated mainly based on Argo float measurements. We traced its hydrographic fingerprint and examined its effects on the upper-layer physical properties by analyzing temperature and salinity profiles from floats that overlapped with its track. Float data is supported by satellite sea surface temperature reanalysis data and meteorological records. The synergistic effects of intense evaporation and vertical mixing mechanisms triggered by the medicane, resulted in abrupt surface cooling, especially in the Ionian and Aegean Seas. A relatively homogenous decrease of temperature in the upper 50-m-depth layer followed, along with the deepening of the mixed-layer depth, corresponding to an estimated per profile average deficit of (-2.72 ± 1.23) x 108 J m−2 in the ocean heat content. Simultaneously, significant upper-layer freshening occurred because of vertical mixing and heavy rainfall. However, a salinity increase in the subsurface waters was observed after the medicane event, which is associated with both horizontal advection and vertical mixing which followed the weakening of the Atlantic Water signal and the dominance of the Levantine Surface Water in this zone. Our findings highlight strong, short-scale hydrographic alterations made available due to the expansion of the marginal seas operational oceanographic network. [ABSTRACT FROM AUTHOR]