The second-largest oil pollution incident in the Eastern Mediterranean Levantine basin, following the oil pollution crisis in Lebanon in 2006, is considered to be the oil leakage from the Syrian Baniyas power plant (summer 2021), during which 12,000 tons of oil were released. At the operational phase, the everyday predictions of oil drift were provided using the MEDSLIK and MEDSLIK-II models in the framework of an agreement between the Mediterranean Operational Network for Global Ocean Observing System (MONGOOS) and the Regional Marine Pollution Emergency Response Centre for the Mediterranean (REMPEC). In this work, we present a novel post-operational comprehensive model-based analysis, conducting a SAR validation in two model outputs: the MEDSLIK and the OpenDrift models. Each simulation is initiated with the operationally acquired EMSA-CSN and ESA SAR images. Moreover, the high-resolution met-ocean fields (CYCOFOS, SKIRON) are used to force the oil drift and transformation in both models. The spill was developed under the calm-wind conditions that prevailed during the incident. We found that the boundary sea currents developed on the periphery of the Lattakia eddies (anticyclonic and cyclonic) were responsible for the fast westward spreading of the oil spill offshore in the NE Levantine, the north-south pathway bifurcation, and re-landing of oil in the extended coastal area of Lattakia. Model outputs were validated against Synthetic-aperture radar (SAR) images with appropriate performance metrics, used for the first time, to assess the capacity of a reliable representation of oil spill drift. The intercomparison between the two oil spill models indicated that both models produce almost similar results, while their validation against the satellite SAR observations illustrates moderate accuracy.

Oil spills in the marine field can have serious consequences for ecosystems, the environment, public health, the economy, and communities. Thus, following the spillage of 12,000 tons of crude oil from the fuel tanks of the Baniyas power plant in summer 2021, daily operational oil spill predictions were carried out to predict the spill transport and fate in the Levantine basin, Eastern Mediterranean, supporting the Regional Marine Pollution Emergency Response Centre for the Mediterranean (REMPEC) and national response agencies. High frequency met-ocean forecasting data from the Copernicus Marine Monitoring Service (CMEMS), the European Centre for Medium-Range Weather Forecasts (ECMWF), and regional models (SKIRON, CYCOFOS) were used, along with satellite-derived SAR data from EMSA-CSN and optical images from ESA to initiate the oil spill models and to determine the evolution, the extent and coverage of the spillages. Two up-to-date and advanced Lagrangian particle-tracking models, OpenDrift and MEDSLIK were used to assess and evaluate the oil spill predictions, generated by the aforementioned models, under a variety of met-ocean forcings and configurations, indicating the significant role of the high-resolution met-ocean data in the evolution of the oil spill trajectory. A number of quantitative metrics were used to evaluate the ability to adequately reproduce the oil spill spreading, by comparing the SAR observed oil spillages against the models results, in more detail.

In the frame of the MONGOOS-REMPEC agreement aiming to provide oil spill predictions in causes of major pollution incidents in the Mediterranean Sea, CMCC, ORION and Orbital EOS provided on a voluntary basis daily oil spill predictions based on satellite remote sensing data, following the large Syrian pollution crisis lasted from 23 August to 12 September 2021. As it was reported by REMPEC a total of 12,000 tons of crude oil was spilled in the NE Levantine Basin, at around 10:00 UTC on the 23 August from the fuel tanks of the Baniyas power station in Syria.The current pollution incident is of the same order of magnitude in terms of the amount of the oil spilled at sea from a similar source type, as the one caused during the Lebanon oil pollution crisis in July 2006. The MEDESS4MS multi-oil spill modeling approach was applied, using the different resolution met-ocean forecasting data and two oil spill models. In the Syrian pollution crisis,met-ocean forecasting data from CMEMS Med MFC and ECMWF, CYCOFOS and SKIRON systems were used, as well as the well established MEDSLIK and MEDSLIK-II oil spill models. Moreover, the 27 satellite-derived SAR and optical images provided by the 7 surveillance satellites were processed in order to initiate the oil spill modeling predictions. After the spillage, the oil was washed up on the Syrian coast at the higher concentration along the southern coast of Latakia. Part of the remained sea surface emulsified oil, which was identified as a thick oil (>0.1 mm) oil, was transferred offshore westward and it was widely spread in the NE Levantine between Syria and Cyprus, threatening the most eastern tip of Cyprus. The fast westward movement of the spill was due to the westward strong sea current generated along the southern and northern periphery of the anticyclone and cyclone eddies, respectively. Further on, the emulsified oil mostly was re-circulated by the anticyclone eddy, where part of the oil was re-landed at the Syrian coast and part of it was beached on the Turkish coast near Samandağ, under the increased southerly wind force. After the 6th September the emulsified thin sheen oil was progressively dispersed under the increase of the wind-wave action. The operational response of the MONGOOS members during the Syrian oil pollution crisis that threatened also the neighboring countries in the NE Levantine, demonstrate a best real practice within the broader context of the operational oceanography developments in the Mediterranean, the usefulness of the down streaming applications to the local and regional response agencies to support their decisions during major oil pollution incidents.

This chapter presents an overview and inter-comparison of the main characteristics of the known well-established oil spill models applied in the Black Sea and the Sea of Azov. Since the development of the MyOcean Black Sea Forecasting Centre and, later on, of the Copernicus Black Sea Monitoring Forecasting Centre (CMEMS Black Sea MFC), several oil spill models have been implemented during preparedness exercises and after oil slicks detected from satellite remote sensing Synthetic Aperture Radar (SAR) data. Particularly, in the framework of pilot projects with the European Maritime Safety Agency CleanSeaNet (EMSA-CSN), 24 h forward and backtracking spill predictions were initiated in near real time using the satellite data provided through EMSA-CSN portal. In addition, several European Commission projects, for example, the European Marine Observation and Data Network (EMODnet) Black Sea Check points addressed issues related to oil leakages in the Black Sea taking advantage of the operational met-ocean forecasting in the region, is summarized in the chapter. Examples of oil spills modelling applications in the Black Sea and the Sea of Azov are presented using met-ocean forecasting data and satellite data. The catastrophic Volgoneft-139 oil spill in the Kerch Strait, in November 2007, is described. Several contemporary well-established oil spill modelling systems, three of them, MEDSLIK, MEDSLIK-II, BlackSeaTrackWeb were applied during emergencies and warnings, while the rest examined modelling systems, GNOME, MOTHY, OILTOX, OILMAP, OSCAR were applied during dedicated risk assessments. All these oil spill modelling systems implemented in the Black Sea and the Sea of Azov were inter-compared in terms of their characteristics concerning the physical/chemical spill processes, number of different oil types, type of oil discharges, initial slick shape, type of slick discharges and areas of oil spill model's applicability.

The Cyprus coastal ocean forecasting system, known as CYCOFOS has been providing operational hydrodynamical and sea state forecasts in the Eastern Mediterranean since early 2002. Recently, it has been improved with the implementation of new hydrodynamic and new wave modeling systems with the objective of targeting higher resolution domains, at coastal, sub-regional and regional scales in the Mediterranean and the Black Sea. For the new CYCOFOS hydrodynamic modeling system a novel parallel version of the well established POM has been implemented. The new CYCOFOS hydrodynamical models covers the entire Eastern Mediterranean with a resolution of 2 km and the Levantine Basin with a resolution of ~600 m, both nested in the Copernicus Marine Environmental Monitoring Service of the Mediterranean Forecasting Center-CMEMS Med MFC. For sea waves forecasting, CYCOFOS has implemented the new ECMWF wave model WAM CY46R1 in the Mediterranean and the Black seas at a higher resolution of 5 km. The CYCOFOS hydrodynamical models received an extended cal/val against the parent model, Argo profiles and satellite SST time series, while in-situ wave data gathered by the HERMES buoy monitoring network in the Eastern Mediterranean and the Black Sea were used for statistical validation of the new CYCOFOS wave forecasts. The new CYCOFOS validated modeling systems, provide higher resolution quality controlled forecasting data suiting the needs for : a) down-streaming applications supporting risk assessment for offshore platforms in the Levantine Basin and studies concerning the coastal erosion in the Eastern Mediterranean (Albania, Cyprus, Greece) and the Black Sea (Bulgaria) in the framework of the HERMES project, and b) further hierarchical downscaling applications for the development of the COASTAL CRETE operation forecasting system at a higher resolution in the Eastern Mediterranean (Crete, Greece).

Two of the major risks from an oil spill incident at sea are associated with the maritime transport and the coastal/offshore installations related to the oil and gas industry exploration and exploitation. Such risks call for preparations of the operational response to oil spill incidents, based on the lessons learned from the sinking of Exxon Valdez in 1989, Haven in 1991, Prestige in 2002, the Lebanon oil pollution crisis in 2006 and BP's Deepwater Horizon offshore drilling platform catastrophe in 2010. There are several international and regional policies, which have been implemented for oil spill response, such as the MARPOL, Barcelona, and Black Sea Commission conventions. The conventions recognize pollution from oil spills as one of the major threats to the marine environment in regional seas, such as the Mediterranean Sea and the Black Sea. At the European Union (EU) level, the Member States were requested to implement various EU Directive concerning the response measurements for oil spill incidents, such as for example the EU 2005/35 aimed at identifying marine pollutes. The response to an oil spill incident requires various measures and engagement of various types of equipment and the success of the response as a whole depends greatly on the prediction of the movement and weathering of the oil spill. Such predictions can be obtained via an operational implementation of well-established numerical oil spill models, integrated with high resolution data, which may be downscaled from global and/or regional metocean forecasts. Numerous oil spill predictions systems were developed to predict the transport, diffusion, and the weathering processes of evaporation, emulsification, viscosity changes, dispersion and coastal impacts and adhesion of oil; only few of them provide predictions/parameterizations of oil plumes released from any given water depth, of biodegradation and the effects of ice. To this end, an overview of the transport and weathering processes incorporated in operational oil spill models is provided in this chapter, together with oil plumes biodegradation, and oil in ice parameterizations. Moreover, examples of best practices to assist the response agencies at regional and local levels in case of oil spillages are provided: the integration of routine satellite monitoring of oil slicks from SAR data with the oil spill models for short operational forward and backward trajectories predictions and harmonized multimodel approach for oil spill predictions, demonstrating the increase of confidence in oil spill modeling prediction, especially during long-term oil spill simulations using hind-cast metocean data to evaluate and assess the impact from potential and/or existing oil pollution sources at monthly, seasonal and interannual scales, to sensitive coastal and offshore infrastructures.

One of the largest last decade discoveries of hydrocarbons in the Eastern Mediterranean Sea is the Leviathan field, which constitutes a large-scale energy program of the State of Israel. Gas and condensate from the Leviathan well are transferred via pipeline to an offshore platform located ~10 km from the Israeli shoreline, and from there via a pipeline to the coastal Leviathan energy installation. The local communities are concerned from the pollution implications that might occur in case of spillage and/or any malfunction in regular operation.The present work includes review of previous environmental studies regarding the Leviathan energy project 2007-2011, new extended simulations 2015-2018 for condensate, diesel and grey water leaks and resultant evaporation simulations caused by possible condensate spillage from the offshore platform and the pipe rupture.In the framework of the current study concerning the Leviathan offshore platform, a robust statistics is obtained by 5844 spill simulation runs for condensate and diesel against12 runs as mentioned in the previous studies, while for the pipe rupture a robust statistics was made with 104 runs for condensate and diesel compared to12 runs as performed previously.The previous spillage scenarios from the offshore platform had underestimated by almost order of magnitude the content per design itself (1000bbls vs. ~6000bbls) and documentation of permits. Similarly, the pipe rupture spillage scenarios underestimated by almost half order of magnitude (1200bbls vs. ~3000bbls). Therefore, the current simulations predicted larger spillage quantities, compared to the aforementioned previous simulations.The main conclusions driven from the 10km counter simulations for the offshore platform spillage show the following: First oil arrival at the Israeli coast from the offshore platform is predicted to be within 8 hours after start of spillage event in winter, and within 11 hours in summer.The first impacted area is predicted to be the coastline between Zichron-Ya'akov/Dor and Atlit. In winter on average, it is predicted that 17% of the spillage is beached, while in summer, twice as higher, i.e. up to 35%. Deposition of spilled condensate in the Hadera desalination plant is estimated to be the highest among the 5 desalination plants examined.Similarly, the main conclusions driven from the 1km pipe rupture spillage counter show that the first impact on the Israel is predicted to be within 5-6 hours after start of spillage in winter, and within 3-4 hours in summer, with the worst case scenario occurring within half an hour after start of the spillage. The coastline of Zichron-Ya'akov is found to be an epicenter of the highest condensate deposition up to 15 tons/km, regardless the season. Due to the proximity of the pipe rupture to the shore, it is predicted that 38-40% of the condensate washed up the shore nearby, without any significant seasonal or monthly variability. The condensate spillage from the pipe rupture located 1 km from the shoreline will affect mostly the Atlit, Ma'agan-Michael and Caesarea National parks’ and the Hadera desalination plant coastlines.

An oil plume model to simulate the behavior of oil from spills located at any given depth below the sea surface is presented, following major modifications to a plume model developed earlier by Malačič (2001) and drawing on ideas in a paper by Yapa and Zheng (1997). The paper presents improvements in those models and numerical testing of the various parameters in the plume model. The plume model described in this paper is one of the numerous modules of the well-established MEDSLIK oil spill model. The deep blowout scenario of the MEDEXPOL 2013 oil spill modelling exercise, organized by REMPEC, has been applied using the improved oil plume module of the MEDSLIK model and inter-comparison with results having the oil spill source at the sea surface are discussed.

Oil spills in the ocean are a matter of concern due to the damaging effect they can have on coastal and offshore resources. This work presents a review of present-day modeling techniques used in the mitigation of oil spills by booms, skimmers, chemical dispersants, and other equipment and the importance of the controlling parameters of these techniques. Three basic questions need to be addressed by oil spill models: (1) where the spill will move, (2) when will the spill get to the modeled endpoints, and (3) what will be its state when it arrives. The first two questions are relatively urgent, as far as response measures are concerned, and depend closely on the use of accurate data on winds, sea currents, and wave action as oil spill accidents evolve. Obtaining a reasonable answer to the third question lies in the use of reliable fate algorithms. Oil spill models can be divided in two types: Euleurian and Langragian. Adding to information regarding the oil type and its initial location, all oil spill models require data for the wind fields, sea state, sea-surface temperature, and currents, as well as other environmental parameters, if available. Such reliable data suit the needs of oil spill modeling predictions and are available daily at global, regional, and coastal scales within the broader scope of operational oceanography. Advanced oil spill models available at present use satellite synthetic aperture radar (SAR) images/data to detect possible oil slicks and assimilate slick and drifter observations to correct slick predictions. The emphasis of research and governmental institutions has been on improving 4D predictions obtained through simulation of oil spills backward in time to track the slicks back to their source. Such backward simulations, when integrated with ships' Automatic Identification Systems (AIS), will be used to locate the sources of oil slicks around the world's oceans and seas.

In the Mediterranean sea the risk from oil spill pollution is high due to the heavy traffic of merchant vessels for transporting oil and gas, especially after the recent enlargement of the Suez canal and to the increasing coastal and offshore installations related to the oil industry in general. The basic response to major oil spills includes different measures and equipment. However, in order to strengthen the maritime safety related to oil spill pollution in the Mediterranean and to assist the response agencies, a multi-model oil spill prediction service has been set up, known as MEDESS-4MS (Mediterranean Decision Support System for Marine Safety). The concept behind the MEDESS-4MS service is the integration of the existing national ocean forecasting systems in the region with the Copernicus Marine Environmental Monitoring Service (CMEMS) and their interconnection, through a dedicated network data repository, facilitating access to all these data and to the data from the oil spill monitoring platforms, including the satellite data ones, with the well established oil spill models in the region. The MEDESS-4MS offer a range of service scenarios, multi-model data access and interactive capabilities to suite the needs of REMPEC (Regional Marine Pollution Emergency Response Centre for the Mediterranean Sea) and EMSA-CSN (European Maritime Safety Agency-CleanseaNet).

This study uses new oil-spill models, bathymetric, meteorological, oceanographic, geomorphological and geological data to assess the impact of distinct oil spill scenarios on the southern coast of Cyprus, Eastern Mediterranean. This approach results from the urgent need to predict oil spill dispersion after new oil terminals and depots were built at Vasilikos, southern coast of Cyprus. The terminals have been able to receive tankers with ~500,000 deadweight tonnes from November 2014. The new geomorphological and geological data in this work show the shoreline of Cyprus to be of high susceptibility due to: (a) the presence of a narrow continental shelf capable of trapping large quantities of hydrocarbons; (b) the existence of uplifted wave-cut platforms, coastal lagoons and pools forming natural traps for oil, and (c) the presence of important tourist and Natura 2000 sites. Under particular weather and oceanographic conditions, oil spills offshore Larnaca Bay will quickly spread and reach the shoreline ~46h after the initial accident. Significantly, the models in this paper show a reduction from 84% to 19% in the volume of oil trapped on the coast if dispersants are applied, with the latter 19% being potentially kept at bay using booms and mechanical removal techniques. Based on these results, we suggest the early use of dispersants, booms and mechanical removal procedures to prevent the spreading of oil spilt in the broad area of Larnaca Bay.

We present new mathematical and geological models to assist civil protection authorities in the mitigation of potential oil spill accidents in the Eastern Mediterranean Sea. Oil spill simulations for 19 existing offshore wells were carried out based on novel and high resolution bathymetric, meteorological, oceanographic, and geomorphological data. The simulations show a trend for east and northeast movement of oil spills into the Levantine Basin, affecting the coastal areas of Israel, Lebanon and Syria. Oil slicks will reach the coast in 1 to 20 days, driven by the action of the winds, currents and waves. By applying a qualitative analysis, seabed morphology is for the first time related to the direction of the oil slick expansion, as it is able to alter the movement of sea currents. Specifically, the direction of the major axis of the oil spills, in most of the cases examined, is oriented according to the prevailing azimuth of bathymetric features. This work suggests that oil spills in the Eastern Mediterranean Sea should be mitigated in the very few hours after their onset, and before wind and currents disperse them. We explain that protocols should be prioritized between neighboring countries to mitigate any oil spills.

Oil spill models are combined with bathymetric, meteorological, oceanographic, and geomorphological data to model a series of oil spill accidents in the Eastern Mediterranean Sea. A total of 104 oil spill simulations, computed for 11 different locations in the Levantine Basin, show that oil slicks will reach the coast of Cyprus in four (4) to seven (7) days in summer conditions. Oil slick trajectories are controlled by prevailing winds and current eddies. Based on these results, we support the use of chemical dispersants in the very few hours after large accidental oil spills. As a corollary, we show shoreline susceptibility to vary depending on: a) differences in coastline morphology and exposure to wave action, b) the existence of uplifted wave-cut platforms, coastal lagoons and pools, and c) the presence of tourist and protected environmental areas. Mitigation work should take into account the relatively high susceptibility of parts of the Eastern Mediterranean.

MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations. The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results.

This paper consists of two parts: in the first part Gulfslik II a mathematical model that simulates surface oil spill transport is tested using the drifting buoys data of the Mt Mitchell cruise. In the second part an empirical formula based on the drift factor approach to estimate surface oil spill transport due to wind is derived.