Coastal oil spill predictions for port’s Offensive Security Certified Professional (OSCP) qualification

The Port of Limassol is a critical hub for maritime transport and economic activities in Cyprus, and is prone to oil pollution incidents. The port is designated as a refuge for ships in need of assistance, and shelters a myriad of socio-economic resources. In alignment with international agreements and best practices, oil spill simulations are conducted addressing preventive measures and preparedness.

Several potential oil spill scenarios are considered for the Limassol Port Offensive Security Certified Professional (OSCP) qualification. They include small-to-medium volume releases caused by operational activities within the port and/or at anchorage and the vessel lanes at the Limassol Bay. The port calls include container ships, general cargo vessels, passenger and pleasure craft, navy vessels, dry docks, offshore supply vessels related to oil/gas platforms, drill ships, tankers, and vehicle carriers. Given the port traffic and diversity of vessel types three oil spill scenarios are identified within the three tier levels of potential oil spills and three additional specific scenarios were requested to be simulated as part of the Limassol port OSCP. The identified possibilities for oil spill releases due to marine traffic incidents are noted to be possible and not probable. Therefore, six oil spill scenarios were computed for oil spill simulation: 1) during offloading operations within the port, 2) ship collision outside the port’s gate, 3) outside the port from a drifting vessel, 4) ship-to-ship cargo transfers, 5) vessel grounding, and 6) small fishing vessel sinking.

Results of the oil spill simulations from the six scenarios are based on the 96 simulations using the well-established MEDSLIK model for winter (January and February) and summer (July) in 2017 and 2018. Each oil spill simulation spanned 3-4 days, manifesting once per each period. Daily hydrodynamical data of the CYCOFOS forecasting domain downscaled from the Copernicus Marine Service were used, together with the hourly SKIRON winds in the Eastern Mediterranean. Mostly, more than 50% of the initial spillage reached the shoreline of Limassol Bay. The shorter first impact on the beach was less than 24 hours, followed by gradually coastal depositions accompanied by sporadic oil washing off. For the internal oil spill sources, the impact to the port breakwaters is predicted to be at the very beginning of the leakage. Mainly, 35-47% of oil evaporated within less than 20 hours, while for the emulsified engine oil the evaporation reached 55-60%. The simulations indicate that the extent of the impacted shoreline of the Limassol Bay during winter typically exceeded the summer’s extent. In the winter, the oil spills chiefly were predicted to affect the Limassol port and, secondly, the touristic shoreline of the Limassol Bay. Conversely, in the summer, heavier oil depositions are predicted on the touristic shoreline. Nevertheless, insignificant oil depositions are predicted at the entire sea front of Limassol Bay. The simulations revealed that the numerous wave breakers located along the touristic shoreline of the Limassol Bay serve as “artificial booms” and therefore are mostly coated by the spilled oil, preventing the nearby tourist beaches from direct contamination.