Developing a capacity for storm surge forecasting in the Maltese islands

Abstract

The aim of this project is to develop components of a prototype system for the forecasting of sea level variations and extreme mean sea levels in the area of the Maltese Islands. The system makes use of a high resolution coastal numerical model nested to the storm surge operational model run by the Spanish (Nivmar) covering the full Mediterranean Sea. The coastal model makes use of a finite element mesh which allows the resolution to focus with more grid cells on geographical areas of higher interest, thus allowing coastal embayment to be resolved. This work is conducted within a research project at the Physical Oceanography Unit (PO-Unit) in collaboration with international partners. Tasks include the configuration of the coastal model and the formulation and tuning of suitable boundary conditions from the coarse model. The system is implemented to run in pre-operational mode and validated against observations. The validation involves the creation of a beta version of the model where a series of numerical experiments are conducted to validate against observations. The objective is to fine tune the performance of the sea level forecasts. This higher resolution sea level forecasting model is intended to be subsequently linked to the operational forecast system run by the PO-Unit. Storm surges are related to atmospheric disturbances and result in extreme conditions of high mean sea levels which put high risks to inundation and render storm water floods more severe, especially in low lying areas such as Msida and Burmarrad. The work includes conducting statistics on the occurrence of storm surges in Malta. This kind of research is a precursor to applications of storm surge modelling in coastal areas and offers a potential application to other areas in Mediterranean.