Numerical modeling of storm surge attenuation by mangroves in protected area of mangroves of Qheshm Island

With the experience of storm surges along Persian Gulf of Iran it is needed to simulate storms in coastal areas and study the protection techniques in order to protect communities and industrial facilities in coastal areas. Mangrove forests play a unique role in attenuating storm surge during tropical cyclones. MIKE21 FM is an applicable software for simulating cyclones within coastal environments. A hydrodynamic model is used to analyze the attenuating role of the protected area of mangroves between Gheshm Island and Khamir Port mangroves under a realistic conditions by updating the calibrated Manning's coefficient based on the land cover data to incorporate the mangrove effect with modifying bottom friction and characteristics of cyclone Gonu 2007 which is the strongest cyclone recorded in the Arabian Sea and Persian Gulf. In this research we measured the maximum surge levels in both scenarios (in situ conditions and the condition which mangrove forest is neglected); maximum storm tide reduction by mangroves (MSTRM) by mangroves and maximum storm tide reduction rate by mangroves (MSTRRM). Also inundation maps are presented aiming to measure the areas rescued from inundation and the areas inundated caused by mangroves. The simulations shows that the minimum and maximum storm tide reduction rate by mangroves are 5.32% and 34.88% respectively.