Experimental investigation into the usage of date palm forests to mitigate tsunamis in the Middle East

Owing to the rare occurrence of tsunamis in the Arabian Sea, and the lack of reliable records on them, tsunami preparedness has not been prioritized in plans for the development of coastal cities in the Middle East. However, an increase in the number of earthquakes in the region in the recent past has highlighted the vulnerability of low-lying coastal areas to tsunamis. We investigate the potential of date palm forests to mitigate tsunamis in the Middle East. Experiments were conducted at a scale of 1:100 to assess the effectiveness of forests in reducing the intensity of tsunamis. The reflection at the front of the forest was negligibly small when the depth of flow was lower than the height of the canopy, and increased with the height of the tsunami wave when the depth of flow was higher than the height of the canopy. This shows that the structure of the canopy of date palm trees is key to reducing the energy of the tsunami. The reduction in the maximum depth of flow behind the forest increased with the height of the tsunami when the forest was longer than 120 m. The largest reductions obtained in the depth and velocity of flow behind the forest were 37% and 40%, respectively, when the forest was 180 m long and the tsunami wave was 7 m high. The results suggest that a date palm forest with a length of at least 150 m on flat ground can mitigate tsunamis in the Middle East.