Effects of Harbor Shape on the Induced Sedimentation; L-Type Basin

Tsunamis in shallow water zones lead to sea water level rise and fall, strong currents, forces (drag, impact, uplift, etc.), morphological changes (erosion, deposition), dynamic water pressure, as well as resonant oscillations. As a result, ground materials under the tsunami motion move, and scour/erosion/deposition patterns can be observed in the region. Ports and harbors as enclosed basins are the main examples of coastal structures that usually encounter natural hazards with small or huge damaging scales. Morphological changes are one of the important phenomena in the basins under short and long wave attack. Tsunamis as long waves lead to sedimentation in the basins, and therefore, in this study, the relation to the current pattern is noticed to determine sedimentation modes. Accordingly, we present a methodology based on the computation of the instantaneous Rouse number to investigate the tsunami motion and to calculate the respective sedimentation. This study aims to investigate the effects of the incident wave period on an L-type harbor sedimentation with a flat bathymetry using a numerical tool, NAMI DANCE, which solves non-linear shallow water equations. The results showed that the corner points on the bending part of the basin are always the critical points where water surface elevation and current velocity amplify in the exterior and interior corners, respectively

Lessons Learned from the 2011 Great East Japan Tsunami: Performance of Tsunami Countermeasures, Coastal Buildings, and Tsunami Evacuation in Japan

In 2011, Japan was hit by a tsunami that was generated by the greatest earthquake in its history. The first tsunami warning was announced 3 min after the earthquake, as is normal, but failed to estimate the actual tsunami height. Most of the structural countermeasures were not designed for the huge tsunami that was generated by the magnitude M = 9.0 earthquake; as a result, many were destroyed and did not stop the tsunami. These structures included breakwaters, seawalls, water gates, and control forests. In this paper we discuss the performance of these countermeasures, and the mechanisms by which they were damaged; we also discuss damage to residential houses, commercial and public buildings, and evacuation buildings. Some topics regarding tsunami awareness and mitigation are discussed. The failures of structural defenses are a reminder that structural (hard) measures alone were not sufficient to protect people and buildings from a major disaster such as this. These defenses might be able to reduce the impact but should be designed so that they can survive even if the tsunami flows over them. Coastal residents should also understand the function and limit of the hard measures. For this purpose, non-structural (soft) measures, for example experience and awareness, are very important for promoting rapid evacuation in the event of a tsunami. An adequate communication system for tsunami warning messages and more evacuation shelters with evacuation routes in good condition might support a safe evacuation process. The combination of both hard and soft measures is very important for reducing the loss caused by a major tsunami. This tsunami has taught us that natural disasters can occur repeatedly and that their scale is sometimes larger than expected

THE 25 MARCH 2020 TSUNAMI AT THE KURIL ISLANDS: ANALYSIS AND NUMERICAL SIMULATION

A strong earthquake with a magnitude of 7.5 occurred near the island of Paramushir (KurilIslands) on 25 March 2020. It caused a weak tsunami in Kamchatka and the Kuril Islands.Earthquake and tsunami data from three DART buoys are discussed and compared withnumerical simulations. It is shown that the calculated and measured tsunami characteristics onthe DART buoys is in very good agreement. There are also data on the recording of thisearthquake by a laser strain-meter installed in the Sea of Japan at Shults cape at a distance ofmore than 2,000 km from the epicenter of the earthquake. There is also an instrumentalrecording of the tsunami at the Vodopadnaya point in the southeast of Kamchatka.Unfortunately, there was a large storm at sea at this time, and the amplitudes of tsunami wavesand storm waves were comparable to each other, so here the agreement between calculationsand observations does not seem good enough

Kıyılarda iklim değişikliğine karşı kumlanma modeli destekli kırılganlık analiz projesi-KIDEKA

TÜBİTAK MAG15.03.201

Karadeniz ve Akdeniz tsunamileri için model geliştirme ve risk analizi projesi

TÜBİTAK ÇAYDAG15.07.201

Deniz Koruma Alanları Uydu Görüntü Destekli Kirlenme İzleme Ve Taşıma Kapasitesi Araştırma Projesi

Deniz turizminin yoğun olduğu bölgelerde deniz araçları kullanımı yoğun olmakta ve kirlenme boyutları limitleri aşmaktadır. Bunun önlenmesi için koylarda yat taşıma kapasitesinin ulaşabileceği sınır değerlerinin ortaya çıkarılması ve sağlıklı uygulanabilir önlemler geliştirilmesi önemlidir. Bu çalışma ile, Fethiye-Göcek Özel Çevre Koruma Bölgesi Göcek Körfezi ile koylarında, deniz üstü araçları açısından taşıma kapasitesinin belirlenmesi ve alan yönetimine ilişkin kararların alınabilmesi için bilimsel çalışma yapılarak, gerekli veri tabanı oluşturulması ve izleme amaçlı bilgisayar yazılım araçları geliştirilmesi ve öneriler hazırlanması amaçlanmıştır. Önerilen Araştırma Projesi, Fethiye Koyu' nda su çevrimi ve kirlenme özelliklerinin yıllık değişimlerini Coğrafi Bilgi Sistemi tabanlı veriler kullanıp analiz ederek, yerinde ölçümlerle doğrulayıp, yat hareketlerini izlemeyi ve bu verileri kullanarak körfezin yat taşıma kapasitesini saptamayı amaçlamaktadır. Proje kapsamında yüksek çözünürlüklü uydu görüntüleri elde edilmesi, bu görüntülerin yeni gelişmiş özel amaçlı yazılımlar kullanarak analiz edilerek kirletici parametrelerinin çıkarılması, bu parametrelerin saha değerlerinin yerinde ölçümler yapılarak kalibrasyon yapılması, su parametrelerinin ölçümlerle izlenmesi, yat hareketlerinin kamera ile izlenmesi, yatlardan ve karadan gelen kirleticilerin araştırılması ve kirlenme potansiyelinin bulunması ve kıyı Alanları Yönetim planı içinde Özel Çevre Koruma Bölgeleri için Taşıma Kapasitesi hesaplanması için yöntemler geliştirilmesi ve Fethiye Körfezi Yat taşıma kapasitesi saptanması sağlanacaktır

Transmission and reflection of solitary waves from vertical porous structures

Ph.D. - Doctoral Progra

Reflection of solitary waves from porous structures.

Presents experimental data on the characteristics of the reflected wave which forms when a solitary wave meets a vertical porous structure. The wave flume laboratory experiments and results are discussed. Deformation of the reflected wave observed in these experiments was further investigated in computer simulation studies and is described in detail. The major findings of the study were: the reflected wave initially has the same value of the pulse width (phase) parameter as the incoming solitary wave, its profile deforms during its propagation to a single solitary wave of reduced height with a depression tail, and its volume increases during deformation due to transfer of water from the developing depression tail. (J.M.M.

Initial stage of database development for tsunami warning system along Turkish coasts

The highly active seismic potential of Eastern Mediterranean raises a question about risk mitigation when a possible tsunami hits the coastline. A proper risk mitigation plan and tsunami assessment can be achieved by creating a fully detailed database. In this study, 38 scenarios created using this database on bathymetric and topographic data in sufficient resolution using valid and verified numerical tool called NAMI DANCE, helps us to understand the tsunami generation, propagation, coastal inundation aided by visualization. The uncertainties in defining seismic source parameters and the effect of dip and rake (slip) angle are discussed. The performance and efficiency of the numerical code, the accuracy of the results in the application to Eastern Mediterranean Tsunamis and the comparisons of simulation results in nested domains for the towns of Iskenderun and Kas are given as case studies. According to this study, northwest and south-west of Turkey may have tsunami risks more than the other regions. The maximum wave amplitudes that hit the coasts are more than 4 m and about 6 m at some localities. The arrival time of the first wave to hit the coast varies between 15 min to 60 min depending on the proximity to the source location

Overtopping of solitary waves at model sea dikes

This paper discusses an analytical model for solitary wave overtopping at sea dikes. The model is based on the 'weir flow analogy' of Kikkawa et al.(1968). Results of laboratory test on smooth and impermeable model dikes with angles of 45°, 60° and 90° are utilized in constructing the model. Results for solitary waves are compared with those for regular oscillatory waves for the case of vertical dike