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Hanauma Bay is a 101-acre bay created by the partial collapse of a volcanic cone and once supported a vibrant coral reef system. It is the most popular swimming area in the Hawaiian Islands and has been reported to have averaged between 2.8 and 3.5 million visitors a year between the 1980s and the 2010s, with visitors averaging between 3000-4000 a day and peaking around 10,000-13,000 per day. Concentrations of oxybenzone and other common UV filters were measured in subsurface water samples and in sands from the beach-shower areas in Hanauma Bay. Results demonstrate that beach showers also can be a source of sunscreen environmental contamination. Hydrodynamic modeling indicates that oxybenzone contamination within Hanauma Bay's waters could be retained between 14 and 50 h from a single release event period. Focusing on only oxybenzone, two different Hazard and Risk Assessment analyses were conducted to determine the danger of oxybenzone to Hanauma Bay's coral reef system. Results indicate that oxybenzone contamination poses a significant threat to the wildlife of Hanauma Bay. To recover Hanauma Bay's natural resources to a healthy condition and to satisfactorily conserve its coral reef and sea grass habitats, effective tourism management policies need to be implemented that mitigate the threat of sunscreen pollution., Water and beach sand samples were collected under permit and permission from both the City and County of Honolulu's Department of Parks and Recreation and State of Hawaii's Department of Land and Natural Resources. We thank the BIO2MAR platform (http://bio2mar.obs-banyuls.fr) for providing technical support and access to instrumentation. We thank Wendy Wiltse and her associates for assistance in sample collection. We also greatly appreciate and profusely thank the three anonymous reviewers who improved the quality of this manuscript.

Around the world, coral reefs are in decline. Recent interest has focussed on the impacts of global warming/climate change, but the decline started long before the influence of climate change became apparent, driven by anthropogenic factors such as sedimentation, nutrient increase, and overfishing. These continue with no real signs of abatement, as does concomitant reef damage. The Persian Gulf supports widespread coral growth, especially on the Iranian side. Responding to issues of food security, the Iranian government has proposed large-scale aquaculture (open-net fish pens) along their coastline, with an eventual production of 200,000 t/year. Nutrient discharge will be a major issue. We developed a hydrodynamic circulation model for the Persian Gulf which allows us to follow the path of dissolved material. We estimated the amount of nitrogen that would be produced by the projected farms and modelled nitrogen distribution over time, using production rates of 44kgN released/t of fish. In a model run simulating one year at full operation of the proposed number of fish farms, we estimate that most of the reefs on the Iranian side will be bathed in waters with nutrient levels higher than will allow for reef survival. We used a trigger value of 20 μg/l total N. Mangroves will also be affected. There is significant trans-border movement of nutrients, to the waters of neighbouring countries. In fact, withing a few years the entire Gulf will be affected. These planned aquaculture projects have the potential to damage the mangroves and kill every reef in the Persian Gulf in a very short period of time. There is a high probability of affecting fisheries resources in neighbouring countries-a situation to be avoided in politically volatile regions. There seem only two solutions: 1. either run the fish farms so that nutrient discharge is kept to acceptable levels, using an ironclad monitoring system, or 2. bring the operations on land by establishing recirculating aquaculture systems.

Haghshenas, S. A.; Ghader, S.; Yazgi, D.; Delkhosh, E.; Rashedi Birgani.; Razavi Arab, A.; N., Hajisalimi, Z., Nemati, M. H.; Soltanpour, M., and Jedari Attari, M., 2018. Iranian Seas Waters Forecast - Part I: An Improved Model for The Persian Gulf.. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1216–1220. Coconut Creek (Florida), ISSN 0749-0208. The present study aims to improve the accuracy of forecasted wind and wave data generated by a wind-wave forcasting system over the entire Persian Gulf and Strait of Hormuz. A forecasting system has been developed and calibrated for winds and waves in the study area based on available observations. The performance of the developed forecasting system is favorably in agreement with the measured data; however, the model has deficiencies in capturing extreme events in certain situations. Hence, the simulated wi...

Ghader, S.; Yazgi, D.; Haghshenas, S.A.; Razavi Arab, A., Jedari Attari, M., Bakhtiari, A., Zinsazboroujerdi, H., 2016. Hindcasting Tropical Storm Events in the Oman Sea. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1087 - 1091 Coconut Creek (Florida), ISSN 0749-0208. Reliable coastal structure design, sediment transport predictions and future planning all depend on the use of accurate long-term wave data. The present study aims to reproduce measured data from the most important tropical storms in the Oman Sea whose observational data are available. This is assumed as a part of a new wave/wind hindcast for a period of about 30 years over Iranian waters of the Oman Sea. In order to provide a reliable assessment of the wave conditions for this area, three tropical cyclone events are selected for the hindcast model, including Gonu (2007),...

The effect of a thin fluid mud layer on nearshore two-dimensional wave transformation is studied through numerical modeling and wave basin experiments. The wave basin experiments were conducted on both muddy and fixed beds. A mixture of commercial kaolinite and tap water was used as fluid mud layer, where its rheological viscoelastic parameters were derived from rheometer cyclic tests. The results can be utilized for better understanding of the complex wave transformation phenomena under real field conditions where the combined effects of shoaling, refraction, and diffraction as well as wave energy dissipation due to existing mud beds and wave breaking jointly occur. A dissipation model was coupled to the combined refraction and diffraction 1 (REF/DIF 1) wave model to develop a numerical wave height transformation model for muddy beaches. The proposed model was utilized to analyze the experimental data on muddy beds. Comparing the computed values of wave heights over mud layer with the corresponding measurements shows a fair agreement.

A numerical cross-shore model to simulate two features of wave-mud interaction on fine-grained shore profiles, i.e. fluidization of mud layer and wave height attenuation, is presented. The analytical model of Foda et al. (1993) is used to determine the fluidized depth of mud layer. The wave height transformation is computed from the energy flux conservation law combining the effects of mud bed, shoaling and wave breaking. The rheological constitutive equations of visco-elastic (VE) material are used for numerical simulation of fluid mud behavior. A preliminary application of the model shows its capability to predict wave height transformation along soft muddy profiles.

This paper presents an application of Sediment Constituent Analysis (SCA) method to sediment samples taken particularly from the Naiband Bay, the Persian Gulf, to assess current conditions of the coral ecosystem in this area which has been affected by the ongoing developments in the neighboring South Pars Oil Field as well as construction a new port at Haleh in the south east corner of the bay.

Although a variety of cross-shore wave transformation models have been developed during recent decades, there is a lack of suitable models that can be applied to soft mud beds offshore. To address this issue, an integrated cross-shore model is introduced. This model combines the effects of wave shoaling, energy dissipation within fluid mud, and wave breaking. The constitutive equations for a viscoelastic model are adopted for the rheological behavior of fluid mud, whereas stationary mud below fluid mud is assumed to be elastic. As part of the integrated model, submodels for mud fluidization and wave transformation are developed for regular waves and then extended to irregular waves. Application of the integrated model at selected sites using available data reveals that it can reasonably predict mud fluidization and associated wave height transformation.

The present paper offers a set of wave basin experiments on muddy beds together with field measurements data at Hendijan Mud Coast in the north-west corner of the Persian Gulf in order to investigate the 2DH spectral wave transformation over muddy beds. A dissipation model was added to REF/DIF S wave model to develop a numerical wave spectrum transformation model for muddy beaches. The proposed model was utilized to analyze the experimental and field measurements data on muddy beds. The simulated wave spectra over-mud bed are in fair agreement with the measurements.