Hydrodynamic Modeling of the Gulf of Aqaba

The Gulf of Aqaba (GOA) is unique as it contains significant percentage of the world’s natural marine biodiversity. This unique environment is potentially vulnerable to pollution particularly at its northern tip. One of the major activities affecting the environment of the gulf is the man-made desalination plants that abstract sea water and dispose desalinated brine. In this context, the paper discusses the impact of the abstract and disposal activities on the GOA environment. A 3D hydrodynamic model was developed to cover the GOA. Relevant data were collected for 3D hydrodynamic modeling construction. Delft-3D model developed by Deltares was applied in this study. The 3D model reliability was confirmed since the model results have revealed the existence of a structure of primary eddies along the axis of the Gulf which was previously reported by different researchers. Further numerical simulations were carried out by incorporating various alternatives of seawater abstraction and desalinated brine disposal off the north and north east coast of the GOA. The developed GOA hydrodynamic model, at the present stage, is preliminary where the results provide qualitative assessment on the potential impacts on the water circulation. Accordingly, this study is considered a pace ahead for a better model development and validation in the future studies.

Mesoscale Numerical Study of Quasi-Stationary Convective System over Jeddah in November 2009

25 November 2009 is an unforgettable day for the people in Jeddah, the second largest city in the Kingdom of Saudi Arabia (KSA). On that day, Jeddah turned into a disaster zone following a short heavy rainfall event that triggered flash floods leaving 122 fatalities and considerable losses. Numerical experiments using the Pennsylvania State University-National Center for Atmospheric research mesoscale meteorological model (MM5) have been performed to investigate the event. It was caused by a short quasi-stationary mesoscale convective system that developed over Jeddah and lasted for about 8 hours. Rainfall totals computed by the model exceeded 400 mmin some localities in the southern part of Jeddah city and to the north of Jeddah in Thuwal city. The limited available observed rainfall totals, atKingAbdulAzizInternationalAirportand wadiQaws rain gauges, and Jeddah’s weather radar observations corroborates the ability of the model to reproduce the spatial and temporal characteristics of the rainfall event. A synoptic environment characterized by warmRed Seasurface temperatures and high humidity in the low levels of the troposphere. A stationary anticyclone centered over the southeast of theArabian Peninsulaconcentrated the water vapour flow to a narrow passage over Jeddah. Simulation results suggested that the development of a mesolow by latent heat release, as well as cyclogenesis induced by Al Hejaz escarpments, could have played an important role in enhancing the event by providing low-level convergence and enhanced upslope winds, and upper level atmospheric instability.

Development of Solar Ponds Optimization Model: Arab Potash Solar System—A Case Study

A steady state optimization model used to define the optimum salt to carnallite ponds area ratio in a solar pond system was developed. The model is based on material balance analysis using a cascade of complete-mix reactors model (cascade of CFSTR, continuous-flow stirred-tank reactor) prepared for the solar pond system. The basic material balance model shall use the basic phase chemistry relations and physical parameters of the solar pond system under optimization. The Arab Potash solar pond system data was used to examine the developed model where the Arab potash solar system was used as a Case Study. In the course of the model development, calibration and validation of the model is performed. Using this steady state model the optimum salt pond to carnallite pond area ratio is deduced. This optimum ratio is defined as the optimum area ratio that maximizes the carnallite production per the total pond system area. This term, which could be expressed as tons per km2, presents the best pond system efficiency. The results show that a 1.88 ratio of salt to carnallite ponds area is the optimum ratio.