Summer Flushing Characteristics of Kuwait Bay

Abstract

Pokavanich, T. and Alosairi, Y., 2014. Summer flushing characteristics of Kuwait Bay.Flushing capability of an arid, shallow, semienclosed bay was investigated in this study through a well-validated, three-dimensional, numerical model. The numerical model, Delft3D-FLOW, was used to generate the hydrodynamics and transport characteristics of the water in Kuwait Bay. The Bay, located in the NW area of the Arabian Gulf and at the heart of the State of Kuwait, is a relatively shallow, mesotidal, hypersaline, inverse estuary. The Bay provides multifaceted functions, sustaining fast-growing cities and productive natural coastal ecosystems. However, the water-quality condition of the Bay has been rapidly degraded. The numerical models were driven, calibrated, and validated by realistic combined effects of tide, wind, and thermohaline circulation driven by measured data. Numerical tracer analysis was used to determine the flushing times at different parts of the Bay. Results suggest that the flushing characteristics of the Bay can be categorized into three main regimes, i.e. (1) the fastest flushing in the deeper areas close to the Bay mouth governed by strong, fluctuating tidal currents; (2) fast flushing at the intertidal areas north of the Bay mouth governed by wind-driven currents; and (3) relatively slower flushing at the inner part of the Bay driven by thermohaline circulation. Inclusion of the wind- and density-driven currents to the numerical model in this study significantly reduced the flushing time results from Kuwait Bay to 65 days, compared with much higher values estimated in previous studies.