2. Environmental Setting for Reef Building in the Red Sea

The Red Sea is a distinct marine system, which, due to its limited lateral extent, is strongly influenced by the surrounding arid and semiarid terrestrial environment. Among large marine bodies, it is unusually saline, owing to a high rate of evaporation relative to precipitation, and warm. The physical environment of the Red Sea has been subject to scientific research for more than a century, with considerable advances in understanding achieved in the past two decades. In this chapter, we review the current state of knowledge of the Red Sea’s physical/chemical system. The bulk of the chapter deals with the marine environment. Attention is given to a variety of topics, including: tides and lower-frequency motions of the sea surface, circulation over a range of space and time scales, the surface wave field, and the distributions of water properties, nutrients, chlorophyll-a (chl-a) and light. We also review the current understanding of atmospheric conditions affecting the Red Sea, focusing on how atmospheric circulation patterns of various scales influence the exchange of momentum, heat, and mass at the surface of the Red Sea. A subsection is devoted to geology and reef morphology, with a focus on reef-building processes in the Red Sea. Finally, because reef building and health are tightly linked with carbonate chemistry, we review the Red Sea carbonate system, highlighting recent advances in the understanding of this system.