Coastal meteorology encompasses phenomena that extend from about 100 km offshore to 100 km inland. Thus understanding the meteorology of the coastal zone combines knowledge of the interaction of marine and land atmospheric boundary layers, air-sea interaction, large-scale atmospheric dynamics, and the circulation of the coastal ocean. While there is considerable understanding of homogeneous marine and land boundary layers, application of this knowledge is complicated by the inherent heterogeneity of the coastal zone. Most coastal environments are modified by the adjacent ocean, the coastal topography and the land-sea thermal contrast. Complex feedbacks occur between the atmosphere, ocean and land. The thermal contrast between the land and sea creates the land-sea breeze, coastal atmospheric fronts, coastal ocean currents and upwelling. The convergence of marine air over the coastline can result in strong convection with heavy precipitation and runoff. A lateral, orographic boundary can accelerate the wind speed while constraining the flow parallel to the coast. Variations in the strength and direction of the wind depend on the exact nature of the orographic boundary. This results in highly variable temporal and spatial air-sea exchange processes that are dominated by scales of tens to hundreds of kilometers.
Recent research has focused on three categories of meteorological
phenomena: thermally-driven circulations; orographically-forced
events and land-falling storms.
[4]
These were discussed in detail
in a recent review of coastal meteorology by a National Research
Council (NRC) Panel on Coastal Meteorology [ Rotunno et al.,
1992], which forms the foundation for this review. While a
particular coastline or event may be dominated by one of these
phenomena, they are not mutually exclusive and most environments
are often affected by more than one of these systems [e.g.,
Wilczak et al., 1991]. In addition, each of these
phenomena is either controlled or substantially modified
by interaction with the coastal ocean.