Introduction

Abstract

Marine fog has a significant impact on human activities and the environment. A substantial portions of all accidents at sea worldwide occur in the presence of dense fog. Fog’s disruption of marine transport, harbor activities, coastal road traffic, and life threatening situations are often in the news. Fog transports droplets and their ions, aerosols, and microorganisms that alter the hydrologic, thermodynamic, nutrient, and toxicological properties of ecosystems in coastal regions. Fog also controls temperature and moisture conditions in coastal areas and consequently affects vegetation and especially forest evolution. Some of the highest degradations of air quality occur during fog under stable and stagnant anticyclonic conditions. In principle, fog forecast models should resolve a huge span of physical processes ranging from the characteristic 10⁻⁷ m scales of aerosols to synoptic processes with scales of 10⁶ m, which means the range of the smallest to the largest scales is on an order of 10¹³ m. The main variables and processes relevant to fog include aerosols and fog condensation nuclei; microphysics and precipitation; advection; synoptic conditions; air-sea interaction through surface fluxes of heat, latent heat, moisture, and momentum; air and sea surface temperature; ocean currents and upwelling; land-sea interactions and local circulations; characteristics of low marine inversion and entrainment; and coastal topography. The main goal of this book is to provide comprehensive understanding of the major processes leading to formation, evolution, and dissipation of fog by using observations, modeling, and forecasting. Discussed topics include fog observational in situ and remote sensing techniques, worldwide fog climatology, radiation and turbulence properties, microphysics and visibility parameterizations, effects of precipitation on fog, and deterministic and probabilistic fog modeling and forecasting.