Atmospheric river, a term encompassing different meteorological patterns

Abstract

The study of atmospheric rivers (ARs) and their impacts on extreme precipitation are currently of great research interest in view of their clear socioeconomical implications. However, studies of this type generally contain caveats. The first of these is of a meteorological nature, and is concerned with the diversity of the different meteorological patterns that can be associated in the phenomenological definition, in that there is no guarantee that all so-called ARs follow the same one. The second concern involves the initial definition of an AR, which implicitly assumes the subtropical origin of the atmospheric moisture that feeds it. To date, it has been observed that in many cases of ARs, most of the moisture originates in regions at higher latitudes. The aim of this article is to open a debate on these two aspects by using well-known examples of ARs which fit different meteorological patterns, and showing a climatology of the moisture sources that feed ARs.