Understanding atmospheric rivers: characterization, impacts, drivers, and predictability

Abstract

Atmospheric rivers (ARs) are long and narrow corridors of concentrated moisture in the atmosphere that transport vast amounts of water vapor over long distances. These phenomena are important components of Earth's water cycle and play a significant role in shaping weather patterns and impacting climate conditions. ARs are typically several thousands of kilometers in length and a few hundred kilometers in width. They are characterized by a strong horizontal transport of water vapor, which can be equivalent to twice the flow of water in the Amazon River, the largest river on Earth. The moisture in ARs originates from tropical and subtropical regions and is transported poleward by prevailing winds in the mid-latitudes. When ARs make landfall, they interact with local topography, such as mountains and coastal ranges, leading to enhanced precipitation.