Atmospheric Rivers: The Earth’s Highway for Water Vapor Transport

An atmospheric river is frequently mentioned in the news when storms develop. These atmospheric rivers are a true wonder of nature. High above us, vast streams of water vapor travel across the atmosphere, guided by unique meteorological forces that shape our planet's climate and weather patterns.

By seeing the term “atmospheric river,” you may imagine a massive river flowing in the sky. But answering the question “What is an atmospheric river” requires more detail and explanation. Fear not, as we have the answers for you below.

What Is An Atmospheric River?

Atmospheric rivers are key atmospheric phenomena that transport vast amounts of water vapor from the tropics toward mid-latitude and polar regions. These streamlined, elongated pathways play a significant role in the global water cycle, accounting for approximately 90% of the poleward water vapor transport from the Equator.

At any given time, there may be four to five atmospheric rivers occurring simultaneously across the globe. The amount of water vapor within these atmospheric rivers can be close to five times the average flow of the Mississippi River, making them crucial players in shaping precipitation patterns and water distribution worldwide.