Atmospheric river

narrow corridor or filament of concentrated moisture in the atmosphere

An atmospheric river is a narrow corridor or filament of concentrated moisture in the atmosphere. Other names for this phenomenon are tropical plume, tropical connection, moisture plume, water vapor surge, and cloud band.

Two wide photos showing a long stream of clouds ranging over the Pacific ocean
Composite satellite photos of an atmospheric river connecting Asia to North America in October 2017

Quotes

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  • The intense rainstorms sweeping in from the Pacific Ocean began to pound central California on Christmas Eve in 1861 and continued virtually unabated for 43 days.
    • Michael D. Dettinger research hydrologist for the U.S. geological Survey and and B. Lynn Ingram, professor of earth and planetary science at the University of California, Berkeley [ https://cw3e.ucsd.edu/wp-content/uploads/2013/10/Dettinger_Ingram_sciam13.pdf Huge flows of vapor in the atmosphere, dubbed “atmospheric rivers,” have unleashed massive floods every 200 years, and climate change could bring more of them] (2013-10)
  • Warmer atmospheric temperatures, in general, will mean the freezing levels are higher than they've been in the past. But while storms vary, even without climate change and some can be extra warm, just by natural situation, it's clear the background warming should increase the [freezing] levels. This makes for extra potential potency to the impact," he said. "The rivers are already high again, so this one's going to pack a wallop.
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