An atmospheric river is a narrow corridor or filament of concentrated moisture in the atmosphere. Atmospheric rivers consist of narrow bands of enhanced water vapor transport, typically along the boundaries between large areas of divergent surface air flow, including some frontal zones in association with extratropical cyclones that form over the oceans.
The term was originally coined by researchers Reginald Newell and Young Zhu of the Massachusetts Institute of Technology in the early 1990s, to reflect the narrowness of the moisture plumes involved. Atmospheric rivers are typically several thousand kilometers long and only a few hundred kilometers wide, and a single one can carry a greater flux of water than the Earth's largest river, the Amazon River. There are typically 3–5 of these narrow plumes present within a hemisphere at any given time.
Atmospheric rivers have a central role in the global water cycle. On any given day, atmospheric rivers account for over 90% of the global meridional (north-south) water vapor transport, yet they cover less than 10% of the Earth's circumference.
They also are the major cause of extreme precipitation events which cause severe flooding in many mid-latitude, westerly coastal regions of the world, including the West Coast of North America, western Europe, and the west coast of North Africa.
- Pineapple Express, an atmospheric river which affects the West Coast of North America
- Tropical upper tropospheric trough, a band of moisture common in tropical regions
- ARkStorm, a hypothetical storm by the same name that could possibly affect California
- Great Flood of 1862 (massive flooding in US West)
- Zhu, Yong; Reginald E. Newell (1994). "Atmospheric rivers and bombs" (PDF). Geophys. Res. Lett. 21 (18): 1999–2002. Bibcode:1994GeoRL..21.1999Z. doi:10.1029/94GL01710.
- Zhu, Yong; Reginald E. Newell (1998). "A Proposed Algorithm for Moisture Fluxes from Atmospheric Rivers". Monthly Weather Review 126 (3): 725–735. Bibcode:1998MWRv..126..725Z. doi:10.1175/1520-0493(1998)126<0725:APAFMF>2.0.CO;2. ISSN 1520-0493.
- Kerr, Richard A. (28 July 2006). "Rivers in the Sky Are Flooding The World With Tropical Waters" (PDF). Science 313 (5786): 435. doi:10.1126/science.313.5786.435. PMID 16873624.
- White, Allen B. et al. (2009-10-08). The NOAA coastal atmospheric river observatory. 34th Conference on Radar Meteorology.
- Newell, Reginald E.; Nicholas E. Newell; Yong Zhu; Courtney Scott (1992). "Tropospheric rivers? – A pilot study". Geophys. Res. Lett. 19 (24): 2401–2404. Bibcode:1992GeoRL..19.2401N. doi:10.1029/92GL02916.
- Neiman, Paul J. et al. (2009-06-08). Landfalling Impacts of Atmospheric Rivers: From Extreme Events to Long-term Consequences (PDF). The 2010 Mountain Climate Research Conference.
- Neiman, Paul J. et al. (2008). "Diagnosis of an Intense Atmospheric River Impacting the Pacific Northwest: Storm Summary and Offshore Vertical Structure Observed with COSMIC Satellite Retrievals" (PDF). Monthly Weather Review 136 (11): 4398–4420. Bibcode:2008MWRv..136.4398N. doi:10.1175/2008MWR2550.1.
- Neiman, Paul J. et al. (2008). "Meteorological Characteristics and Overland Precipitation Impacts of Atmospheric Rivers Affecting the West Coast of North America Based on Eight Years of SSM/I Satellite Observations" (PDF). Journal of Hydrometeorology 9 (1): 22–47. Bibcode:2008JHyMe...9...22N. doi:10.1175/2007JHM855.1.
- Ralph, F. Martin et al. (2006). "Flooding on California’s Russian River: Role of atmospheric rivers" (PDF). Geophys. Res. Lett. 33 (13): L13801. Bibcode:2006GeoRL..3313801R. doi:10.1029/2006GL026689.
- "Atmospheric river of moisture targets Britain and Ireland". CIMSS Satellite Blog. November 19, 2009.
- Stohl, A.; Forster, C.; Sodermann, H. (March 2008). "Remote sources of water vapor forming precipitation on the Norwegian west coast at 60°N–a tale of hurricanes and an atmospheric river". Journal of Geophysical Research 113.
- Lavers, David A,; R. P. Allan; E. F. Wood; G. Villarini; D. J. Brayshaw; A. J. Wade (6 December 2011). "Winter floods in Britain are connected to atmospheric rivers" (PDF). Geophysical Research Letters 38. Bibcode:2011GeoRL..3823803L. doi:10.1029/2011GL049783. Retrieved 12 August 2012.
- NOAA Earth System Research Laboratory: Atmospheric River Information Page
- NOAA Earth System Research Laboratory: Atmospheric River Publications List
- NOAA Earth System Research Laboratory: Atmospheric Rivers (PDF brochure)
- NOAA News Online: NOAA Researchers Study Rivers of the Sky (2005)
- SSMI/AMSRE-derived Total Precipitable Water – Global — Animation showing current atmospheric rivers (University of Wisconsin CIMSS)
- GOES Eastern Pacific water vapor imagery — Naval Research Laboratory Monterey
- Worse floods ahead for UK as climate warms, say scientists