Atmospheric river
Encyclopedia
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 cyclone
s that form over the oceans.
The term was originally coined by researchers Reginald Newell and Yong 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 flood
ing 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.
Atmosphere
An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...
. Atmospheric rivers consist of narrow bands of enhanced water vapor
Water vapor
Water vapor or water vapour , also aqueous vapor, is the gas phase of water. It is one state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Under typical atmospheric conditions, water vapor is continuously...
transport, typically along the boundaries between large areas of divergent surface air flow, including some frontal zones in association with extratropical cyclone
Extratropical cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth having neither tropical nor polar characteristics, and are connected with fronts and...
s that form over the oceans.
The term was originally coined by researchers Reginald Newell and Yong Zhu of the Massachusetts Institute of Technology
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...
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
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
. 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
Water cycle
The water cycle, also known as the hydrologic cycle or H2O cycle, describes the continuous movement of water on, above and below the surface of the Earth. Water can change states among liquid, vapor, and solid at various places in the 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
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
events which cause severe flood
Flood
A flood is an overflow of an expanse of water that submerges land. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water...
ing 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.
See also
- Pineapple ExpressPineapple ExpressPineapple Express is a non-technical term for a meteorological phenomenon characterized by a strong and persistent flow of atmospheric moisture and associated heavy rainfall from the waters adjacent to the Hawaiian Islands and extending to any location along the Pacific coast of North America...
, an atmospheric river which affects the West Coast of North America - Tropical upper tropospheric troughTropical Upper Tropospheric TroughA tropical upper tropospheric trough , also known as the mid-oceanic trough, is a trough situated in upper-level tropics. Its formation is usually caused by the intrusion of energy and wind from the mid-latitudes into the tropics. It can also develop from the inverted trough adjacent to an upper...
, a band of moisture common in tropical regions - ARkStormARkStormAn ARkStorm is a hypothetical but scientifically realistic "superstorm" scenario developed and published by the United States Geological Survey, Multi Hazards Demonstration Project...
, a hypothetical storm by the same name that could possibly affect California
External links
- 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
