POLYGON experiment
Encyclopedia
The POLYGON experiment was a pioneer experiment in oceanography
conducted in middle of the Atlantic Ocean
during the 1970s. The experiment, led by Leonid Brekhovskikh
, was the first to establish the existence of so-called "mesoscale
eddies
", eddies at the 100-km and 100-day scale, which triggered the "mesoscale revolution". The existence of mesoscale eddies were predicted by Henry Stommel
in the 1960s, but there was no way to observe them with traditional sampling methods.
, from the Andreev Acoustics Institute, involving six research vessels and an extensive network of current meters. The flow meters were disposed in a cross, spanning a region of 113 by 113 nautical mile
s dubbed the "polygon". The experiment recorded temperature and flow, replacing the meters every 25 days, while taking care that the replacements would not create gaps in the data. The research vessels involved were the Akademik Kurchatov, the Dmitri Mendeleev, the Andrei Vil'kitskii, the Akademik Vernadskii, the Sergei Vavilov and the Pyotr Lebedev
.
Of the results, Brekhovskikh wrote in original breakthrough article "Even with somewhat less sophisticated gear than was desirable, the results... exceeded all expectations in terms of ... the significance of the scientific results obtained. Undoubtedly the experience... will be very useful in the preparation for the forthcoming international campaign MODE... It looks as though some largescale eddy or wave disturbances were travelling across the POLYGON site from east to west. Their scales were close to those of the planetary baroclinic Rossby waves
..."
, and the POLYMODE experiment by Andrei Monin
. Walter Munk
commented that the POLYGON experiment "ignited the mesoscale revolution [and that] MODE defined the new order" and that "oceanography has never been the same" since.
Oceanography
Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean...
conducted in middle of the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
during the 1970s. The experiment, led by Leonid Brekhovskikh
Leonid Brekhovskikh
Leonid Maksimovich Brekhovskikh was a Russian/Soviet scientist known for his work in acoustical and physical oceanography.-Life:...
, was the first to establish the existence of so-called "mesoscale
Mesoscale meteorology
Mesoscale meteorology is the study of weather systems smaller than synoptic scale systems but larger than microscale and storm-scale cumulus systems. Horizontal dimensions generally range from around 5 kilometers to several hundred kilometers...
eddies
Eddy (fluid dynamics)
In fluid dynamics, an eddy is the swirling of a fluid and the reverse current created when the fluid flows past an obstacle. The moving fluid creates a space devoid of downstream-flowing fluid on the downstream side of the object...
", eddies at the 100-km and 100-day scale, which triggered the "mesoscale revolution". The existence of mesoscale eddies were predicted by Henry Stommel
Henry Stommel
Henry Melson Stommel was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream that form the basis of physical oceanography today...
in the 1960s, but there was no way to observe them with traditional sampling methods.
Setup and results
POLYGON was led by Leonid BrekhovskikhLeonid Brekhovskikh
Leonid Maksimovich Brekhovskikh was a Russian/Soviet scientist known for his work in acoustical and physical oceanography.-Life:...
, from the Andreev Acoustics Institute, involving six research vessels and an extensive network of current meters. The flow meters were disposed in a cross, spanning a region of 113 by 113 nautical mile
Nautical mile
The nautical mile is a unit of length that is about one minute of arc of latitude along any meridian, but is approximately one minute of arc of longitude only at the equator...
s dubbed the "polygon". The experiment recorded temperature and flow, replacing the meters every 25 days, while taking care that the replacements would not create gaps in the data. The research vessels involved were the Akademik Kurchatov, the Dmitri Mendeleev, the Andrei Vil'kitskii, the Akademik Vernadskii, the Sergei Vavilov and the Pyotr Lebedev
Pyotr Lebedev (research vessel)
Pyotr Lebedev was a research vessel operated by the Soviet Union. The vessel was owned and operated by the Andreev Acoustics Institute, and was used to make hydrophysical observations of the Atlantic Ocean such as during the Polygon experiment...
.
Of the results, Brekhovskikh wrote in original breakthrough article "Even with somewhat less sophisticated gear than was desirable, the results... exceeded all expectations in terms of ... the significance of the scientific results obtained. Undoubtedly the experience... will be very useful in the preparation for the forthcoming international campaign MODE... It looks as though some largescale eddy or wave disturbances were travelling across the POLYGON site from east to west. Their scales were close to those of the planetary baroclinic Rossby waves
Rossby wave
Atmospheric Rossby waves are giant meanders in high-altitude winds that are a major influence on weather.They are not to be confused with oceanic Rossby waves, which move along the thermocline: that is, the boundary between the warm upper layer of the ocean and the cold deeper part of the...
..."
Follow up
POLYGON was followed by the MODE experiment (Mid Ocean Dynamics Experiment) led by Henry StommelHenry Stommel
Henry Melson Stommel was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream that form the basis of physical oceanography today...
, and the POLYMODE experiment by Andrei Monin
Andrei Monin
Andrei Sergeevich Monin was a Russian physicist, applied mathematician, and oceanographer. Monin was known for his contribution to statistical theory of turbulence and atmospheric physics. He served as the Director of the P.P. Shirshov Institute of Oceanology of the USSR Academy of Sciences...
. Walter Munk
Walter Munk
Walter Heinrich Munk is an American physical oceanographer. He is professor of geophysics emeritus and holds the Secretary of the Navy/Chief of Naval Operations Oceanography Chair at Scripps Institution of Oceanography in La Jolla, California.-Early life:Born in 1917 in Vienna, Austria-Hungary,...
commented that the POLYGON experiment "ignited the mesoscale revolution [and that] MODE defined the new order" and that "oceanography has never been the same" since.