Fujiwhara effect
Encyclopedia
The Fujiwhara effect or Fujiwara interaction, named after Sakuhei Fujiwhara
, is a type of interaction between two nearby cyclonic
vortices
, causing them to appear to "orbit" each other.
The effect is often mentioned in relation to the motion of tropical cyclone
s, although the final merging of the two storms is uncommon. The effect becomes pronounced in these storms when they approach within about 1,500 km (900 mi) of each other and are at tropical storm strength or stronger.
, the Japan
ese meteorologist who initially described it in a 1921 paper about the motion of vortices in water.
. During the height of the season, Hurricane Humberto
and Hurricane Iris
took part in a brief Fujiwara interaction. Iris then began interacting with a third storm, Tropical Storm Karen, which orbited and later merged with the more intense Iris.
In 2004
, Lisa
absorbed a tropical disturbance as described in the Tropical Cyclone Report.
In 2005
, the remnant low of Tropical Depression Thirteen moved northward and then northeastward around a non-tropical low located to the north of the system. It briefly strengthened into Tropical Storm Lee. Thereafter, Lee weakened back to a tropical depression as it moved northeastward and northwestward around the eastern side of the non-tropical low and eventually absorbed the non-tropical low.
In the same year, Alpha was absorbed by Wilma
.
, Norbert absorbed Tropical Depression Eighteen-E.
In 2001
, Gil absorbed Henriette but associated convection totally dissipated during the merger and did not return afterwards.
In 2005
, Lidia
was absorbed by Max.
, Typhoon Pat and Tropical Storm Ruth completed a full orbit around their centroid before collapsing into a single cyclone.
In October 1997
, Typhoon Ivan and Typhoon Joan were a pair of super typhoons that interacted through the Fujiwara effect. The interaction affected their motion as Ivan was steered to the west, and Joan was steered more northerly.
In October 2006
, Severe Tropical Storm Wukong
absorbed Tropical Storm Sonamu south of Japan
.
In November 2007
, Typhoon Hagibis made a recurvature in the South China Sea towards Typhoon Mitag
northeast of the Philippines
.
In October 2009
, Typhoon Parma
interacted with Typhoon Melor
, affecting the movement of Parma. Parma was moving through the South China Sea
but made a recurvature move to southeastward, so it made its second and third landfall over northern Luzon. In addition, due to the interaction with Melor, Parma weakened into a tropical storm by October 4. Also in November 2009, Typhoon Nida
absorbed Tropical Depression 27W (Urduja) and become a powerful typhoon.
In August 2010
, a Fujiwara interaction occurred between Tropical Storm Namtheun and Severe Tropical Storm Lionrock. Namtheun turned southwestward while Lionrock turned eastward. Later, Namtheun weakened into a tropical depression in the Taiwan Strait
and was absorbed by Lionrock. At the mean time, Typhoon Kompasu
was near Okinawa
, Japan and did not take part in the Fujiwara interaction. Nevertheless, Kompasu disrupted the outflow of Namtheun and was partly responsible for the decay of Namtheun.
On July 2011
, Typhoon Ma-on
absorbed Tropical Storm Tokage. On September 16 of the same year, Typhoon Roke
weakened a weak tropical depression.
, Tropical Cyclone Fame began orbiting Tropical Cyclone Gula with the stronger storm, Gula, absorbing Fame.
scales) twins Cyclone Ron and Cyclone Susan started interacting on January 7. On January 9, Susan completely absorbed Ron.
Sakuhei Fujiwhara
was a Japanese meteorologist who became the namesake for the Fujiwhara effect. Novelist Jirō Nitta is his nephew and mathematician Masahiko Fujiwara is his grandnephew.-Early life:...
, is a type of interaction between two nearby cyclonic
Cyclone
In meteorology, a cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth. This is usually characterized by inward spiraling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere of the Earth. Most large-scale...
vortices
Vortex
A vortex is a spinning, often turbulent,flow of fluid. Any spiral motion with closed streamlines is vortex flow. The motion of the fluid swirling rapidly around a center is called a vortex...
, causing them to appear to "orbit" each other.
Description
When the cyclones approach each other, their centers will begin orbiting cyclonically about a point between the two systems. The two vortices will be attracted to each other, and eventually spiral into the center point and merge. When the two vortices are of unequal size, the larger vortex will tend to dominate the interaction, and the smaller vortex will orbit around it.The effect is often mentioned in relation to the motion of tropical cyclone
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
s, although the final merging of the two storms is uncommon. The effect becomes pronounced in these storms when they approach within about 1,500 km (900 mi) of each other and are at tropical storm strength or stronger.
Namesake
The effect is named after Sakuhei FujiwharaSakuhei Fujiwhara
was a Japanese meteorologist who became the namesake for the Fujiwhara effect. Novelist Jirō Nitta is his nephew and mathematician Masahiko Fujiwara is his grandnephew.-Early life:...
, the Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese meteorologist who initially described it in a 1921 paper about the motion of vortices in water.
Examples
North Atlantic
A few sets of examples can be found in the busy 1995 Atlantic hurricane season1995 Atlantic hurricane season
The 1995 Atlantic hurricane season was the third most active Atlantic hurricane season on record. It officially began on June 1, 1995, and lasted until November 30, 1995. These dates conventionally delimit the period of each year when most tropical cyclones form in the north Atlantic ocean...
. During the height of the season, Hurricane Humberto
Hurricane Humberto (1995)
Hurricane Humberto was the eighth named storm and fourth hurricane of the busy 1995 Atlantic hurricane season. This was the first time that the name "Humberto" was used as it replaced Hugo...
and Hurricane Iris
Hurricane Iris (1995)
Hurricane Iris was the ninth named tropical cyclone and fifth hurricane of an active 1995 Atlantic hurricane season. Iris was one of four storms to form nearly simultaneously in the Atlantic during the 1995 season. Forming on August 22, Iris slowly drifted across the Leeward Islands as a tropical...
took part in a brief Fujiwara interaction. Iris then began interacting with a third storm, Tropical Storm Karen, which orbited and later merged with the more intense Iris.
In 2004
2004 Atlantic hurricane season
The 2004 Atlantic hurricane season officially began on June 1, 2004, and lasted until November 30, 2004. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin...
, Lisa
Hurricane Lisa (2004)
Hurricane Lisa was a long-lived Cape Verde-type hurricane in the 2004 Atlantic hurricane season. It was the twelfth named storm, as well as the ninth and final hurricane of the season. Lisa formed on September 19 and spent nearly two weeks fluctuating between a tropical depression and a tropical...
absorbed a tropical disturbance as described in the Tropical Cyclone Report.
In 2005
2005 Atlantic hurricane season
The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, repeatedly shattering numerous records. The impact of the season was widespread and ruinous with an estimated 3,913 deaths and record damage of about $159.2 billion...
, the remnant low of Tropical Depression Thirteen moved northward and then northeastward around a non-tropical low located to the north of the system. It briefly strengthened into Tropical Storm Lee. Thereafter, Lee weakened back to a tropical depression as it moved northeastward and northwestward around the eastern side of the non-tropical low and eventually absorbed the non-tropical low.
In the same year, Alpha was absorbed by Wilma
Hurricane Wilma
Hurricane Wilma was the most intense tropical cyclone ever recorded in the Atlantic basin. Wilma was the twenty-second storm , thirteenth hurricane, sixth major hurricane, and fourth Category 5 hurricane of the record-breaking 2005 season...
.
Northeast Pacific
In 19901990 Pacific hurricane season
The 1990 Pacific hurricane season is the fifth most active season on record. The 1990 season officially started on May 15 in the eastern Pacific, and on June 1 in the central Pacific, and lasted until November 30. These dates conventionally delimit the period of each year when most tropical...
, Norbert absorbed Tropical Depression Eighteen-E.
In 2001
2001 Pacific hurricane season
The 2001 Pacific hurricane season was an event in tropical cyclone meteorology. The most notable storm that year was Hurricane Juliette, which caused devastating floods in Baja California, leading to 12 fatalities and $400 million worth of damage...
, Gil absorbed Henriette but associated convection totally dissipated during the merger and did not return afterwards.
In 2005
2005 Pacific hurricane season
The 2005 Pacific hurricane season officially began on May 15, 2005 in the eastern Pacific and on June 1, 2005 in the central Pacific, and lasted until November 30, 2005. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean...
, Lidia
Tropical Storm Lidia (2005)
Tropical Storm Lidia was the thirteenth tropical cyclone and twelfth named storm of the 2005 Pacific hurricane season. Lidia developed out of a tropical wave which was first noted on September 10 while entering the eastern Pacific basin...
was absorbed by Max.
Northwest Pacific
In September 19941994 Pacific typhoon season
The 1994 Pacific typhoon season was an active season in the annual cycle of tropical cyclone formation in the Western North Pacific, with a total of 41 tropical cyclones during the course of the season. The season had no official bounds and it ran year-round in 1994, but most tropical cyclones tend...
, Typhoon Pat and Tropical Storm Ruth completed a full orbit around their centroid before collapsing into a single cyclone.
In October 1997
1997 Pacific typhoon season
The 1997 Pacific typhoon season has no official bounds; it ran year-round in 1997, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern...
, Typhoon Ivan and Typhoon Joan were a pair of super typhoons that interacted through the Fujiwara effect. The interaction affected their motion as Ivan was steered to the west, and Joan was steered more northerly.
In October 2006
2006 Pacific typhoon season
The 2006 Pacific typhoon season had no official bounds; it ran year-round in 2006, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November...
, Severe Tropical Storm Wukong
Tropical Storm Wukong (2006)
Severe Tropical Storm Wukong was a slow moving tropical cyclone which produced torrential rains over Japan. The tenth named storm of the 2006 Pacific typhoon season, Wukong developed out of a tropical depression over the open waters of the western Pacific Ocean...
absorbed Tropical Storm Sonamu south of Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
.
In November 2007
2007 Pacific typhoon season
The 2007 Pacific typhoon season was a below average season which featured 24 named storms and 14 typhoons, compared to the average of 27 and 17 respectively. had no official bounds; it ran year-round in 2007, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and...
, Typhoon Hagibis made a recurvature in the South China Sea towards Typhoon Mitag
Typhoon Mitag (2007)
Typhoon Mitag was a strong typhoon that caused deadly flooding in the Philippines.-Meteorological history:...
northeast of the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
.
In October 2009
2009 Pacific typhoon season
The 2009 Pacific typhoon season was the period that tropical cyclones formed in the Western Pacific Ocean. The season ran throughout the year during 2009, with most tropical cyclones forming between May and November. The scope of this article is limited to the Pacific Ocean, north of the equator...
, Typhoon Parma
Typhoon Parma
Typhoon Parma was the second typhoon to affect the Philippines within the span of a week during September 2009....
interacted with Typhoon Melor
Typhoon Melor (2009)
Typhoon Melor was the second category 5 typhoon in 2009...
, affecting the movement of Parma. Parma was moving through the South China Sea
South China Sea
The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around...
but made a recurvature move to southeastward, so it made its second and third landfall over northern Luzon. In addition, due to the interaction with Melor, Parma weakened into a tropical storm by October 4. Also in November 2009, Typhoon Nida
Typhoon Nida (2009)
Typhoon Nida was the strongest storm of the 2009 Pacific typhoon season and the most intense storm of 2009...
absorbed Tropical Depression 27W (Urduja) and become a powerful typhoon.
In August 2010
2010 Pacific typhoon season
The 2010 Pacific typhoon season was the least active Pacific typhoon season, in terms of the number of named storms and typhoons, on record, due to a moderate La Niña event...
, a Fujiwara interaction occurred between Tropical Storm Namtheun and Severe Tropical Storm Lionrock. Namtheun turned southwestward while Lionrock turned eastward. Later, Namtheun weakened into a tropical depression in the Taiwan Strait
Taiwan Strait
The Taiwan Strait or Formosa Strait, formerly known as the Black Ditch, is a 180-km-wide strait separating Mainland China and Taiwan. The strait is part of the South China Sea and connects to East China Sea to the northeast...
and was absorbed by Lionrock. At the mean time, Typhoon Kompasu
Typhoon Kompasu (2010)
Typhoon Kompasu was the Category 3 typhoon that moved along Okinawa, Japan and west coast of the Korean Peninsula before striking the Seoul Metropolitan Area in early-September 2010...
was near Okinawa
Okinawa Prefecture
is one of Japan's southern prefectures. It consists of hundreds of the Ryukyu Islands in a chain over long, which extends southwest from Kyūshū to Taiwan. Okinawa's capital, Naha, is located in the southern part of Okinawa Island...
, Japan and did not take part in the Fujiwara interaction. Nevertheless, Kompasu disrupted the outflow of Namtheun and was partly responsible for the decay of Namtheun.
On July 2011
2011 Pacific typhoon season
The 2011 Pacific typhoon season was the time of the year in which tropical cyclones form in the Western Pacific Ocean. The season ran throughout 2011 with most tropical cyclones forming between May and November. The scope of this article is limited to the Pacific Ocean to the north of the equator...
, Typhoon Ma-on
Typhoon Ma-on (2011)
Typhoon Ma-on was a powerful typhoon that affected southern Japan. It was the sixth named storm and second typhoon of the 2011 Pacific typhoon season....
absorbed Tropical Storm Tokage. On September 16 of the same year, Typhoon Roke
Typhoon Roke (2011)
Typhoon Roke was a persistent and powerful tropical cyclone that affected Japan, where some areas were damaged by another typhoon just a few weeks ago...
weakened a weak tropical depression.
Southwest Indian Ocean
In 20082007-08 South-West Indian Ocean cyclone season
The 2007–08 South-West Indian Ocean cyclone season was an event in the annual cycle of tropical cyclone formation. It began on November 15, 2007, and ended on April 30, 2008, with the exception for Mauritius and the Seychelles, which ended May 15...
, Tropical Cyclone Fame began orbiting Tropical Cyclone Gula with the stronger storm, Gula, absorbing Fame.
South Pacific Ocean
In early January 1998, the category 5 (in both Australian and SSHSSaffir-Simpson Hurricane Scale
The Saffir–Simpson Hurricane Scale , or the Saffir–Simpson Hurricane Wind Scale , classifies hurricanes — Western Hemisphere tropical cyclones that exceed the intensities of tropical depressions and tropical storms — into five categories distinguished by the intensities of their sustained winds...
scales) twins Cyclone Ron and Cyclone Susan started interacting on January 7. On January 9, Susan completely absorbed Ron.