Typhoon Agnes, known in the
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
as Typhoon Pining, produced among the heaviest rains recorded during the 20th century in
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...
, with falling over a two-day span. The storm originated as a
tropical depression
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...
near
Guam
Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...
on August 25, 1981. Moving along a west-northwest to northwest track, the system gradually strengthened as deep
convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...
organized around it. The depression
was assigned the name ''Agnes'' on August 27 following the development of gale-force winds. Further intensification to typhoon-status occurred by August 29. Agnes attained its peak intensity on August 31 over the
East China Sea
The East China Sea is an arm of the Western Pacific Ocean, located directly offshore from East China. It covers an area of roughly . The sea’s northern extension between mainland China and the Korean Peninsula is the Yellow Sea, separated b ...
as a
Category 2-equivalent on the
Saffir–Simpson hurricane wind scale with winds of 175 km/h (110 mph). Subsequent interaction with a
mid-latitude trough induced an
extratropical transition
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth. Extratropical cyclones are capable of p ...
as the cyclone slowed and turned north. The system had lost most of its tropical characteristics by September 1, with the majority of convection
sheared northeast over
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...
and Japan. Agnes later accelerated northeast and completed its transition on September 3. The remnants continued along this course, impacting northern Japan and the
Kamchatka Peninsula
The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and we ...
before last being noted on September 6 near the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
.
Throughout the course of Agnes' existence, several countries were affected by torrential rains and typhoon-force winds. Hardest hit was South Korea where record-breaking rains triggered widespread flooding. More than 12,000 structures were damaged or destroyed by the storm and 191,000 acres (77,300 hectares) of farmland was inundated. A total of 113 people died in the country while damage reached $134 million. Taiwan saw similarly destructive rains which left 32 people dead or missing. A further 14 people died in mainland China where
coastal flooding
Coastal flooding normally occurs when dry and low-lying land is submerged by seawater. The range of a coastal flooding is a result of the elevation of floodwater that penetrates the inland which is controlled by the topography of the coastal land ...
from the typhoon's slow movement coincided with the
spring tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another.
Tide tables ca ...
, resulting in the greatest
storm surge
A storm surge, storm flood, tidal surge, or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low-pressure weather systems, such as cyclones. It is measured as the rise in water level above the n ...
since 1949 along the
Yangtze
The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows ...
estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...
and
Hangzhou Bay
Hangzhou Bay, or the Bay of Hangzhou (), is a funnel-shaped inlet of the East China Sea, bordered by the province of Zhejiang and the municipality of Shanghai, which lies north of the Bay. The Bay extends from the East China Sea to its head a ...
. Much of Japan saw rains from the storm, though no significant damage or loss of life took place in the country.
Meteorological history
On August 23, 1981, following several days of tranquil weather, a
tropical upper tropospheric trough A tropical upper tropospheric trough (TUTT), also known as the mid-oceanic trough, is a trough situated in the upper-level (at about 200 hPa) tropics. Its formation is usually caused by the intrusion of energy and wind from the mid-latitudes into th ...
(TUTT) began building westward from the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
, near
Wake Island
Wake Island ( mh, Ānen Kio, translation=island of the kio flower; also known as Wake Atoll) is a coral atoll in the western Pacific Ocean in the northeastern area of the Micronesia subregion, east of Guam, west of Honolulu, southeast of To ...
. Over the following 36 hours, an expansive area of
convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...
developed southwest of the organizing TUTT. On August 25, surface observations on
Guam
Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...
in the
Mariana Islands
The Mariana Islands (; also the Marianas; in Chamorro: ''Manislan Mariånas'') are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly dormant volcanic mountains in the northwestern Pacific Ocean, betw ...
indicated the presence of a
low-pressure system
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible ...
.
Coinciding with this, the
Japan Meteorological Agency
The , abbreviated JMA, is an agency of the Ministry of Land, Infrastructure, Transport and Tourism. It is charged with gathering and providing results for the public in Japan that are obtained from data based on daily scientific observation an ...
(JMA) declared the formation of a tropical depression at 06:00
UTC.
Weather reconnaissance
Weather reconnaissance is the acquisition of weather data used for research and planning. Typically the term reconnaissance refers to observing weather from the air, as opposed to the ground.
Methods
Aircraft
Helicopters are not built to w ...
missions throughout the day indicated a 1006
mbar
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea leve ...
(hPa; ) center west of Guam, prompting the
Joint Typhoon Warning Center
The Joint typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South P ...
(JTWC) to issue a
Tropical Cyclone Formation Alert
A Tropical Cyclone Formation Alert (TCFA) is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Fleet Weather Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone forming ...
. Following improvement in the convective structure, the JTWC began warning on the cyclone as ''Tropical Depression 18W'' at 18:00 UTC, at which time the depression was situated roughly 665 km (415 mi) west-northwest of Guam.
Tracking west-northwest and later northwest around the southwestern edge of a
subtropical ridge
The horse latitudes are the latitudes about 30 degrees north and south of the Equator. They are characterized by sunny skies, calm winds, and very little precipitation. They are also known as Subtropics, subtropical ridges, or highs. It is a h ...
, steady intensification of the cyclone ensued. Early on August 27, a reconnaissance plane measured a central pressure of 994 mbar (hPa; ) and flight-level winds of , indicating the system had become a tropical storm. In light of this, the JTWC
assigned the name ''Agnes'' to the storm.
Additionally due to its proximity to the
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
, the
dubbed the system with the local name ''Pining''. Strengthening occurred at a climatological rate, with Agnes attaining typhoon-status on August 29. A large,
banding eye-feature developed within the core of Agnes as it approached the
Ryukyu Islands
The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yonaguni ...
of southwestern Japan. The storm passed 170 km (105 mi) south of
Okinawa
is a prefecture of Japan. Okinawa Prefecture is the southernmost and westernmost prefecture of Japan, has a population of 1,457,162 (as of 2 February 2020) and a geographic area of 2,281 km2 (880 sq mi).
Naha is the capital and largest city ...
around 06:00 UTC on August 30 and emerged over the
East China Sea
The East China Sea is an arm of the Western Pacific Ocean, located directly offshore from East China. It covers an area of roughly . The sea’s northern extension between mainland China and the Korean Peninsula is the Yellow Sea, separated b ...
. Early on August 31, Agnes achieved its peak strength with winds of 175 km/h (110 mph) and an estimated central pressure of 947 mbar (hPa; ). This ranked it as a
Category 2-equivalent on the
Saffir–Simpson hurricane wind scale.
The JMA estimated the system to have been slightly weaker, with ten-minute sustained winds of 150 km/h (90 mph) and a pressure of 950 mbar (hPa; ).
As the storm moved over the East China Sea on September 1, Agnes began to interact with a mid-latitude trough situated south of
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...
and began a prolonged
extratropical transition
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth. Extratropical cyclones are capable of p ...
. Increasing
wind shear
Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal ...
exposed the center of the typhoon and displaced convection to the north and east. Subsequent slowing of the cyclone's forward speed as it turned northward resulted in an extended period of heavy rain for much of South Korea. The JTWC estimated Agnes to have become predominantly extratropical by the end of September 1, coinciding with the system weakening below typhoon intensity.
The JMA, however, maintained the storm as a tropical system as it began moving northwest. The diminishing cyclone moved over the
Korea Strait
The Korea Strait is a sea passage in East Asia between Korea and Japan, connecting the East China Sea, the Yellow Sea and the Sea of Japan in the northwest Pacific Ocean. The strait is split by the Tsushima Island into the Western Channel and t ...
on September 3 and completed its extratropical transition that afternoon. Accelerating over the
Sea of Japan
The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it h ...
, the remnant storm deepened slightly before striking the northern Japanese island of
Hokkaido
is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel.
The la ...
on September 4 with an estimated pressure of 976 mbar (hPa; ). After moving over the
Sea of Okhotsk
The Sea of Okhotsk ( rus, Охо́тское мо́ре, Ohótskoye móre ; ja, オホーツク海, Ohōtsuku-kai) is a marginal sea of the western Pacific Ocean. It is located between Russia's Kamchatka Peninsula on the east, the Kuril Islands ...
, Agnes impacted the
Kamchatka Peninsula
The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and we ...
of Russia on September 5. The system then moved over the open waters of the North Pacific and was last noted near the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
on September 6.
Impact
Japan
On August 30, Typhoon Agnes moved through the southern Ryukyu Islands, bringing strong winds and heavy rain to the region. Several islands received more than of rain, and a peak value of was measured on
Ishigaki Island
, also known as ''Ishigakijima'', is a Japanese island south-west of Okinawa Hontō and the second-largest island of the Yaeyama Island group, behind Iriomote Island. It is located approximately south-west of Okinawa Hontō. It is within the ...
.
Despite passing through as a typhoon, only
Tokashiki received winds of such intensity with a peak gust of . A few other islands reported winds greater than .
After moving over the Sea of Japan, the storm's remnants brought heavy rains to much of Japan the day after a 6.6 ''
Mw''
earthquake
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
rocked eastern parts of the country. Air and sea transportation across the
Korean Strait
The Korea Strait is a sea passage in East Asia between Korea and Japan, connecting the East China Sea, the Yellow Sea and the Sea of Japan in the northwest Pacific Ocean. The strait is split by the Tsushima Island into the Western Channel and t ...
was cancelled for September 3. Landslides were reported across
Kyushu
is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surroun ...
, though no casualties occurred.
[ ] On
Shin-Kamigotō, Nagasaki, rain fell at rates of per hour on September 3 as Agnes passed to the north.
Rainfall in the mainland peaked at on
Chausuyama in
Aichi Prefecture
is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,552,873 () and a geographic area of with a population density of . Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefectur ...
.
China and Taiwan
Though Agnes did not directly impact Taiwan, prolonged southwesterly flow associated with the typhoon brought torrential rains to the island. Flooding in southern Taiwan was considered the worst in 30 years; 32 people were killed or left missing.
More than of rain fell in the cities of
Chiayi
Chiayi (, Taigi POJ: ''Ka-gī''; ), officially known as Chiayi City, is a city located in the plains of southwestern Taiwan. Formerly called ''Kagee'' during the late Qing dynasty and ''Kagi'' during the Japanese era (), its historical name i ...
,
Tainan
Tainan (), officially Tainan City, is a Special municipality (Taiwan), special municipality in southern Taiwan facing the Taiwan Strait on its western coast. Tainan is the oldest city on the island and also commonly known as the "Capital City" ...
,
Kaohsiung
Kaohsiung City (Mandarin Chinese: ; Wade–Giles: ''Kao¹-hsiung²;'' Pinyin: ''Gāoxióng'') is a special municipality located in southern Taiwan. It ranges from the coastal urban center to the rural Yushan Range with an area of . Kaohsi ...
, and
Pingtung. Flood waters, reaching depths of , inundated 238,256 acres (96,419 hectares) of farmland and destroyed 140 homes. An estimated 3,000 people were left homeless.
Significant water rise occurred along
Yangtze
The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows ...
estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...
and
Hangzhou Bay
Hangzhou Bay, or the Bay of Hangzhou (), is a funnel-shaped inlet of the East China Sea, bordered by the province of Zhejiang and the municipality of Shanghai, which lies north of the Bay. The Bay extends from the East China Sea to its head a ...
in mainland China as Agnes remained just east of the area for 36 hours and the coincidence of the
spring tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another.
Tide tables ca ...
. A peak
storm surge
A storm surge, storm flood, tidal surge, or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low-pressure weather systems, such as cyclones. It is measured as the rise in water level above the n ...
of was measured in the region with continuous onshore flow,
the highest since 1949;
conversely, in areas with continuous offshore flow, water levels fell by . Model simulations of the event estimated that a surge affected the
Waigaoqiao Free Trade Zone Shanghai Waigaoqiao Free Trade Zone (), was the first Free Trade Zone to be established in China. It is situated in the North East of Pudong District, near the end of Metro Line 6. It was incorporated as part of the newly developed China (Shanghai) ...
in
Shanghai
Shanghai (; , , Standard Mandarin pronunciation: ) is one of the four direct-administered municipalities of the People's Republic of China (PRC). The city is located on the southern estuary of the Yangtze River, with the Huangpu River flow ...
.
Offshore, 300 vessels sank while the resulting inland floods killed 14 people.
Authorities in Shanghai mobilized 100,000 personnel to limit the extent of the floods as 200 sections of seawall collapsed. According to local newspapers, 59,700 acres (24,100 hectares) of farmland flooded and 4,280 homes were damaged. Losses were estimated in the millions of dollars.
[ ]
High winds downed many trees across the region and debris littered the streets of Shanghai.
United States President
The president of the United States (POTUS) is the head of state and head of government of the United States of America. The president directs the executive branch of the federal government and is the commander-in-chief of the United State ...
Jimmy Carter
James Earl Carter Jr. (born October 1, 1924) is an American politician who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party (United States), Democratic Party, he previously served as th ...
, wrapping up an inspection of the
Chinese Navy
The People's Liberation Army Navy (PLAN; ), also known as the People's Navy, Chinese Navy, or PLA Navy, is the maritime service branch of the People's Liberation Army.
The PLAN traces its lineage to naval units fighting during the Chine ...
, was scheduled to take a cruise out of the
Huangpu River
The Huangpu (), formerly romanized as Whangpoo, is a river flowing north through Shanghai. The Bund and Lujiazui are located along the Huangpu River.
The Huangpu is the biggest river in central Shanghai, with the Suzhou Creek being its maj ...
; however, the typhoon forced the vessel to remain at port.
South Korea
Between September 1 and 3, torrential rains affected much of South Korea, with the heaviest falling well-ahead of the storm itself. Regarded as the heaviest on record in the 20th century, at least fell over a two-day span in the country, resulting in tremendous
flash flood
A flash flood is a rapid flooding of low-lying areas: washes, rivers, dry lakes and depressions. It may be caused by heavy rain associated with a severe thunderstorm, hurricane, or tropical storm, or by meltwater from ice or snow flowing o ...
ing and landslides.
This surpassed the previous two-day record of measured in 1928 in
Seoul
Seoul (; ; ), officially known as the Seoul Special City, is the capital and largest metropolis of South Korea.Before 1972, Seoul was the ''de jure'' capital of the Democratic People's Republic of Korea (North Korea) as stated iArticle 103 ...
.
A record-breaking 24‑hour rainfall of was also measured; however, this was later greatly surpassed by
Typhoon Rusa in
2002
File:2002 Events Collage.png, From left, clockwise: The 2002 Winter Olympics are held in Salt Lake City; Queen Elizabeth The Queen Mother and her daughter Princess Margaret, Countess of Snowdon die; East Timor gains East Timor independence, indepe ...
which produced during the same time span. The coastal counties of
Jangheung
Jangheung County (''Jangheung-gun'') is a county in South Jeolla Province, South Korea.
Slow city
In 2007 Jangheung was designated as a slow city. It was the first slow city designation in Asia.
Spot for filming
''Festival'' (1996) was filmed ...
,
Haenam
Haenam (''Haenam-gun'') is a county in South Jeolla Province, South Korea.
The capital of Haenam-gun is Haenam-eup (Haenam town).
The economy of the county is based mainly on agriculture, with rice and radish being the two most common crops.
Hist ...
, and
Goheung
Goheung County (''Goheung-gun'') is a Administrative divisions of South Korea, county in Jeollanam-do Province, South Korea.
Naro Space Center
The Naro Space Center was completed during 2008 in southern Goheung and is operated by the state-run Ko ...
all saw approximately half of their annual precipitation, between , in one day's time. In addition to the rains, winds up to were measured.
Communications with severed with towns along the southwestern coastline as roads and rail lines were washed away. Thousands of residents sought refuge by moving to higher ground.
[ ] The Korean relief center reported that 762 homes were destroyed and another 11,700 flooded due to the storm.
[ ] Other reports indicated that upwards of 5,900 homes were destroyed.
More than 191,000 acres (77,300 hectares) of farmland was washed out.
Throughout South Korea, 113 people died.
Most of the deaths resulted from landslides, swollen rivers, and collapsed embankments.
Total damage in the country amounted to $134 million, with agriculture accounting for at least $24 million.
Additionally, 28,000 people were left homeless.
The disaster relief agency Hope Bridge provided 7.5 billion
won ($10.2 million) in aid to areas affected by the storm.
See also
*
1981 Pacific typhoon season
The 1981 Pacific typhoon season was a slightly above average season that produced 29 tropical storms, 13 typhoons and two intense typhoons. The season ran throughout 1981, though most tropical cyclones typically develop between May and October.Ga ...
*
Typhoon Maemi
Typhoon Maemi () or (), known in the Philippines as Typhoon Pogi, was the most powerful typhoon to strike South Korea since record-keeping began in the country in 1904. Maemi formed on September 4, 2003 from a disturbance in a monsoon troug ...
– The strongest recorded typhoon to strike South Korea
*
List of wettest tropical cyclones by country
This is a list of wettest tropical cyclones by country, using all known available sources. Data is most complete for Australia, Cuba, Dominican Republic, Japan, Hong Kong, Mexico, Taiwan, Micronesia's Yap and Chuuk, and the United States, with ...
**
Typhoon Rusa – Surpassed Agnes as the wettest tropical cyclone in South Korea in 2002
**
Tropical Storm Nakri (2014) – The wettest-known tropical cyclone in South Korea as of 2014
Notes
References
{{1981 Pacific typhoon season buttons
Agnes
Typhoon Agnes
Agnes 1981
Agnes 1981
Agnes 1981
Agnes 1981
Agnes 1981
Agnes