![Kanto plain](https://upload.wikimedia.org/wikipedia/commons/4/47/Kanto_plain.png)
The is the largest plain in
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
, and is located in the
Kantō region
The is a geographical area of Honshu, the largest island of Japan. In a common definition, the region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba and Kanagawa. Slight ...
of central
Honshū
, historically called , is the largest and most populous island of Japan. It is located south of Hokkaidō across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyūshū across the Kanmon Straits. The island separa ...
. The total area of 17,000 km
2 covers more than half of the region extending over
Tokyo
Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.468 ...
,
Saitama Prefecture
is a landlocked prefecture of Japan located in the Kantō region of Honshu. Saitama Prefecture has a population of 7,338,536 (1 January 2020) and has a geographic area of 3,797 km2 (1,466 sq mi). Saitama Prefecture borders Tochigi Prefecture ...
,
Kanagawa Prefecture
is a prefecture of Japan located in the Kantō region of Honshu. Kanagawa Prefecture is the second-most populous prefecture of Japan at 9,221,129 (1 April 2022) and third-densest at . Its geographic area of makes it fifth-smallest. Kana ...
,
Chiba Prefecture
is a prefecture of Japan located in the Kantō region of Honshu. Chiba Prefecture has a population of 6,278,060 (1 June 2019) and has a geographic area of . Chiba Prefecture borders Ibaraki Prefecture to the north, Saitama Prefecture to the ...
,
Gunma Prefecture
is a prefecture of Japan located in the Kantō region of Honshu. Gunma Prefecture has a population of 1,937,626 (1 October 2019) and has a geographic area of 6,362 km2 (2,456 sq mi). Gunma Prefecture borders Niigata Prefecture and Fukushima ...
,
Tochigi Prefecture
is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Tochigi Prefecture has a population of 1,943,886 (1 June 2019) and has a geographic area of 6,408 Square kilometre, km2 (2,474 Square mile, sq mi). Tochigi ...
and
Ibaraki Prefecture
is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Ibaraki Prefecture has a population of 2,871,199 (1 June 2019) and has a geographic area of . Ibaraki Prefecture borders Fukushima Prefecture to the north, ...
.
Geography
The northern limit borders on the
Abukuma Highlands
The or Abukuma Mountains is a highland area of Japan that extends from the southern part of Miyagi Prefecture to the eastern part of Fukushima Prefecture and then to the northern part of Ibaraki Prefecture
is a prefecture of Japan locat ...
,
Yamizo Mountain Range, Ashio Mountain Range, and a volcanic field associated with the Nasu Volcanic Belt. The western coincides with the
Kantō Mountain Range and the southern edge is defined by the
Bōsō Peninsula
The is a peninsula that encompasses the entirety of Chiba Prefecture on Honshu, the largest island of Japan. It is part of the Greater Tokyo Area. It forms the eastern edge of Tokyo Bay, separating it from the Pacific Ocean. The peninsula covers ...
, the
Miura Hills,
Tokyo Bay
is a bay located in the southern Kantō region of Japan, and spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. Tokyo Bay is connected to the Pacific Ocean by the Uraga Channel. The Tokyo Bay region is both the most populous a ...
, and
Sagami Bay
lies south of Kanagawa Prefecture in Honshu, central Japan, contained within the scope of the Miura Peninsula, in Kanagawa, to the east, the Izu Peninsula, in Shizuoka Prefecture, to the west, and the Shōnan coastline to the north, while th ...
. The Kashima Sea and
Kujūkuri Beach
is a sandy beach that occupies much of the northeast coast of the Bōsō Peninsula in Chiba Prefecture, Japan. The beach is approximately long, making it the second longest beach in Japan. Kujūkuri Beach is a popular swimming and surfing dest ...
define the eastern end of the plain. Most of the rivers originate in the northern or western mountain ranges and flow east or southeast into the
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
,
Tokyo Bay
is a bay located in the southern Kantō region of Japan, and spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. Tokyo Bay is connected to the Pacific Ocean by the Uraga Channel. The Tokyo Bay region is both the most populous a ...
, or
Sagami Bay
lies south of Kanagawa Prefecture in Honshu, central Japan, contained within the scope of the Miura Peninsula, in Kanagawa, to the east, the Izu Peninsula, in Shizuoka Prefecture, to the west, and the Shōnan coastline to the north, while th ...
. In the central part of the plain is the
Tone River
The is a river in the Kantō region of Japan. It is in length (the second longest in Japan after the Shinano) and has a drainage area of (the largest in Japan). It is nicknamed Bandō Tarō (); ''Bandō'' is an obsolete alias of the Kantō ...
; in the northern part the
Watarase River
The is a major river in the northern Kantō region of Japan. A tributary of the Tone River, it is in length and drains an area of .Kinu River
, is a river on the main island of Honshu in Japan. It flows from the north to the south on the Kantō plain, merging with . At 176.7 km in length, it is the longest tributary of Tone-gawa. From ancient times, it has been known to cause flood ...
, Kokai River,
Naka River, and
Kuji River
is a river in Fukushima Prefecture, Tochigi Prefecture and Ibaraki Prefecture, Japan. It rises at the northern slope of Mount Yamizo, where the border of these three prefectures is located, and flows into Pacific Ocean at Hitachi and Tokai ...
; and in the southern part the
Arakawa River
or Ara River may refer to:
* Arakawa River (Kanto)
or Ara River may refer to:
* Arakawa River (Kanto), which flows from Saitama Prefecture and through Tokyo to Tokyo Bay
* Arakawa River (Uetsu), which flows from Yamagata Prefecture and throu ...
,
Tama River
The is a major river in Yamanashi, Kanagawa and Tokyo Prefectures on Honshū, Japan. It is officially classified as a Class 1 river by the Japanese government. Its total length is , and the total of the river's basin area spans .
The rive ...
, and
Sagami River
The is a river in Kanagawa and Yamanashi Prefectures on the island of Honshū, Japan.
The upper reaches of the river in Yamanashi prefecture are also sometimes known as the , and the portion near the river mouth as the . The river overall was ...
. Of these rivers, the
Tone River
The is a river in the Kantō region of Japan. It is in length (the second longest in Japan after the Shinano) and has a drainage area of (the largest in Japan). It is nicknamed Bandō Tarō (); ''Bandō'' is an obsolete alias of the Kantō ...
encompasses a large area of floodplain, for it has the largest drainage area in Japan of . The drainage areas covered by these rivers account for the alluvial lowland of the Kantō Plain.
A collection of plateaus constitute a large part of the plain. Among them are the Ōmiya,
Musashino,
Sagamino,
Jōsō, and
Shimōsa Plateaus. These large plateaus are divided into smaller ones by shallow river valleys. One of the common features of the plateaus is that their surfaces are covered with a thick layer of
loam
Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–sil ...
of volcanic origin. Volcanic ashes from surrounding volcanoes, Mounts
Asama,
Haruna, and
Akagi to the north and Mounts
Hakone
is a List of towns in Japan, town in Kanagawa Prefecture, Japan. , the town had a population of 11,293 and a population density of 122 persons per km². The total area of the town is . The town is a popular tourist destination due to its many o ...
and
Fuji Fuji may refer to:
Places China
* Fuji, Xiangcheng City (付集镇), town in Xiangcheng City, Henan
Japan
* Mount Fuji, the tallest mountain in Japan
* Fuji River
* Fuji, Saga, town in Saga Prefecture
* Fuji, Shizuoka, city in Shizuoka Prefec ...
to the southwest, are thought to have been deposited on these plateaus.
Among the plateaus, the Musashino Plateau has the largest stretch of land, extending from the western edge of
Ōme to the eastern edge of
Yamanote
and are traditional names for two areas of Tokyo, Japan. Yamanote refers to the affluent, upper-class areas of Tokyo west of the Imperial Palace.Iwanami Japanese dictionary, 6th Edition (2008), DVD version While citizens once considered it as ...
which borders the alluvial plains of the
Arakawa and
Sumida Rivers. Its elevation gradually declines from west to east, measuring 190 m at Ōme and 20 m at Yamanote.
Hills in the Kantō Plain stand on
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago.
The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...
strata and rise higher than surrounding plateaus, exemplified by the Sayama Hills and
Tama Hills, typically, undulating between 100 and 200 m above sea level. Hills located at the western edge of the Kantō Plain, the Hiki Hills, Koma Hills, Kusahana Hills, and Kaji Hills, also reach approximately above sea level.
What is noteworthy is the overall tilt of the plateaus and hills. In general, the whole area is slightly bent and forming a basin centered in the Tone River and Tokyo Bay. The ongoing process of
tectonic
Tectonics (; ) are the processes that control the structure and properties of the Earth's crust and its evolution through time. These include the processes of mountain building, the growth and behavior of the strong, old cores of continents ...
extension continues as the plain's central region gradually sinks.
The Kantō Plain witnessed its greatest devastation from an
earthquake on 1 September 1923, with a death toll calculated of 142,807.
Geology
Kanto Plain was formed by the Kanto basin-forming movement, which has continued since the
Neogene period
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...
. This Movement is that caused sedimentation in the center of the present-day Kanto Plain and uplift of the surrounding mountains. As a result, sediment from the surrounding mountains was deposited very thickly (the Tertiary layer reaches as high as 3,000 meters) and further uplifted to form many hills and plateaus. Large tectonic lines such as the eastern margin of the
Fossa Magna
Fossa Magna is a great rift lowland in Japan. It is often confused with Itoigawa-Shizuoka Tectonic Line. However, Itoigawa-Shizuoka Tectonic Line is a line; Fossa Magna is an area. Fossa Magna is Latin for "great crevasse". This name was given by ...
and the
Median Tectonic Line are thought to exist in the central part of the plain, but this thick accumulation of soft
sedimentary layers makes it difficult to find active faults that can cause earthquakes (faults exist in the base 3000m below the sedimentary layers). In addition, natural sediments such as sediment carried by rivers have been used to create land, and the terrain was almost the same as it is today in the
Late Jomon to Early
Yayoi Period
The started at the beginning of the Neolithic in Japan, continued through the Bronze Age, and towards its end crossed into the Iron Age.
Since the 1980s, scholars have argued that a period previously classified as a transition from the Jōmon p ...
(more than 3,000 years ago).
Climate
The climate of the Kanto Plain is temperate, with a Pacific Ocean side climate. Winters are cold and summers are hot. The further inland you go, the greater the temperature difference between summer and winter, and within a day. There are relatively many hours of sunshine, especially in the northern part of it.
Due to the influence of the
Black Current (warm current) flowing along the coast, the climate is mild, especially in the southern part of it.
In summer, rainfall is heavy due to the rainy season front caused by monsoon and typhoons are often seen. In addition, thunderclouds that form in the northern to western mountains areas before noon reach the plains in the early afternoon, often resulting in evening showers (thunderstorms). In years when Okhotsk anticyclone prevails, the winds from this anticyclone become northeasterly winds, and temperatures do not rise due to the cool air brought in by the Yamase, resulting in a cold summer.
In winter, the monsoon from 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 ...
is blocked by the Mikuni Mountains, and the moisture falls as snow along the mountains to the north, and the monsoon that has lost its moisture blows through the Kanto Plain as a strong gale carrying dry air (such as Akagi Orosi in
Gunma Prefecture
is a prefecture of Japan located in the Kantō region of Honshu. Gunma Prefecture has a population of 1,937,626 (1 October 2019) and has a geographic area of 6,362 km2 (2,456 sq mi). Gunma Prefecture borders Niigata Prefecture and Fukushima ...
, Tsukuba Orosi in
Ibaraki Prefecuture and Futaara Orosi). Snowfall has been decreasing year by year, but snow accumulation of around 10 - 20 cm is recorded several times during the winter.
Throughout the year, the entire Kanto Plain, especially the inland areas, are easily affected by
radiative cooling
In the study of heat transfer, radiative cooling is the process by which a body loses heat by thermal radiation. As Planck's law describes, every physical body spontaneously and continuously emits electromagnetic radiation.
Radiative cooling ha ...
due to clear skies and north winds, so the minimum temperature before sunrise can drop to about 5 degrees below zero in winter. Even on days when the temperature drops at dawn, the daytime temperature rises to about 7 to 10 degrees Celsius on sunny days, and on days with strong dry north winds, the sensory temperature is lower than the actual temperature.
The lowest temperatures in central Tokyo are higher than those in surrounding areas due to the heat island effect.
In addition,
Kumagaya
is a city located in Saitama Prefecture, Japan. , the city had an estimated population of 195,277 in 87,827 households and a population density of 1200 persons per km². The total area of the city is .
Geography
Kumagaya is one of the larges ...
tends to get hotter because of being inland, foehn phenomenon, which occurs when the wind in the sky above blows down after crossing the mountains on the north and west sides of the Kanto Plain, and the sea breeze that warms up while passing through central Tokyo.
References
{{DEFAULTSORT:Kanto Plain
Plains of Japan
Landforms of Tokyo
Landforms of Saitama Prefecture
Landforms of Kanagawa Prefecture
Landforms of Chiba Prefecture
Landforms of Gunma Prefecture
Landforms of Tochigi Prefecture
Landforms of Ibaraki Prefecture