A Pacific Island CountryJapan is an island country forming an arc inthe Pacific Ocean to the east of the Asiancontinent. The land comprises four largeislands named (in decreasing order of size)Honshu, Hokkaido, Kyushu, and Shikoku,together with many smaller islands. ThePacific Ocean lies to the east while the Sea ofJapan and the East China Sea separateJapan from the Asian continent.

In terms of latitude, Japan coincidesapproximately with the Mediterranean Seaand with the city of Los Angeles in NorthAmerica. Paris and London have latitudessomewhat to the north of the northern tip ofHokkaido.

Japan’s total land area is about 378,000square kilometers. It is thus approximately thesame size as Germany, Finland, Vietnam, orMalaysia. It is only 1/25 the size of the UnitedStates and is smaller than the state ofCalifornia.

Japan’s coastline is quite varied. In someplaces, such as Kujukurihama in ChibaPrefecture, there are long sandy beachescontinuing fairly straight and uninterrrupted for60 kilometers or so, while the coast ofNagasaki Prefecture is an example of an area

Geography

Web Japanhttp://web-japan.org/

GEOGRAPHY AND CLIMATEA country of diverse topography and climate

characterized by peninsulas and inlets andoffshore islands (like the Goto archipelagoand the islands of Tsushima and Iki, whichare part of that prefecture). There are alsoaccidented areas of the coast with manyinlets and steep cliffs caused by thesubmersion of part of the former coastline dueto changes in the Earth’s crust.

A warm ocean current known as theKuroshio (or Japan Current) flowsnortheastward along the southern part of theJapanese archipelago, and a branch of it,known as the Tsushima Current, flows intothe Sea of Japan along the west side of thecountry. From the north, a cold current knownas the Oyashio (or Chishima Current) flowssouth along Japan’s east coast, and a branchof it, called the Liman Current, enters the Seaof Japan from the north. The mixing of thesewarm and cold currents helps produceabundant fish resources in waters near Japan.

A Land of hot springs and attractivescenaryAbout three-fourths of Japan’s land surface ismountainous. The Chubu Region of centralHonshu is known as “the roof of Japan” andhas many mountains which are more than3,000 meters high.

Japan’s highest mountain is Mt. Fuji(3,776 meters) on the border of Yamanashiand Shizuoka prefectures. Japan’s second-highest peak is Kitadake in YamanashiPrefecture, at 3,193 meters, while its jointthird-highest peaks are Okuhotakadake at3,190 meters, on the border between Naganoand Gifu prefectures, and Ainodake at 3,190meters, on the border between Yamanashiand Shizuoka prefectures.

Mt. FujiJapan’s highest peak, Mt. Fuji, is seen here from Lake Kawaguchi in April. It remains covered in snow until June.

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mountains of the Chubu region throughNiigata Prefecture to the Sea of Japan.Second in length is the Tone River, whichflows through the Kanto Plain to the PacificOcean, and third in length is the Ishikari Riverin Hokkaido, at about 268 kilometers.

The many rivers descending frommountainous areas have done much to moldJapan’s topography, creating large and smallvalleys and basins and producing fan-shapeddeltas near the points where they flow into thesea. Most of the country’s plains are small.The largest is the Kanto Plain, which includesparts of Tochigi, Ibaraki, Gunma, Saitama,Chiba, Tokyo, and Kanagawa prefectures.Other relatively large areas of flat land are theEchigo Plain (Niigata Prefecture), the IshikariPlain (Hokkaido), and the Nobi Plain (Aichiand Gifu prefectures).

A major feature of Japan’s climate is theclear-cut temperature changes between thefour seasons. From north to south, Japancovers a range of latitude of some 25 degreesand is influenced in the winter by seasonalwinds blowing from Siberia and in thesummer by seasonal winds blowing from thePacific Ocean. In spite of its rather small area,Japan is characterized by four differentclimatic patterns.

Hokkaido, with a subarctic weatherpattern, has a yearly average temperature of9.45 degrees centigrade and receives anaverage annual precipitation of about 1,205millimeters. The Pacific Ocean side of Japan,from the Tohoku region of northern Honshu toKyushu, belongs to the temperate zone, andits summers are hot, influenced by seasonalwinds from the Pacific. The side of thecountry which faces the Sea of Japan has aclimate with much rain and snow, producedwhen cold, moisture-bearing seasonal windsfrom the continent are stopped in theiradvance by the Central Alps and othermountains which run along Japan’s centerlike a backbone. The southwestern islands ofOkinawa Prefecture belong to the subtropicalclimate zone and have a yearly averagetemperate of over 22 degrees, while receivingover 2,000 millimeters of precipitation.

As it is situated along the circum-Pacificvolcanic belt, Japan has several volcanicregions—usually considered to number seven—from the far north to the far south. Of thetotal number of volcanoes, approximately 110are active, including Mt. Mihara on IzuOshima island, Mt. Asama on the borderbetween Nagano and Gunma Prefectures,and Mt. Aso in Kumamoto Prefecture. Japanhas almost 1/10 of the world’s approximately1,500 active volcanoes, even though it hasonly about l/400 of the world’s land area. Mt.Fuji, which has been dormant since its lasteruption in 1707, is by no means incapable oferupting again in our lifetimes.

Though volcanoes can cause great harmthrough large eruptions, they also contributean incalculable tourist resource. Touristicareas such as Nikko, Hakone, and the IzuPeninsula, for example, are famous for theirhot springs and attractive scenery of volcanicmountains.

As all these volcanoes attest, the Earth’scrust beneath the Japanese archipelago isunstable and full of energy. Thus Japan isamong those countries most likely to sufferfrom earthquakes. Every year there areapproximately 1,000 earthquakes which arestrong enough to be felt. In January 1995, theGreat Hanshin-Awaji Earthquake killed over6,000 people, injured over 40,000, and left200,000 homeless. An earthquake in NiigataPrefecture in October 2004 left over 60people dead and more than 4,800 injured. InMarch 2011, a magnitude 9 earthquake wasrecorded off the coast of Sanriku (Tohoku) inthe Pacific Ocean, and the ensuing tsunami,about 10m high in places, hit the coast acrossa vast region from Tohoku to Kanto. Thenumber of dead and missing after theearthquake and tsunami reached nearly22,000.

Fast-Flowing RiversMountainous Japan is blessed with manyrivers. Most of Japan’s rivers flow very fast,their waters reaching the ocean not long afterleaving mountain valleys and basins. Anexample of the “steepness” of river flows isthe Kurobe River, which joins the Sea ofJapan after flowing about 85 kilometers fromits source in the Japan Alps at an altitude ofover 2,900 meters.

Japan’s longest river is the Shinano River,which flows 367 kilometers from the

Climate

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Spring (March, April, May)When winter nears its end, the cold seasonalwinds blowing from the continent becomeweaker and more intermittent. At this time,low pressure air masses originating in Chinaenter the Sea of Japan; these give rise tostrong, warm southerly winds which traveltoward this low-pressure zone from thePacific Ocean. The first of these winds iscalled haru ichiban. While it announces thewarmth of the coming spring, it sometimescauses avalanches and, crossing themountains to the side of the country facingthe Sea of Japan, it is at times responsible forexceptionally hot and dry weather and caneven become the cause of large fires.

In early spring, plum blossoms start tobloom, followed by peach blossoms. Betweenlate March and the end of April, the cherryblossoms so beloved by the Japanese peoplebegin to bloom, starting in southern Japanand slowly spreading north.

Summer (June, July, August)Before the arrival of real summerlike weather,Japan has a damp rainy season known astsuyu. From May until July, there is a high-pressure mass of cold air above the Sea ofOkhotsk to the north of Japan, while over thePacific Ocean there develops a high-pressuremass of warm, moist air. Along the line wherethese cold and warm air masses meet, knownas the baiu zensen, or “rainy season front,”there often develop areas of low-pressurewarm air. Thus the baiu zensen, whichextends from southern China over theJapanese archipelago, causes prolongedperiods of continuous rainfall.

After the middle of July, high-pressure airmasses over the Pacific Ocean becomepredominant and the rainy season comes toan end as the baiu zensen is pushednorthward. Seasonal winds from the PacificOcean bring warm, moist air to Japan, andthe country has hot summer weather withmany days when temperatures rise to morethan 30 degrees centigrade.

Cherry blossomsCherry blossoms—the symbol of spring in Japan.

Firework displaysFirework displays like this one are an essential part of the Japanese summer.

Autumn (September, October, November)From the end of summer through September,Japan is often struck by typhoons. Typhoonsoriginate from large masses of tropical low-pressure air in the North Pacific between thelatitudes of approximately 5 and 20 degrees,and are the same phenomenon as hurricanesand cyclones in other parts of the world.When a typhoon begins to take shape, itgradually moves north. Every year, during thisperiod, around 25 typhoons form, of which onthe average about 4 reach Japan, sometimescausing great destruction.

After the middle or latter part of October,Japan enjoys generally clear weather; it isneither hot nor cold. The country also enjoysespecially fine weather at the beginning ofNovember. Many of the trees take on brightautumn colors, making this time of the year,together with the time of new greenery in thespring, a truly beautiful season.

Winter (December, January, February)Toward the end of November, cold seasonalwinds begin blowing over Japan from thecontinent. These northwesterly winds pick upmoisture over the Sea of Japan and dropmuch of this moisture in the form of rain andsnow on the western side of Japan as theyare impeded in their eastern advance by theridge of mountains that runs through thecentral part of the country. The Hokurikuregion (Fukui, Ishikawa, Toyama, and Niigataprefectures), which faces the Sea of Japan

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Autumn leaves Colorful foliage is the symbol of autumn throughout Japan.

Cherry blossomsCherry blossoms—the symbol of spring in Japan.

Shirakawa-go in WinterThe gassho-zukuri style farmhouses of Shirakawa village in Gifu Prefecture were inscribed on the UNESCO World Heritage List in 1995. (Photo courtesy of AFLO)

and is separated from other regions of Japanby high mountains, is known for its deepsnows.

By contrast, the Pacific side of the countryenjoys generally clear skies during the winterseason. In Tokyo, despite the fair skies,winter temperatures average around 5degrees, a difference of 25 degrees fromsummer temperatures of 30 degrees or more.

The islands of Okinawa Prefecture in thefar southwest have a subtropical climate withless marked temperature differences betweenthe seasons. Winter temperatures there aremuch more moderate than in other parts ofthe country.

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