All Japanese islands are predominantly of volcanic origin and very mountainous. The northernmost of the four main islands is Hokkaido. Mountain ranges penetrate it from the north (Kitami Mountains), through the central Ishikari with volcanoes exceeding 2000 mk to the south (Hidaka). The third mountain range fills the peninsula in the west and is separated from the others by a lowland flowed by Japan’s longest river, Ishikari.
To the south of Hokkaido, across the Tsugari Strait, lies Honshu – the largest and most populated of all the islands. From the north, the Óu mountain range stretches through the center, along the Pacific coast the Kitakami ridge – a continuation of the mountain range from the island of Hokkaido. The central part of Honshu is filled with a complex system of mountain ranges collectively called the Japanese Alps. Near the southern coast west of Tokyo rises the lone volcano and Japan’s highest mountain, Fuji (3776 m). To the southeast of the center of the Japanese Alps, Japan’s largest plain, Kanto, stretches over an area of approximately 13,000 km2. In its southern part, by Tokyo Bay, lies the capital city of Tokyo.
To the west of the central mountain system lies the smaller Nobi Plain, which surrounds the city of Nagoya on the coast to the north of the deep-running Ise Bay. Just west of here is Japan’s largest lake, Biwa. Most of the narrowing island to the west is filled by the Čugoku mountain range. A narrow coastal plain on its southern side is bordered by the so-called Inner Sea with hundreds of small islands, separating western Honshu from the island of Shikoku with mountains reaching almost 2000 m. To the south of Lake Biwa extends the wide and mountainous Kii Peninsula. Japan’s second largest conurbation, Osaka-Kyoto-Kobe, lies on its west coast by the Osaka Bay.
The westernmost island, Kyushu with a very rugged west coast, is separated from Honshu in the north by the Simonoseki Strait and in the east from Shikoku by the Bungo Strait. The volcanic massifs in the center of the island are already lower, the highest peaks exceed 1700 m. To the south of Kyushu, a number of active volcanoes protrude from the sea.
According to Prozipcodes.com, Japan is a seismically very active region, affected by dozens of earthquakes a year and frequent volcanic eruptions. At least 60 active volcanoes are recorded. The most active zone is in southern Kyushu, followed by northern and central Honshu. Devastating catastrophic earthquakes occur on average once every five years.
There are many rivers on the islands, but they are mostly short, predatory streams draining relatively small areas. In the spring, they are fed by melting snow and firn from the mountains, and in the summer by monsoon rains. Flooding is a common phenomenon in low-lying areas.
Japan has a monsoon-type climate that varies widely with latitude from cool in the north to subtropical in the south. In winter, northwesterly winds blow from continental Asia and cause sub-freezing temperatures. The cold air becomes moist over the Sea of Japan and dense clouds form, bringing heavy snowfall to the entire west coast and mountains. In the east, winters are drier with less cloud cover. A narrow strip along the southeast coast is also warmed by the warm Kuro-shio current. Average winter temperatures are higher in the south, which is why farmers in Kyushu can also harvest winter crops.
In late March, as the Asian mainland warms, the winds begin to veer to the south and east, and sometime around mid-June or early July, a several-week period of torrential downpours known as the baiu, “plum” rains sets in. Summers are exceptionally hot and humid with frequent coastal fogs, especially in the Inubo Bay area in the southeast, where the cold Oya-shio current meets the warm Kuro-shio current. In the north, the summers are cooler and the transition periods are shorter. At the turn of August and September, the air circulation changes again and there are violent storms, typhoons accompanied by heavy rains. Typhoons, especially in the south, can have disastrous effects and are known to have destroyed most of the rice crop. It starts to get really cold from October. Due to the mountainous terrain and close proximity to the sea, rainfall is abundant throughout the year, and the highest elevations in Honshu and Hokkaido are permanently covered with snow. The whole of Japan receives more than 1000 mm of precipitation, while the central Japanese Alps receive more than 2500 mm.
Flora and fauna
Approximately 2/3 of Japan’s territory is covered by forests, and in several places even the original forest-like vegetation has been preserved. Bamboo forests extending along their northern edge as far as Tokyo provide useful timber and bamboo shoots are used as vegetables. Sakura cherry trees, so prized for their flowers, are planted all over the country and also grow wild in the mountains. There are five vegetation zones in Japan. Ryukyu, the Bonin Archipelago and the Volcano Islands, the southernmost region extending to the Tropic of Cancer, is covered in subtropical rainforests, in which we find camphor trees, tree ferns and mulberry trees. The second vegetation formation of the subtropical zone begins on the slopes of the southwestern islands with more than 2000-year-old Japanese cedars. It stretches from the island of Yakushima through Kyushu, where it reaches a height of 1,000 meters to beyond central Honshu, where it descends to sea level.
Deciduous and mixed forests make up the third zone, which reaches up to 2,000 meters on Shikoku. Typical trees are beech, birch, kacura and oak. The fourth zone, consisting mainly of coniferous Nordic forests, begins in places where the average annual temperature drops below 6 °C, i.e. mainly in the mountains of central Honshu and in the southwest of Hokkaido. Among the trees of the Nordic forests we can find Sakhalin spruce, Sakhalin fir and blue fir. At the highest altitudes of the mountains, these forests pass into the fifth zone, characterized by scrub, creeping pine and alpine vegetation.
A wide variety of wildlife lives in the forested mountains inland. From wild pigs to bears and wild dogs hunting hares, deer and antelopes to monkeys. The Japanese macaque represents the most northerly distribution of monkeys in the world. There are also many species of lizards, turtles and snakes, including poisonous ones such as sea pythons and species of habu and mummy.
The Japanese kingfisher living in Honshu and Kyushu can reach a length of more than 1.5 meters. Japan is also very rich in various types of insects and freshwater fish. Birds are widespread throughout the territory, only singing birds, there are about 150 species. Typical aquatic species are albatrosses, petrels and cormorants. The waters east of Cape Inubo are among the richest fishing grounds in the world, especially for cod, salmon and crustaceans.