Japan is an arc-shaped archipelago that stretches a long way from northeast to southwest. The four islands Hokkaido, Honshu, Shikoku and Kyusyu are the main islands making up the archipelago, and, if the southwestern islands centered around Okinawa are included, the length of the archipelago comes to 3,500 km. Based on its chikei, the Japan Islands are thought to have been formed by the merging of the northeast arc and the southwest arc, taking the approximate middle of Honshu as the boundary between the two. Sixty-one percent of the land is precipitous mountains covered with forests. Meanwhile, the flat areas, including the open country and mountain valleys where people can live, amount to only 24 percent. Sixty-five percent of the population is centered there. They are therefore blessed by beautiful mountains and lush greenery, but, on the other hand, the population density on the land that is habitable is among the highest in the world.
Except their the southwestern islands belonging to the subtropical zone, the Japan Islands belong to the temperate zone. They are located on the eastern edge of the Asian Continent and the western edge of the Pacific, so their summers, with seasonal southeast winds that blow in from the high pressure of the Pacific Ocean, have high temperature and humidity; and its winters, with the seasonal northwest winds blowing under the influence of Siberian high pressure, are cold. The above graph shows the difference in temperature between this heat and cold compared with Los Angels, which is at the same latitude as Tokyo. As it is indicated by this great changes of temperature, the special characteristics of kiko in Japan are clearly distinguished seasons and having the highest precipitation rate even among the other temperate zone countries. With these characteristics of the seasons, the Japanese, who are an agricultural people, have developed a keen sense of the seasons in relation to agriculture; that has influenced their aesthetic senses and has shaped their sensibility.
When a subtropical low pressure zone in the South Pacific develops, and start to hit Japan, it is called taifu. Every year from summer into autumn, taifu cause the Japan Islands great storm and flood damage. 80% of storm and flood damage in Japan is caused by taifu. There are destruction of buildings and reduction of crops from storm damage and breakdown of power lines from the salt winds, and there is damage from torrential rain such as floods, things being swept away, mudslides, landslides, and rock slides. Compared to hurricanes in America, the main characteristic of taifu damage in Japan is probably that there are mud and landslides that occur because of its geography featuring the precipitous mountains. Due to taifu, every year a number of people die, houses are destroyed, and traffic cur off.
The Japanese humorously express the ranking of things to be feared in this world as: "earthquakes, thunder, fires, fathers." Jishin produce so much damage and occur so frequently in every region of the Japan Islands that they are ranked as the number one phenomenon to be feared. When one looks at jishin on a global scale, the Japan Islands are part of the Pacific rim jishin belt. In the catastrophe of the Great Kanto Earthquake of 1923, about 90,000 people died from houses collapsing and from fires, and recently Okushiri Island was almost completely destroyed overnight by a jishin off the southwest coast of Hokkaido. In order to minimize the damage of such frequently occurring Jishin, research in jishin forecasting is advancing in Japan and the world's highest safety standards are established for buildings.
Kazan regions run along the Japan Islands, almost overlaying the earthquake belts, and together they form the world's most active earthquake and kazan region. Kazan in some regions occasionally have major eruptions causing damage at the foot of the mountains. The eruptions of Mt. Unzen fugen in Nagasaki Prefecture that have continued since 1991 have assaulted the surrounding villages with lava and earth and rock flows and the villages have fallen into a crisis of total destruction. Mt. Fuji too has had large eruptions a number of times in the past, and it is believed to erupt again.
These kazan not only cause damage to the Japan Islands, they also cause hot springs to gush out in various parts of the country and so are conducive to the good health of the people. Known for a long time to be effective against various illnesses, there are hot springs all over Japan.
Sixty-seven percent of the land in Japan is shinrin. The reason why there are so many shinrin is, first of all, that there is a lot of precipitation that prepares the conditions for nurturing shinrin. The average precipitation per day in Tokyo is 11 mm and in Niigata in the snow country it is 8 mm, but it is no more than half in the other temperate zone countries. The fact that mountainous regions comprise 61% of the land is a further reason why shinrin areas are plentiful. Besides, in the ice age the Japan Islands were not covered with glaciers, so it is rich in varieties of plants by Comparison with the temperate zones of the European and American continents. In addition, the management of shinrin, such as reforestation, is in progress. Under these kinds of conditions, Japan has nurtured its culture of wood. The Horyuji, a temple in Nara, is the world's oldest wooden structure.
Japan is an island nation surrounded by umi. And it is at such a location, where the distance from the Asian Continent was neither too far to accept the culture from it nor too close to be invaded, that it was suitable for Japan to create peculiar cultural realm. On the Pacific side, the warm Black Current flows from the south and the Kurile Current comes down from the north, meeting almost at the center of the archipelago, forming the world's three "big catch" fishing spots. In the spring, ice floes in large quantities drift from the Sea of Okhotsk to the northeast coast of Hokkaido. The sea of Okinawa, on the south of Japan, is famous worldwide for the clear water and one of the world's most noted coral reefs.
"The train came out of the long tunnel of a border area into the snow country." That is the famous opening of Nobel Prize-winning novelist KAWABATA Yasunari's masterpiece "Snow Country". This phrase accurately indicates a geographical feature of Japan. In winter, a chilly seasonal wind blows from Siberia, striking the mountain range that runs through the central part of Honshu from the northeast to the southwest and causing heavy snowfall on the Japan Sea side. There is not much snowfall on the Pacific Ocean side of the mountain range. Thus, when one comes out of the tunnel from the Pacific side to the Japan Sea side, the yuki-guni with snow piling high dramatically appears. The term yuki-guni therefore indicates the regions on the Japan Sea side of Honshu, the Tohoku area and all of Hokkaido.
Because the Japan Islands are 61% composed of steep mountainous regions and have a lot of rainfall, naturally there are many of both kawa and mizuumi. Reflecting those geographical features, kawa have rapid currents and abundant amounts of water. In addition, forests in the mountainous regions preserve water well: because this turns into underground water, there is a lot of spring water and clean water flows into kawa and mizuumi. Mashu Lake, a lake in Hokkaido, was formerly the world's clearest mizuumi.
However, with large scale dam and levee constructions being undertaken on rivers throughout the country for flood control, nature has been destructed and polluted by construction drainage water. Currently, the Japanese people have begun to reconsider the beauty of nature and whether it can coexist with the security of the people.