Japan's Geographical and Climatic Background
Formation of the Island Arcs
The rich diversity of Japanese nature is shaped by both ancient and recent geological history.
The core of the Japanese archipelago formed 10 to 20 million years ago at the boundary between the Eurasian continent and the Pacific Ocean. The island arcs are convex toward the ocean and highly mountainous as results from back-arc basin formation, extensive volcanism, and tectonic uplift.
While the Japanese islands were repeatedly connected to the Asian continent during past ice ages, they were separated around 15,000 years ago.
Temperate Climates
The current climate and vegetation are predominantly temperate. However, they vary significantly due to the elongated chain of the islands, the steep topography, the seasonal monsoons from both the continent and the Pacific, and the surrounding ocean currents (see "Little BGSS Book").