A temperate biome is the climate zone in the mid-latitudes (between about 25 and 60 degrees) of both the northern and southern hemispheres that is characterized by moderate temperatures and four distinct seasons. A biome is a relatively large division of the biosphere that has a distinct climate, particularly with regard to average annual precipitation and temperature, and that contains characteristic types of organisms, especially vegetation.
This contrasts with the tropical biome, which is near the equator and is warm, wet and features great biodiversity, and the boreal biomes, which are at the high latitudes and are cold, dry and have the least biodiversity.
The temperate biomes are mainly terrestrial and are characterized primarily by forests, along with grasslands and shrub lands. Water bodies, such as lakes, wetlands and rivers, cover only a small fraction of the total area. Temperate biome forests, which account for about a quarter of the earth's forest area, are dominated by deciduous or coniferous trees or mixed forests containing both types, and have moderate biodiversity. These forests also include temperate rainforests in very wet coastal areas.
Temperate grasslands constitute a much smaller portion of the temperate biome, with the percentages varying greatly according to the region. They have historically covered vast areas most notably the Eurasian steppes, the North American prairies, and the Argentine pampas. Deserts account for only a small portion of the temperate biome's total area and are instead mostly located in the subtropical and tropical regions.
The temperate biomes include adjacent coastal areas extending to the edge of the continental shelf and somewhat beyond. Such areas differ from the land-based biomes with regard to temperature moderation, seasonal variations and precipitation patterns due to the influence of the ocean and contain diverse habitats including rocky and sandy shores, marshes, estuaries, and seagrass and kelp beds. The open ocean beyond is classified vertically according to its depth.