Temperate Rainforest

Temperate Rainforest

For temperate rain forests of North America, Alaback's definition is widely recognized:

1. Annual precipitation over 1400 mm
2. Mean annual temperature between 4 and 12 degrees Celsius. (39 and 54 degrees Fahrenheit)

However, required annual precipitation depends on factors such as distribution of rainfall over the year, temperatures over the year and fog presence, and definitions in other countries differ considerably. For example, Australian definitions are ecological-structural rather than climatic:

Plant in temperate rainforest are all predominantly coniferous, sometimes with an understory of broadleaved trees and shrubs. The conifer dominance is a consequence of two climatic factors: Although the region has high total precipitation, most occurs during the winter, and summers are relatively dry. During summer, moisture stress reduces the amount of photosynthesis possible especially for broadleaved trees. However, winters are very mild, and coniferous species are capable to carry on substantial amounts of their yearly photosynthesis during fall, winter and spring.