Editing Taiga (section)

===Precipitation===
The taiga experiences relatively low [[Precipitation (meteorology)|precipitation]] throughout the year (generally {{cvt|200|–|750|mm|in}} annually, {{cvt|1,000|mm|in}} in some areas), primarily as [[rain]] during the summer months, but also as [[snow]] or [[fog]]. Snow may remain on the ground for as long as nine months in the northernmost extensions of the taiga biome.<ref>A.P. Sayre, ''Taiga'', (New York: Twenty-First Century Books, 1994) 16.</ref>

The fog, especially predominant in low-lying areas during and after the thawing of frozen Arctic seas, stops sunshine from getting through to plants even during the long summer days. As [[evaporation]] is consequently low for most of the year, annual precipitation exceeds evaporation, and is sufficient to sustain the dense vegetation growth including large trees. This explains the striking difference in biomass per square metre between the Taiga and the [[Steppe]] biomes, (in warmer climates), where evapotranspiration exceeds precipitation, restricting vegetation to mostly grasses.

[[File:Skjomtinden & Kongsbakktinden from Bogen, 2010 September.JPG|thumb|Late September in the [[fjord]]s near [[Narvik]], Norway. This oceanic part of the forest can see more than {{cvt|1,000|mm|in}} precipitation annually and has warmer winters than the vast inland taiga.]]

In general, taiga grows to the south of the {{cvt|10|C|F}} July [[Isotherm (contour line)|isotherm]], occasionally as far north as the {{cvt|9|C|F}} July isotherm,<ref>Arno & Hammerly 1984, Arno ''et al.'' 1995</ref> with the southern limit more variable. Depending on rainfall, and taiga may be replaced by [[forest steppe]] south of the {{cvt|15|C|F}} July isotherm where rainfall is very low, but more typically extends south to the {{cvt|18|C|F}} July isotherm, and locally where rainfall is higher, such as in eastern [[Siberia]] and adjacent [[Outer Manchuria]], south to the {{cvt|20|C|F}} July isotherm.

In these warmer areas the taiga has higher species diversity, with more warmth-loving species such as [[Korean pine]], [[Jezo spruce]], and [[Manchurian fir]], and merges gradually into [[Temperate broadleaf and mixed forests|mixed temperate forest]] or, more locally (on the [[Pacific Ocean]] coasts of North America and Asia), into coniferous [[temperate rainforest]]s where oak and hornbeam appear and join the conifers, birch and [[Populus tremula]].