Taiga (Boreal Forest) Weather and Climate

1. Taiga (Boreal Forest)Weather and Climate By: Evan Gilman (Other Taiga PowerPoint's By: Drew, Robert, and Vincent)

2. Weather and Climate The taiga is a biome of extremes; extremes in temperature, extremes in humidity, extremes in precipitation, and extremes in daylight hours. However, the taiga has remarkably little wind. Overall though, the taiga has giant fluctuations in weather and climate like no other biome.

3. Weather and Climate Temperature • Temperatures range from -90°F to 104°F. The average temperature is 32°F. • The summer (average 50°F or more) lasts 1-3 months and is always less than 4 months. In much of taiga, 64°F would be the average temperature in the summer. • The winter (average 32°F or less) lasts 5-7 months. In much of taiga, -4°F would be the average temperature in the winter. • There are 50 to 100 frost-free days per year.

4. Weather and Climate Precipitation • Taiga has relatively low precipitation throughout the year (generally 8-30 inches annually, 40 inches in some areas), mostly as rain during the summer and snow in the winter. Mean annual precipitation is 15 to 20 inches. • Much of the taiga climate is considered humid. However, large areas in western Canada and Siberia receive very little precipitation and fall into the sub humid or semiarid climate type. Precipitation exceeds evaporation, and that helps sustain the dense vegetation growth. • Snow may stay on the ground for as long as 9 months in the northernmost extensions of the taiga.

5. Weather and Climate Daylight • The taiga's high latitudes mean that the sun does not rise far above the horizon, and less solar energy is received than further south. • But the high latitude also ensures very long summer days, as the sun stays above the horizon nearly 20 hours each day. The short taiga summer brings long, warm periods of daylight that lead to rapid plant growth. • There are around 6 hours of daylight occurring in the dark winters, depending on latitude. • The area of the taiga inside the Arctic Circle have midnight sun in mid-summer and polar night in mid-winter.

6. Weather and Climate Climate Change • There is general consensus that climatic changes will have the greatest impact on the taiga, as its unique adaption makes them more sensitive to temperature fluctuations than any other biome. Even a slight increase in mean annual temperature is enough to affect many species' growth and regeneration. • As climate warms, conditions suitable for the growth of many taiga species are likely to shift dramatically, and the trees' ecological niches may move northward ten times faster than the trees themselves can migrate. • Overall, the taiga is likely to decrease in area, biomass, and carbon stock, with a significant disruption at its southern boundary. Taken all together, these impacts could add up to an alarming 65 percent loss of taiga.