ELEVATION OF TREELINES
· Average elevation of treeline is approximately 350 m higher in the Rocky Mountains study area (2151 m) than in the Coast Mountains study area (1808 m). This is although study area 82 is situated at higher latitude than 92, which makes the result even more significant.
· In both study areas the same pattern is evident: treeline elevation is highest on south-facing slopes, followed by west-facing, then east-facing slopes, and is lowest on north-facing slopes. However, the difference in treeline elevation between north- and south-facing slopes is higher in 92 (ca. 200 m difference) than in 82 (ca. 100 m difference). This is likely due to the thickness and duration of snow cover in 92, which has a higher impact on north-facing slopes, as snow melts very slowly here, not receiving a lot of solar radiation.
· It is also evident that west-facing slopes can support a higher treeline than east-facing slopes. This is likely due to the lagging nature of temperature development over the day: it is cold at sunrise in the morning, and warm at sunset in the evening.
Average elevation of treeline depending on aspect and study area:
|
|
study area 82: Rocky Mtns |
study area 92: Coast Mtns |
|
north |
2084 |
1700 |
|
east |
2143 |
1798 |
|
south |
2193 |
1898 |
|
west |
2176 |
1833 |
