White spruce trees are encroaching on Alaskan tundra previously too harsh for their growth, exacerbated by the Arctic warming rate which is significantly higher than the global average.
This 'Arctic greening' alters the local albedo effect, where darker tree areas absorb more sunlight, contributing to permafrost thawing and the potential release of greenhouse gases.
Research indicates that decreased sea ice leads to more evaporation and snow, which aids young spruce survival, facilitating the northward spread of boreal forests.
Key quote:
"Once it gets to be about waist high, it's going to live. It's the little babies that don't survive."
— Roman Dial, ecologist at Alaska Pacific University
Why this matters:
Increased tree coverage in the Arctic could intensify warming trends and contribute to the escalating release of greenhouse gases from permafrost.
