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Climate change. Increasing shrub abundance in the Arctic
1US Army Cold Regions Research & Engineering Laboratory-Alaska, PO Box 35170, Fort Wainwright, Alaska 99703, USA. msturm@ccrel.usace.army.mil
Nature
|June 1, 2001
Summary
Arctic warming is driving shrub expansion in Alaska. This widespread increase in shrub abundance over 50 years impacts energy balance, snow distribution, and carbon storage in the tundra ecosystem.
Area of Science:
- Arctic Ecology
- Climate Change Science
- Remote Sensing
Background:
- Alaskan Arctic warming has accelerated in recent decades.
- Increased shrub abundance is predicted to enhance tundra vegetation productivity.
- Evidence suggests a potential ongoing transition in Arctic landscapes.
Purpose of the Study:
- To present evidence for widespread shrub abundance increase in the Arctic.
- To analyze changes in shrub cover over the past 50 years.
- To understand the implications of shrub expansion on the Arctic ecosystem.
Main Methods:
- Comparison of historic and modern aerial photographs.
- Analysis of landscape changes over a 320 km transect.
- Assessment of shrub abundance trends.
Main Results:
- Demonstrated a widespread increase in shrub abundance across the Arctic landscape.
- Documented this expansion over more than 320 km during the past 50 years.
- Observed changes indicating a potential shift in tundra vegetation.
Conclusions:
- Shrub expansion significantly alters Arctic summer energy partitioning and winter snow distribution.
- Increased shrub cover may enhance carbon storage in a region currently considered a net carbon dioxide source.
- The findings highlight the dynamic response of Arctic ecosystems to climate warming.
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