The evidence for shrub expansion in Northern Alaska and the Pan‐Arctic

  title={The evidence for shrub expansion in Northern Alaska and the Pan‐Arctic},
  author={Ken D. Tape and Matthew Sturm and Charles H. Racine},
  journal={Global Change Biology},
One expected response to climate warming in the Arctic is an increase in the abundance and extent of shrubs in tundra areas. Repeat photography shows that there has been an increase in shrub cover over the past 50 years in northern Alaska. Using 202 pairs of old and new oblique aerial photographs, we have found that across this region spanning 620 km east to west and 350 km north to south, alder, willow, and dwarf birch have been increasing, with the change most easily detected on hill slopes… 

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