Tree Lines Are Migrating. Some Up, Some Down

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By Emily Gardner, Eos/AGU. 

Excerpt: Between 2000 and 2020, 42% of tree lines around the world crept upward, largely because of climate change. But 25% moved downhill, seemingly because of factors such as land use changes and wildfires. ...As the climate warms, tree lines are generally understood to move up, because regions that were previously too cold for trees to survive now have higher, more tree friendly temperatures. ...But new research, published in the International Journal of Applied Earth Observation and Geoinformation, paints a more complicated picture: Between 2000 and 2020, 42% of tree lines shifted up, true. But 25% of them actually moved downhill.... 

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