Moisture Shortfall, Heat Threaten Southwestern US Forests

By John Upton

Pinecone-littered forests draped over tens of millions of acres of mountaintops through the American Southwest are in danger of being scorched out of existence by global warming.

It’s not just rising heat that threatens to put a meteorological flamethrower to lush montane swaths of Arizona and New Mexico better known for low-altitude cacti and desert plains. A fire-wielding threat also comes from a rise in vapor pressure deficit, or VPD — a parching force linked to climate change that rises as heat increases or as humidity decreases.


photo credit: <a href="">James Marvin Phelps</a> via <a href="">photopin</a> <a href="">cc</a>