- If a whole forest disappears, new research shows, this has ricocheting effects in the atmosphere that affect vegetation on the other side of the country.
- The Pacific Southwest region, which covers most of California, has the smallest total area of tree cover. But removing those trees had the biggest influence on growing conditions nationally, by reducing vegetation in the Eastern U.S.
- Forest loss is disrupting or changing the flow patterns in the atmosphere that is leading to a slightly different summertime climate in the eastern part of the country.
May 16, 2018 University of Washington Read full ScienceDaily article here
Large swaths of U.S. forests are vulnerable to drought, forest fires and disease. Many local impacts of forest loss are well known: drier soils, stronger winds, increased erosion, loss of shade and habitat. But if a whole forest disappears, new research shows, this has ricocheting effects in the atmosphere that can affect vegetation on the other side of the country.
….forest die-offs in specific regions of the United States can influence plant growth in other parts of the country. The largest impacts seen were from losing forest cover in California, a region that is currently experiencing dramatic tree mortality.
“These smaller areas of forest can have continental-scale impacts, and we really need to be considering this when we’re thinking about ecological changes,” said first author Abigail Swann, a UW assistant professor of atmospheric sciences and of biology. Such far-off effects are accepted in the atmospheric sciences community, Swann said, but the idea is only beginning to be accepted by ecologists….
“Forest loss is disrupting or changing the flow patterns in the atmosphere that is leading to a slightly different summertime climate in the eastern part of the country,” Swann said. “It’s very analogous to El Niño or ‘the blob,’ something that’s occurring that causes the atmosphere to move around, which causes these warmer or cooler conditions, or wetter and drier conditions, somewhere else.”…
…The study suggests that current forest loss in Western regions is big enough to trigger changes in plant growth, though it might not be possible to detect these small changes over large areas of the country…
Abigail L S Swann, Marysa M Laguë, Elizabeth S Garcia, Jason P Field, David D Breshears, David J P Moore, Scott R Saleska, Scott C Stark, Juan Camilo Villegas, Darin J Law, David M Minor. Continental-scale consequences of tree die-offs in North America: identifying where forest loss matters most. Environmental Research Letters, 2018; 13 (5): 055014 DOI: 10.1088/1748-9326/aaba0f