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    What a way to start off the season! @UCSBMensSoccer tops No.5 Stanford 1-0 Friday. RECAP >>> http://t.co/gPhjHwqFP0 http://t.co/z7Z90RLG5D
    8 hours 22 min ago
  • UCSBgauchos twitter avatar
    The Gauchos start the 2015 season off in style, hold No. 8 Stanford scoreless to win 1-0. @UCSBMensSoccer first win over Stanford since 2004
    9 hours 32 min ago
  • UCSBgauchos twitter avatar
    Stanford trying desperately to get on the board but UCSB's backline can't be beat. Gauchos lead 1-0 with 5 minutes to go
    9 hours 39 min ago
  • UCSBgauchos twitter avatar
    Ahinga Selemani beats his defender to set up Geoffrey Acheampong beautifully in the box, but the lefty's shot goes wide of the post
    10 hours 5 min ago
  • UCSBgauchos twitter avatar
    Stanford with a pair of good chances with just under 30 minutes to go but UCSB still finds a way to keep them off the board and lead 1-0
    10 hours 11 min ago
  • UCSBgauchos twitter avatar
    .@UCSBMensSoccer leading No. 8 Stanford 1-0 at the half thanks to a goal by who else, Nick DePuy. Great first half for the Gauchos
    10 hours 39 min ago
  • UCSBgauchos twitter avatar
    GOAL! Seo-In Kim sends a cross far post and Nick DePuy heads it in to put the Gauchos up 1-0 with 3 minutes left in the half
    10 hours 47 min ago
  • UCSBgauchos twitter avatar
    Women's Soccer: San Jose State 1, UC Santa Barbara 1 (Final - 2OT) UCSB, San Jose State Battle to 1-1 Tie http://t.co/KolrGPE4AY
    10 hours 59 min ago
  • UCSBgauchos twitter avatar
    Big save by Vom Steeg to keep the game scoreless! 25 min left in 1st half @UCSBMensSoccer
    11 hours 11 min ago
  • UCSBgauchos twitter avatar
    Stanford has the advantage in the run of play through 10 minutes but it's still 0-0. @UCSBMensSoccer
    11 hours 20 min ago
  • UCSBgauchos twitter avatar
    WVB: UCSB Opens Season with Back-to-Back Sweeps! #GoGauchos http://t.co/yye1PtugDW
    11 hours 48 min ago
  • UCSBgauchos twitter avatar
    Heres UCSB's starting lineup against Stanford: Vom Steeg, Quezada, Strong, Backus, Jome, Espana, Feucht, Murphy, Acheampong, Selemani, DePuy
    11 hours 48 min ago
  • UCSBgauchos twitter avatar
    Don't miss @UCSBMensSoccer season opener against Stanford. Kickoff in 10 minutes!
    11 hours 56 min ago
  • UCSBgauchos twitter avatar
    @UCSBWomenSoccer ties San Jose St. 1-1 in home season opener behind early goal by Mallory Hromatko
    12 hours 5 min ago
  • UCSBgauchos twitter avatar
    RT @UCSB_Volleyball: Make that two sweeps on opening day! We topped UIW 3-0 and are now 2-0!… https://t.co/iybbM7N1tn
    12 hours 39 min ago

National Team of Scientists Predicts Continued Death of Forests In Southwestern U.S. Due to Problems Caused by Climate Change

Monday, December 13, 2010 - 16:00
Santa Barbara, CA

If current climate projections hold true, the forests of the Southwestern United States face a bleak future, with more severe –– and more frequent –– forest fires, higher tree death rates, more insect infestation, and weaker trees. The findings by university and government scientists are published in this week's issue of the Proceedings of the National Academy of Sciences (PNAS).

"Our study shows that regardless of rainfall going up or down, forests in the Southwest U.S. are very sensitive to temperature –– in fact, more sensitive than any forests in the country," said first author Park Williams, postdoctoral researcher in the Department of Geography at UC Santa Barbara. "Forests in the Southwest are most sensitive to higher temperatures in the spring and summer, and those are the months that have been warming the fastest in this area."

Past forest studies have shown that warmer temperatures are associated with wildfires and bark beetle outbreaks. "We found that up to 18 percent of forest area in the Southwest –– millions of acres –– has experienced mortality due to severe wildfires and bark beetle outbreaks in the last 20 years," said Williams.

Co-author Joel Michaelsen, a professor of geography at UCSB, said: "In order to carry out this research project, Park Williams assembled a very comprehensive data set of over 1,000 tree ring chronologies from all across the United States." Michaelsen is a dendroclimatologist –– a scientist who studies climate using analysis of tree rings.

"Instead of using the chronologies to reconstruct past climate patterns, as is usually done in dendroclimatic work, the relationships between growth and climate were used to study possible impacts of future climate change on forest health," said Michaelsen. "One noteworthy finding was that tree growth throughout the Southwestern U.S., while quite sensitive to precipitation variations, is also negatively impacted by warmer temperatures. This is an important result, because predictions of future warming in the region are considerably more certain than any predictions of precipitation change."

Researchers found that historic patterns of vegetation change, insect outbreaks, fire activity, runoff, and erosion dynamics show that landscapes often respond gradually to incremental changes in climate and land-use stressors until a threshold is reached, at which time there may be dramatic landscape changes, such as tree die-offs or episodes of broad-scale fire or erosion. They also found that the stressors that contribute to tree mortality tipping points can develop over landscape and even sub-continental scales.

Co-author Christopher Still, an associate professor of geography at UCSB, said: "These predicted large-scale changes in forest cover and composition (i.e., types of tree species present) will have large implications for everything from snowpack and the river flows that our society depends on, to the intensity and frequency of fires, to the visual appearance of these landscapes that drives much of the tourism in this region."

Added co-author Craig D. Allen of the U.S. Geological Survey: "Such big, fast changes in Southwest forest vegetation could have significant effects on a wide range of ecosystem goods and services, from watershed protection and timber supplies to biodiversity and recreation. These emerging vulnerabilities present increasingly clear challenges for managers of southwestern forests to develop strategies to mitigate or adapt to the coming changes, in order to sustain these forested ecosystems and their benefits into the future."

Forests help retain rainwater and keep it from flowing down mountains immediately, noted Williams in explaining the importance of forests to landscapes and rivers. "When forests disappear," he said, "water runs downhill more quickly and takes the upper layers of soil with it."

According to Williams, the erosion makes it harder for future generations of trees to establish themselves and makes it more difficult for people to capture storm water as it flows from the mountains. In addition, erosion increases the amount of sediment flowing in rivers and settling in lakes, and causes water to remain in the forest long after the rain.

The paper also points to the many implications of these changes for future management and use of Southwest forests.

The scientific article is part of a special PNAS feature edition called "Climate Change and Water in Southwestern North America."

 

 


 

 

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Top photo: Dead ponderosa pines in the Jemez Mountains at Bandelier National Monument. The research team explained that they died due to drought and probably infestations of bark beetles. This photo was shot in summer 2006.
Credit: Craig D. Allen
 

†† Middle photo: A Limber pine tree core from Mt. Crested Butte, southwestern Colorado. This portion of the core is 1 inch long and contains 47 annual growth rings. Skinnier rings formed during years of poor growth due to drought and/or bark beetles. Core collected by Park Williams and Chris Still.
Credit: Park Williams, UCSB
 

††† Bottom photo: Temperature and precipitation in the southwestern United States from 1896-2009 compared to the 1950-1979 average. Solid black lines represent the average location. Shaded areas represent the least extreme 50% of locations. Data from the PRISM group at Oregon State University.
Credit: Park Williams, UCSB

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