Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A look back suggests a sobering future of wildfire dangers in US west

15.02.2012
University of Oregon-led research team urge a retooling of thought on fire-management practices

The American West has seen a recent increase in large wildfires due to droughts, the build-up of combustible fuel, or biomass, in forests, a spread of fire-prone species and increased tree mortality from insects and heat.

In a paper appearing online Feb. 14 in the Proceedings of the National Academy of Sciences, a 12-member research team warns that these conditions may be "a perfect storm" for more fires.

While grazing and fire suppression have kept incidents of wildfires unusually low for most of the last century, the amounts of combustible biomass, temperatures and drought are all rising. "Consequently, a fire deficit now exists and has been growing throughout the 20th century, pushing fire regimes into disequilibrium with climate," the team concludes.

"The last two centuries have seen dramatic changes in wildfire across the American West, with a peak in wildfires in the 1800s giving way to much less burning over the past 100 years," said lead author Jennifer R. Marlon, now a National Science Foundation Earth Science Postdoctoral Fellow at the University of Wisconsin, Madison. "The decline was mostly caused by the influx of explorers and settlers and by their subsequent suppression of wildfires, both intentionally and accidentally."

Marlon earned her doctorate at the University of Oregon, where she studied with co-authors Patrick J. Bartlein and Daniel G. Gavin, professors of geography, as well as with former UO professor Cathy Whitlock, professor of earth sciences at Montana State University. Five other co-authors also hold doctoral degrees from the UO but are now affiliated with other institutions.

Wildfires have been debated for years as either a destructive force of nature that should be eradicated or natural disturbance that keep ecosystems healthy. For nearly 100 years, national policy, as administered by the U.S. Forest Service, had been to respond rapidly to suppress all wildfires, but in recent years, local forest managers have been given more latitude to evaluate which fires to suppress, while ensuring public safety.

In their analysis, Marlon and colleagues used existing records on charcoal deposits in lakebed sediments to establish a baseline of fire activity for the past 3,000 years. They compared that with independent fire-history data drawn from historical records and fire scars on the landscape.

Their key findings:
Comparing charcoal records and climate data, as expected, showed warm, dry intervals, such as the "Medieval Climate Anomaly" between 1,000 and 700 years ago, which had more burning, and cool, moist intervals, such as the "Little Ice Age" between 500 and 300 years ago, had fewer fires. Short-term peaks in fires were associated with abrupt climate changes -- warming or cooling.

Wildfires during most of the 20th century were almost as infrequent as they were during the Little Ice Age, about 400 years ago. However, only a century ago, fires were as frequent as they were about 800 years ago, during the warm and dry Medieval Climate Anomaly. "In other words, humans caused fires to shift from their 1,000-year maximum to their 1,000-year minimum in less than 100 years," Gavin said.

Climate and humans acted synergistically -- by the end of the 18th century and early 19th century -- to increase fire events that were often sparked by agricultural practices, clearing of forests, logging activity and railroading.

"We can use the relationship between climate and fire," Marlon said, "to answer the question: What would the natural level of fire be like today if we didn't work so hard to suppress or eliminate fires? The answer is that because of climate change and the buildup of fuels across the western U.S., levels of burning would be higher than at any time over the past 3,000 years, including the peak in burning during the Medieval Climate Anomaly."

The long-term perspectives gained through these studies demonstrate how strongly climate and people affect the present-day landscapes and forests of the American West, and how they may change in the future, Bartlein said.

"Policymakers and others need to re-evaluate how we think of the past century to allow us to adjust and prepare for the future," he said. "Recent catastrophic wildfires in the West are indicators of a fire deficit between actual levels of burning and that which we should expect given current and coming climate conditions. Policies of fire suppression that do not account for this unusual environmental situation are unsustainable."

The five other co-authors previously at the UO are: Colin J. Long, now at the University of Wisconsin, Oshkosh; Christy E. Briles, now at Monash University in Australia; Daniele Colombaroli, now at the University of Bern in Switzerland; Mitchell J. Power, now at the University of Utah; and Megan K. Walsh, now at Central Washington University in Ellensburg, Wash. The remaining four co-authors are R. Scott Anderson of Northern Arizona University, Kendrick J. Brown of the Canadian Forest Service, Douglas J. Hallett of the University of Calgary and Elizabeth A. Scharf of the University of North Dakota.

"This collaboration of researchers with UO roots provides potentially important information that may be useful in guiding policies to protect the environment," said Kimberly Andrews Espy, vice president for research and innovation. "It is gratifying to see that the impact of graduate study at the UO extends well beyond students' time on our campus. Working together is a hallmark of UO graduate study and reflects well on our nationally ranked geography department."

Charcoal records used in the research were obtained from the Global Charcoal Database of the Global Palaeofire Working Group. Marlon, Bartlein and Power serve on the organization's scientific steering group.

About the University of Oregon

The University of Oregon is among the 108 institutions chosen from 4,633 U.S. universities for top-tier designation of "Very High Research Activity" in the 2010 Carnegie Classification of Institutions of Higher Education. The UO also is one of two Pacific Northwest members of the Association of American Universities.

SOURCES:

Jennifer R. Marlon, postdoctoral researcher, geography, University of Wisconsin, Madison, 203-623-7108, marlon@wisc.edu

Patrick J. Bartlein, professor of geography, UO, 541-346-4967, bartlein@uoregon.edu

Daniel G. Gavin, associate professor of geography, UO, 541-346-5787, dgavin@uoregon.edu

LINKS:

Marlon faculty page (Wisconsin): http://www.pyrogeography.org/

Bartlein faculty page: http://geography.uoregon.edu/bartlein/

Gavin faculty page: http://geography.uoregon.edu/gavin/

UO Science on Facebook: http://www.facebook.com/UniversityOfOregonScience

Jim Barlow | EurekAlert!
Further information:
http://www.uoregon.edu

More articles from Ecology, The Environment and Conservation:

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht World Water Day 2017: It doesn’t Always Have to Be Drinking Water – Using Wastewater as a Resource
17.03.2017 | ISOE - Institut für sozial-ökologische Forschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>