Western Mountain Initiative: 

Predicting Ecosystem Responses to Climate Change

Printed on recycled paper U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2008-3093

November 2008

Workshops

Fire History and Climate Synthesis in Western North 

America (2005)

As a result of this meeting of tree ring and charcoal specialists (http://www4.nau.edu/firehistory/index.htm), special 

symposia were held at the Third International Fire Ecology and Management Congress (San Diego, 2006) and the 

International Association for Landscape Ecology (Tucson, 

2007). Proceedings compose a special issue of the International Journal of Wildland Fire (v. 17, no. 1) on “Fire 

Climatology” (see http://www.publish.csiro.au/nid/115/

issue/4151.htm).

State of Knowledge on Alpine Treeline Ecotones and 

Treeline Dynamics (2005)

This workshop of 35 leading treeline scientists is published 

as “Alpine Treeline of Western North America: Linking 

Organism-to-Landscape Dynamics”: Malanson and others, 

Physical Geography (2007), v. 28, p. 378–396 (see http://

bellwether.metapress.com/content/gj25g46703607153/).

Mountain ecosystems of the western United States provide irreplaceable goods and 

services such as water, timber, biodiversity, and recreational opportunities, but their responses 

to climatic changes are complex and not well understood. Moreover, other ecological 

disturbances such as wildfire, insect outbreaks, and the spread of invasive species interact 

synergistically with warmer temperatures and accelerate ecosystem changes. The rate and 

magnitude of ecosystem responses to changes in the global atmospheric environment are 

variable and uncertain, ranging from gradual to abrupt and from moderate to profound. 

The responses of greatest importance to policy makers and land managers are also the least 

understood and least predictable: responses that are both abrupt and profound. 

Scientists from several biology centers of the U.S. Geological Survey (USGS) and U.S. 

Forest Service are studying climate change and ecological interactions to better understand 

and predict likely outcomes in the mountainous American West. The Western Mountain 

Initiative (WMI) collaborates with U.S. Forest Service, National Park Service, and university 

partners that study global change in mountain ecosystems of the western United States. As 

part of the USGS Global Change Science program, the WMI seeks to understand and predict 

the responses—emphasizing sensitivities, thresholds, resistance, and resilience—of western 

mountain ecosystems to climatic variability and change.

WMI catalyzes assessment and synthesis of the effects of disturbance and climate 

change across western mountain areas, focusing on national parks and surrounding national 

forests. WMI scientists nurture close working relationships with each other, the larger science community, and land and resource 

managers with whom they have cooperated for many years. They take an ecosystem approach to science, integrating research 

across science disciplines at scales ranging from field studies to global trends.

Climate Change and Disturbance Interactions in 

Western North America (2007) 

Researchers in climatology, ecosystem science, fire and 

insect ecology, and landscape modeling integrated knowledge involving interactions among disturbance regimes that 

could accelerate ecosystem change. The workshop report is 

published as “Climate Change and Disturbance Interactions”: McKenzie, D., and C.D. Allen, EOS, Transactions 

American Geophysical Union (2007), v. 88, no. 21, 

doi:10.1029/2007EO210010 (http://www.agu.org/pubs/

crossref/2007/2007EO210010.shtml) 

Web Sites and Web-based Applications

CHARSTER software package manages and analyzes sedimentary charcoal data, improves data integration between 

studies, and facilitates geographic studies of paleofire and 

climate records. See http://geography.uoregon.edu/gavin/

charster/Introduction.html.

Glaciers Online: Glaciers of the American West provides 

interactive maps, photos, and data for these glaciers. See 

http://glaciers.research.pdx.edu/index.php.

RHESSys (Regional HydroEcological Simulation System)

addresses the responses of western mountain ecosystems 

to climate change. RHESSys is a GIS-based hydroecological modeling framework that simulates water, carbon, and 

nutrient fluxes. See http://fiesta.bren.ucsb.edu/~rhessys/.

WMI Accomplishments 

In addition to more than 170 published and in-press books, 

reports, and manuscripts, the WMI sponsors workshops, 

Web-based application and database development, and major 

collaborations. The following are recent examples:

Tripod Fire, Washington State. Photograph by 

Philip Higuera, Montana State Univ.

.
National/International Collaboration

•	 The Consortium for Integrated Climate Research in Western Mountains (CIRMOUNT) brings together USGS, U.S. 

Forest Service, National Oceanic and Atmospheric Administration, and university scientists to improve understanding 

and integrate applications about climate in western mountains 

and effects on ecosystems. WMI scientists hold positions on 

the CIRMOUNT advisory board. See http://www.fs.fed.us/

psw/cirmount/.

•	 WMI partners cooperate with CORFOR, the Cordillera Forest Dynamics Network (North and South 

American mountains: see http://mri.scnatweb.ch/networks/

mri-amercian-cordillera/-cordillera-forest-dynamics-networkcorfor.html) and MRI, the Mountain Research Initiative, 

which tracks and addresses global change issues in mountain 

regions around the world. See http://www.mri.scnatweb.ch/.

Leading Research Published on Forest Dynamics 

and Disturbance

Climatic change, wildfire, and conservation: McKenzie and 

others, Conservation Biology (2004), v. 18, p. 890–902 

(http://www.fs.fed.us/r6/fish/conservation-biology/05-fireclimatechange-2004.pdf). 

Regional vegetation die-off in response to global-changetype drought: Breshears and others, Proceedings of the 

National Academy of Sciences (2005), v. 102, p. 15144–

15148 (http://www.pnas.org/content/102/42/15144.abstract).

Changing temperatures influence suitability for modeled 

mountain pine beetle (Dendroctonus ponderosae) outbreaks in the western United States: Hicke and others, 

Journal of Geophysical Research (2006), v. 111, G02019, 

DOI:10.1029/2005JG000101 (http://www.agu.org/pubs/

crossref/2006/2005JG000101.shtml).

Apparent climatically induced increase of tree mortality 

rates in a temperate forest: van Mantgem and others, 

Ecology Letters (2007), v. 10, p. 909–916, DOI:10.1111/

WMI Online Resources

Western Mountain Initiative (USGS Web site)

http://biology.usgs.gov/ecosystems/global_change/wmi.html

Western Mountain Initiative

http://www.cfr.washington.edu/research.fme/wmi/index.htm

USGS Global Change Program

http://www.usgs.gov/global_change/

Current Global Change Projects: Response of Western Mountain Ecosystems to Climatic Variability and 

Change—The Western Mountain Initiative

http://biology.usgs.gov/ecosystems/global_change/western_mountain.html

MRI Newsletter 10: The Western Mountain Initiative 

(WMI)—More Than the Sum of Its Parts

http://mri.scnatweb.ch/dmdocuments/MRI_Newsletter_

no10.pdf

Park Science: Response of Western Mountain Ecosystems to Climatic Variability and Change—The Western 

Mountain Initiative

http://www.werc.usgs.gov/seki/pdfs/WMI_Park%20

Science_2006.pdf

Select WMI Products

Rocky Mountain Futures: An Ecological Perspective.

Leading ecologists, geographers, and other scientists 

provide a comprehensive examination of the ecological 

consequences of past and current human activities in the 

Rocky Mountain region in North America. The authors 

project future effects based on current economic and 

social trends and emergent patterns. (J. Baron, ed., 2002, 

Island Press.)

Sustaining Rocky Mountain Landscapes: Science, 

Policy and Management of the Crown of the Continent 

Ecosystem. The authors offer a systematic, multidisciplinary assessment of the challenges involved in managing the Crown of the Continent Ecosystem, an area that 

includes northwestern Montana, southwestern Alberta, 

and southeastern British Columbia. (T. Prato and D. Fagre, 

eds., 2007, RFF Press) 

Preliminary Review of Adaptation Options for 

Climate-Sensitive Ecosystems and Resources: 

Final Report. (Science and Assessment Product 4.4 of the 

U.S. Climate Change Science Program.) WMI researchers were lead and contributing authors in this 2008 report, 

which identifies current and potential activities on public lands that can be used to prepare for climate-caused 

impacts on natural resources. Available at http://www.

climatescience.gov/Library/sap/sap4-4/final-report/default.

htm#finalreport.

j.1461-0248.2007.01080.x (http://www.werc.usgs.gov/seki/

pdfs/van%20Mantgem%20&%20Stephenson%202007.pdf).

Douglas-fir growth in mountain ecosystems: water limits 

tree growth from stand to region: Littell and others, Ecological Monographs (2008), v. 78, p. 349–368 (http://www.

esajournals.org/doi/abs/10.1890/07-0712.1).

Spatial patterns of transpiration response to climate 

variability in a snow-dominated mountain ecosystem:

Christensen and others, Hydrological Processes (2008), 

DOI:10.1002/hyp.696 (http://www3.interscience.wiley.com/

cgi-bin/fulltext/117883644/PDFSTART). 

Contact Information

Craig Allen (craig_allen@

usgs.gov; USGS Fort 

Collins Science Center, 

Jemez Mountains Field 

Station)

Jill Baron (jill_baron@

usgs.gov; USGS Fort 

Collins Science Center, 

Colorado State University 

Natural Resource Ecology 

Laboratory)

Dan Fagre (dan_fagre@ 

usgs.gov; USGS Northern 

Rocky Mountain Science 

Center)

Don McKenzie (donaldmckenzie@fs.fed.us; U.S. Forest 

Service, Pacific Northwest Research Station)

David Peterson (peterson@fs.fed.us; U.S. Forest Service, 

Pacific Northwest Research Station)

Nate Stephenson (nstephenson@usgs.gov; USGS Western 

Ecological Science Center)

Photograph by Manuel Toro, Univ. of Madrid.