Western Mountain Initiative: Southern Rocky Mountains
Science Center Objects
Mountain ecosystems of the western U.S. provide irreplaceable goods and services such as water, wood, biodiversity, and recreational opportunities, but their potential responses to projected climatic patterns are poorly understood. The overarching objective of the Western Mountain Initiative (WMI) is to understand and predict the responses—emphasizing sensitivities, thresholds, resistance, and resilience—of western mountain ecosystems to climatic variability and change.
The WMI - Southern Rocky Mountains project, with diverse research partners, works on forests in the Southwest to: 1) elucidate centennial- to millennial-length shifts in past vegetation and fire regimes; 2) study responses of fire to short-term (annual to decadal) climatic variation; 3) determine drivers of tree mortality, including drought-stress thresholds for dieback; 4) assess patterns of post-disturbance ecosystem recovery; and 5) understand the joint effects of climatic variability, fire, and land use on watershed runoff and erosion processes.
Golden aspen, Jemez Mountains, NM. Photo by Craig D. Allen, USGS. Public domain.
Two months after the Las Conchas fire, "moonscape" on Sanchez Mesa, NM, 2011. Photo by Craig D. Allen. Public domain.
-
Date published: September 23, 2016Status: ActiveThe New Mexico Landscapes Field Station
The New Mexico Landscapes Field Station is a place-based, globally-connected, ecological research group that studies and interprets ecosystem and wildlife dynamics, working with land managers and community leaders to deliver solutions that foster the linked health of human and natural systems.
Our partnerships, and co-location, with land management agencies provide us with opportunities...
Contacts: Ernie Valdez, Ph.D., Ellis Q Margolis, Ph.D., Kay Beeley, Manuel Lopez -
Date published: September 22, 2016Status: ActiveThe Western Mountain Initiative (WMI)
Western Mountain Initiative (WMI) is a long-term collaboration between FORT, WERC, NOROCK, USFS, NPS, LANL, and universities worldwide to address changes in montane forests and watersheds due to climate change. Current emphases include altered forest disturbance regimes (fire, die-off, insect outbreaks) and hydrology; interactions between plants, water, snow, nutrient cycles, and climate; and...
Attribution: Fort Collins Science Center -
Date published: August 2, 2016Status: ActiveWestern Mountain Initiative: Central Rocky Mountains
Mountain ecosystems of the western U.S. provide irreplaceable goods and services such as water, wood, biodiversity, and recreational opportunities, but their responses to global changes are poorly understood. The overarching objective of the Western Mountain Initiative (WMI) is to understand and predict the responses, emphasizing sensitivities, thresholds, resistance, and resilience, of...
Contacts: Jill Baron, Ph.D.Attribution: Fort Collins Science Center
Multi-scale predictions of massive conifer mortality due to chronic temperature rise
Global temperature rise and extremes accompanying drought threaten forests and their associated climatic feedbacks. Our ability to accurately simulate drought-induced forest impacts remains highly uncertain in part owing to our failure to integrate physiological measurements, regional-scale models, and dynamic global vegetation...
McDowell, Nathan G.; Williams, A.P.; Xu, C.; Pockman, W. T.; Dickman, L. T.; Sevanto, Sanna; Pangle, R.; Limousin, J.; Plaut, J.J.; Mackay, D.S.; Ogee, J.; Domec, Jean-Christophe; Allen, Craig D.; Fisher, Rosie A.; Jiang, X.; Muss, J.D.; Breshears, D.D.; Rauscher, Sara A.; Koven, C. Larger trees suffer most during drought in forests worldwide
The frequency of severe droughts is increasing in many regions around the world as a result of climate change. Droughts alter the structure and function of forests. Site- and region-specific studies suggest that large trees, which play keystone roles in forests and can be disproportionately important to ecosystem carbon storage and...
Bennett, Amy C.; McDowell, Nathan G.; Allen, Craig D.; Anderson-Teixeira, Kristina J. On underestimation of global vulnerability to tree mortality and forest die-off from hotter drought in the Anthropocene
Patterns, mechanisms, projections, and consequences of tree mortality and associated broad-scale forest die-off due to drought accompanied by warmer temperatures—“hotter drought”, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and...
Allen, Craig D.; Breshears, David D.; McDowell, Nathan G. Patterns and causes of observed piñon pine mortality in the southwestern United States
Recently, widespread piñon pine die-off occurred in the southwestern United States. Here we synthesize observational studies of this event and compare findings to expected relationships with biotic and abiotic factors. Agreement exists on the occurrence of drought, presence of bark beetles and increased mortality of larger trees. However,...
Meddens, Arjan J.H.; Hicke, Jeff H.; Macalady, Alison K.; Buotte, P.C.; Cowles, T.R.; Allen, Craig D. Unsupported inferences of high-severity fire in historical dry forests of the western United States: Response to Williams and Baker
Reconstructions of dry western US forests in the late 19th century in Arizona, Colorado and Oregon based on General Land Office records were used by Williams & Baker (2012; Global Ecology and Biogeography, 21, 1042–1052; hereafter W&B) to infer past fire regimes with substantial moderate and high-severity burning. The authors concluded...
Fulé, Peter Z.; Swetnam, Thomas W.; Brown, Peter M.; Falk, Donald A.; Peterson, David L.; Allen, Craig D.; Aplet, Gregory H.; Battaglia, Mike A.; Binkley, Dan; Farris, Calvin; Keane, Robert E.; Margolis, Ellis Q.; Grissino-Mayer, Henri; Miller, Carol; Sieg, Carolyn Hull; Skinner, Carl; Stephens, Scott L.; Taylor, Alan Post-fire wood management alters water stress, growth, and performance of pine regeneration in a Mediterranean ecosystem
Extensive research has focused on comparing the impacts of post-fire salvage logging versus those of less aggressive management practices on forest regeneration. However, few studies have addressed the effects of different burnt-wood management options on seedling/sapling performance, or the ecophysiological mechanisms underlying differences...
Maranon-Jimenez, Sara; Castro, Jorge; Querejeta, José Ignacio; Fernandez-Ondono, Emilia; Allen, Craig D. An integrated model of environmental effects on growth, carbohydrate balance, and mortality of Pinus ponderosa forests in the southern Rocky Mountains
Climate-induced tree mortality is an increasing concern for forest managers around the world. We used a coupled hydrologic and ecosystem carbon cycling model to assess temperature and precipitation impacts on productivity and survival of ponderosa pine (Pinus ponderosa). Model predictions were evaluated using observations of productivity and...
Tague, Christina L.; McDowell, Nathan G.; Allen, Craig D. Projected future changes in vegetation in western North America in the 21st century
Rapid and broad-scale forest mortality associated with recent droughts, rising temperature, and insect outbreaks has been observed over western North America (NA). Climate models project additional future warming and increasing drought and water stress for this region. To assess future potential changes in vegetation distributions in western NA,...
Xiaoyan, Jiang; Rauscher, Sara A.; Ringler, Todd D.; Lawrence, David M.; Williams, A. Park; Allen, Craig D.; Steiner, Allison L.; Cai, D. Michael; McDowell, Nate G. Key landscape ecology metrics for assessing climate change adaptation options: Rate of change and patchiness of impacts
Under a changing climate, devising strategies to help stakeholders adapt to alterations to ecosystems and their services is of utmost importance. In western North America, diminished snowpack and river flows are causing relatively gradual, homogeneous (system-wide) changes in ecosystems and services. In addition, increased climate variability is...
López-Hoffman, Laura; Breshears, David D.; Allen, Craig D.; Miller, Marc L. Carbon stocks of trees killed by bark beetles and wildfire in the western United States
Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined...
Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A. Watering the forest for the trees: An emerging priority for managing water in forest landscapes
Widespread threats to forests resulting from drought stress are prompting a re-evaluation of priorities for water management on forest lands. In contrast to the widely held view that forest management should emphasize providing water for downstream uses, we argue that maintaining forest health in the context of a changing climate may require...
Grant, Gordon E.; Tague, Christina L.; Allen, Craig D. Quantifying tree mortality in a mixed species woodland using multitemporal high spatial resolution satellite imagery
Widespread tree mortality events have recently been observed in several biomes. To effectively quantify the severity and extent of these events, tools that allow for rapid assessment at the landscape scale are required. Past studies using high spatial resolution satellite imagery have primarily focused on detecting green, red, and gray tree...
Garrity, Steven R.; Allen, Craig D.; Brumby, Steven P.; Gangodagamage, Chandana; McDowell, Nate G.; Cai, D. Michael