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Ellis Q Margolis

Research Ecologist

Fort Collins Science Center

Office Phone: 505-954-2251
ORCID: 0000-0002-0595-9005

Jemez Mountains Field Station1
301 Dinosaur Trail
Santa Fe , NM 87507

Supervisor: Kathryn A Schoenecker
Increasing wildfire activity in much of North America is having severe impacts on society and ecosystems. Climate change is a key driver of changing fire regimes across North America, with varying expressions across the continent. Modern fire records, while useful, are too short to fully characterize the complex patterns and non-linear dynamics of fire-climate relationships that are required to understand future fire activity in a warmer climate. Tree-ring fire scars offer a unique perspective because they are spatially precise, direct evidence of fires with annual to sub-annual resolution spanning centuries. For the first time, we have compiled tree-ring fire scar records across North America (n = 2,593 sites,...
Wildfires are increasing across the western U.S., causing damage to ecosystems and communities. Addressing the fire problem requires understanding the trends and drivers of fire, yet most fire data is limited only to recent decades. Tree-ring fire scars provide fire records spanning 300-500 years, yet these data are largely inaccessible to potential users. Our project will deliver the newly compiled North American Fire Scar Network — 2,592 sites, 35,602 trees, and > 300,000 fire records — to fire scientists, managers and the public through an online application that will provide tools to explore, visualize, and analyze fire history data. The app will provide raw and derived data products, graphics, statistical summaries,...
Fire size and severity continue to increase across large parts of North America, driven by a combination of climate change and effects of human land use. Instrumental records are too short to fully understand patterns, trends, and drivers of fire that are necessary to model future fire. Tree-ring fire scars provide centuries-long records of fire regimes, including fire frequency, season, size, and fire-climate relationships. We compiled fire-scar site descriptions from > 100 researchers across the continent to produce the first North American tree-ring fire-scar network. These data provide descriptive information for all known tree-ring fire-scar sites in North America. Data fields include location, name, area and...
Abstract Background Forest and nonforest ecosystems of the western United States are experiencing major transformations in response to land-use change, climate warming, and their interactive effects with wildland fire. Some ecosystems are transitioning to persistent alternative types, hereafter called “vegetation type conversion” (VTC). VTC is one of the most pressing management issues in the southwestern US, yet current strategies to intervene and address change often use trial-and-error approaches devised after the fact. To better understand how to manage VTC, we gathered managers, scientists, and practitioners from across the southwestern US to collect their experiences with VTC challenges, management responses,...
The data include ages and locations of presence/absence surveys for sagebrush (Artemesia tridentata) on the Bureau of Land Management Rio Grande del Norte National Monument, New Mexico. We sampled cross-sections of sagebrush along 11 General Land Office section survey lines and conducted growth ring analysis to produce inner-ring dates for 93 sagebrush plants. The presence/absence surveys were conducted along the same section lines as the growth ring samples and were compared to the original surveys from 1881 to assess vegetation change on the landscape.
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