Research Database
Displaying 161 - 180 of 1613
Spatiotemporal dynamics of fine dead surface fuel moisture content in a Colorado mixed-conifer forest
Year: 2025
BackgroundDead fine fuel moisture content (FMC) is critical for predicting fire behavior and effects. Spatiotemporal variation in FMC occurs due to to variability in atmospheric conditions at the fuel interface, which is influenced by interacting factors including local forest structure and topography. Previous research has primarily examined these patterns over coarse spatial scales and relied on few factors to explain variability.AimsIn this study, we monitored the spatiotemporal variability in FMC and characterized how controls of FMC vary over a fire…
Publication Type: Journal Article
Active-fire landscapes demonstrate structural resistance to subsequent fire and drought
Year: 2025
A key tenet of contemporary management in dry, fire-adapted forests of western North America is the reintroduction of a frequent and low- to moderate-severity fire regime. Where this fire regime has been fully or partially restored, it is critical to evaluate the degree to which these landscapes demonstrate forest structural resistance (i.e., the capacity to retain intrinsic structures through time) under novel climates and disturbances. In this study, we used overlapping airborne lidar datasets spanning active-fire landscapes in the Sierra Nevada, California, to evaluate how tree densities,…
Publication Type: Journal Article
Decreasing landscape carbon storage in western US forests with 2 °C of warming
Year: 2025
Changing climate is altering the amount of carbon that can be sustained in forest ecosystems. Increasing heat and drought is already causing increased mortality and decreased regeneration in some locations. These changes have implications for landscape carbon storage with ongoing climate change. We used a climate analogs approach to project aboveground forest carbon density under +2 °C warming above pre-industrial climate for western US forests. We calculated analogs for current climate and under +2 °C warming and associated carbon density for each time period. We found that in most…
Publication Type: Journal Article
Multiple Fire Index Examination of Future Climate Change Affecting Wildfire Seasonality and Extremes in the Contiguous United States
Year: 2025
Climate change is impacting wildfires in the contiguous United States; thus, projections of fire danger under climate change have the potential to inform responses to changing wildfire risks. We calculate fire indices for 13 dynamically downscaled regional climate models, then count days exceeding relevant fire danger thresholds, and compare future changes for mid- and late-twenty-first century relative to a historical reference period. We then compare the responses of the fire indices to highlight areas of agreement and disagreement on the sign and magnitude of future change in fire danger…
Publication Type: Journal Article
Carbon costs of different pathways for reducing fire hazard in the Sierra Nevada
Year: 2025
Restoring a low-intensity, frequent-fire regime in fire-prone forests offers a promising natural climate solution. Management interventions that include prescribed fire and/or mechanical treatments have effectively reduced fire hazards in the Western United States, yet concerns remain regarding their impact on forest carbon storage. This study used results from a long-term, replicated field experiment to assess the impacts of a restored disturbance regime on carbon dynamics in a Sierra Nevada, mixed conifer forest. The carbon consequences of the treatments were compared to a dynamic baseline…
Publication Type: Journal Article
Power and planning: a critical discourse analysis of tribal and non-tribal Oregon wildfire protection plans
Year: 2025
BackgroundSince the late 1800s, the US government has largely removed Indigenous fire stewardship practices from the landscape by implementing a top-down fire suppression system that criminalized traditional fire practices and denaturalized the role of fire in forested environments. A century of routine fire suppression produced dense, homogenous forests capable of sustaining high-intensity wildfire that exceeds the suppression capabilities of land management organizations in many regions, spurring federal leaders to modify management approaches. As part of this change,…
Publication Type: Journal Article
When the wilderness burns: an analysis of current fire management and the case for prescribed fire in designated wilderness in the United States
Year: 2025
BackgroundUnited States wilderness areas face increasing challenges from altered fire regimes and climate change, and land managers face ever more complex decisions about fire use. While federal policies permit various fire management strategies in wilderness, including prescribed fire, managers predominantly rely on suppression despite broad support to restore and sustain fire's natural role in these landscapes. Consequently, wilderness fire regimes continue to diverge from historical norms. To better understand wilderness fire management, we used surveys and interviews with…
Publication Type: Journal Article
Advancing the community health vulnerability index for wildland fire smoke exposure
Year: 2024
Wildland fire smoke risks are not uniformly distributed across people and places, and the most vulnerable communities are often disproportionately impacted. This study develops a county level community health vulnerability index (CHVI) for the Contiguous United States (CONUS) using three major vulnerability components: adaptive capacity, sensitivity, and exposure at the national and regional level. We first calculated sensitivity and adaptive capacity sub-indices using nine sensitivity and twenty adaptive capacity variables. These sub-indices were then combined with an exposure sub-index,…
Publication Type: Journal Article
Bridging scales for landscape-level wildfire adaptation: A case study of the Kittitas Fire Adapted Communities Coalition
Year: 2024
Federal-level strategies or guidance for addressing wildfire risk encourage adaptation activities that span progressively larger scales, often focusing on landscape-level action that necessitates coordination between decision-makers and socially diverse communities. Collaborative organizations are increasingly explored as one approach for coordinating local efforts that address wildfire risk and adaptation, offering a platform for scaling and adjusting federal and state guidance that align with the needs of local landscapes. We conducted semi-structured interviews with members and supporters…
Publication Type: Journal Article
Factors influencing wildfire management decisions after the 2009 US federal policy update
Year: 2024
Background
The decision making process undertaken during wildfire responses is complex and prone to uncertainty. In the US, decisions federal land managers make are influenced by numerous and often competing factors.
Aims
To assess and validate the presence of decision factors relevant to the wildfire decision making context that were previously known and to identify those that have emerged since the US federal wildfire policy was updated in 2009.
Methods
Interviews were conducted across the US while wildfires were actively burning to elucidate time-of-fire decision factors. Data…
Publication Type: Journal Article
Resource objective wildfire leveraged to restore old growth forest structure while stabilizing carbon stocks in the southwestern United States
Year: 2024
Wildfire futures and aboveground carbon (C) dynamics associated with forest restoration programs that integrate resource objective wildfire as part of a larger treatment strategy are not well understood. Using simulation modeling, we examined alternative forest and fuel management strategies on a 237,218-ha study area within a 778,000-ha landscape that is a high priority target for federal restoration programs. We simulated two wildfire management scenarios combined with three levels of conventional forest restoration treatments over 64 years using a detailed landscape disturbance and…
Publication Type: Journal Article
Thinning and prescribed burning increase shade-tolerant conifer regeneration in a fire excluded mixed-conifer forest
Year: 2024
Fire exclusion and past management have altered the composition, structure, and function of frequent-fire forests throughout western North America. In mixed-conifer forests of the California Sierra Nevada, fire exclusion has exacerbated the effects of drought and endemic bark beetles, resulting in extensive mortality of fire-adapted pine species. Thinning and prescribed fire are widely used in these forests to reduce fuels, moderate fire behavior, and restore ecosystems. Tree regeneration influences future forest composition and structure, and therefore future resilience to disturbances, but…
Publication Type: Journal Article
How are long-term stand structure, fuel profiles, and potential fire behavior affected by fuel treatment type and intensity in Interior Pacific Northwest forests?
Year: 2024
Fuel treatments are commonly applied to increase resilience to wildfire in dry and historically frequent-fire forests of western North America. The long-term effects of fuel treatments on forest structure, fuel profiles (amount and configuration of fuels), and potential wildfire behavior are not well known relative to short-term effects. Additionally, long-term treatment effects on the development of stand structure and fuel profiles have rarely been compared to the long-term effects of pre-treatment conditions, treatment intensity, and site productivity. In this study, we addressed these…
Publication Type: Journal Article
Landsat assessment of variable spectral recovery linked to post-fire forest structure in dry sub-boreal forests
Year: 2024
Forest disturbances such as wildfires can dramatically alter forest structure and composition, increasing the likelihood of ecosystem changes. Up-to-date and accurate measures of post-disturbance forest recovery in managed forests are critical, particularly for silvicultural planning. Measuring the live and dead vegetation post-fire is challenging because areas impacted by wildfire may be remote, difficult to access, and/or dangerous to survey. The difficulties of post-fire monitoring are compounded by the global increase in the frequency and severity of disturbances, as expansion of…
Publication Type: Journal Article
Model analysis of post-fire management and potential reburn fire behavior
Year: 2024
Recent trends in wildfire area burned have been characterized by large patches with high densities of standing dead trees, well outside of historical range of variability in many areas and presenting forest managers with difficult decisions regarding post-fire management. Post-fire tree harvesting, commonly called salvage logging, is a controversial management tactic that is often undertaken to recoup economic loss and, more recently, also to reduce future fuel hazard, especially when coupled with surface fuel reduction. It is unclear, however, whether the reductions in future fuels translate…
Publication Type: Journal Article
Increasing prevalence of hot drought across western North America since the 16th century
Year: 2024
Across western North America (WNA), 20th-21st century anthropogenic warming has increased the prevalence and severity of concurrent drought and heat events, also termed hot droughts. However, the lack of independent spatial reconstructions of both soil moisture and temperature limits the potential to identify these events in the past and to place them in a long-term context. We develop the Western North American Temperature Atlas (WNATA), a data-independent 0.5° gridded reconstruction of summer maximum temperatures back to the 16th century. Our evaluation of the WNATA with existing…
Publication Type: Journal Article
Long-term efficacy of fuel reduction and restoration treatments in Northern Rockies dry forests
Year: 2024
Fuel and restoration treatments seeking to mitigate the likelihood of uncharacteristic high-severity wildfires in forests with historically frequent, low-severity fire regimes are increasingly common, but long-term treatment effects on fuels, aboveground carbon, plant community structure, ecosystem resilience, and other ecosystem attributes are understudied. We present 20-year responses to thinning and prescribed burning treatments commonly used in dry, low-elevation forests of the western United States from a long-term study site in the Northern Rockies that is part of the National Fire and…
Publication Type: Journal Article
Guiding principles for transdisciplinary and transformative fire research
Year: 2024
Managing landscape fire is a complex challenge because it is simultaneously necessary for, and increasingly poses a risk to, societies and ecosystems worldwide. This challenge underscores the need for transformative change in the way societies live with and manage fire. While researchers have the potential to act as agents of transformative change, in practice, the ability to affect change is often constrained by siloed and biased expertise, rigid decision-making institutions, and increasingly vulnerable social-ecological systems where urgent rather than long-term solutions are prioritized.…
Publication Type: Journal Article
Exploring spatial heterogeneity in synergistic effects of compound climate hazards: Extreme heat and wildfire smoke on cardiorespiratory hospitalizations in California
Year: 2024
Extreme heat and wildfire smoke events are increasingly co-occurring in the context of climate change, especially in California. Extreme heat and wildfire smoke may have synergistic effects on population health that vary over space. We leveraged high-resolution satellite and monitoring data to quantify spatially varying compound exposures to extreme heat and wildfire smoke in California (2006–2019) at ZIP Code Tabulation Area (ZCTA) level. We found synergistic effects between extreme heat and wildfire smoke on daily cardiorespiratory hospitalizations at the state level. We also found spatial…
Publication Type: Journal Article
Retention of highly qualified wildland firefighters in the Western United States
Year: 2024
Federal agencies responsible for wildland fire management face increasing needs for personnel as fire seasons lengthen and fire size continues to grow, yet federal agencies have struggled to recruit and retain firefighting personnel. While many have speculated that long seasons, challenging working conditions, and low wages contribute to recruitment and retention challenges, there has been…
Publication Type: Journal Article