A model of gas mixing into single-entrance tree cavities during wildland fires

2011 ◽  
Vol 41 (8) ◽  
pp. 1659-1670 ◽  
Author(s):  
A.S. Bova ◽  
G. Bohrer ◽  
M.B. Dickinson
Keyword(s):  
Wildland Fire ◽  
Combustion Products ◽  
Great Accuracy ◽  
Picoides Borealis ◽  
Wildland Fires ◽  
Fire Dynamics ◽  
Combustion Gases ◽  
Wind Speeds ◽  
Tree Cavities ◽  
Red Cockaded Woodpecker

The level of protection to fauna provided by tree cavities during wildland fires is not well understood. Here we present a model for estimating the transport of combustion gases into cylindrical, single-entrance cavities during exposures caused by different wildland fire scenarios. In these shelters, the entrance occurs near the top of the cavity. This empirical model was developed from a suite of numerical experiments using the National Institute of Standards and Technology’s Fire Dynamics Simulator, which spanned a range of entrance diameters, wind speeds, gas temperatures, and vertical angles of incidence. To evaluate the model’s predictions, it was used to replicate, with great accuracy, a time series of carbon monoxide (CO) concentrations in a controlled experiment where a fabricated cylindrical cavity was exposed to combustion products. The time constant for cavity filling is proportional to the ratio of cavity volume to entrance area. Hot gases lead to significant stratification within the cavity during exposures. To demonstrate the model’s potential use in predicting faunal exposures in the context of land management, we show that the model can be used to estimate dosage within red-cockaded woodpecker (Picoides borealis Vieillot, 1809) cavities without requiring temporally detailed, local measurements of wind speed and combustion product concentrations.

scholarly journals Current Wildland Fire Patterns and Challenges in Europe: A Synthesis of National Perspectives

2021 ◽  
Vol 14 ◽  
pp. 117862212110281
Author(s):  
Nieves Fernandez-Anez ◽  
Andrey Krasovskiy ◽  
Mortimer Müller ◽  
Harald Vacik ◽  
Jan Baetens ◽  
...  
Keyword(s):  
Land Use ◽  
Large Scale ◽  
Wildland Fire ◽  
Human Life ◽  
Local Analysis ◽  
Wildland Fires ◽  
Fire Statistics ◽  
Quantitative Evidence ◽  
Wide Range ◽  
Fire Patterns

Changes in climate, land use, and land management impact the occurrence and severity of wildland fires in many parts of the world. This is particularly evident in Europe, where ongoing changes in land use have strongly modified fire patterns over the last decades. Although satellite data by the European Forest Fire Information System provide large-scale wildland fire statistics across European countries, there is still a crucial need to collect and summarize in-depth local analysis and understanding of the wildland fire condition and associated challenges across Europe. This article aims to provide a general overview of the current wildland fire patterns and challenges as perceived by national representatives, supplemented by national fire statistics (2009–2018) across Europe. For each of the 31 countries included, we present a perspective authored by scientists or practitioners from each respective country, representing a wide range of disciplines and cultural backgrounds. The authors were selected from members of the COST Action “Fire and the Earth System: Science & Society” funded by the European Commission with the aim to share knowledge and improve communication about wildland fire. Where relevant, a brief overview of key studies, particular wildland fire challenges a country is facing, and an overview of notable recent fire events are also presented. Key perceived challenges included (1) the lack of consistent and detailed records for wildland fire events, within and across countries, (2) an increase in wildland fires that pose a risk to properties and human life due to high population densities and sprawl into forested regions, and (3) the view that, irrespective of changes in management, climate change is likely to increase the frequency and impact of wildland fires in the coming decades. Addressing challenge (1) will not only be valuable in advancing national and pan-European wildland fire management strategies, but also in evaluating perceptions (2) and (3) against more robust quantitative evidence.

scholarly journals Unmanned Aerial Vehicles for Wildland Fires: Sensing, Perception, Cooperation and Assistance

Drones ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 15
Author(s):  
Moulay A. Akhloufi ◽  
Andy Couturier ◽  
Nicolás A. Castro
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Wildland Fire ◽  
Fire Intensity ◽  
Economic Losses ◽  
Small Scale ◽  
Environmental Damage ◽  
Unmanned Aerial Systems ◽  
Wildland Fires ◽  
Natural Risk ◽  
Aerial Vehicles

Wildfires represent a significant natural risk causing economic losses, human death and environmental damage. In recent years, the world has seen an increase in fire intensity and frequency. Research has been conducted towards the development of dedicated solutions for wildland fire assistance and fighting. Systems were proposed for the remote detection and tracking of fires. These systems have shown improvements in the area of efficient data collection and fire characterization within small-scale environments. However, wildland fires cover large areas making some of the proposed ground-based systems unsuitable for optimal coverage. To tackle this limitation, unmanned aerial vehicles (UAV) and unmanned aerial systems (UAS) were proposed. UAVs have proven to be useful due to their maneuverability, allowing for the implementation of remote sensing, allocation strategies and task planning. They can provide a low-cost alternative for the prevention, detection and real-time support of firefighting. In this paper, previous works related to the use of UAV in wildland fires are reviewed. Onboard sensor instruments, fire perception algorithms and coordination strategies are considered. In addition, some of the recent frameworks proposing the use of both aerial vehicles and unmanned ground vehicles (UGV) for a more efficient wildland firefighting strategy at a larger scale are presented.

Decline of the Red-Cockaded Woodpecker (Picoides borealis) in Southeastern Oklahoma

1994 ◽  
Vol 132 (2) ◽  
pp. 275 ◽  
Author(s):  
Jeffrey F. Kelly ◽  
Sandra M. Pletschet ◽  
David M. Leslie
Keyword(s):  
Picoides Borealis ◽  
Red Cockaded Woodpecker

scholarly journals Local measurements of wildland fire dynamics in a field-scale experiment

2018 ◽  
Vol 194 ◽  
pp. 452-463 ◽  
Author(s):  
Eric V. Mueller ◽  
Nicholas Skowronski ◽  
Jan C. Thomas ◽  
Kenneth Clark ◽  
Michael R. Gallagher ◽  
...  
Keyword(s):  
Wildland Fire ◽  
Field Scale ◽  
Fire Dynamics ◽  
Local Measurements ◽  
Scale Experiment

Striking repercussions of the Australian "Black Summer" bushfires on the stratospheric composition and dynamical circulation

2021 ◽  
Author(s):  
Sergey Khaykin ◽  
Bernard Legras ◽  
Silvia Bucci ◽  
Pasquale Sellitto ◽  
Lars Isaksen ◽  
...  
Keyword(s):  
Volcanic Eruptions ◽  
Combustion Products ◽  
Stratospheric Aerosol ◽  
Radiative Balance ◽  
Combustion Gases ◽  
Gaseous Composition ◽  
Stratospheric Composition ◽  
Radiative Transfer Modeling ◽  
Total Column ◽  
Meteorological Analysis

<p>Wildfire-driven pyro-convection (PyroCb) is capable of lofting combustion products into the stratosphere, polluting it with smoke aerosols at hemispheric and yearly scales. This realization has emerged after the record-breaking British Columbia PyroCb event in August 2017 that approached moderate volcanic eruptions in terms of stratospheric aerosol load perturbation. The Australian “Black Summer” bushfires in 2019/20 have surpassed the previous record by a factor of 3 and rivaled the strongest volcanic eruptions in the XXI century. Here we exploit a synergy of various satellite observations, ECMWF meteorological analysis and radiative transfer modeling to quantify the perturbation of stratospheric particulate and gaseous composition, dynamical circulation and radiative balance caused by the Australian New Year’s PyroCb outbreak. One of the most striking repercussions of this event was the generation of several persistent anticyclonic vortices that provided confinement to the PyroCb plumes and preserved them from rapid dilution in the environment. The most intense vortex measured 1000 km in diameter, persisted in the stratosphere for over 13 weeks and lifted a confined bubble of combustion gases, aerosols and moisture to 35 km altitude. It was accompanied by a synoptic-scale ozone hole with the total column reduction by about 30%. The startling consequences of the Australian event provide new insights into climate-altering potential of the wildfires, that have increased in frequency and strength over the recent years.</p>

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