The influence of ignition technique on fire behaviour in spinifex open woodland in semiarid northern Australia

2015 ◽  
Vol 24 (5) ◽  
pp. 607 ◽  
Author(s):  
Paul R. Williams ◽  
Eleanor M. Collins ◽  
Mick Blackman ◽  
Clare Blackman ◽  
Jackie McLeod ◽  
...  
Keyword(s):  
Fire Severity ◽  
Weather Conditions ◽  
Fire Season ◽  
Northern Australia ◽  
Fire Behaviour ◽  
Factors Influencing ◽  
Crown Scorch ◽  
The World ◽  
Open Woodland ◽  
Season Of Burning

Unplanned, unmanaged wildfires are a significant threat to people, infrastructure and ecosystems around the world. Managed, planned burning is widely used for reducing the incidence, extent or intensity of wildfires. Fire weather and the season of burning are recognised as crucial factors influencing fire behaviour but the demonstrated influence of ignition technique on fire behaviour is not as prominently discussed in relation to planned fires. We found wildfires, irrespective of season, burnt the ground layer more completely (i.e. were less patchy) and produced greater crown scorch severity than did planned fires in a spinifex (Triodia spp.)-dominated open woodland. Fires ignited with a 50-m line burning with the wind produced significantly higher intensities than did line ignition against the wind, and spot ignitions with or against the wind. These data suggest that the higher severity of wildfires in spinifex-dominated habitats is strongly influenced by long fire fronts, in addition to fire season and weather conditions. This study supports the value of planned burning for reducing fire severity and highlights the value of spot ignitions in ecological burning to create a patchily burnt landscape, with limited canopy severity.

scholarly journals What Do the Australian Black Summer Fires Signify for the Global Fire Crisis?

Fire ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 97
Author(s):  
Rachael H. Nolan ◽  
David M. J. S. Bowman ◽  
Hamish Clarke ◽  
Katharine Haynes ◽  
Mark K. J. Ooi ◽  
...  
Keyword(s):  
Climate Change ◽  
Fire Severity ◽  
Social Systems ◽  
Fire Risk ◽  
Weather Conditions ◽  
Lateral Approach ◽  
Rate Of Change ◽  
Fire Season ◽  
Prescribed Burns ◽  
Socially Disadvantaged

The 2019–20 Australian fire season was heralded as emblematic of the catastrophic harm wrought by climate change. Similarly extreme wildfire seasons have occurred across the globe in recent years. Here, we apply a pyrogeographic lens to the recent Australian fires to examine the range of causes, impacts and responses. We find that the extensive area burnt was due to extreme climatic circumstances. However, antecedent hazard reduction burns (prescribed burns with the aim of reducing fuel loads) were effective in reducing fire severity and house loss, but their effectiveness declined under extreme weather conditions. Impacts were disproportionately borne by socially disadvantaged regional communities. Urban populations were also impacted through prolonged smoke exposure. The fires produced large carbon emissions, burnt fire-sensitive ecosystems and exposed large areas to the risk of biodiversity decline by being too frequently burnt in the future. We argue that the rate of change in fire risk delivered by climate change is outstripping the capacity of our ecological and social systems to adapt. A multi-lateral approach is required to mitigate future fire risk, with an emphasis on reducing the vulnerability of people through a reinvigoration of community-level capacity for targeted actions to complement mainstream fire management capacity.

scholarly journals Vegetation and topographical correlates of fire severity from two fires in the Klamath-Siskiyou region of Oregon and California

2006 ◽  
Vol 15 (2) ◽  
pp. 237 ◽  
Author(s):  
John D. Alexander ◽  
Nathaniel E. Seavy ◽  
C. John Ralph ◽  
Bill Hogoboom
Keyword(s):  
Soil Structure ◽  
Fire Severity ◽  
Weather Conditions ◽  
Northern California ◽  
Moderate Severity ◽  
High Severity ◽  
Crown Scorch ◽  
Large Trees ◽  
Topographic Characteristics

We used vegetation data collected in areas before they were burned by the 2500 ha Quartz fire in southern Oregon and the 50 600 ha Big Bar complex in northern California to evaluate the ability of vegetation and topographic characteristics to predict patterns of fire severity. Fire severity was characterized as high, moderate, or low based on crown scorch and consumption, and changes in soil structure. In both fires, vegetation plots with southern aspects were more likely to burn with high severity than plots with eastern, northern, or western aspects. This was the only consistent predictor across both fires. In the Quartz fire, we found that plots at higher elevations and with larger diameter trees were more likely to burn with low or moderate severity. These correlations may have been influenced in part by the effects of unmeasured weather conditions. We found few strong correlates in the Big Bar complex, owing in part to the fact that most (75%) of our plots were in the low-severity category, providing relatively little variation. These results, in combination with previous studies of fire severity in the Klamath-Siskiyou region, suggest that areas with southern aspects tend to burn with greater severity than those of other aspects, areas with large trees burn less severely than those with smaller trees, and that correlates of fire severity vary extensively among fires.

Seasonal differences in fire activity and intensity in tropical savannas of northern Australia using satellite measurements of fire radiative power

2015 ◽  
Vol 24 (2) ◽  
pp. 249 ◽  
Author(s):  
Sofia L. J. Oliveira ◽  
Stefan W. Maier ◽  
José M. C. Pereira ◽  
Jeremy Russell-Smith
Keyword(s):  
Temporal Dynamics ◽  
Fire Severity ◽  
Dry Season ◽  
Fire Season ◽  
Fire Intensity ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Fire Activity ◽  
Radiative Power ◽  
Fire Radiative Power

Earth observation sensors play an important role in quantifying the energy released by fires and capturing their spatial and temporal dynamics. Using estimates of MODIS-derived fire radiative power (FRP) we characterised bushfire activity and intensity in tropical savannas of northern Australia, by season and vegetation type, over the period 2004–2012. Our results indicate that fire activity was highest in the Northern Territory and lowest in Queensland. Mean daily number of fire detections was almost twice as high in the late dry season (August–November) compared to the early dry season (May–July). Fire season was bimodal with fire activity peaks in May and October. Median fire intensity was lower for early dry season fires (29 MW) than late dry season fires (56 MW), and was positively correlated with the number of fire detections. Vegetation types with sparse canopy structure showed lower fire activity and higher intensity. Remote sensing of FRP provides frequent estimates of fire intensity over broad areas, allowing the comparison of this key fire behaviour metric across ecosystems and throughout the fire season. FRP estimates may also be used to draw inferences regarding fire effects, once the complexity and ecosystem-specificity of the relationships between fire intensity and fire severity is acknowledged.

scholarly journals AnANN Model Trained on Regional Data in the Prediction of Particular Weather Conditions

2021 ◽  
Vol 11 (11) ◽  
pp. 4757
Author(s):  
Aleksandra Bączkiewicz ◽  
Jarosław Wątróbski ◽  
Wojciech Sałabun ◽  
Joanna Kołodziejczyk
Keyword(s):  
Atmospheric Pressure ◽  
Real Life ◽  
Real Data ◽  
Weather Conditions ◽  
Maximum Temperature ◽  
Air Masses ◽  
Weather Forecasts ◽  
Life Problems ◽  
The World ◽  
The City

Artificial Neural Networks (ANNs) have proven to be a powerful tool for solving a wide variety of real-life problems. The possibility of using them for forecasting phenomena occurring in nature, especially weather indicators, has been widely discussed. However, the various areas of the world differ in terms of their difficulty and ability in preparing accurate weather forecasts. Poland lies in a zone with a moderate transition climate, which is characterized by seasonality and the inflow of many types of air masses from different directions, which, combined with the compound terrain, causes climate variability and makes it difficult to accurately predict the weather. For this reason, it is necessary to adapt the model to the prediction of weather conditions and verify its effectiveness on real data. The principal aim of this study is to present the use of a regressive model based on a unidirectional multilayer neural network, also called a Multilayer Perceptron (MLP), to predict selected weather indicators for the city of Szczecin in Poland. The forecast of the model we implemented was effective in determining the daily parameters at 96% compliance with the actual measurements for the prediction of the minimum and maximum temperature for the next day and 83.27% for the prediction of atmospheric pressure.

scholarly journals Factors Influencing Students’ Behavior and Attitude Towards Online Education during COVID-19

2021 ◽  
Vol 13 (13) ◽  
pp. 7469
Author(s):  
Gratiela Dana Boca
Keyword(s):  
Online Education ◽  
Online Courses ◽  
Individual Characteristics ◽  
Online Assessment ◽  
Teaching Skills ◽  
Educational Activities ◽  
Online Platforms ◽  
Factors Influencing ◽  
The World

Universities around the world have faced a new pandemic, forcing the closure of campuses that are now conducting educational activities on online platforms. The paper presents a survey about students behavior and attitudes towards online education in the pandemic period from the Technical University of Cluj Napoca, Romania. A group of 300 students participated. The questionnaire was structured in four parts to determine student’s individual characteristics, student’s needs, students’ knowledge in using virtual platforms and students’ quality preferences for online education. The students said that online education in a pandemic situation is beneficial for 78% of them. A total of 41.7% percent of students appreciated the teachers’ teaching skills and the quality of online courses since the beginning of the pandemic, and 18.7% percent of the students appreciated the additional online materials for study to support their education. However, students found online education stressful, but preferred online assessment for evaluation. This pandemic has led to the new stage of Education 4.0, online education, and the need to harmonize methods of education with the requirements of new generations.

scholarly journals Predicting wildfire impacts on the prehistoric archaeological record of the Jemez Mountains, New Mexico, USA

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Megan M. Friggens ◽  
Rachel A. Loehman ◽  
Connie I. Constan ◽  
Rebekah R. Kneifel
Keyword(s):  
New Mexico ◽  
Fire Severity ◽  
Fire Effects ◽  
Burn Severity ◽  
Fire Season ◽  
Archaeological Sites ◽  
Archaeological Record ◽  
Human Environment ◽  
Jemez Mountains ◽  
Archaeological Materials

Abstract Background Wildfires of uncharacteristic severity, a consequence of climate changes and accumulated fuels, can cause amplified or novel impacts to archaeological resources. The archaeological record includes physical features associated with human activity; these exist within ecological landscapes and provide a unique long-term perspective on human–environment interactions. The potential for fire-caused damage to archaeological materials is of major concern because these resources are irreplaceable and non-renewable, have social or religious significance for living peoples, and are protected by an extensive body of legislation. Although previous studies have modeled ecological burn severity as a function of environmental setting and climate, the fidelity of these variables as predictors of archaeological fire effects has not been evaluated. This study, focused on prehistoric archaeological sites in a fire-prone and archaeologically rich landscape in the Jemez Mountains of New Mexico, USA, identified the environmental and climate variables that best predict observed fire severity and fire effects to archaeological features and artifacts. Results Machine learning models (Random Forest) indicate that topography and variables related to pre-fire weather and fuel condition are important predictors of fire effects and severity at archaeological sites. Fire effects were more likely to be present when fire-season weather was warmer and drier than average and within sites located in sloped, treed settings. Topographic predictors were highly important for distinguishing unburned, moderate, and high site burn severity as classified in post-fire archaeological assessments. High-severity impacts were more likely at archaeological sites with southern orientation or on warmer, steeper, slopes with less accumulated surface moisture, likely associated with lower fuel moistures and high potential for spreading fire. Conclusions Models for predicting where and when fires may negatively affect the archaeological record can be used to prioritize fuel treatments, inform fire management plans, and guide post-fire rehabilitation efforts, thus aiding in cultural resource preservation.

Post-fire survival and flushing in three Sierra Nevada conifers with high initial crown scorch

2009 ◽  
Vol 18 (7) ◽  
pp. 857 ◽  
Author(s):  
Chad T. Hanson ◽  
Malcolm P. North
Keyword(s):  
Sierra Nevada ◽  
Pinus Ponderosa ◽  
Fire Severity ◽  
Conifer Species ◽  
Mature Trees ◽  
Salvage Logging ◽  
Abies Magnifica ◽  
Crown Scorch ◽  
Tree Survival ◽  
Large Trees

With growing debate over the impacts of post-fire salvage logging in conifer forests of the western USA, managers need accurate assessments of tree survival when significant proportions of the crown have been scorched. The accuracy of fire severity measurements will be affected if trees that initially appear to be fire-killed prove to be viable after longer observation. Our goal was to quantify the extent to which three common Sierra Nevada conifer species may ‘flush’ (produce new foliage in the year following a fire from scorched portions of the crown) and survive after fire, and to identify tree or burn characteristics associated with survival. We found that, among ponderosa pines (Pinus ponderosa Dougl. ex. Laws) and Jeffrey pines (Pinus jeffreyi Grev. & Balf) with 100% initial crown scorch (no green foliage following the fire), the majority of mature trees flushed, and survived. Red fir (Abies magnifica A. Murr.) with high crown scorch (mean = 90%) also flushed, and most large trees survived. Our results indicate that, if flushing is not taken into account, fire severity assessments will tend to overestimate mortality and post-fire salvage could remove many large trees that appear dead but are not.

Fire regimes and vegetation sensitivity analysis: an example from Bradshaw Station, monsoonal northern Australia

2003 ◽  
Vol 12 (4) ◽  
pp. 349 ◽  
Author(s):  
Cameron Yates ◽  
Jeremy Russell-Smith
Keyword(s):  
Fire History ◽  
Fire Regime ◽  
Landscape Scale ◽  
Fire Season ◽  
Individual Species ◽  
Northern Australia ◽  
Sensitive Species ◽  
Obligate Seeder ◽  
Return Interval ◽  
Noaa Avhrr

The fire-prone savannas of northern Australia comprise a matrix of mostly fire-resilient vegetation types, with embedded fire-sensitive species and communities particularly in rugged sandstone habitats. This paper addresses the assessment of fire-sensitivity at the landscape scale, drawing on detailed fire history and vegetation data assembled for one large property of 9100�km2, Bradshaw Station in the Top End of the Northern Territory, Australia. We describe (1) the contemporary fire regime for Bradshaw Station for a 10 year period; (2) the distribution and status of 'fire sensitive' vegetation; and (3) an assessment of fire-sensitivity at the landscape scale. Fire-sensitive species (FSS) were defined as obligate seeder species with minimum maturation periods of at least 3 years. The recent fire history for Bradshaw Station was derived from the interpretation of fine resolution Landsat MSS and Landsat TM imagery, supplemented with mapping from coarse resolution NOAA-AVHRR imagery where cloud had obstructed the use of Landsat images late in the fire season (typically October–November). Validation assessments of fire mapping accuracy were conducted in 1998 and 1999. On average 40% of Bradshaw burnt annually with about half of this, 22%, occurring after August (Late Dry Season LDS), and 65% of the property burnt 4 or more times, over the 10 year period; 89% of Bradshaw Station had a minimum fire return interval of less than 3 years in the study period. The derived fire seasonality, frequency and return interval data were assessed with respect to landscape units (landsystems). The largest landsystem, Pinkerton (51%, mostly sandstone) was burnt 41% on average, with about 70% burnt four times or more, over the 10 year period. Assessment of the fire-sensitivity of individual species was undertaken with reference to data assembled for 345 vegetation plots, herbarium records, and an aerial survey of the distribution of the long-lived obligate-seeder tree species Callitris intratropica. A unique list of 1310 plant species was attributed with regenerative characteristics (i.e. habit, perenniality, resprouting capability, time to seed maturation). The great majority of FSS species were restricted to rugged sandstone landforms. The approach has wider application for assessing landscape fire-sensitivity and associated landscape health in savanna landscapes in northern Australia, and elsewhere.

Spatial and temporal variations of fire regimes in the Canadian Rocky Mountains and Foothills of southern Alberta

2016 ◽  
Vol 25 (11) ◽  
pp. 1117 ◽  
Author(s):  
Marie-Pierre Rogeau ◽  
Mike D. Flannigan ◽  
Brad C. Hawkes ◽  
Marc-André Parisien ◽  
Rick Arthur
Keyword(s):  
Rocky Mountains ◽  
Fire History ◽  
Fire Severity ◽  
Ecological Integrity ◽  
Fire Regimes ◽  
Temporal Variations ◽  
Fire Season ◽  
Canadian Rocky Mountains ◽  
Southern Alberta ◽  
Fire Exclusion

Like many fire-adapted ecosystems, decades of fire exclusion policy in the Rocky Mountains and Foothills natural regions of southern Alberta, Canada are raising concern over the loss of ecological integrity. Departure from historical conditions is evaluated using median fire return intervals (MdFRI) based on fire history data from the Subalpine (SUB), Montane (MT) and Upper Foothills (UF) natural subregions. Fire severity, seasonality and cause are also documented. Pre-1948 MdFRI ranged between 65 and 85 years in SUB, between 26 and 35 years in MT and was 39 years in UF. The fire exclusion era resulted in a critical departure of 197–223% in MT (MdFRI = 84–104 years). The departure in UF was 170% (MdFRI = 104 years), while regions of continuous fuels in SUB were departed by 129% (MdFRI = 149 years). The most rugged region of SUB is within its historical range of variation with a departure of 42% (MdFRI = 121 years). More mixed-severity burning took place in MT and UF. SUB and MT are in a lightning shadow pointing to a predominance of anthropogenic burning. A summer fire season prevails in SUB, but occurs from spring to fall elsewhere. These findings will assist in developing fire and forest management policies and adaptive strategies in the future.

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