Uncontrolled Fires Research Articles

Wood properties of teak (Tectona grandis) from a mature unmanaged stand in East Timor

The wood quality from 50- to 70-year-old Tectona grandis trees from an unmanaged forest in East Timor was assessed. The aim was to evaluate teak in mature stands that had undergone uncontrolled disturbances, e.g., fire and local community usage. Heartwood represented 91% of the tree radius at a height of 1.7 m, and sapwood contained on average nine rings. The mean ring width showed within-tree and between-tree variability. The chemical compositions of heartwood and sapwood were similar. Within-tree chemical variation occurred only in terms of extractives, which increased from the pith (8.3%) to the heartwood-sapwood transition (12.7%) and decreased in the sapwood (9.2%). Overall, the wood properties of teak from a unmanaged forest in East Timor were comparable to those reported for plantation teaks of other origin: 607 kg/m3 basic density, 3.5% and 5.2% radial and tangential shrinkage, 141 N/mm2 modulus of rupture, 10684 N/mm2 modulus of elasticity, and 50 N/mm2 maximum crushing strength in compression parallel to the grain. Disturbances on individual tree growth arising from the unmanaged status of the stand were evidenced by higher within-tree variability of ring width. However, the longitudinal and radial variations of wood density and mechanical properties were of low magnitude and in a degree that did not negatively impact on timber quality.

Stocks and fluxes of carbon associated with land use change in Southeast Asian tropical peatlands: A review

[1] The increasing and alarming trend of degradation and deforestation of tropical peat swamp forests may contribute greatly to climate change. Estimates of carbon (C) losses associated with land use change in tropical peatlands are needed. To assess these losses we examined C stocks and peat C fluxes in virgin peat swamp forests and tropical peatlands affected by six common types of land use. Phytomass C loss from the conversion of virgin peat swamp forest to logged forest, fire-damaged forest, mixed croplands and shrublands, rice field, oil palm plantation, and Acacia plantation were calculated using the stock difference method and estimated at 116.9 ± 39.8, 151.6 ± 36.0, 204.1 ± 28.6, 214.9 ± 28.4, 188.1 ± 29.8, and 191.7 ± 28.5 Mg C ha−1, respectively. Total C loss from uncontrolled fires ranged from 289.5 ± 68.1 Mg C ha−1 in rice fields to 436.2 ± 77.0 Mg C ha−1 in virgin peat swamp forest. We assessed the effects of land use change on C stocks in the peat by looking at how the change in vegetation cover altered the main C inputs (litterfall and root mortality) and outputs (heterotrophic respiration, CH4 flux, fires, and soluble and physical removal) before and after conversion. The difference between the soil input-output balances in the virgin peat swamp forest and in the oil palm plantation gave an estimate of peat C loss of 10.8 ± 3.5 Mg C ha−1 yr−1. Peat C loss from other land use conversions could not be assessed due to lack of data, principally on soil heterotrophic respiration rates. Over 25 years, the conversion of tropical virgin peat swamp forest into oil palm plantation represents a total C loss from both biomass and peat of 427.2 ± 90.7 Mg C ha−1 or 17.1 ± 3.6 Mg C ha−1 yr−1. In all situations, peat C loss contributed more than 63% to total C loss, demonstrating the urgent need in terms of the atmospheric greenhouse gas burden to protect tropical virgin peat swamp forests from land use change and fires.

Seasonal variability in the optical properties of Baltic aerosols

A five-year dataset of spectral aerosol optical thickness was used to analyse the seasonal variability of aerosol optical properties (the aerosol optical thickness (AOT) at wavelength λ = 500nm, AOT(500) and the Ångström exponent for the 440–870nm spectral range, α(440, 870)) over the Baltic Sea and dependence of these optical properties on meteorological factors (wind direction, wind speed and relative humidity). The data from the Gotland station of the global radiometric network AERONET (Aerosol Robotic Network, http://aeronet.gsfc.nasa.gov) were taken to be representative of the Baltic Sea conditions. Meteorological observations from Fårosund were also analysed.Analysis of the data from 1999 to 2003 revealed a strong seasonal cycle in AOT(500) and α(440, 870). Two maxima of monthly mean values of AOT(500) over the Baltic were observed. In April, an increase in the monthly mean aerosol optical thickness over Gotland most probably resulted from agricultural waste straw burning, mainly in northern Europe and Russia as well as in the Baltic states, Ukraine and Belarus. During July and August, the aerosol optical thickness was affected by uncontrolled fires (biomass burning). There was a local minimum of AOT(500) in June.Wind direction, a local meteorological parameter strongly related to air mass advection, is the main meteorological factor influencing the variability of aerosol optical properties in each season. The highest mean values of AOT(500) and α(440, 870) occurred with easterly winds in both spring and summer, but with southerly winds in autumn.

The quantitative investigation on people's pre-evacuation behavior under fire

With the growth in urbanization process and activities in Hong Kong and many large cities in China, a great number of super high-rise buildings have been constructed in these years. The occurrences of many large fire tragedies, especially the US 9/11 terrorist attack, made people aware that super high-rise buildings may cause serious fatalities, and extremely they could collapse in a huge uncontrolled fire. Compared with people's evacuation behavior, little interests have been drawn to pre-movement behavior. In Hong Kong and some major cities in China, over 90% of people are living in multi-storey multi-compartment buildings. Their awareness and responses to fire incidents happening in the other parts of the same building have substantial influence on the whole evacuation process. Studies on pre-evacuation human behavior have been performed for many years, but the vast majority of the studies were qualitative-oriented. Accordingly, an attempt was made in this article to quantitatively investigate people's pre-evacuation behavior by using the Support Vector Machine (SVM) approach, which was trained by Hong Kong's post-fire field survey data.

Christchurch Architecture and the Earthquakes of 4 September 2010 and 22 February 2011

Throughout history patterns of urban development have been punctuated by cataclysmic events. Volcanic eruptions, earthquakes, uncontrolled fires and warfare have laid waste to cities from Pompeii to Lisbon, London to Chicago and Dresden to Hiroshima. To this list the New Zealand city of Christchurch must now be added. Founded in 1850 as the provincial capital of Canterbury, the last and most idealistic of the New Zealand Company's settlements, Christchurch is located on the eastern edge of the alluvial plain that extends from the Southern Alps to Banks Peninsula. Situated on marshy ground between the Avon and Heathcote Rivers and close to the volcanic hills that separate the city and plain from the port of Lyttelton, in 1850 this must have seemed a strategic and well chosen site, with an ample harbour, abundant water and an expansive hinterland suitable for agricultural exploitation. And so it seemed for the next century and a half. The city developed rapidly, prospering at first from buoyant sales of land and largely unaffected by the land wars that constrained development in the North Island. In 1876, when the era of Provincial Government ended, Canterbury was the only New Zealand province not in debt.

Assessment of atmospheric distribution of polychlorinated biphenyls and polycyclic aromatic hydrocarbons using polyparameter model

Results of partial or total destruction of industrial plants, military targets, infrastructure, uncontrolled fires and explosions during the conflict period from 1991 to 1999, at the area of Western Balkans, were large amounts of hazardous organic matter that have been generated and emitted in the environment. In order to assess gas/particle partition of seven EPA polychlorinated biphenyls and sixteen EPA polycyclic aromatic hydrocarbons, twenty air samples have been collected at six urban, industrial and highly contaminated localities in Vojvodina. Hi-Vol methodology has been used for collecting ambiental air samples, that simultaneously collects gaseous and particulate phase with polyurethane foam filters (PUF) and glass fiber filters (GFF). PUF and GFF filters have been analyzed, and concentration levels of gaseous PCBs and PAHs molecules in gaseous and particulate phase were obtained, converted and expressed through fraction of individual compounds sorbed onto particulate phase of the sample, in total detected quantity. Experimentally gained gas/particle partitioning values of PCBs and PAHs molecules have been compared with PP-LFER model estimated values. Significant deviation has been noticed during comparative analysis of estimated polyparameter model values for complete set of seven PCBs congeners. Much better agreement of experimental and estimated values is for polycyclic aromatic hydrocarbons, especially for molecules with four rings. These results are in a good correlation with literature data where polyparameter model has been used for predicting gas/particle partition of studied group of organic molecules.

Potential of small-baseline SAR interferometry for monitoring land subsidence related to underground coal fires: Wuda (Northern China) case study

Uncontrolled coal fires can result in massive surface displacements due to the change in volume of burning coal and thermal effects in the adjacent rock mass; simultaneously, the resultant surface breakings provide greater access to air and water that in turn can aggravate the problem of underground coal seam burning. In this case study, we have investigated the feasibility and potential of detecting the land subsidence accompanying coal fires by means of satellite InSAR observations. Three groups of small-baseline InSAR approaches (PSI, stacking and 2-passDInSAR) were applied to the Wuda coalfield (Northern China) to reveal the spatial and temporal signals of the land subsidence in the areas affected by the coal fires. The interferometric results agree well with GPS observations and coal fire data obtained by field investigation, which demonstrates that the small-baseline InSAR techniques have remarkable potential to detect this land subsidence of interest. In particular, our results show that the development of coal fires can lead to new subsiding areas and also accelerate the ongoing surface subsidence, typically within the areas of mature coal fires, through a comparison of the interferometric observations and the multi-temporal coal fire maps. This timely and reliable information on land subsidence will be useful for the detection and mapping of the coal fire affected regions and thereby assist in fighting and controlling coal seam burning.

Russia counts environmental cost of wildfires

Without better forest management, country can expect further uncontrolled fires in the future.

Sensor-steered fire simulation

A sensor-linked modelling tool for live prediction of uncontrolled compartment fires, K-CRISP, has been developed in order to facilitate emergency response via novel systems such as FireGrid. The modelling strategy is an extension of the Monte-Carlo fire model, CRISP, linking simulations to sensor inputs which controls evolution of the parametric space in which new scenarios are generated, thereby representing real-time “learning” about the fire. CRISP itself is based on a zone model representation of the fire, with linked capabilities for egress modelling and failure prediction for structural members, thus providing a major advantage over more detailed approaches in terms of flexibility and practicality, though with the conventional limitations of zone models. Large numbers of scenarios are required, but computational demands are mitigated to some extent by various procedures to limit the parameters which need to be varied. HPC (high performance computing) resources are exploited in “urgent computing” mode. The approach adopted for steering is shown to be effective in directing the evolution of the fire parameters, thereby driving the fire predictions towards the measurements. Moreover, the availability of probabilistic information in the output assists in providing potential end users with an indication of the likelihood of various hazard scenarios. The best forecasts are those for the immediate future, or for relatively simple fires, with progressively less confidence at longer lead times and in more complex scenarios. Given the uncertainties in real fire development the benefits of more detailed model representations may be marginal and the system developed thus far is considered to be an appropriate engineering approach to the problem, providing information of potential benefit in emergency response.

An ecological study of the plant communities in the proposed Highveld National Park, in the peri-urban area of Potchefstroom, South Africa

The proposed Highveld National Park (HNP) is an area of high conservation value in South Africa, covering approximately 0.03% of the endangered Grassland Biome. The park is situated immediately adjacent to the town of Potchefstroom in the North-West Province. The objective of this study was to identify, classify, describe and map the plant communities in this park. Vegetation sampling was done by means of the Braun-Blanquet method and a total of 88 stratified random relevés were sampled. A numerical classification technique (TWINSPAN) was used and the results were refined by Braun-Blanquet procedures. The final results of the classification procedure were presented in the form of phytosociological tables and, thereafter, nine plant communities were described and mapped. A detrended correspondence analysis confirmed the presence of three structural vegetation units, namely woodland, shrubland and grassland. Differences in floristic composition in the three vegetation units were found to be influenced by environmental factors, such as surface rockiness and altitude. Incidences of harvesting trees for fuel, uncontrolled fires and overgrazing were found to have a significant effect on floristic and structural composition in the HNP. The ecological interpretation derived from this study can therefore be used as a tool for environmental planning and management of this grassland area.Conservation implications: Grasslands are amongst the most threatened and least conserved vegetation biomes in South Africa, with less than 1.3% currently being conserved. The HNP has significant value for biodiversity conservation and the protection of this area will contribute to the preservation of the highly threatened Highveld vegetation types.

Spatial indicators of fire risk in the arid and semi-arid zone of Australia

Abstract Fire plays a role in determining the shape of the earth's ecosystems, impacts socio-economic issues, and influences our climate. In arid and semi-arid Australia (70% of the continent), individual fires frequently exceed 1 million ha, and have collectively burnt up to 9% of the total area in a single year, associated with antecedent periods of above average rainfall which boost the fuel load. People affected by these fires – Federal and State governments, pastoralists, Aboriginal communities, larger towns, conservation park managers and tourist operators – all have different outlooks and priorities about these phenomena. Little objective information about the fire regime and its drivers has been available for this vast area with its very low population density. A predictive understanding of the spatial and temporal pattern of risk of large uncontrollable fires is needed to promote pro-active management. We present a conceptual framework which serves both to summarise existing knowledge and to reduce the complexity for a quantitative statistical analysis. This conceptual framework contains four main groups of independent variables; biomass, curing, ignition source, and fire weather. For these groups of variables we identified direct data sources or spatial surrogates. To quantify different aspects of the fire regime, interpretation of NOAA-AVHRR satellite imagery was employed, which identifies both fire hotspots (FHS) and fire affected area (FAA). For temporal variables, we present a surface displaying relationships for different combinations of lag/phase. This highlights different patterns for each region, and the most appropriate timeframes to use in modelling. Results of exploratory regression analysis in arid and semi-arid Australia show that the strongest influence is exerted by biomass or fuel load. As this is highly dependent on antecedent rainfall, we can anticipate a strong effect of climate change on the fire regime. The strongest combinations of relationships may be used as spatial indicators in the development of long-lead fire risk models for these areas. This can help improve the timing of pro-active strategies to manage fire, and in the allocation of sparse funds and resources. Our analysis has highlighted regional patterns of fire across different land tenures. Heightened awareness of these patterns may encourage a more cooperative and coordinated approach to fire management amongst stakeholders.

Vascular Plant Communities of the Green River Lowlands in Northwestern Illinois

A few high-quality prairies still exist in the sand deposits of the Green River Lowlands. The most extensive remnants are in the Green River State Wildlife Area, Lee County, Illinois. Three upland prairie communities were surveyed; a dry sand prairie dominated by Schizachyrium scoparium, Ambrosia psilostachya, and Amorpha canescens; a dry-mesic sand prairie dominated by Sorghastrum nutans, Schizachyrium scoparium, Antennaria plantaginifolia, and Liatris aspera; and a mesic sand prairie where Sorghastrum nutans and Andropogon gerardii were the dominant grasses, and Parthenium integrifolium, Fragaria virginiana, Liatris pycnostachya, and Euthamia gymnospermoides the common forbs. The lowlands, which included approximately 325 ha, were dominated by the exotic Phalaris arundinacea, but high-quality wet sand prairie, sedge meadow, and marsh communities existed. The wet sand prairies were dominated by Spartina pectinata, Helianthus grosseserratus, and Solidago canadensis; the sedge meadows were dominated by Carex haydenii, Calamagrostis canadensis, and Persicaria coccinea; the marsh communities were divided into distinct vegetation zones. These vegetation zones were surveyed in 2002 and subjected to an extensive uncontrolled fire in 2005. Surveys completed in 2006 and 2007 were used to determine successional changes resulting from the fire. These studies suggested that most communities were returning to the species composition found before the 2005 fire.

Danger of Deploying Weapons and Nuclear Power in Space

Danger of Deploying Weapons and Nuclear Power in Space

Surveys, distribution and current status of the Madagascar Harrier Circus macrosceles in Madagascar

We conducted a 16-month country-wide survey to determine the status of the threatened Madagascar (Marsh) Harrier Circus macrosceles from 2005 to 2006. We searched for harriers in varying habitat types, focusing on marshes, grasslands and savannas, secondary forests and the edge of primary forests. We surveyed 68% of the districts of Madagascar which contain 71 %o f the potential harrier habitat throughout the country. We recorded 80 individuals of this sexually dimorphic raptor; 48 males and 32 females of which 71 were observed during the breeding season (June to December) and nine outside the breeding season (January to May). The Madagascar Harrier has a broad distribution of about 1,000 km north to south (Madagascar is about 1,500 km in length) and east to west, but at extremely low density. Fifty-three (69%) harriers were observed in high elevation marshes and grasslands above 1,100 m in the provinces of Mahajanga and Antananarivo during the breeding season. Three major threats to harriers, all human caused, were identified: the transformation of marshes to rice fields (all nests in lower elevation natural marshes), uncontrolled fires destroying nests (n 5 7 nests lost in 2005 to fires), and human persecution by taking young from nests for a food source and killing adults due to their predatory nature. From our surveys in Madagascar and information from Comoro Islands, we estimate the global population to be 250‐500 individuals suggesting the current Madagascar Harrier population is heading towards endangerment. The survival of the Madagascar Harrier in Madagascar is critically dependent on protecting the remaining natural marshes, which are an extremely limited and critically endangered habitat in Madagascar, with bordering grasslands.

Fissure formation and subsurface subsidence in a coalbed fire

Coalbed fires are uncontrolled subsurface fires that occur around the world. These fires are believed to be significant contributors to annual CO 2 emissions. Although many of these fires have been burning for decades, researchers have only recently begun to investigate physical mechanisms that control fire behavior. One aspect of fire behavior that is poorly characterized is the relationship between subsurface combustion and surface fissures. At the surface above many fires, long, wide fissures are observed. At a coalbed fire near Durango, Colorado, these fissures form systematic orthogonal patterns that align with regional joints in the Upper Cretaceous Fruitland Formation. Understanding the mechanisms that form these fissures is important, as the fissures are believed to play vital roles in sustaining the combustion in the subsurface. In some of the coalbed fire simulation models available today, these fissures are treated as fixed boundary conditions. We argue, using data collected, field observations and simulation result, that there exists a relationship between the location and magnitude of subsidence caused by the fire and the opening of fissures. The results presented suggest that fissures are believed to open when subsurface subsidence gives rise to tensile stresses around pre-existing joints.

A History of Fire Testing: Past, Present, and Future

Abstract This paper discusses the breakthroughs in science and engineering that have brought fire testing technology to its current state of maturity and provides insight into the possibilities for future fire test development by highlighting some areas where advancements are needed. The quest for understanding the properties of fire has been a part of the human experience since the first primitive human viewed the glow of a flame potentially 2.5 million years ago, during the Paleolithic Period. Since these early observations, humankind slowly developed the knowledge to use and understand fire. However, the initial revolution in fire testing did not begin until recently, in the 19th century, when the basic tools were developed that allowed for remote measurement of temperatures and heat flow. Discoveries such as the “thermoelectric effect” and the development of the First Law of Thermodynamics led to the creation of tools for calorimetry providing for the measurement of temperatures and heat flux. The second revolution in measuring and understanding fire occurred in the early 20th century with worldwide recognition that scientifically based fire standards were needed to protect life and property. At the same time, engineering innovation developed electromechanical equipment that could automatically record data measured from fire experiments. This advancement in data recording allowed for the detailed study of measured fire behavior. The third revolution in fire testing (measurement technology) occurred in the last half of the 20th century with the development of affordable digital data logging equipment and computers that enhanced data analysis and the development of scientifically based predictive models. Widespread use of technology and computational methods have opened the theoretical world which provides insight into the subtle features of fire dynamics and provides a means for developing a greater understanding of fire test method performance. Fire measurement technology now has the scientific and computational tools to make significant advancements in the development of fire safety standards. Use of these tools has directed attention to improvements needed in testing for structural fire endurance to enhance fire resistant structural designs. This would include, but not be limited to, advancements in testing of structural components, assemblies, and systems under realistic simulations of fire and load conditions. The objective for these new tests would be to enhance structural performance so that uncontrolled building fires result in burnout without partial or total collapse. Additionally, these fire measurement technologies would also lead to improvements in ignition resistant materials, surface flammability, fire growth, smoke, and toxic gas production that will save lives and reduce the high cost of unwanted fires.

A model for calculating the temperature of aluminium particles ejected from overhead low-voltage lines owing to a short-circuit

Wildfires, which are uncontrolled fires spreading readily over vast areas, are usually the result of human negligence, arson or lightning. There are cases of fires close to electrical distribution lines for which the network has been blamed. In the present paper, the risk of a wildfire breaking out owing to the temperature of molten metal particles that are possibly created on bare conductors of low-voltage networks in short-circuit faults (unless they are interrupted by the protection systems) is examined. Thus, a mathematical model is proposed for the estimated temperature rise of those molten metal particles ejected from bare conductors of low-voltage overhead lines. Moreover, this model can be applied to medium- or high-voltage networks. The model takes into account the weather conditions and particles’ height above the ground. Further, an arithmetic example for an incandescent particle ejected from aluminium conductors of a low-voltage network is given. According to this example, there is no risk of dead leaves or wood catching fire owing to this particle.

Fire-LCA model for environmental decision-making

Fires have been a part of our society both in term of controlled fires, or combustion, for heating purposes and uncontrolled accidental fires. Accidental fires cause a substantial amount of damage both economically and in terms of human lives. However, we need to better understand the relationship between these phenomena, and develop scientifically sound tools for identification of the hazard, the assessment of risk, and the implementation of fire prevention and protection measures. Such work is just beginning within ISO/TC92/SC3 under its mandate to consider not just the local effect of fire effluent on people but also its effect on the environment. A very limited number of papers have focussed on the environmental issues of fires consequently the environmental impact of fires has only recently come under scrutiny. It is, therefore, important to find a method which includes all the impacts of fires. Recently a novel LCA model, the so-called Fire-LCA model, was developed where the environmental effect of fires was incorporated into the overall treatment of the environmental impact of the product under study. The Fire-LCA model is essentially equivalent to a traditional LCA approach with the inclusion of emissions from fires as the most important modification. This model will therefore include modules to describe the fire behavior for the different types of fires. This paper presents an application of the Fire-LCA model to a refinery which is a system with a high level of fire safety.

Practice Advisory for the Prevention and Management of Operating Room Fires

Practice Advisory for the Prevention and Management of Operating Room Fires: An Updated Report by the American Society of Anesthesiologists Task Force on Operating Room Fires Jeffrey Apfelbaum;Robert Caplan;Steven Barker;Richard Connis;Charles Cowles;Jan Ehrenwerth;David Nickinovich;Donna Pritchard;David Roberson;Robert Caplan;Steven Barker;Richard Connis;Charles Cowles;Albert de Richemond;Jan Ehrenwerth;David Nickinovich;Donna Pritchard;David Roberson;Gerald Wolf; Anesthesiology

Sensor-linked fire simulation using a Monte-Carlo approach

This study is aimed at developing a predictive capability for uncontrolled compartment fires which can be “steered” by real-time measurements. This capability is an essential step towards facilitating emergency response via systems such as FireGrid, which seek to provide fire and rescue services with information on the possible evolution of fire incidents on the scene. The strategy proposed to achieve this is a novel coupled simulation tool, based on the Monte-Carlo-based fire model, CRISP, with scenario selection achieved via comparison with (pseudo) sensor inputs. Here, some key aspects of such a system are illustrated and discussed in the context of the detailed measurements obtained in the full-scale fire test undertaken in a furnished apartment at Dalmarnock. The capability of CRISP in reproducing the fire conditions – given knowledge of the approximate heat release rate in the fire – was first verified. It is then shown that continuous selection from amongst a multiplicity of scenarios generated in Monte-Carlo fashion can be achieved, so that the predictions evolve in a way that closely follows the real fire conditions. Whilst the benefits of sensor-steering are already clearly apparent, further improvements will be possible by establishing an appropriate feedback loop between the results assessment and the parametric space in which new fires are generated, perhaps using Bayesian methods. Nevertheless, true predictive capability remains crucially dependent on the sufficient representation in the model of the mechanisms of fire growth, and this must be the focus in achieving better forecasting ability.