Synoptic climatology of lightning-caused forest fires in subalpine and boreal forests

1996 ◽  
Vol 26 (10) ◽  
pp. 1859-1874 ◽  
Author(s):  
C.H. Nash ◽  
E.A. Johnson
Keyword(s):  
High Pressure ◽  
Forest Fires ◽  
Boreal Forests ◽  
Dry Weight ◽  
Weather Conditions ◽  
Synoptic Climatology ◽  
Fuel Moisture ◽  
Fire Occurrence ◽  
Lightning Strikes ◽  
Lightning Fire

The coupling of synoptic scale weather conditions with local scale weather and fuel conditions was examined for 2551 fires and 1 537 624 lightning strikes for the May through August fire seasons in 1988, 1989, 1992, and 1993 in Alberta and Saskatchewan. The probability of lightning fire occurrence (number of fires/number of strikes) is near zero until the Fine Fuel Moisture Code reaches 87 (moisture content of 14% dry weight), after which the probability increases rapidly. Duff Moisture and Drought Codes show less clear increases. In all cases, the probability of fire occurrence was low (the number of strikes greatly exceeded the number of forest fires), suggesting that lightning fire ignition coupled with early spread to detection was an uncommon event. This low probability of fire occurrence even at low fuel moisture may be a result of the arrangement and continuity of fuels in the boreal and subalpine forests. The literature suggests a higher probability of lightning-ignited fires in qualitatively different fuels, e.g., grasslands. The higher probability of fire at lower fuel moistures occurred primarily when high pressure dominated (positive 50-kPa anomaly) for at least 3 days and less than 1.5 mm precipitation occurred. The highest number of lightning strikes and largest number of fires also occurred when high pressure dominated. The high lightning numbers during high pressure systems were logistically related to increasing atmospheric instability (K-index).

Lightning and lightning fire, central cordillera, Canada

2002 ◽  
Vol 11 (1) ◽  
pp. 41 ◽  
Author(s):  
Jack Wierzchowski ◽  
Mark Heathcott ◽  
Michael D. Flannigan
Keyword(s):  
British Columbia ◽  
Forest Fires ◽  
Fire Occurrence ◽  
Fire Weather Index ◽  
Lightning Strikes ◽  
Severity Rating ◽  
Continental Divide ◽  
Significant Difference ◽  
Lightning Discharges ◽  
Lightning Fire

This study examines the influences of fuel, weather and topography on lightning-caused forest fires in portions of southern British Columbia and Alberta, Canada. The results show a significant difference in lightning and lightning-caused fires east and west of the Continental Divide. In British Columbia, on average there was one fire for every 50 lightning discharges whereas in Alberta there was one fire for every 1400 lightning discharges. Elevation, the distribution of lightning strikes, the Daily Severity Rating (a component of the Canadian Forest Fire Weather Index System) and vegetation composition were identified as primary agents controlling lightning fire occurrence. However, the multivariate analysis does suggest that there are other factors influencing fire occurrence other than the biophysical factors we tested. The implications of the lightning and lightning-ignited fires for land managers are discussed.

A lightning fire occurrence model for Ontario

2005 ◽  
Vol 35 (6) ◽  
pp. 1389-1401 ◽  
Author(s):  
B M Wotton ◽  
David L Martell
Keyword(s):  
Forest Floor ◽  
Weather Conditions ◽  
Fire Spread ◽  
Positive Influence ◽  
Lightning Strike ◽  
Organic Layer ◽  
Fire Occurrence ◽  
Lightning Strikes ◽  
Cloud To Ground Lightning ◽  
Lightning Fire

Lightning strike, fire weather, and fire occurrence data were used to model (i) the probability that a lightning strike causes a sustainable ignition on the forest floor and (ii) the probability of an ignition being detected and reported to the fire management agency for each ecoregion in the province of Ontario. An index that tracks duff moisture content in very sheltered areas of a forest stand (near the tree boles) was the most significant predictor in each ignition model. The presence of positive cloud-to-ground lightning strikes was also found to have a significant and positive influence on the probability of ignition in most areas of the province with the exception of the far northwest. Weather conditions following a lightning storm influence the probability that a lightning strike causes a sustainable ignition. Models of the probability of detecting a fire ignited by lightning were also created for each of the ecoregions across Ontario. The form of these models varied somewhat among ecoregions, but contained an indicator of receptive surface fire spread conditions and an indicator of the dryness of the heavier fuels (the organic layer) in the forest floor.

scholarly journals Modeling of wildfire occurrence by using climate data and effect of temperature increments

2020 ◽  
Author(s):  
Amir Hossein Sadat Razavi ◽  
Majid Shafiepour Motlagh ◽  
Alireza Noorpoor ◽  
Amir Houshang Ehsani
Keyword(s):  
Forest Fires ◽  
Boreal Forests ◽  
Environmental Variables ◽  
Temperate Forests ◽  
Forest Type ◽  
Effect Of Temperature ◽  
Transient Temperature ◽  
Fire Occurrence ◽  
Model Output ◽  
Average Temperature

Abstract. Forest fires are assumed as one of the key natural hazards in the globe since it causes great losses in ecology, economy, and human lives; recent fire cases in US and their vast damages are vivid reasons to study the wildfires more deeply One of the basic requirements to manage the threats and protect wildlife is the ability to predict wildfire spots which is necessary to prioritize forest management. In this study, a 25-year period natural wildfire database and a wide array of environmental variables are used to develop an artificial neural network model with the aim of predicting potential fire spots. This study focuses on non-human reasons of wildfires (natural) to compute global warming effects on wildfires. Among the environmental variables, this study shows the significance of temperature for predicting wildfire cases while other parameters are presented in the next study. The study area of this study includes all forest fire cases in united states from 1992 to 2015 excluding tropical forests. The data of eight days including the day fire occurred and 7 previous days are used as input to the model to forecast fire occurrence probability of that day. The climatic inputs are extracted from ECMWF. The inputs of the model are temperature at 2 meter above surface, relative humidity, Total pressure, evaporation, volumetric soil water layer 1, snow melt, Keetch–Byram drought index, total precipitation, wind speed (along U and V direction), and NDVI. The results show there is a transient temperature span for each forest type which acts like a threshold to predict fire occurrence. In Temperate forests, A 0.1-degree Celsius increase in temperature relative to 7-day average temperature before a fire occurrence results in prediction model output of greater than 0.8 for 4.75 % of fire forest cases. In Boreal forests, the model output for temperature increase of less than 1 degree relative to past 7-day average temperature represents no chance of wildfire. But the non-zero fire forest starts at 2 degrees increase of temperature which ends to 2.62 % of fire forest cases with model output of larger than 0.8. It is concluded that other variables except temperature are more determinant to predict wildfires in temperate forests rather than in boreal forests.

A Stochastic Model for the Occurrence of Man-caused Forest Fires

1973 ◽  
Vol 3 (2) ◽  
pp. 282-287 ◽  
Author(s):  
A. A. Cunningham ◽  
D. L. Martell
Keyword(s):  
Stochastic Model ◽  
Forest Fires ◽  
Poisson Model ◽  
Fire Season ◽  
Fuel Moisture ◽  
Fire Occurrence ◽  
Northwestern Ontario

This paper discusses the occurrence of man-caused forest fires during the summer fire season in a section of northwestern Ontario. Fire occurrence is viewed as being a chance process and a stochastic model is developed to describe it. The results of this study indicate that a Poisson model with the average number of fires per day depending on the Fine Fuel Moisture Code is appropriate.

Potential Impacts of Extreme Heat and Bushfires on Dementia

2021 ◽  
Vol 79 (3) ◽  
pp. 969-978
Author(s):  
Taya L. Farugia ◽  
Carla Cuni-Lopez ◽  
Anthony R. White
Keyword(s):  
Rural Communities ◽  
Natural Disasters ◽  
Low Socioeconomic Status ◽  
Forest Fires ◽  
Weather Conditions ◽  
Extreme Weather ◽  
Extreme Heat ◽  
Indigenous Populations ◽  
Future Research ◽  
Diagnosis Of Dementia

Australia often experiences natural disasters and extreme weather conditions such as: flooding, sandstorms, heatwaves, and bushfires (also known as wildfires or forest fires). The proportion of the Australian population aged 65 years and over is increasing, alongside the severity and frequency of extreme weather conditions and natural disasters. Extreme heat can affect the entire population but particularly at the extremes of life, and patients with morbidities. Frequently identified as a vulnerable demographic in natural disasters, there is limited research on older adults and their capacity to deal with extreme heat and bushfires. There is a considerable amount of literature that suggests a significant association between mental disorders such as dementia, and increased vulnerability to extreme heat. The prevalence rate for dementia is estimated at 30%by age 85 years, but there has been limited research on the effects extreme heat and bushfires have on individuals living with dementia. This review explores the differential diagnosis of dementia, the Australian climate, and the potential impact Australia’s extreme heat and bushfires have on individuals from vulnerable communities including low socioeconomic status Indigenous and Non-Indigenous populations living with dementia, in both metropolitan and rural communities. Furthermore, we investigate possible prevention strategies and provide suggestions for future research on the topic of Australian bushfires and heatwaves and their impact on people living with dementia. This paper includes recommendations to ensure rural communities have access to appropriate support services, medical treatment, awareness, and information surrounding dementia.

scholarly journals Tendencies of Fire Development in the Forests of Ukraine

2020 ◽  
Vol 3 (1) ◽  
pp. 106
Author(s):  
Yevhen Melnyk ◽  
Vladimir Voron
Keyword(s):  
Forest Management ◽  
Forest Fires ◽  
Necessary Conditions ◽  
Climatic Conditions ◽  
Anthropogenic Factors ◽  
Burned Area ◽  
Fire Occurrence ◽  
Management Zones ◽  
Wildfire Occurrence ◽  
Management Zone

Preservation and increase of forest area are necessary conditions for the biosphere functioning. Forest ecosystems in most parts of the world are affected by fires. According to the latest data, the forest fire situation has become complicated in Ukraine, and this issue requires ongoing investigation. The aim of the study was to analyse the dynamics of wildfires in Ukrainian forests over recent decades and to assess the complex indicator of wildfire occurrence in various forest management zones and administrative regions. The average annual complex indicator of fire occurrence, in terms of wildfire number and burned area, was studied in detail in the forests of various administrative regions and forest management zones in Ukraine from 1998 to 2017. The results show that fire occurrence in both the number and area of fires can vary significantly in various forest management zones. There is a very noticeable difference in these indicators in some administrative regions within a particular forest management zone. The data show that the number of forest fires depends not only on the natural and climatic conditions of such regions, but also on anthropogenic factors.

Le feu : agent de contrôle des insectes

1994 ◽  
Vol 70 (4) ◽  
pp. 468-472
Author(s):  
M. Martin Dupuis
Keyword(s):  
Forest Fires ◽  
Insect Pests ◽  
Weather Conditions ◽  
Fire Intensity ◽  
Fire Control ◽  
Fire Use ◽  
Wild Fire ◽  
Controlled Burning ◽  
Long Run ◽  
Evolution Understanding

For millenia, fire and insects have played an important role in forested land evolution. Understanding the roles they play can be important in helping us not only to control them, but to use them as an ecological tool. Also, we notice some important interactions between these two agents. As insects affect fire, fire may control insect pests. Controlled burning may provide excellent results, but allows a very slight margin for possible errors. Fire use as an insect mangement tool, requires a very precise and wide knowledge of weather conditions, fire intensity, insect's life cycle, available fuels, and type of ecosystem involved.After a long run of experiences and research, we notice that fire has been and will always be an important factor in equilibrium of some ecosystems. Since wild fire prevention campaigns and the emergence of insecticides, some forests have become excessively vulnerable to insect pests. Proper knowledge, and use of fire control, rather than immediate suppression of forest fires, would allow us to conserve various ecosystems in a healthy balance.

Efficient Solar Desalination System Using Humidification/Dehumidification Process

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Adel M. Abdel Dayem
Keyword(s):  
High Pressure ◽  
Heat Source ◽  
System Performance ◽  
Salt Water ◽  
Weather Conditions ◽  
Water Production ◽  
High Pressure Pump ◽  
Solar Desalination ◽  
Flat Plate Collector ◽  
The Cost

An innovative solar desalination system is successfully designed, manufactured, and experimentally tested at Makkah, 21.4 degN. The system consists of 1.15 m2 flat-plate collector as a heat source and a desalination unit. The unit is about 400 l vertical cylindrical insulated tank. It includes storage, evaporator, and condenser of hot salt-water that is fed from the collector. The heated water in the collector is raised naturally to the unit bottom at which it is used as storage. A high pressure pump is used to inject the water vertically up through 1-mm three nozzles inside the unit. The hot salt-water is atomized inside the unit where the produced vapor is condensed on the inner surfaces of the unit outer walls to outside. The system was experimentally tested under different weather conditions. It is obtained that the system can produce about 9 l a day per quadratic meter of collector surface area. By that it can produce about 1.6 l/kWh of solar energy. Moreover, the water temperature has a great effect on the system performance although the scaling possibility is becoming significant. By that way the cost of a liter water production is relatively high and is obtained as 0.5 US$.

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