scholarly journals Attribution of the Australian bushfire risk to anthropogenic climate change

2021 ◽  
Vol 21 (3) ◽  
pp. 941-960
Author(s):  
Geert Jan van Oldenborgh ◽  
Folmer Krikken ◽  
Sophie Lewis ◽  
Nicholas J. Leach ◽  
Flavio Lehner ◽  
...  
Keyword(s):  
Climate Change ◽  
Climate Models ◽  
Southern Annular Mode ◽  
Warming Trend ◽  
Anthropogenic Climate Change ◽  
Fire Season ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index

Abstract. Disastrous bushfires during the last months of 2019 and January 2020 affected Australia, raising the question to what extent the risk of these fires was exacerbated by anthropogenic climate change. To answer the question for southeastern Australia, where fires were particularly severe, affecting people and ecosystems, we use a physically based index of fire weather, the Fire Weather Index; long-term observations of heat and drought; and 11 large ensembles of state-of-the-art climate models. We find large trends in the Fire Weather Index in the fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) Atmospheric Reanalysis (ERA5) since 1979 and a smaller but significant increase by at least 30 % in the models. Therefore, we find that climate change has induced a higher weather-induced risk of such an extreme fire season. This trend is mainly driven by the increase of temperature extremes. In agreement with previous analyses we find that heat extremes have become more likely by at least a factor of 2 due to the long-term warming trend. However, current climate models overestimate variability and tend to underestimate the long-term trend in these extremes, so the true change in the likelihood of extreme heat could be larger, suggesting that the attribution of the increased fire weather risk is a conservative estimate. We do not find an attributable trend in either extreme annual drought or the driest month of the fire season, September–February. The observations, however, show a weak drying trend in the annual mean. For the 2019/20 season more than half of the July–December drought was driven by record excursions of the Indian Ocean Dipole and Southern Annular Mode, factors which are included in the analysis here. The study reveals the complexity of the 2019/20 bushfire event, with some but not all drivers showing an imprint of anthropogenic climate change. Finally, the study concludes with a qualitative review of various vulnerability and exposure factors that each play a role, along with the hazard in increasing or decreasing the overall impact of the bushfires.

scholarly journals Attribution of the Australian bushfire risk to anthropogenic climate change

2020 ◽  
Author(s):  
Geert Jan van Oldenborgh ◽  
Folmer Krikken ◽  
Sophie Lewis ◽  
Nicholas J. Leach ◽  
Flavio Lehner ◽  
...  
Keyword(s):  
Climate Change ◽  
Climate Models ◽  
Southern Annular Mode ◽  
Warming Trend ◽  
Anthropogenic Climate Change ◽  
Fire Season ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index

Abstract. Disastrous bushfires during the last months of 2019 and January 2020 affected Australia, raising the question to what extent the risk of these fires was exacerbated by anthropogenic climate change. To answer the question for southeastern Australia, where fires were particularly severe, affecting people and ecosystems, we use a physically-based index of fire weather, the Fire Weather Index, long-term observations of heat and drought, and eleven large ensembles of state-of-the-art climate models. In agreement with previous analyses we find that heat extremes have become more likely by at least a factor two due to the long-term warming trend. However, current climate models overestimate variability and tend to underestimate the long-term trend in these extremes, so the true change in the likelihood of extreme heat could be larger. We do not find an attributable trend in either extreme annual drought or the driest month of the fire season September–February. The observations, however, show a weak drying trend in the annual mean. Finally, we find large trends in the Fire Weather Index in the ERA5 reanalysis, and a smaller but significant increase by at least 30 % in the models. The trend is mainly driven by the increase of temperature extremes and hence also likely underestimated. For the 2019/20 season more than half of the July–December drought was driven by record excursions of the Indian Ocean dipole and Southern Annular Mode. These factors are included in the analysis. The study reveals the complexity of the 2019/20 bushfire event, with some, but not all drivers showing an imprint of anthropogenic climate change.

Fire-Weather Index and Climate Change

2020 ◽  
pp. 45-63 ◽  
Author(s):  
Zuzana Hubnerova ◽  
Sylvia Esterby ◽  
Steve Taylor
Keyword(s):  
Climate Change ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index

Fire weather index system components for large fires in the Canadian boreal forest

2004 ◽  
Vol 13 (4) ◽  
pp. 391 ◽  
Author(s):  
B. D. Amiro ◽  
K. A. Logan ◽  
B. M. Wotton ◽  
M. D. Flannigan ◽  
J. B. Todd ◽  
...  
Keyword(s):  
Weather Conditions ◽  
Fire Season ◽  
Fire Weather ◽  
Fuel Moisture ◽  
Weather Index ◽  
Fire Weather Index ◽  
System Parameters ◽  
System Components ◽  
Large Fires ◽  
Canadian Boreal Forest

Canadian Fire Weather Index (FWI) System components and head fire intensities were calculated for fires greater than 2 km2 in size for the boreal and taiga ecozones of Canada from 1959 to 1999. The highest noon-hour values were analysed that occurred during the first 21 days of each of 9333 fires. Depending on ecozone, the means of the FWI System parameters ranged from: fine fuel moisture code (FFMC), 90 to 92 (82 to 96 for individual fires); duff moisture code (DMC), 38 to 78 (10 to 140 for individual fires); drought code (DC), 210 to 372 (50 to 600 for individual fires); and fire weather index, 20 to 33 (5 to 60 for individual fires). Fine fuel moisture code decreased, DMC had a mid-season peak, and DC increased through the fire season. Mean head fire intensities ranged from 10 to 28 MW m−1 in the boreal spruce fuel type, showing that most large fires exhibit crown fire behaviour. Intensities of individual fires can exceed 60 MW m−1. Most FWI System parameters did not show trends over the 41-year period because of large inter-annual variability. A changing climate is expected to create future weather conditions more conducive to fire throughout much of Canada but clear changes have not yet occurred.

Wildfires and the Canadian Forest Fire Weather Index system for the Daxing'anling region of China

2011 ◽  
Vol 20 (8) ◽  
pp. 963 ◽  
Author(s):  
Xiaorui Tian ◽  
Douglas J. McRae ◽  
Jizhong Jin ◽  
Lifu Shu ◽  
Fengjun Zhao ◽  
...  
Keyword(s):  
Forest Fire ◽  
Forest Fires ◽  
Coniferous Forest ◽  
Northern China ◽  
Fire Danger ◽  
Fire Season ◽  
Fire Weather ◽  
Burnt Area ◽  
Weather Index ◽  
Fire Weather Index

The Canadian Forest Fire Weather Index (FWI) system was evaluated for the Daxing'anling region of northern China for the 1987–2006 fire seasons. The FWI system reflected the regional fire danger and could be effectively used there in wildfire management. The various FWI system components were classified into classes (i.e. low to extreme) for fire conditions found in the region. A total of 81.1% of the fires occurred in the high, very high and extreme fire danger classes, in which 73.9% of the fires occurred in the spring (0.1, 9.5, 33.3 and 33.1% in March, April, May and June). Large wildfires greater than 200 ha in area (16.7% of the total) burnt 99.2% of the total burnt area. Lightning was the main ignition source for 57.1% of the total fires. Result show that forest fires mainly occurred in deciduous coniferous forest (61.3%), grass (23.9%) and deciduous broad leaved forest (8.0%). A bimodal fire season was detected, with peaks in May and October. The components of FWI system were good indicators of fire danger in the Daxing'anling region of China and could be used to build a working fire danger rating system for the region.

scholarly journals A high-resolution reanalysis of global fire weather from 1979 to 2018 – Overwintering the Drought Code

2020 ◽  
Author(s):  
Megan McElhinny ◽  
Justin F. Beckers ◽  
Chelene Hanes ◽  
Mike Flannigan ◽  
Piyush Jain
Keyword(s):  
High Resolution ◽  
Fire Behavior ◽  
Fire Season ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index ◽  
Start Up ◽  
System Calculation ◽  
Second Procedure ◽  
Temporal Coverage

Abstract. We present a global high-resolution calculation of the Canadian Fire Weather Index (FWI) System Indices using surface meteorology from the ERA5-HRS reanalysis for 1979–2018. ERA5-HRS represents an improved dataset compared to several other reanalyses in terms of accuracy, as well as spatial and temporal coverage. The FWI calculation is performed using two different procedures for setting the start-up value of the Drought Code (DC) at the beginning of the fire season. The first procedure, which accounts for the effects of inter-seasonal drought, overwinters the DC by adjusting the fall DC value with a fraction of accumulated overwinter precipitation. The second procedure sets the DC to its default start-up value (i.e. 15) at the start of each fire season. We validate the FWI values over Canada using station observations from Environment and Climate Change Canada and find generally good agreement (mean Spearman correlation of 0.77). We also show that significant differences in early season DC and FWI values can occur when the FWI System calculation is started using the overwintered versus default DC values, as is highlighted by an example from 2016 over North America. The FWI System moisture codes and fire behavior indices are made available for both versions of the calculation at https://doi.org/10.5281/zenodo.3626193 (McElhinny et al., 2020), although we recommend using codes and indices calculated with the overwintered DC, unless specific research requirements dictate otherwise.

Relationships between the moisture content of fine woody fuels in lodgepole pine slash and the Fine Fuel Moisture Code of the Canadian Forest Fire Weather Index System

1988 ◽  
Vol 18 (1) ◽  
pp. 128-131 ◽  
Author(s):  
R. Trowbridge ◽  
M. C. Feller
Keyword(s):  
Moisture Content ◽  
Forest Fire ◽  
Index System ◽  
Lodgepole Pine ◽  
Fire Season ◽  
Fire Weather ◽  
Fuel Moisture ◽  
Weather Index ◽  
Fire Weather Index ◽  
Moisture Contents

Unsuccessful attempts to ignite slash resulting from the mechanical knocking down of lodgepole pine in west central British Columbia led to a short-term investigation of the relationship between the Fine Fuel Moisture Code of the Canadian Forest Fire Weather Index System and the moisture content of various fine fuel components <1 cm in diameter. Of the types of fuel sampled, the moisture contents of B.C. Forest Service fuel moisture sticks and aged slash were similar to, and well correlated (r = 0.79 and 0.81, respectively) with, the equivalent moisture content calculated from the Fine Fuel Moisture Code. The Fine Fuel Moisture Code was not designed to relate to the moisture content of uncured fuels. Thus, the moisture contents of fresh living slash (material from knocked down trees still attached to living roots) and of fresh dead slash (material unattached to living trees that had not yet experienced a complete fire season in which to fully cure) were poorly correlated with moisture content (r = 0.16 and 0.42, respectively). The moisture content of the progressively curing, needle-bearing fresh dead slash was relatively high at the beginning of the fire season, but became similar to the moisture content during the first half of July. This suggests that the Fine Fuel Moisture Code can also be used to predict the moisture content of such fine slash after these fuels have cured for approximately 3 months during the snow-free period.

scholarly journals Projection of Forest Fire Danger due to Climate Change in the French Mediterranean Region

2019 ◽  
Vol 11 (16) ◽  
pp. 4284 ◽  
Author(s):  
Vassiliki Varela ◽  
Diamando Vlachogiannis ◽  
Athanasios Sfetsos ◽  
Stelios Karozis ◽  
Nadia Politi ◽  
...  
Keyword(s):  
Climate Change ◽  
Forest Fire ◽  
Fire Severity ◽  
Fire Danger ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index ◽  
Future Time Period ◽  
Forest Fire Danger ◽  
Decision Support Process

Fire occurrence and behaviour in Mediterranean-type ecosystems strongly depend on the air temperature and wind conditions, the amount of fuel load and the drought conditions that drastically increase flammability, particularly during the summer period. In order to study the fire danger due to climate change for these ecosystems, the meteorologically based Fire Weather Index (FWI) can be used. The Fire Weather Index (FWI) system, which is part of the Canadian Forest Fire Danger Rating System (CFFDRS), has been validated and recognized worldwide as one of the most trusted and important indicators for meteorological fire danger mapping. A number of FWI system components (Fire Weather Index, Drought Code, Initial Spread Index and Fire Severity Rating) were estimated and analysed in the current study for the Mediterranean area of France. Daily raster-based data-sets for the fire seasons (1st May–31st October) of a historic and a future time period were created for the study area based on representative concentration pathway (RCP) 4.5 and RCP 8.5 scenarios, outputs of CNRM-SMHI and MPI-SMHI climate models. GIS spatial analyses were applied on the series of the derived daily raster maps in order to provide a number of output maps for the study area. The results portray various levels of changes in fire danger, in the near future, according to the examined indices. Number of days with high and very high FWI values were found to be doubled compared to the historical period, in particular in areas of the Provence-Alpes-Côte d’Azur (PACA) region and Corsica. The areas with high Initial Spread Index and Seasonal Spread Index values increased as well, forming compact zones of high fire danger in the southern part of the study area, while the Drought Code index did not show remarkable changes. The current study on the evolution of spatial and temporal distribution of forest fire danger due to climate change can provide important knowledge to the decision support process for prevention and management policies of forest fires both at a national and EU level.

Projections of the Fire Weather Index (FWI) using CORDEX-CORE simulations

2021 ◽  
Author(s):  
Francesca Raffaele ◽  
Rita Nogherotto
Keyword(s):  
Mediterranean Basin ◽  
Climate Models ◽  
Regional Climate ◽  
Time Slice ◽  
Fire Weather ◽  
Climate Scenarios ◽  
Future Time ◽  
Weather Index ◽  
Fire Weather Index ◽  
The Mediterranean Basin

&lt;p&gt;Changes in global fire activity are influenced by a multitude of factors including land-cover change, policies, and climatic conditions. In this study we focus our attention on climate, investigating how relative humidity, wind, temperature and precipitation changes can act together in fire danger. Within the CORDEX-CORE initiative, two regional climate models (RCM) have been used&amp;#160;at&amp;#160; 0.22&amp;#176; resolution and to downscale 3 global climate models (GCMs) from the CMIP5 project. The analysis is carried out over 9 CORDEX domains for two climate scenarios namely the RCP2.6 and the RCP8.5. The high resolution regional climate simulations have been used to evaluate changes in the fire danger by means of the Fire Weather Index (FWI).&amp;#160; The attention is focused on the Mediterranean Basin and in South America, as well as in Australia and in the North America domains. Both climate scenarios show similar projections for the near future time slice (2031-2050) with an increase of the index in those areas that are already affected by seasonal fires such as Spain and Southern Italy for the Mediterranean Basin and the central band of Brazil. For the future time slice (2081-2100) the signal increases, and it is stronger for the RCP8.5 scenario in all regions as expected.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

A Comparison of Fire-Weather Severity in Northern Alberta During the 1980 and 1981 Fire Seasons

1986 ◽  
Vol 62 (6) ◽  
pp. 507-513 ◽  
Author(s):  
D. A. Harvey ◽  
M. E. Alexander ◽  
B. Janz
Keyword(s):  
Fire Danger ◽  
Fire Season ◽  
Fire Weather ◽  
Weather Index ◽  
Fire Weather Index ◽  
Severity Rating ◽  
Total Potential ◽  
Forest Fire Danger ◽  
Objective Basis ◽  
Northern Alberta

The burning potential of two major fire seasons in northern Alberta is evaluated with the use of the Canadian Forest Fire Danger Rating System (CFFDRS). Fire danger class frequency and severity ratings based on the Fire Weather Index (FWI) component in the CFFDRS were utilized in the evaluation. Daily fire-danger reports from 16 selected fire weather stations distributed throughout the northern half of the province provided the basis for the analysis. Although the Seasonal Severity Rating (SSR) for 1981 was slightly higher (SSR = 3.1) than that of 1980 (SSR = 2.5), the area burned in 1981 was about double that of the previous year. The period of critical fire weather began early in the 1980 fire season and prior to the normal summer lightning pattern, whereas in 1981 it occurred during the latter half of the fire season and coincided with the majority of the lightning incidence. FWI severity ratings were not designed to portray a complete picture of the total potential fire containment job but rather to provide an objective basis on which to compare the severity of one season's fire weather with another. Key words: Fire Weather index, fire season seventy rating, critical fire weather, lightning occurrence, northern Alberta.

Sign in / Sign up

Export Citation Format

Share Document