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Climate Futures for Tasmania
Discussion document:
Implications for fire danger in bushfire prone areas of Tasmania
May 2010
Climate Futures for Tasmania – Discussion document:
Implications for fire danger in bushfire prone areas of Tasmania
For restricted circulation only Compiled by Climate Futures for Tasmania Page 2 of 21 22 June 2010
Discussion document
Implications for fire danger in bushfire prone areas of Tasmania
White CJ, Fox-Hughes P, Grose MR, Corney S, Bennett JC, Holz GK, Gaynor S and Bindoff NL
June 2010
Frequently used acronyms
Australian Water Availability Project AWAP
IPCC Fourth Assessment Report AR4
Conformal Cubic Atmospheric Model CCAM
Global Climate Model GCM
Intergovernmental Panel on Climate Change IPCC
Climate Futures for Tasmania – Discussion document:
Implications for fire danger in bushfire prone areas of Tasmania
For restricted circulation only Compiled by Climate Futures for Tasmania Page 3 of 21 22 June 2010
Table of Contents
1 Introduction 4 1.1 Purpose of this document 4 1.2 Conditions of release 4
2 Bushfire danger in Tasmania 4 2.1 Calculation of fire danger 4 2.2 Fire danger in Tasmania 5 2.3 Forecasting fire danger 7 2.4 Seasonal forecasting 10
3 Future bushfire weather 10 3.1 The Climate Futures for Tasmania project 10 3.2 Using the climate projections 11 3.3 Future projections relevant to bushfire weather 12
4 References 20
Disclaimer and Conditions of Use
The Climate Futures for Tasmania project has provided analysed data from climate simulations in the discussion document 'Implications for fire danger in bushfire prone areas of Tasmania' to Sue Stack of the Bushfire CRC at the University of Tasmania. The generation of the climate data was commissioned by the Antarctic Climate & Ecosystems Cooperative Research Centre (ACE CRC) as part of its Climate Futures for Tasmania project.
The analysed data provided to the Bushfire CRC is of a preliminary nature. The analysed data has been released early for the purpose of using the modelling outputs for complementary research and student course material. This analysed data is yet to be peer reviewed, confirmed or published, and therefore should not be taken as final. Any copies, reproductions, developments or conclusions based on the Climate Futures for Tasmania modelling outputs and/or analysed data must not be published prior to the Climate Futures for Tasmania Extreme Events Technical Report, which is due for release later in 2010. This discussion paper should not be circulated beyond the participants of the Planning and Managing for Climate Change (KGA518) course at the University of Tasmania.
The Climate Futures for Tasmania datasets contain climate simulations based on computer modelling. Models involve simplifications of real physical processes. Accordingly, no responsibility will be accepted by the ACE CRC or the Climate Futures for Tasmania project for the accuracy of simulations or projections inferred from the datasets or for any person's interpretations, deductions, conclusions or actions in reliance of the climate simulations.
Climate Futures for Tasmania – Discussion document:
Implications for fire danger in bushfire prone areas of Tasmania
For restricted circulation only Compiled by Climate Futures for Tasmania Page 4 of 21 22 June 2010
1 Introduction
1.1 Purpose of this document
This Discussion Document was prepared as supporting documentation for the Natural
Disaster Resilience Program (NDRP) application titled ‘Impact of Climate Change on fire risk,
natural hazards, and policy responses’ proposed by the Antarctic Climate and Ecosystems
Cooperative Research Centre (ACE CRC). The discussion paper was later supplied to Sue
Stack at the Bushfire Cooperative Research Centre for use as teaching material for the
Planning and Managing for Climate Change course (KGA518).
It contains observations from the Bureau of Meteorology and an early release of preliminary
projections from the Climate Futures for Tasmania project to provide information on the
potential and capacity of the research conclusions for the assessment of bushfire risk in
Tasmania. The information provided relates to the current drivers of bushfire weather
conditions and the likely impacts of climate change on the occurrence of bushfire weather.
This document contains excerpts from the Bureau of Meteorology and three technical reports
from the Climate Futures for Tasmania project (Corney et al., 2010; Grose et al., 2010;
White et al., 2010), all of which are currently in the scientific peer review process.
1.2 Conditions of release
The results from the Climate Futures for Tasmania research contained in this Discussion
Document are yet to be published; therefore, circulation of this document is restricted. See
disclaimer at front of the document.
2 Bushfire danger in Tasmania
2.1 Calculation of fire danger
A number of measures of “fire danger” have been developed over several decades, in fire-
prone areas around the world. In much of Australia, and in particular Tasmania, the Mark V
McArthur forest fire danger meter (McArthur, 1967; Noble et al., 1980) is used operationally
for the prediction of the difficulty of suppression of any fires that are ignited. The meter uses
inputs of air temperature, relative humidity and wind speed, together with a measure of fuel
dryness, to calculate a “forest fire danger index”, FFDI, value. It is well recognized that the
index is limited, but proposed alternatives have not proven popular to date with land and fire
managers.
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The fuel dryness is included in FFDI calculation through a ‘drought factor’ that combines the
effects of soil moisture deficit and recent precipitation on fuel moisture. The meter was
recently modified to ensure a smooth transition between fuel moisture categories (Griffiths,
1998; 1999). In Tasmania, for many years the Mount Soil Dryness Index (Mount, 1972) has
been used as a ground moisture input (or indicator of longer term drying) to modulate the
drought factor input to the fire danger index. A number of fire danger rating categories are
defined from ranges of FFDI values. Following the Victorian Bushfire Royal Commission
Interim Report of 2009, these have been reassigned as: ‘Low-Moderate’ 0-11, ‘High’ 12-24,
‘Very High’ 25-49, ‘Severe’ 50-74, ‘Extreme’ 75-99 and ‘Catastrophic’ 100+.
2.2 Fire danger in Tasmania
High quality datasets of weather parameters have been used in a number of studies to assess
the fire danger in Tasmania (e.g. Lucas, 2006; Fox-Hughes, 2008). It is generally recognized
that southeast Tasmania, including the Hobart area, is subject to the highest fire danger in
the state. Figure 1 shows a contoured map of (approximate) boundaries of fire danger
recorded in the last decade in Tasmania. The data is constructed from Automatic Weather
Station records and the manual stations of Ross and Melton Mowbray (which record data
much less frequently than AWS, but are in otherwise data-sparse areas), using wind speeds
averaged over 10 minutes. Southeast Tasmania has been subject to what is currently
referred to as ‘Catastrophic’ fire danger on several occasions in the last ten years, while some
other parts of the state, particularly about the north coast and highlands, have never
recorded more than ‘Very High’ fire danger.
Climate Futures for Tasmania – Discussion document:
Implications for fire danger in bushfire prone areas of Tasmania
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Figure 1. Maximum fire danger recorded from (mostly) Automatic
Weather Stations in Tasmania in the last decade. “Catastrophic” fire
danger has occurred on a number of occasions in southeast TAS. In the past, summer and autumn was regarded as the peak fire danger period in Tasmania
(Luke and McArthur, 1978). Recently, however, it has become clear that a secondary peak of
fire danger has developed in springtime, at least in the southeast and east (Fox-Hughes,
2008). Figure 2 shows the increase over the last several decades in the number of serious
springtime fire danger episodes. This change fits within a broader, more gradual, increase in
recorded fire danger across all seasons.
Hobart: Number of springtime Very High FFDI >=40 events by decade
0
2
4
6
8
10
12
14
1947-56 57-66 67-76 77-86 87-96 97-06
Decade
Nu
mb
er o
f ev
ents
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Hobart Airport Seasonal Percentile FFDI
0
5
10
15
20
25
30
35
40
1950 1960 1970 1980 1990 2000 2010
P95
P99
P995
Linear (P995)
Linear (P99)
Linear (P95)
Figure 2. Decadal variation in the number of fire danger events where the FFDI at
Hobart has reached at least 40.
Figure 3, for example, displays the 95th, 99th and 99.5th percentile values of FFDI at Hobart
Airport between 1960 and 2006, using all data across all seasons. It is clear that there is an
increasing trend, and that the increase is faster at the more extreme end of the data. This is
consistent with other research (e.g. Alexander et al., 2007) detailing a more rapid increase in
extreme events compared to the average.
Figure 3. 95th (blue) 99th (pink) and 99.5th (yellow) percentiles of fire danger at
Hobart Airport between 1960 and 2006, together with linear regression lines in
corresponding colours.
2.3 Forecasting fire danger
Bad fire danger days typically occur in southeastern Tasmania when a high pressure system
is located in the Tasman Sea, and an approaching cold front or trough of low pressure directs
Climate Futures for Tasmania – Discussion document:
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a north to northwesterly airstream over the state (Brotak and Reifsnyder, 1977; Marsh,
1987). The airstream originates over inland continental Australia and is usually hot and dry
during the warmer months. A foehn effect acts to further warm air as it descends from the
Central Highlands of Tasmania into the southeast (Sharples et al., 2010).
On a routine basis during the warmer months, forecasters employ a variety of conceptual and
numerical weather models to predict fire danger in Tasmania. Numerical weather model data
is used directly to assess likely weather, however, fields of fire danger can be created to
provide a summary of expected higher fire danger (Finkele et al., 2006). U.S. studies (e.g.
Hoadley et al., 2004) and local operational experience have suggested that such techniques
can often pick trends and regional variations in fire danger quite well, but often miss peaks
and extreme values. Figure 4 provides an example of a forecast successful in representing
the area of elevated fire danger, together with the trends during the day, but which under
forecast the extreme values recorded on that day.
Recent research has suggested useful forecasting tools on days of anticipated fire danger.
For example, Mills (2002) examined the structure of cool changes propagating through
coastal areas of southeastern Australia, and looked in detail at a Hobart event that had
significant aviation, as well as fire weather, consequences (Mills and Pendlebury, 2003). An
understanding of the structure of the wind field on days of elevated fire danger is critically
important for fire management, and this research allowed forecasters to appreciate the
complex interaction between cool changes and the land-sea interface.
Climate Futures for Tasmania – Discussion document:
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Hobart Airport Forest Fire Danger 7 November 2002
-20
-10
0
10
20
30
40
50
60
70
80
90
6:00
7:00
8:00
9:00
10:0
011
:00
12:0
013
:00
13:3
014
:00
15:0
015
:30
16:1
316
:58
17:5
218
:37
19:1
019
:43
20:1
520
:45
21:3
0
0
20
40
60
80
100
120
140
160
temp
dewpt
windspeed
ffdi
Figure 4. Fourteen hour forecast of fire danger for Tasmania on 12 October
2006 from the Bureau of Meteorology operational mesoscale numerical
weather model. The forecast successfully indicated the area of elevated fire
danger, but values of fire danger were under forecast.
Satellite data has for many years been invaluable in weather forecasting. Increasingly,
information from the 6.7μm water vapour band is being used to assess the likelihood of rapid
falls in relative humidity (and increases in fire danger) associated with the approach of a cold
front (Mills, 2008; Zimet et al., 2007). Dry air from high in the atmosphere can descend
under the influence of jet stream circulations to mid- to lower layers where thermal mixing or
mountain wave activity can direct it to the surface. A number of extreme Tasmanian fire
weather events bear the signature of such a process, including some currently being studied.
Figure 5 plots individual weather parameters together with calculated FFDI at Hobart Airport
for one such event, while Figure 6 displays a water vapour image from a U.S. GOES satellite
earlier in the afternoon. A filament of low moisture air from close to the tropopause (grey
shade) crossed Tasmania a short time before the surface weather parameters abruptly
changed to cause an upward spike in the fire danger experienced in southeast Tasmania.
Figure 5. Plot of weather and fire danger from Hobart Airport 7 November 2002. Note the spike in
fire danger as dewpoint temperature (a measure of moisture content of the air) drops and wind
increases in the early evening.
Climate Futures for Tasmania – Discussion document:
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Figure 6. Water vapour image from the afternoon of 7 November 2002. A “dry slot” crosses
Tasmania shortly ahead of the surface increase in fire danger.
2.4 Seasonal forecasting
Forecasting for an approaching fire season currently relies on assessments of likely above or
below average precipitation during the fire season. These in turn are predicated on
relationships established between, particularly, El Nino-Southern Oscillation trends and those
of the Indian Ocean Dipole. There has been some research that directly relates ENSO and
IOD trends to interannual variations in Tasmanian fire weather (Williams and Karoly, 1999;
Nicholls and Lucas, 2007) but more remains to be done.
3 Future bushfire weather
3.1 The Climate Futures for Tasmania project
Climate change is a global phenomenon, however the impacts are not evenly distributed over
the globe. Global climate models, due to their coarse resolution, are unable tell us much
about the local impacts of climate change. Dynamical downscaling of global climate models is
a way of providing detailed information of the local variations and impacts of projected
changes. The Climate Futures for Tasmania project uses CSIRO’s Conformal Cubic
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Atmospheric Model (CCAM) to dynamically downscale IPCC global climate model outputs to
produce fine-scale climate projections for Tasmania to 2100.
The Climate Futures for Tasmania presents a set of six model simulations dynamically
downscaled for Tasmania under two IPCC emission scenarios: one high (A2) and one low
(B1). A single model simulation gives a single projection of a climate scenario, analogous to a
single iteration of an experiment. More model simulations give further realisations of that
experiment and this helps to give an estimate of the range of possible outcomes for a given
emission scenario and to quantify the spread of the projected climate. For this reason, the
project has undertaken the maximum number of model simulations that computation time
allowed: the downscaling of six Global Climate Models (CSIRO-Mk3.5, GFDL-CM2.0, GFDL-
CM2.1, MPI/ECHAM5, UKMO-HadCM3 and MIROC3.2(medres)) for both the A2 and B1
scenarios. These six simulations were chosen for their performance in simulating the
Australian region (see Corney et al. (2010) for more detail). The benefit of multi-model
ensemble simulations is that they generally provide more robust information than simulations
from any single model (IPCC, 2007). Since the main focus in this special synopsis is the
change to the mean state of the general climate, the focus will be on the ensemble of these
models rather than any one particular simulation.
Climate Futures for Tasmania is a jointly funded, collaborative research project that has
generated improved climate change information for Tasmania out to 2100. It is a project of
the Antarctic Climate & Ecosystems Cooperative Research Centre (ACE CRC), supported by
funds from the Tasmanian State Government, the Federal Government and Hydro Tasmania,
and in-kind research from CSIRO Division of Marine and Atmospheric Research; Hydro
Tasmania; Department of Primary Industries, Parks Water and the Environment (Tasmanian
Government); University of Tasmania, through the Tasmanian Partnership for Advanced
Computing (TPAC) and the Tasmanian Institute of Agricultural Research (TIAR); Geoscience
Australia; and the Bureau of Meteorology.
3.2 Using the climate projections
Tasmania is unusual in its global perspective with regard to climate change. It lies on the
border between two regions: one region to the north where most global climate models show
a drying trend and one region to the south where most show a wetting trend. These factors
make Tasmania a difficult region to project climate change using just global climate models.
Furthermore, Tasmania’s topography is highly variable, resulting in a spatially varied climate
across the island, ranging from an annual precipitation of 500 mm on the drier east coast to
more than 3000 mm on the mountainous west coast. This level of spatial variability cannot
be simulated in global climate models.
The dynamical downscaling of global climate models for Tasmania is a way of incorporating
the uniqueness of Tasmania’s complex topography and maritime influenced climate to
provide a clearer picture of regional variations and impacts of projected climate change.
Climate Futures for Tasmania – Discussion document:
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However, the models are not perfect. They do not, and cannot, simulate every aspect of the
climate of Tasmania. However, climate models can reproduce the central aspects of the
patterns of variability and the weather system that describes the overall climate and as such,
they are our best tool for assessing potential changes in the future climate. The downscaled
models have demonstrated a high level of skill in reproducing the recent climate of Tasmania
across a range of climate variables. This gives us confidence that the models are able to
provide realistic projections of the Tasmanian climate out to 2100.
3.3 Future projections relevant to bushfire weather
Through the Climate Futures for Tasmania project, numerous analyses have been undertaken
that assess the likely future changes to several climate variables that are relevant to the
calculation of bushfire weather. These include temperature, wind speed, relative humidity,
pressure, precipitation and soil moisture. Although a direct calculation of future bushfire risk
has not been undertaken as part of the Climate Futures for Tasmania project (e.g. FFDI), the
following preliminary results may be used to infer possible future changes to bushfire risk in
Tasmania. What is clear from these results is the requirement for a full bushfire risk analysis
in a future changing climate.
3.3.1 Temperature
Under the high IPCC emission scenario (A2), the average temperature change over Tasmania
is projected to be 2.9 °C over the 21st century. The six models used show a range of
temperature rise from 2.6 °C to 3.3 °C. The projections suggest temperature increases are
smaller in the early part of the century, but the rate of change accelerates towards the end of
the century (Figure 7). The spatial pattern of temperature rise is quite uniform across
Tasmania, with a different pattern emerging in the different seasons (Figure 8). Under the
low IPCC emission scenario (B1), the projections for temperature suggest an average rise of
1.6 °C. The six models used show a range of temperature rise for the B1 scenario from
1.3 °C to 2.0 °C. Both the IPCC scenarios give a similar climate response for the first half of
the century and the difference between the scenarios becomes noticeable around the middle
of the century. After 2070, the spread of the six A2 simulations is higher than the spread of
the six B1 simulations (Figure 7).
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Figure 7. Projected mean temperature anomalies to 2100 relative to the 1961-1990 baseline.
Smoothed time series (11-year running mean) of Tasmanian mean daily mean temperature in
model projections under two emission scenarios, A2 (red) and B1 (blue) IPCC SRES
(Nakicenovic, 2000) compared with observed temperature for the past century (black line)
Bureau of Meteorology high quality temperature dataset (Torok et al., 1996; Della-Martin et al.,
2004). Dark lines represent the mean of six models; shading represents the 6-model range
(derived from Grose et al., 2010 and White et al., 2010).
Figure 8. Projected changes in mean temperature to 2100 (high emission scenario). Projected
change in mean temperature for the IPCC high emission scenario (A2) between the periods
1988-1999 and 2090-2099, representing the projected change over the 21st century. The plots
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represent the mean of the 6-model projections calculated on an annual basis and for each
calendar season (derived from Grose et al., 2010).
3.3.2 Precipitation
The projection of total annual precipitation over the whole of Tasmania under either
emissions scenario shows no significant change. However, there are significant changes in
the spatial pattern of precipitation, and in the timing of precipitation. Under the high IPCC
emission scenario (A2), the annual average precipitation shows a steadily emerging pattern
of increased precipitation over most of the coastal regions, and no change or reduced
precipitation over central Tasmania and in some areas of northwest Tasmania (Figure 9).
The changes in seasonal precipitation are much stronger than annual total precipitation. The
west coast of Tasmania shows a pattern of strong increase in precipitation in winter and a
strong decrease in summer precipitation. The central plateau district shows a steady decrease
in precipitation in every season, and a narrow strip down the east coast shows a steady
increase in autumn and summer precipitation throughout the 21st century.
Figure 9. Projected changes in precipitation to 2100 (high emission scenario). Projected
proportional (%) change in total precipitation for the IPCC high emission scenario (A2) between the
periods 1988-1999 and 2090-2099, representing the change over the 21st century. The plots
represent the mean of six model projections calculated on an annual basis and for each calendar
season (derived from Grose et al., 2010).
Preliminary results suggest that climate change will also significantly affect Tasmania through
changes to extreme precipitation events. Figure 10 shows projected increases in extreme
precipitation events (here represented by the average number of days per annum exceeding
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the baseline 99th percentile) and increases in the maximum number of consecutive dry days
(<1 mm) by the end of the 21st Century (2070-2099) across many parts of Tasmania. This
suggests a combined change where more heavy precipitation events are interspersed with
longer, dryer periods which may lead to increased growth in bushfire fuels. This projected
change is particularly apparent in the western regions of the state.
These projected changes to precipitation are caused by systematic changes to the large-scale
climate features within the model simulations. These changes in the climate include a change
to the dominant pressure patterns and winds over the region as well as a change to the sea
surface temperature in the surrounding seas. Changes to the dominant pressure patterns are
associated with a southerly movement and intensification of the subtropical ridge of high
pressure, especially in summer, and an increasing prevalence of the high phase of the
Southern Annular Mode, resulting in changes to the dominant westerlies winds reaching
Tasmania. These changes are likely to enhance the seasonality of west coast precipitation,
that is, drier in summer and autumn and wetter in winter and spring.
Figure 10. Projected changes in extreme precipitation (high emission scenario A2). Projected
proportional (%) change in annual count of days exceeding the 1961-1990 99th percentile
(left panel), and the maximum number of consecutive dry days (<1 mm) per annum (right
panel), for 2070-2099 relative to 1961-1990. The plots represent the mean of the six model
projections (derived from White et al., 2010).
3.3.3 Relative humidity
Annual average relative humidity under the A2 scenario is projected to increase over much of
Tasmania by 0.5% to 1.5%, except for the Central Highland region where a slight decrease is
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projected (Figure 11a and 11b). There is a different spatial pattern of change in summer
compared to winter (Figure 11d).
Figure 11. Projected changes in mean relative humidity, a) time series of 11-year moving average relative humidity
over the land surface of Tasmania in the six-model-mean and the range of models (highest and lowest); b) the
difference in mean relative humidity between the periods 1 (1978-2007) and 2 (2070-2099); c) mean annual cycle
of relative humidity in periods 1 and 2; d) as for b) but for the calendar seasons summer and winter (derived from
Grose et al., 2010).
3.3.4 Wind speed
Change to the average 10-metre wind speed over the land surface of Tasmania under the A2
scenario shows a slight decline (<5%) by the end of the century (Figure 12a). The six-model-
mean pattern of change is spatially varied and there are large differences between the spatial
patterns of change in the six models (Figure 12c and 12d). A change in seasonality of mean
wind speed however is more apparent, with higher speeds in July to October and lower wind
speeds in November through to May (Figure 12b). Further in-depth analysis of wind speed,
wind gusts and wind hazards is included in the severe wind report as part of the Climate
Futures for Tasmania project (Cechet et al., 2010).
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Figure 12. Projected changes in mean 10-metre wind speed, a) 11-year moving average time series of annual 10
m wind speed over the land surface of Tasmania in the six-model-mean and the range of models (highest and
lowest); b) mean annual cycle for Tasmania in the periods 1 (1978-2007) and 2 (2070-2099); c) the six-model-
mean difference between periods 1 and 2; d), difference between periods 1 and 2 for each downscaled model
(same colour scale as for 6.16c) (derived from Grose et al., 2010).
3.3.5 Evaporation
The projected increase in temperature over the 21st century is the dominant driver of a
significant projected increase in potential evaporation across all four seasons. This is likely to
decrease water availability. Preliminary analyses indicate that evaporation will generally
increase across the state, although these increases are spatially varied. Because different
measures of evaporation can differ markedly, future researchers using the modelling outputs
and projections may need to derive their own measure of evaporation to best suit their
applications.
3.3.6 Soil moisture and water availability
The projected increases in CO2 concentrations may increase the water use efficiency of
vegetation and potentially reduce the demand on soil water reserves. This means that soil
water contents may conversely remain higher for longer into periods of low precipitation than
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might be expected as temperatures and evaporation increase. The impact of these changes is
as yet not quantified but may actually act to ameliorate bush fire danger ratings in some
regions. Biophysical models could be used to provide future projections of soil water contents.
3.3.7 Synoptic bushfire weather patterns
Particular synoptic weather patterns drive conditions of high fire danger. Mills (2005)
identifies a specific pattern that has been present in a large proportion of extreme fire events
in Tasmania, including the 1983 Ash Wednesday fires. This pattern is a particularly strong
and deep cold front that creates unusually hot and strong winds from the mainland of
Australia over the state.
This pattern can be identified by high temperatures and a strong thermal gradient at the 850
hPa height. This pattern can be identified and characterized in NCEP Reanalysis and in fine
scale climate model simulations. A preliminary examination of the Climate Futures for
Tasmania downscaled model projections reveals that they simulate the incidence of this
synoptic type reasonably closely to NCEP Reanalysis for the recent period. The model
simulations also project an increase of the incidence of this driver over the 21st Century
(Figure 13), with a large range indicated by the six different models examined. The model
mean is considered the best estimate for examining this change, and shows a 17% increase
by the middle of the century, and a 50% increase in incidence by the end of the century for a
high emission scenario (A2) of climate change.
Figure 13. Model mean number of extreme fire weather events in three periods (past period
and two future) modelled from six GCMs downscaled through CCAM (preliminary results).
Grey lined signifies range of the models for each period.
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3.4 Research directions
Fire danger is sensitively dependent on a number of related parameters. The projections
developed in the Climate Futures for Tasmania modelling hint at changes in the mean values
of these parameters that will impact on fire danger. In addition, the modelling has suggested
an increase in the frequency of synoptic patterns conducive to dangerous fire weather events.
The results to date indicate a need for further research, to more clearly identify trends in fire
danger and the broader area of bushfire risk. A project proposal has been developed to
extend the work of the Climate Futures for Tasmania team with a goal of examining in detail
projections of factors likely to impact on the occurrence of bushfires. Indices of fire danger
will be examined, as will changes in the frequency of synoptic weather conditions conducive
to the spread of bushfires. Other factors likely to affect bushfire activity and risk of ignition
will also be studied, including frequency of lightning risk levels and projections of change in
fuel load across the Tasmanian landscape.
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4 References
Alexander, L.V., Hope, P., Collins, D., Trewin, B., Lynch, A. and Nicholls, N. 2007. Trends in Australia’s climate
means and extremes: a global context. Aust. Met. Mag., 56, 1-18.
Bennett JC, Ling FLN, Graham B, Corney SP, Holz GK, Grose MR, White CJ, Gaynor SM & Bindoff NL, 2010, Climate
Futures for Tasmania: water and catchments, Antarctic Climate and Ecosystems Cooperative Research
Centre, Hobart (in press, due October 2010).
Brotak, E.A. and Reifsnyder,W.E. 1977. An investigation of the synoptic situations associated with major wildland
fires. Jnl appl. Met., 16, 867-70.
Cechet RP, White CJ, Bennett JC, Corney SP, Holz GK, Grose MR, Gaynor SM & Bindoff NL, 2010, Climate Futures for
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