Information response MCU13/0030

        Climate change impacts


A3.7    Climate change is expected to cause a gradual change in vegetation health and vigour, and
        some  species and vegetation communities will be advantaged over others. Climate change
        impacts will be reflected over time through changes to vegetation communities and fuel
        characteristics. These changes are difficult to predict and are likely to occur very
        gradually over a long timeframe. The changes to bushfire hazard associated with climate
        change impacts will generally be outweighed by changes caused by human activity in the
        short term. For these reasons it is not practicable to consider the impacts ofclimate
        change in bush:fire hazard assessment studies at present.

        Methodology for assessing bushfire hazard43

A3.8    The methodology involves quantitative and qualitative assessments. The quantitative
        element requires an assessment of three key characteristics of land that have been found to
        be the main determinants ofthe severity ofbushfire hazard. These factors are vegetation
        communities, slope and aspect.

A3.9    The area to be assessed should be disaggregated into sub-units according to vegetation
         communities, slope and aspect characteristics. Tables A3.1 to A3.3 provide the ranges
         that should be applied for the analysis of each ofthe three factors. These ranges will also
         help to determine the sub-units that should be used to conduct the assessment. The size of
         the sub-units, and level of accuracy of the resultant bushfue hazard map, may vary with
         the extent ofthe area being assessed, the characteristics of the land and vegetation
         communities, and the accuracy of the base information being used.

Aloi0 Each sub-unit is allocated a score for each fthe three factors. The total score for each
         sub-unit determines the severity of bushfue hazard for that sub-unit. A qualitative review
         of these findings should then be undertaken to verify the results of the quantitative
         assessment.


A3.U     The qualitative review should consider the known bushfrre behaviour.


A3.12 Finally, a safety buffer of land in close proximity to identified bushfue hazard areas needs
      to be included within the natural hazard management area (bushfire). The safety buffer is
         required because bushfires can affect unvegetated land in close proximity, particularly due
         to winds fanning flames, smoke,embers and radiant heat.


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          Step 1:Assessment-of vegetation-communities

 A3.13 The different types of vegetation communities determine the rate at which dry fuel
       accumulates. Some vegetation communities protect fuel from drying out in all but
          extreme bushfrre seasons and can then be susceptible to very destructive bushfires.

          Alternatively, vegetation communities may expose fuels to drying and therefore be
          frequently available for burning. Frequent bushfues can result in the development of
          bushfrre-tolerant grassy woodlands or grasslands and less destructive bushfire behaviour.
          The characteristics of different vegetation communities are reflected in Table A3.1. This



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       Alternative methodologies may also be acceptable but should be referred to the QFRS for assessment and
       approval prior to implementation.



 spp Guideline 1103                                                                                    June 2003
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