Western Adelaide Region Climate Change Adaptation Plan - Stage 1 - page 43

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Figure 4.14: Actual and the projected range in mean maximum and minimum temperature for each month at
Adelaide airport meteorological station.1
Source: Derived from Bureau of Meteorology data, using climate change factors from DENR 2010.
Note: The projected values used are from the 90th percentile outputs of GCMs under a high emissions scenario. Projected change
in temperature under less extreme modelling outputs, lower emissions scenarios and 2050 sit between the projected 2030 and
2070 values.
4.7.4.3. Heatwaves
Heatwaves have the capacity to affect physical infrastructure and the services they provide, as well as the
health and well-being of community members. Implications of heatwaves on human health are outlined in
Sections 6.17 and 15.2. Their impact depends on how often they occur, their duration and intensity (i.e.
how hot it gets), as well as the exposure and sensitivity of people and infrastructure to such conditions.
There is no definitive measure of a heatwave, but they are typically described as a prolonged period of
‘excessive heat’. Although this is dependent on factors including humidity and direct sunlight, many
studies consider heatwaves as consecutive days of over 35 or 40°C 3. In South Australia, the trigger point
for Extreme Heat Plans (to manage risks to vulnerable members of the community) is triggered by three
or more consecutive days where the average of daily maximum and minimum temperatures is greater
than 32°C. 4
Figure 4.15 shows the incidence of various forms of heatwave events for the Study Area, based on
Adelaide Airport. Over the climate change reference period (1980-1999), there were an average of 13.4
and 1.8 days per year with maximum temperatures of 35°C and 40°C or more, respectively. There was an
1 Projections for 2050 scenarios and less extreme 2070 scenarios lie between the two scenarios plotted.
3 http://www.bom.gov.au/wa/sevwx/perth/heatwaves.shtml,Accessed September 2012.
4 (http://www.ses.sa.gov.au/site/community_safety/heatwave_information/extreme_heat_plan.jsp; accessed February 2013
0
5
10
15
20
25
30
35
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Projected and actual mean monthly temperature (degrees)
Meanmax
monthlytemp
(1980-1999)
Meanmin
monthlytemp
(1980-1999)
2030Mean max
monthlytemp
2030Mean min
monthlytemp
2070Mean max
monthlytemp
2070Mean min
monthly temp