Australia’s climate in a Four Degree World - Four Degrees of Global Warming - page 6

18

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16

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15

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1900 1950 2000

YEAR

2050 2100

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2050 2100

Figure 2.3 Central Victorian temperature (a) and rainfall (b), observed (solid) and
model-based projections

Notes
a Shown are the multi-model median (long dashed line) and the inner envelope (short
dashes) giving the spread of model projections based on the CSIRO&BoM (2007)
projections for a mid emissions scenario.
b The outer envelope allows for decadal scale variability.
c Method of constructing these is described in Watterson and Whetton (2011).

in the frequency of low-temperature extremes. Daily extremes will be considered
in detail in Chapter 3 , but here we consider the change in occurrence of cool
months and hot months (defined by a 1-in-20 year frequency in the historical
period) in south-eastern Australia 3 in a simulation which reaches 1 4°C global
warming by 2100 (see Figure 2.4 ). Cool months are very rare after 2040, and hot
months occur most of the time after 2070.