Geoscience Reference
In-Depth Information
By 2030, it is likely (greater than 66 per cent probability) that a 1-in-20-year
drought during the 20th Century will become a 1-in-10-year drought over south-
west Western Australia.
By 2050, this will include the Murray-Darling Basin, South Australia and
Victoria, and by 2070 this will extend to eastern New South Wales and
Tasmania. No significant increases in drought frequency are projected for north-
west Western Australia or northern and central Queensland.
Hail
Projections of change in hail risk for the end of the century (CSIRO and
BoM, 2007), based on the CSIRO Mark 3.5 model and a high (A2) emissions
scenario, show an increase along the south-eastern coastline by the year 2070
(
Figure 3.10
)
. The results also show a decrease in hail risk along the south coast
of Australia. However, since these results are based on only one climate model,
confidence in the patterns of change is low.
The University of Oklahoma climate model was run at 1km resolution over
the Sydney region to estimate changes in hail risk for 20012050 under a medium
_10
0
days 12
10
_20
0
8
6
_30
0
4
\
' ......,'... _ ..... _ .... _/i'-
-
-_ ...... -\
2
_40
0
~70
120
0
130
0
140
0
150
0
Figure 3.10
Projected changes for 2070 in risk of large hail
Source: Bureau of Meteorology (Australia)
Notes
a Risk = days per year
with
large hail.
b Large hail = hail of 2cm diameter.
c Shaded contours show increases in frequency, while dashed contours show decreases
in frequency.
d From the CSIRO Mk3.5 model for the A2 emission scenario.
