BAMOS
Mar 2019
Other key findings from the report:
• Australia’s climate has warmed by just over 1 °C since
1910, leading to an increase in the frequency of extreme
heat events (See Figure 1).
• April to October rainfall has decreased in the southwest
of Australia. Across the same region May–July rainfall has
seen the largest decrease, by around 20 per cent since
1970.
• There has been a decline of around 11 per cent in April–
October rainfall in the southeast of Australia since the late
1990s.
• Streamflow has decreased across southern Australia.
Streamflow has increased in northern Australia where
rainfall has increased.
• There has been a long-term increase in extreme fire
weather, and in the length of the fire season, across large
parts of Australia.
• Oceans around Australia have warmed by around 1 °C
since 1910, contributing to longer and more frequent
marine heatwaves.
• The last two years (2016 and 2017) have seen mass
bleaching over parts of the Great Barrier Reef in
consecutive years for the first time, with the northern
Reef experiencing bleaching in both summers.
• Sea levels are rising around Australia, increasing the risk
of inundation.
• The world’s oceans are taking up more than 90 per
cent of the extra energy stored by the planet as a result
of enhanced greenhouse gas concentrations, and the
southern hemisphere oceans have taken up the majority
of this heat (Figure 2).
• Australia is projected to experience:
» » Further increases in sea and air temperatures, with
more hot days and marine heatwaves, and fewer
cool extremes.
» » Further sea level rise and ocean acidification.
» » Decreases in rainfall across southern Australia with
more time in drought, but an increase in intense
heavy rainfall throughout Australia.
The Bureau of Meteorology and CSIRO play a key role in
monitoring, measuring, understanding and reporting on
weather and climate phenomena. State of the Climate draws
on the best available peer-reviewed information including
scientific observations based on multiple evidence sources.
Watch the State of the Climate 2018 video.
Read State of the Climate 2018.
Figure 2. Estimated change in ocean heat content over the full ocean depth, from 1960 to 2017. Shading provides an
indication of the confidence range of the estimate. Estimates of global ocean heat content have been enhanced in recent
years with the deployment of thousands of robotic submersible floats worldwide, as part of the international Argo
program. Note that data contributing to the early part of the record are sparse and trends estimated over this period are
small compared to the error bars, hence considered unreliable.
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