Friday, January 11, 2019

2018 third hottest on record for Australia with protracted drought, persistent heat


Australia's average temperature in 2018 was 1.14 °C above the 1961–1990 average, making it slightly warmer than 2017 said the Bureau of Meteorology in the 2018 Annual climate statement.

"When we look across all of Australia in 2018, we can see that every single state and territory had above-average day and night-time temperatures," Dr Bettio said.

"The average maximum temperature for the country as a whole was particularly warm, sitting 1.55 °C above the 1961–1990 average, making 2018 Australia's second warmest year on record for daily high temperatures.

"Average minimum temperatures for 2018 were 0.73 °C above average, the eleventh-warmest on record.

"The only part of the country to buck the trend for above average temperatures was the Kimberley region, which had cooler than average nights for the year."

On temperatures 2018 was Australia's third-warmest year on record; a year of protracted drought and persistent warmth.

Meanwhile, Australia still has no effective climate or energy policy, no consistent plan to phase out coal or gas fossil fuels, no plan to reduce transport emissions, a problem with increased vegetation clearing in Queensland and New South Wales. Australia's emissions are rising over the last 4 years and Environment department Data shows that Australia is unlikely to meet it's low 26 percent emissions reduction target by 2030.


See also: Mapping the heat trend in Australia's capital cities for 2018 and future projections

Annual mean temperatures for 2018 were above average for nearly all of Australia, and very much above average for most of the mainland except parts of Western Australia, mostly in the north and west, and parts of eastern Queensland. It was amongst the six warmest years on record for all States and the Northern Territory, and the warmest on record for New South Wales.

All capital cities except Melbourne and Perth ranked amongst the eight warmest years on record for annual mean temperature. Hobart had a particularly warm year, with annual mean temperatures the second-warmest on record.

Days were exceptionally warm for Canberra (annual mean maxima warmest on record) and Darwin (second-warmest on record), and also warm for Brisbane (fourth-warmest on record) and Sydney (fifth-warmest on record). Nights were warmer than average for each of those cities, but not especially so. Both days and nights were much warmer than average for Adelaide (maxima eighth-warmest on record, minima eleventh-warmest on record), and warmer than average for Melbourne, although outside the top ten. In Perth days were warmer than average.





Maximum temperatures - areal average



Rank ranges from 1 (lowest) to 109 (highest). A rank marked with '=' indicates the value is tied for that rank. Anomaly is the departure from the long-term (1961–1990) average.
Maximum Temperature
Rank
(of 109)
Anomaly

(°C)
Comment
Australia 108 +1.55 2nd highest (record +1.59 °C in 2013)
Queensland 106 +1.58 4th highest (record +1.78 °C in 2017)
New South Wales 109 +2.13 highest (was +1.92 °C in 2017)
Victoria 109 +1.44 highest (was +1.43 °C in 2014)
Tasmania 104 +0.77 6th highest
South Australia 108 +1.79 2nd highest (record +2.02 °C in 2013)
Western Australia 106 +1.27 4th highest (record +1.36 °C in 2014)
Northern Territory 108 +1.56 2nd highest (record +1.70 °C in 2013)

Minimum Temperatures - areal average



Rank ranges from 1 (lowest) to 109 (highest). A rank marked with '=' indicates the value is tied for that rank. Anomaly is the departure from the long-term (1961–1990) average.
Minimum Temperature
Rank
(of 109)
Anomaly

(°C)
Comment
Australia 99 +0.73
Queensland 99 +1.11
New South Wales 106 +1.23 4th highest (record +1.40 °C in 2016)
Victoria 104 +0.83 6th highest
Tasmania = 106 +0.65 equal 3rd highest (record +1.05 °C in 2016)
South Australia 99 +0.70
Western Australia 92 +0.35
Northern Territory 95 +0.65

Mean Temperatures - areal average



Rank ranges from 1 (lowest) to 109 (highest). A rank marked with '=' indicates the value is tied for that rank. Anomaly is the departure from the long-term (1961–1990) average.
Mean Temperature
Rank
(of 109)
Anomaly

(°C)
Comment
Australia 107 +1.14 3rd highest (record +1.33 °C in 2013)
Queensland 105 +1.35 5th highest
New South Wales 109 +1.68 highest (was +1.50 °C in 2017 and 2014)
Victoria 107 +1.14 3rd highest (record +1.21 °C in 2007)
Tasmania 105 +0.71 5th highest
South Australia 106 +1.25 4th highest (record +1.64 °C in 2013)
Western Australia = 103 +0.81 equal 6th highest
Northern Territory 105 +1.11 5th highest

Rainfall


"Nationally-averaged rainfall for 2018 was 412.8 mm, 11% below the 1961–1990 average of 465.2 mm, making it Australia's 39th-driest year in a record spanning 1900 to the present."

"Rainfall for the year was very low over the southeastern quarter of the mainland (seventh-lowest on record), with much of the region experiencing totals in the lowest 10% of historical observations. Annual rainfall was above average between the northwest coast of Western Australia and the southeast of that State. Rainfall was particularly low over the mainland southeast from April, with rainfall deficiencies increasing during the year for many areas. September was record-dry, but the final three months of 2018 were wetter in some areas."



Rainfall - areal averages
Rank
(of 119)
Average
(mm)
Departure
from mean
Comment
Australia 39 412.8 −11%
Queensland 37 527.4 −15%
New South Wales 6 332.0 −40% 6th lowest; lowest since 2002
Victoria 12 491.8 −26%
Tasmania 57 1389.4 0%
South Australia 32 171.3 −24%
Western Australia 82 375.7 +10%
Northern Territory 60 503.6 −7%
Murray-Darling Basin 7 289.5 −41% 7th lowest; lowest since 2006

Rank ranges from 1 (lowest) to 119 (highest). A rank marked with '=' indicates the value is tied for that rank. Departure from mean is relative to the long-term (1961–1990) average.

Sea Surface temperatures


The seas around Australia are also showing a consistent warming trend, with sea surface temperatures averaging for the year at tenth warmest on record. The year started with record warmth recorded in a huge area of the Tasmin Sea.


"The preliminary annual 2018 sea surface temperature (SST) anomaly for the Australian region was the tenth-highest on record; 0.46 °C above the 1961–1990 average based on data for January to November from the NOAA Extended Reconstructed Sea Surface Temperature dataset, ERSST v5. SSTs around Australia have warmed by around one degree since 1910, similar to the increase in temperature observed over land. Above average annual SSTs have been observed for the Australian region for every year between 1995 and the present, and have been persistently high for the past decade."

"Preliminary annual average SSTs were very much warmer than average across the eastern half of the Australian region. SSTs were warmest on record for some parts of the Tasman Sea, and for the Tasman Sea region as a whole, mean SSTs were the second-warmest on record (+0.86 °C for January–November 2018, behind +0.96 °C in 2016). For the Coral Sea, SSTs were the fourth-warmest on record (+0.61 °C)."


Climate change driving increased heat and drying trend in the south-west, and south-east Australia


The report makes clear that global warming and climate change is driving the long term increase in temperatures trend, and the changes to rainfall with the South west and south east of Australia becoming substantially drier.

Australia's climate is increasingly influenced by global warming. Australia has warmed by just over one degree since 1910, with most of the warming occurring since 1950. The ocean waters around Australia have also warmed significantly over the past century, and have been very warm to record warm consistently across the past two decades. The background warming trend can only be explained by human influence on the global climate. The role of climate change is further discussed in State of the Climate 2018.

There has been a significant decline in autumn and winter rainfall observed over southeast and southwest Australia in recent decades. The drying trend is particularly strong for May–July over southwest Western Australia since 1970, and for April–October over the southeast of the continent since 1999.
A major influence on this drying has been the strengthening and extension of the subtropical high pressure ridge during winter, shifting many potential rain-bearing weather systems south of the Australian continent. This southwards shift of frontal systems is an expected outcome of climate change.

Conversely, there has been an observed increase in rainfall over parts of northern Australia since the 1970s. This trend towards wetter years in the north is contributing to a slight increase in mean annual rainfall for Australia as a whole.

The impacts we are seeing now in increased temperatures and persistence of heat were highlighted as a trend back in 2004 by CSIRO and BOM: CSIRO warns: Australia to get hotter, wetter, with more extreme weather. Or read this 2010 article on Scientists affirm Australia's climate already changing. Succeeding state and Federal Governments have failed to sufficiently tackle the issue of climate and energy policy.

We are now facing a global crisis, a climate emergency due to the political in-action and intransigence.

We are now suffering escalating biodiversity crises with species reduction in numbers and threatened with extinction through the impact of extreme weather and our mismanagement of water, climate and energy policy.

The Spectacled flying fox suffered a one third loss to species numbers in the North Queensland heatwave. Koalas are also on the decline in Queensland and NSW through development as well as increasing heat and bushfires driven by climate change.

We have now lost 50-100 year old Murray Cod in the algal bloom and extreme heat along the Darling River and Menindee Lakes, estimated to have killed up to a million fish. While increasing temperatures and reduced stream flow in the Murray Darling Basin with 2018 rainfall 41 per cent below the mean and 7th lowest on record, it is the historical over-allocation of water from the river, and current poor management of water resources, the corruption and failure to prosecute water theft, that must be considered as a primary cause of the mass fish deaths.