Hello all
Note the BOM rainfall map indicating 2010 was the wettest year on record for the area
where Princess Parrots irrupted.
see
http://www.bom.gov.au/announcements/media_releases/climate/change/20110105.shtml
However apart from local anomalies, the information appears to be not quite correct.
Despite the hype surrounding current outback seasonal conditions, 2010 was not the highest
outback rainfall event in recent history. In many areas of Central Australia 2010 was not
even close to the record event it has been portrayed to be. (See links below)
Why do so many of us often think we are experiencing the wettest/driest, hottest/coldest,
biggest/smallest weather events on record when a careful study of the daily records from
ALL the available stations show that in only 150 years of records we rarely are?
Sometimes even the Met Bureau misinterprets the available information. Is someone
pushing their climate change agenda a little hard? Is there is a selective process in
play or is someone careless with their research.
Mostly I blame the media and marketing hype from some desperate tourism operators who
sometimes guild the lily just a bit. The flooding of Lake Eyre is a classic example of
this. How often do we hear this is a once in a generation event. Not true.
Except during extended drought periods, Lake Eyre takes water from various tributaries
particularly The Neales, Macumba, KallaKoopah and Warburton about 3 times every decade.
The Cooper Creek however rarely flows into Lake Eyre. Although it reached the lake in
1989 and 2010, the last time it contributed any significant water to the lake level was
1971, 1974 – 76.
In 2010 although the Lake Eyre tributaries flooded and filled the Warburton Groove, water
barely reached the samphire margins with only a very shallow cover on the lake surface.
When the wind blows across the lake surface, water moves downwind giving an impression of
flooding but if the wind changes you can be looking at a dry area of lake within 24 hours.
By comparison, in 1974 the lake filled to a depth of nearly 10 metres. You can still see
the wave cut platforms grooved horizontally into the soft calcareous soils of the Halligan
Bay mesas.
Sometimes small area weather anomalies break local records and clearly the media enjoys
making great mileage from this. Such localised events are not comparable with great wet
events such as 1974 when from January rainfall amounts of more than 40 inches fell over a
3 month period across much of Central Australia north from Port Augusta to the Gulf of
Carpentaria, Top End and Kimberley. The whole lot flooded. Lake Eyre filled up backing
north into the Simpson Desert and then backed across the NT border. The desert sand dunes
became islands where water birds bred in numbers that defied description. This resulted
in the 1970's waterbird population explosion and partly helps explain why there has been a
decline of water bird numbers since official counts began in 1983.
In 1974 many outback stations around the Princess Parrot habitats received rainfall around
1000 mm and more. See Yuendumu, Newhaven, Erldunda etc. Alice Springs also enjoyed
exceptional conditions in those years too.
Interestingly Cyclone Tracy occurred in December 1974. This was a separate weather event
to the outback flooding that commenced in January although at the same time the remnants
of Cyclone Wanda flooded much of Brisbane.
See Yuendumu NT
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=015528
See Alice Springs NT
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0015590
See Newhaven NT
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0015611
See Ali Carung NT
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0015502
See Erldunda NT
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0015574
See Arkaroola SA
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0017099
See Blinman SA
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0017014
See Frome Downs SA
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0020006
See Innamincka SA
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=0020006
See Birdsville Qld
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=038002
See Winton Qld
http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_stn_num=037051
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