The Great Australian Drought a one in one thousand year event
Select an article.
1: Australian major droughts
2: The Quaternary period and a 1000 year event.
3: Our diminishing water resources
4: Melbourne dust storm, 8 February 1983
5: Drought in Australia a natural phenomenon. 1791 - 2009
|Australian major droughts|
|1864-66||All States affected except Tasmania.||1963-68||Widespread drought. Also longest drought in arid central Australia: 1958-67. The last two years saw a 40 per cent drop in wheat harvest, a loss of 20 million sheep, and a decrease in farm income of $300-500 million|
|1880-86||Southern and eastern States affected.|
|1895-1903||Sheep numbers halved and more than 40 per cent loss of cattle. Most devastating drought in terms of stock losses.|
|1911-16||Loss of 19 million sheep and 2 million cattle.||1972-73||Mainly in eastern Australia.|
|1918-20||Only parts of Western Australia free from drought.||1982-83||Total loss estimated in excess of $3000 million. Most intense drought in terms of vast areas affected.|
|1939-45||Loss of nearly 30 million sheep between 1942 and 1945.||1991-95||Average production by rural industries fell about 10 per cent, resulting in possible $5 billion cost to the Australian economy,|
For a comprehensive list of Australian Droughts 1791 to 2009
Click here: Drought in Australia a natural phenomenon.
2007 Is the first time in Australian history, since weather records were kept, that the entire state of Victoria is affected by drought. Ground water bores , rivers and creeks are running dry throughout the district.
" An obvious example is the evidence that has come from Quaternary studies to show that we are in an unprecedented period of climate change.
Using sediment, coral and tree-ring records, it has been shown that temperatures in the last thousand years were relatively stable until 100 to 50 years ago.
In the last century, however, they have soared well beyond those of the previous 1000 years, suggesting, as Haberle puts it, 'that we are in a period of very unusual climate change and ... that the most likely explanation is that this is a human-driven climate period.' "
The Quaternary covers the last two million years of history which, as it happens, coincides with human history. 'So it's the evolution of Homo sapiens and all the things that go on around that,' Haberle explains. It brings together a range of disciplines that are interested in that particular period, including geologists, archaeologists and anthropologists. "
Dr Simon Haberle talks to Gia Metherell about the interdisciplinary nature of the Quaternary research community.
Irrigation ban in the Murray-Darling river basin. 2007
The Murray-Darling river basin has been called Australia's "food bowl".
It generates about 40 per cent of the country's farm produce.
If this tract of land - the size of France and Spain combined - is denied irrigation it would spell ruin for Australia's agricultural sector.
Thousands of farmers could lose their citrus, apple, pear, peach, apricot, almond and olive trees if they cannot be watered.
Trees would die and production would be impossible for at least half a decade. Even if the rains do come in Australia in the coming weeks, as forecast, they will have to be especially long and prolonged to alleviate the crisis.
Throughout the state cattle, sheep and the dairy industry are also suffering.
The most irrigated land in Australia is located within the confines of the Murray-Darling Basin, which covers parts of New South Wales, Victoria, Queensland and South Australia.
The Murray-Darling Basin is of particular significance as a catchment.
It contains Australia’s three longest rivers, the Darling (2,740km), the Murray (2,530km) and the Murrumbidgee (1,690km).
The development of irrigation in the Murray-Darling Basin was supported by public investment in infrastructure that began in the early 1900s, with the double objective of increasing agricultural exports and moving people back to rural Australia.
Living in the world’s driest inhabited continent, Australians are used to a multitude of wild schemes promising deliverance from drought and
the much needed precious water.
But with Government officials saying last month that the drought gripping Australia could be the worst in 1000 years, emergency plans are being drawn up to secure long-term water supplies to towns and cities.
Previously it was thought that the drought effecting more than half the country’s farmlands was the worst in just 100 years, and with rivers disappearing and a searing spring, desperate farmers are being asked to pack up and open a ‘new agricultural frontier’ in the tropical north.
Source: REUTERS/David Gray (Australia)
August 2007 The Australian Government has offered farmers a $150,000 cash incentive to farmers to pack up and leave their drought stricken farms.
Our diminishing water resources
The 1982-83 Drought. Short and intense. ( C )
In terms of short-term rainfall deficiencies (up to one year) and their overall impact, the 1982-83 drought was perhaps the worst in Australia this century.
In autumn 1982 reasonable rains were fairly widespread, except for southern Western Australia, which had an exceptionally dry autumn. With the coming of winter, however, intense drought became established in most areas east of a line from Alice Springs to Ceduna. There were frequent sharp frosts in June and July, accompanying clear skies and low atmospheric moisture levels.
By the end of August the wheat crop in eastern Australia was on the verge of failure, and sheep prices plummeted as graziers reduced flocks. Very dry conditions persisted through spring over eastern Australia (except in coastal areas of northern New South Wales), with extensive areas experiencing record or near-record low rainfall totals from April to December.
By November, dry soil in north western Victoria was blown away as dust; water restrictions were imposed in Melbourne; and on 24 November the earliest Total Fire Ban in 40 years was proclaimed in
The upper Murrumbidgee River became a chain of waterholes: by year’s end reservoirs fell to levels not known for many years.
The remains of Tallangatta and Bonnie Doon, Victorian towns relocated in the 1950s to allow enlargement of Lake Hume and Lake Eildon, emerged from the shrinking waters.
The summer Wet season failed in the Northern Territory and north Queensland, with record low summer rainfall in some areas. What little rain there was often fell on bare earth and without follow-up, and was therefore of little use.
Only northeastern NSW and southeastern Queensland truly escaped the drought. The nadir was reached in February 1983, with record low rainfall in parts of Tasmania, and virtually none at all in Victoria.
Fires flared in southeastern Tasmania on the 1st and 8th, spectacular dust-storms swept Victoria on the 8th, and the Ash Wednesday fires devastated Victoria and South Australia on the 16th.
In Melbourne, on the 8 February 1983 the temperature rose quickly as the north wind strengthened, and by 2:35pm it had reached 43.2°C, a record February maximum.
A short time later, a spectacular reddish-brown cloud could be seen advancing on the city, reaching Melbourne just before 3pm.
It was accompanied by a rapid temperature drop, and a squally wind change strong enough to uproot trees and unroof about 50 houses.
Visibility plunged to 100 metres, and according to witnesses “everything went black” as the storm struck.
The worst of the dust-storm was over by 4pm, when the wind-speed dropped rapidly.
eastern Victoria, fires burned unchecked for most of the month.
Relief came at last in March: ironically, the first rains arrived inopportunely at grape harvest time in South Australia and Victoria.
An intense low pressure system then developed over northwestern Australia on the 12th, and over the next week drifted eastward with heavy rain and flooding.
It then tracked south over NSW and Victoria, to Tasmania by the 23rd.
Substantial rain fell over almost all the drought area, with many record March totals. Abundant follow-up rains in April and May signified the end of the drought.
Total losses attributed to this drought exceeded $3 billion. Its association with the very strong El Niño event of 1982-83 marked the transformation of El Niño from abstract climate phenomenon to common lexicon, and set the scene for many of today’s climate forecasting techniques.
The dust storm of 23 October 2002
The dust storm of 23 October 2002 covered most of eastern Australia and carried one of the largest recorded dust loads in Australia.
In the 6 months leading up to the event, severe drought conditions in eastern Australia, plus above average maximum temperatures resulted in high potential evapo-transpiration rates, producing severe soil moisture deficits and reduced vegetation cover.
Although increased wind speeds associated with a fast moving cold front were the meteorological driving force, these winds speeds were lower than those for the previously documented large dust storms.
The dust storm was 2400 km long, up to 400 km across and 1.5–2.5 km in height.
The plume area was estimated at 840,860 km2 and the dust load at 0900 h was 3.35–4.85 million tones (Mt).
These dust load estimates are highly sensitive to assumptions, regarding visibility–dust concentration relationships, vertical dust concentration profiles and dust ceilings.
The decline of the annual rainfall totals for Romsey ( Australia ).
The 32 year rainfall records from 1975 onwards show a marked and steady decline in precipitation since 1994.
There was a an average decline of 150 mm or 6 inches over the period from 1994 to 2006.
|Is there a risk of a Volcanic Eruption in Australia?|
|Australian Food Additives Codes|
|Lethal Australian Ants|
|Food Poisoning in Australia.|