Drought in Australia

A dried up Lake Hume, 2007

Drought-affected fields in the Victorian countryside, 2006

Drought in Australia is defined by the Australian Bureau of Meteorology as rainfall over a three-month period being in the lowest decile of what has been recorded for that region in the past.^[1] This definition takes into account that drought is a relative term and rainfall deficiencies need to be compared to typical rainfall patterns including seasonal variations. Specifically drought in Australia is defined in relation to a rainfall deficiency of pastoral leases and is determined by decile analysis applied to a certain area.^[2] Note that this definition uses rainfall only because long-term records are widely available across most of Australia. However, it does not take into account other variables that might be important for establishing surface water balance, such as evaporation and condensation.

Historical climatic records are now sufficiently reliable to profile climate variability taking into account expectations for regions.^[3] Bureau of Meteorology records since the 1860s show that a ‘severe’ drought has occurred in Australia, on average, once every 18 years.^[4] State Governments are responsible for declaring a region drought affected and the declaration will take into account factors other than rainfall.^[1]

The worst drought to affect the country occurred in the 21st century—between the years 2003 to 2012. Nonetheless, many regions of Australia are still in significant drought and rainfall records have showed a marked decrease in precipitation levels since 1994, with many scientists attributing this to climate change and global warming.^[5] Deficiencies in northern Australia increased in 2013–14, leading to an extended drought period in certain parts of Queensland.

Droughts in the 19th century

• 1803 Drought in New South Wales (NSW) that produced severe crop failures.
• 1809 Beginning of an unusually severe drought in NSW that continued until 1811.
• 1813−15 Severe drought in NSW that prompted searches for new pastures.
• 1826−29 Severe drought in NSW that caused Lake George to dry up and the Darling River to cease flowing.^[6]

Since 1860, when adequate meteorological recording commenced, the most severe droughts have occurred commonly at intervals of 11 to 14 years. Major droughts that were recorded later in the 19th century include:

• 1829 Major drought in Western Australia with very little water available.^[7]

• 1835 and 1838 Sydney and NSW receive 25% less rain than usual. Severe drought in Northam and York areas of Western Australia.
• 1838−39 Droughts in South Australia and Western Australia
• 1839 Severe drought in the west and north of Spencer Gulf, South Australia.
• 1846 Severe drought converted the interior and far north of South Australia into an arid desert.
• 1849 Sydney received about 27 inches less rain than normal.
• 1850 Severe drought, with big losses of livestock across inland New South Wales and around the western rivers region.
• 1864−66 (and 1868). The little data available indicates that this drought period was rather severe in Victoria, South Australia, New South Wales, Queensland and Western Australia.
• 1877 All states affected by severe drought, with disastrous losses in Queensland. In Western Australia many native trees died, swamps dried up and crops failed.
• 1880 to 1886 Drought in Victoria (northern areas and Gippsland); New South Wales (mainly northern wheat belt, Northern Tablelands and south coast); Queensland (1881–86, in south-east with breaks – otherwise mainly in coastal areas, the central highlands and central interior in 1883–86); and South Australia (1884–86, mainly in agricultural areas).
• 1888 Extremely dry in Victoria (northern areas and Gippsland); Tasmania (1887–89 in the south); New South Wales had the driest year since records began; Queensland (1888–89) had a very severe drought, with much native scrub dying and native animals perishing; South Australia had one of its most severe droughts; and Western Australia (central agricultural areas) lost many sheep.^[8]
• 1897 Drought in much of Queensland, compared to 1883–84 droughts.^[9]

Drought in the 20th century

Federation drought

A dried-up lagoon in Wagga Wagga, New South Wales during the 1912 drought.

At the time of Federation, Australia suffered a major drought. There had been a number of years of below average rainfall across most of Australia before the drought. During the drought the wheat crop was "all but lost"; and the Darling River was dry at Bourke, New South Wales, for over a year, from April 1902 to May 1903. There was concern about Sydney's water supply.^[10] By 1902 Australia's sheep population dropped from its 1891 level of 106 million to fewer than 54 million. Cattle numbers fell by more than 40 per cent. Sheep numbers did not return to 100 million until 1925.

In the 1911–1915 period, Australia suffered a major drought, which resulted in the failure of the 1914 wheat crop.^[11] During 1918 to 1920, a severe drought was experienced by Queensland, New South Wales, South Australia, Northern Territory (Darwin-Daly Waters area and central Australia), Western Australia (Fortescue area), Victoria, and Tasmania.

Other 20th century droughts

1937-1947 drought

During World War II, eastern Australia suffered dry conditions which lasted from 1937 through to 1947 with little respite.^[12] The end of the drought coincided with the 1946-47 Ashes series, it rained in all 25 matches played by the tourists, including two tropical rainstorms during the First Test at Brisbane and another in the Second Test at Sydney.^[13]

1960s

From 1965–68, eastern Australia was again greatly affected by drought. Conditions had been dry over the centre of the continent since 1957 but spread elsewhere during the summer of 1964/1965. This drought contributed to the 1967 Tasmanian fires in which 62 people died in one day and 1,400 homes were lost.^[14]

1980s

The drought in 1982–83 is regarded as the worst of the twentieth century for short-term rainfall deficiencies of up to one year and their over-all impact. There were severe dust storms in north-western Victoria and severe bushfires in south-east Australia in February 1983 with 75 people killed.^[15] This El Niño-related drought ended in March, when a monsoon depression became an extratropical low and swept across Australia's interior and on to the south-east in mid- to late March.

1990s Queensland drought

A very severe drought occurred in the second half of 1991^[16] which intensified in 1994 and 1995 to become the worst on record in Queensland.^[17] This drought was influenced by a strong El Niño weather pattern and associated with high temperatures in July and August 1995, the fifth continuous year of drought in parts of Queensland. According to Primary Industries Minister, Ed Casey, "the drought affected region stretched in a 200 km to 300 km wide strip from Stanthorpe to Charters Towers".^[18] So few wheat and barley crops survived, about half the usual for that year, that grains had to be imported from other states.^[19]

In June 1994, more than ten towns had lost irrigation systems; and some areas had gone five years without decent rainfall.^[18]

A part of the upper Darling River system collapsed during this drought. By October 1994, the Condamine River was exhausted, reverting to a series of ponds. Across the state more than 13,000 properties, totaling 40% of Queensland was drought declared.^[20] The flow past Goondiwindi was the lowest since 1940. Cotton farms near Moree and Narrabri had been allocated no water for irrigation, which resulted in a major loss of production.^[20] The town of Warwick was particularly affected.

Drought in the 21st century

2000s or 'Millennium' drought in south-eastern Australia

From 1996 to 2010 south-eastern Australia experienced prolonged dry conditions with rainfall persistently well below average, particularly during the cooler months from April to October. The most acute period of the so-called 'Millennium drought' was between 2001 and 2009. The drought finished with the arrival of wet La Niña conditions during 2010 and 2011, with particularly heavy summer rainfall.^[21]

Green drought, caused by insufficient rain after a long dry period, November 2002

1996 to 2000: patchy rainfall in the south-east

Dry conditions began to emerge in south-eastern Australia during late 1996 and accentuated during the strong 1997 El Niño event.^[22] Rainfall in 1998, 1999 and 2000 was closer to average, with isolated areas affected by rainfall well below average.

2001 to 2009: the peak of the drought

According to the Bureau of Meteorology, much of eastern Australia experienced a dry 2001.^[23] 2002 was one of Australia's driest and warmest years on record, with 'remarkably widespread' dry conditions, particularly in the eastern half of the country which was again affected by El Niño conditions. It was, at the time, Australia's fourth driest year since 1900.^[24]

The El Niño weather pattern broke down during 2003 but occasional strong rainfall in 2003 and 2004 failed to alleviate the cumulative effect of persistently low rainfall in south-eastern Australia, with some measurement stations having recorded below average rainfall for eight consecutive years.^[25] Rainfall in early 2005 remained below average, and better rainfall in the second half of the year again failed to break continuing drought conditions in the south-east.^[26]

Dry paddocks in the Riverina region during the 2007 drought

South-east Australia experienced its second driest year on record in 2006, particularly affecting the major agricultural region of the Murray-Darling Basin.^[27] 2007 saw record temperatures across the south of Australia, and only patchy rain; promising early year rains contrasted with a very dry July-October period, meaning that drought conditions persisted across much of the south-east. At this point, the Bureau of Meteorology estimated that south-eastern Australia had missed the equivalent of a full year's rain in the previous 11 years.^[28]

2008 and 2009 saw continuing hot and dry conditions in south-eastern Australia, with occasional heavy rainfall failing to break the continuing drought. The effects of the drought were exacerbated by Australia's (then) second hottest year on record in 2009, with record-breaking heatwaves in January, February and the second half of the year.^[29]

2010 and 2011: La Niña finally breaks the drought

Australia's weather pattern transitioned rapidly to a wet La Niña pattern during autumn, resulting in record-breaking rains in the Murray-Darling Basin and well above average rainfall across the south-east. For many locations this was the first year of above-average rainfall since 1996. The rainfall dramatically increased surface water storage and soil moisture, effectively ending the drought in the south-east.^[30] Very wet conditions continued through 2011, resulting in floods in Queensland and northern Victoria.^[31]

Effects on agricultural production

Dairy producers were hit particularly hard by the drought. 2004 was a particularly bleak year in the sector with revenue in the industry falling by 5.6%.^[32]

Cattle on a sand island in the Murrumbidgee River which is normally underwater but due to low rainfall in the catchment during 2008 meant water releases from the dams were reduced.

Agricultural production has been affected. Water use by the industry fell by 37% between 2000/01 and 2004/05, due mainly to drought.^[33] In the order of 20 cotton communities and 10,000 people directly employed by the cotton industry are impacted by the drought. The main areas affected are in New South Wales: Menindee where the area under production has reduced by 100%, Bourke has reduced the area under production by 99%, Walgett has reduced the area under production by 95%, the Macquarie River has reduced the area under production by 74% and the Gwydir River has reduced the area under production by 60%. In Queensland the worse affected areas are Biloela which has reduced the area under production by 100%, at Dirranbandi there has been a 91% reduction, Central Highlands has reduced the area under production by 82% and Darling Downs has reduced the area under production by 78%. Bourke has only had adequate water for one cotton crop in the last five years.^[34]

Stock feed is also becoming scarce and farmers are finding it difficult to feed cattle and sheep.

2013–2015

Dry conditions again began to develop and be sustained in mid-2013 through much of western Queensland.^[35] Although these began easing for western Queensland in early 2014, drought began to develop further east, along the coastal fringe and into the ranges of southeast Queensland and northeast New South Wales.^[36]

Dry conditions continued into 2015 in the east, particularly in Queensland where the monsoon rains were delayed. Queensland had experienced poor wet season rains for three consecutive seasons.^[37] Wetter conditions in 2016 eased the effects of drought in eastern Australia, but pockets of south-east Queensland and north-east New South Wales remained drier than average.^[38]

See also

• Climate change in Australia
• Deserts of Australia
• Extreme weather
• Federation Drought
• List of reservoirs and dams in Australia
• Peak water
• Send her down Hughie
• Water restrictions in Australia

References

External links

Wikimedia Commons has media related to Drought in Australia.

• Drought
• Drought in Australia on Australian Bureau of Statistics
• Drought in Australia on Bureau of Meteorology