Deliquin on the weather map
This is the fourth in a series of monthly columns written by Alan Henderson on historical events and issues in the District of Deniliquin. Alan’s grandfather bought ‘Warragoon’ on Finley Road in 1912. Alan was born in Deniliquin Hospital in 1944 but moved to Canberra in 1967. In retirement he wrote a family history, Boots, Gold and Wooland will share some of his research in this local history column.
Deniliquin was one of 33 locations in a chart alongside the first weather map published in an Australian newspaper – the Sydney Morning Herald — February 5, 1877.
Many of the early weather stations have closed, so Deniliquin now holds a distinct status among the hundreds of stations that continue to be registered on the Bureau of Meteorology website.
At over 160 years old, Deniliquin is the oldest station reporting daily rainfall data, and the fourth oldest among stations reporting monthly.
The long series of data for Deniliquin makes it possible to assess, for example, the increased frequency of days of extreme heat, but also to identify the most severe droughts since the arrival of European settlers.
I remember mentioning global warming to my older sister, Noelle Browne, and she said, “Oh, Al, there were a lot of hot days when I was young.”
It’s possible that 1930 was etched in his year-old brain, as there were 42 days that exceeded 35°C that year.
I calculated the average number of “hot days” above two thresholds – 35°C and 40°C – for two 10-year periods: 1929-1938, the first decade of Noelle’s life, and 2011- 2020.
In the 10 years to 1939, the annual average number of days above 35°C was 25, and in the 10 years to 2020 it was 38 days.
In the 10 years to 1939, the average annual number of days above 40°C was 3.5, and in the 10 years to 2020 it was 9.2 days.
The most extreme year was 2019 — the temperature exceeded 35°C for 57 days and exceeded 40°C for 22 days.
The most widespread and severe Australian droughts since European settlement have been the Federation Drought (1895-1903), World War II Drought (1939-45) and Millennium Drought (1997-2009), the latter being the most serious.
In the eight years between 1895 and 1902 of the Federation Drought, rainfall in Deniliquin averaged 320 mm compared to the long-term (1858-2020) average of 407 mm.
The national number of sheep, which had reached more than 100 million, was reduced by about half and the number of cattle by more than 40%.
A significant number of stocks from the Deniliquin District were transported south to Gippsland or east to the New South Wales Highlands.
The Edward River has been reduced to a chain of ponds. On November 12, 1902, with a temperature of 37.5°C, a dust storm became so dense for about half an hour beginning at 6 p.m. that Deniliquin experienced “total darkness”.
The World War II drought was less severe and shorter.
In the five years from 1940 to 1945, precipitation averaged 339 mm. Additionally, it was possible to mitigate the impact of drought in some areas of the district because the Hume Weir was completed in 1936, Stevens Weir was completed in 1935, followed by the creation of the Wakool Irrigation District and, at the end of 1940, the Mulwala Canal was very close to Deniliquin.
My father was irrigating from the Mulwala Canal at Blighty in September 1940.
His journals indicate that within a few years the cattle were rotating through an oasis of alfalfa and other irrigated pastures.
In contrast, in 1938, a very dry year, the typical first task of the day changed from “walking around all the sheep” to “feeding all the sheep”, spending over $100,000 at current prices on untreated fodder. agricultural, including barley, Thorpes ewe nuts, Riverina nuts and mangels (large beets).
In Deniliquin, the millennial drought extended from 2001 to 2009, with average precipitation over these nine years of 320 mm.
In the six decades since the onset of the World War II drought, the ability of the irrigation system to mitigate the impact of drought on individual farmers had diminished.
Greater use of water rights combined with more water-intensive agriculture means that under severe drought conditions the allocations against water rights have decreased significantly.
Another thing that has changed since World War II, in this case for the better, is the accuracy of weather forecasts.
My father was a follower of Inigo Jones (1872-1954), the famous long term meteorologist.
Silence was demanded when his last statements were broadcast on the radio.
It would have distressed my father to read a biography of Jones’ professional life suggesting that he exhibited many characteristics of quackery.