Unearthing Australia’s climate history

Dr Joelle Gergis, Professor David Karoly, Associate Professor Don Garden, Claire Fenby and Linden Ashcroft

School of Earth Sciences, The University of Melbourne

Image: Shutterstock

The ‘land of drought and flooding rains’: our unwritten history

Images: Fairfax Publishing

South Eastern Australian Recent Climate History (SEARCH) Project: Sept 2009–Aug 2012

- Multi-disciplinary Australian Research Council (ARC) Linkage Project

- Meteorologists, palaeoclimatologists hydrologists, historians, joined by a broad range of partner organisations

- Three research themes:

• Early weather records (pre Bureau of Meteorology)

• Historical documentary sources

• Palaeoclimatology

- Looking at extending southeastern Australia’s climate record and assessing how climate variability has influenced society since 1788

The 1997–2009 ‘Big Dry’ in south-eastern Australia

- Average surface temperatures over Australia have increased by 0.7°C since 1960, while mean temperatures have risen by ~1°C in SE Australia over the past 50 years

- Lowest 13-year rainfall period since instrumental records began in 1900, followed by very wet 2010-11.

- How does the 1997–2009 drought compare to events not recorded in 20th century weather records?

- Is SE Australia seeing the start of a similar drying trend found in SW Western Australia since 1970s?

Source: Australian Bureau of Meteorology

Record low inflows to Melbourne catchments

• During 1997-2011, Melbourne catchments received inflows 30% below long term averages, even including the heavy rain in 2010 and 2011

• How much is natural decadal variability and how much is due to human-influenced increases in temperature?

Source: Melbourne Water

Is the recent drying in SE Australia extreme climate variability or climate change?

“The further back you look, the further forward you can see” (Winston Churchill)

- Despite large climate variability and major climate impacts, we still don’t know how temperature and rainfall have fluctuated during pre-industrial times

- We can improve estimates of the range of natural climate variability by looking at pre-C20th records provided by palaeoclimate and historical sources

Dust storm Mildura, VIC 1940 Flood, Punt Rd, Melbourne 1891Source: Museum Victoria Source: Fairfax Publishers

Extending south-eastern Australia’s climate record back to 1788

AIM: To extend SE Australia climate record back to 1788 and investigate the influence of past climate variability on Australian societies:

1. Instrumental weather observations: Bureau of Meteorology holdings, weather/farm diaries, early observatories (1788–2012)

2. Documentary records: early settler accounts, newspapers, government records (1788–1900)

3. Palaeoclimate data: tree-rings, corals, cave records, ice cores (200–1000 years)

** First project of its kind funded in the Australasian region**

Bureau of Meteorology records

Image: Adapted from Bureau of Meteorology (BoM), 2000

1788–1910 SE Australian instrumental data

• Daily noon temperatures and pressure recorded in a ship log onboard the Sirius by William Bradley during the 8 month First Fleet voyage from England to Australia in 1787–1788

• Saw snow as they rounded Tasmania in January (summer!) 1788, very cold and wet, sails ripped in howling winds, convicts on their knees at prayers

• Some of the earliest meteorological observations from the Southern Hemisphere

Source: Gergis, Brohan and Allan, Weather 2010

First Fleet weather, 1787–1788

Images: George Raper, 1791, State Library of NSW (SLNSW); Gergis, Brohan and Allan (2010).

William Dawes: Australia’s first meteorologist

• Lieutenant William Dawes maintained a record for three years at Dawes Point (1788–1791)

• Captures the seasonal cycle, shows that the first settlers experienced very wet conditions on arrival in Sydney Cove

• Only analysed in 2008: untouched for 220 years!

Images: Read, Richard (1821), Dawes Battery Point, SLNSW; J.Gergis, Royal Society of London 2009.

28 June 1836

Images: National Library of Australia (NLA, www.trove.nla.gov.au)

1821–1840: Sydney newspapers

• Farmers• Doctors• Explorers• Amateur scientists

Images: Ashcroft; SLNSW; BoM National Library; The University of Manchester; University of Melbourne.

1788–1860: Amateur observers

W.B. Clarke (1798–1878)

W.S. Jevons (1835–1887)

• Governor Gipps ordered convicts to be trained in taking meteorological observations

• They were sent to Port Macquarie, Port Phillip and Port Jackson

Images: George Rowe: Melbourne from Flagstaff Hill, 1858, State Library of Victoria (SLV); NSW Government Gazette, SLV.

1840–1855: Government Gazette

Image: BoM

Data quality

Images: NSW Government Gazette, SLV.

Data problem or extreme event?

Image: Government Gazette, SLV

Data problem or extreme event?

Data problem or extreme event?

Black Thursday, 6 February 1851

Image: William Strutt, Black Thursday, 1851, SLV.

SE Australian temperature 1860–2010

Ashcroft et al. (in review)

Image: Gergis and Ashcroft, 2012 (in revision).

Rainfall stations 1832–2009

SE Australian rainfall stations 1860–2009

• Purple=Instrumental data• Grey=Documentary data

Image: Gergis and Ashcroft, 2012 (in revision).

Eastern NSW rainfall from 1788

Hugh Hamilton, Diaries and Memoirs 1841-Ca.1882 [Manuscript], National Library of Australia, MS 956

• Identifies and examines the impact of weather and climate events on society

• Often uses traditional archival material like newspapers, letters, diaries and government reports

Climate History

Identifying past droughts using documentary records

Image: Fenby and Gergis, 2012 (in review).

1790–1793: Europeans Experience First Drought in Australia

February 1791: ‘The heat was so excessive that immense numbers of the large fox

bat were seen…dropping into the water…many dropped dead while on the

wing...In several parts of the harbour the ground was covered with different sorts

of small birds, some dead, and others gasping for water…From the numbers which

fell into the brook at Rose Hill, the water was tainted for several days…it was

supposed that more than 20 000 of them were seen within the space of one

mile…’ John Hunter (1793)

June 1791: ‘The ground was so dry, hard and literally burnt up, that it was

almost impossible to break it with a hoe; and until this time there has been

no hope or probability of the grain vegetating…’ David Collins (1798)

William Bradley, Sydney Cove, Port Jackson, 1788, State Library of New South Wales, a3461012

Conrad Martens, Bathurst from the west [picture], ca. 1838, National Library of Australia, nla.pic-an2390624.

‘On a nearer approach [I] beheld a wide extent of brown earth, with occasional flurries of dust passing across it; and this was all that remained of the so-vaunted Bathurst Plains! Every blade of grass and every green herb had disappeared during the drought, and a dry desert usurped their place.’

- Louisa Meredith, 1839.

Alfred May and Alfred Martin Ebsworth, Junction of the Murray and Darling Rivers, 1880, State Library of Victoria, A/ S10/ 04/ 80/ 61

• The Murrumbidgee River was ‘low and easily waded’ in January 1838.

• The junction of the Murray and Darling Rivers was ‘quite low’ in March 1838.

• Victoria’s Broken River was ‘no more than a chain of large ponds’ in July 1838.

• In early 1839 the Lachlan River was dry in places. Lake Cargelligo, fed by the Lachlan, was described as a bog.

Conrad Martens, [Landscape with farm building amongst trees] [picture], National Library of Australia, ca.1840, nla.pic-an2390662

Thomas Tourle, Letter Books, 1839-1845 [Manuscript], National Library of Australia, MS 18.

‘Owing to the alarming drought of two years they have suffered dreadfully & have been almost in a state of famine. Wheat is now 30s/ a Bushl.’ - Thomas Tourle, 14 September 1839

April 1839: NSW Governor George Gipps arranges to import 100,000 bushels of rice from India and corn from South America.

In 1839 grain was made exempt from import duties.

Van Diemen’s Land provided NSW settlers with 2000 bushels of wheat seed and 5000 bushels of harvested wheat.

Rising cost of staple goods spread hardship throughout NSW.

Samuel Thomas Gill, [Drove of cattle by pond in the bush] [picture], ca. 1840sNational Library of Australia, nla.pic-an2376899.

• Moving stock to new pastoral runs around the central district of New South Wales.

• Moving beyond the central district of New South Wales into the newly-settled Port Phillip district.

Responses to Drought

‘It was only by having my marching establishment complete, and thus constantly shifting my ground, that I was enabled to keep the stock alive.’ - Charles Hutton, pastoralist.

On Hutton’s arrival at the Campaspe Plains in the Port Phillip district in 1838:‘The ground was exceedingly dry, the grass apparently dead (although after the first rain it grew again most luxuriantly), the water holes very low, and for nine months there was not even a moderate shower to freshen the herbage.’

‘Hearing a most lamentable description of the drought and scarcity of water in that neighbourhood I made enquiry and as far as the report of some very respectable parties can be relied upon I find that these blacks have been forcibly driven away from the only one or two holes that afford water for miles in the neighbourhood of Mount Harris by some of the stockmen, in order that the water might be preserved for the cattle. That they have been threatened and terrified and have been actually seen by some gentlemen gasping for water – the names of the parties concerned I have not learnt.’

Sir William Dixson, 20 June 1840; Letter from J. Allman, Commissioner of Crown Lands at Headquarters, Documents relating to Aboriginal Australians, 1816-1853, State Library of New South Wales. Call No. DL Add 81, Digital Order No. a1893208.

Adaptive Strategies

‘Government undertakings of this nature lead to waste, miscalculation and mismanagement...You will on receipt of this despatch cause the whole of the Corn in store to be sold by Public Auction.’ - Colonial Government, London, 1841