The search for water inland

Australia has an erratic climate, detailed in official records that have been kept over the last 100 or so years.

However an Australian Research Council project called SEARCH (South-East Australian Recent Climate History) is working to backfill knowledge about our climate prior to 1900, by collating climate references from historical documents.

Research team member and environmental historian Don Garden is tasked with interpreting information about Australia’s colonial climate.

He says that for reasons that are not fully understood, the years 1815-16 were a time of extreme rainfall.

“Newspaper records from the time show major floods occurring in Tasmania and NSW, with the Hawkesbury River often in flood and Lake George near Canberra at record high levels,” Associate Professor Garden says.

The abundance of water in that period may have been one of the contributing factors in the ‘search for the inland sea’, a compelling narrative of colonial Australia, and one of the great quests of early exploration. 

“An inland sea or major water source was a logical expectation for early Australians, based on knowledge of the earth at that time,” Associate Professor Garden explains. “Other continents that experienced good rainfall were found to have inland lakes or seas, or major riverways that emptied into the ocean.”

The period of wet co-incided with the first major attempts to explore beyond the eastern seaboard, with explorer John Oxley leading an expedition to survey the Lachlan River and push into western becoming bogged down in wetlands.

“The encounter with these huge morasses and great quantities of water moving inland confirmed in Oxley’s mind that the inland would be wet,” Associate Professor Garden says.

And indeed maps exist in collections detailing expectations of eventually uncovering a large inland watercourse coming into the country from the north-west, via the Ord and through the Northern Territory (eg Maslen’s mythical map, left).

As the country emerged from this wet period other explorers set forth, with Charles Sturt able to use this drier time to push out to the Darling. His expedition eventually established that the Murray Darling river system did flow out to the sea, but not in the grand manner of other great watercourses, instead being swallowed up in Lake Alexandrina and not delivering on the grand expectations of the explorers’ imaginings.

“What they found finally was an arid interior. The myth of the inland sea was once and for all broken – the search given up,” Associate Professor Garden says.

 “By the late 1820s a period of severe drought or El Nino climate was moving in, and with it the creeping realisation by the early expansionists and authorities that we live in a very dry land, and a difficult climate for agriculture, with unpredictable weather and depleted soils.”

Associate Professor Garden says the energies of the early explorers were not, however, wasted.

“They may not have found the fertile interior and reservoirs of fresh water they had hoped for, but they did uncover vast pasturelands the length of the country – made accessible once a crossing of the Blue Mountains was established.

“Finding this vast area of open grassland was a formative discovery, allowing as it did for the development of the pastoral industry on which the nation’s economy was largely built.”

http://www. climatehistory.com.au/