UNE's Dr Robert Baker thinks this drought was predictable, and based upon the Sun's past behaviour and its relationship to rainfall patterns in Australia, those conditions could continue for a few years, but it did not necessarily mean there would be no rain at all.
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Earth's climate system is experiencing a centennial minimum in solar activity, Dr Baker said it would be wise for regional Australian communities to conserve as much water as possible.
"Every 100 years the sun becomes more passive and that has big implications. So, this drought is most likely a one in a 100 years event," he said.
"If you go back and have a look at the 1900 Federation Drought, there have been similar patterns that have been repeated in the last decade.
"Also back in the 1800, when the Dalton Minimum was at the beginning of the 19th century, newspapers were reporting drought during that time in Sydney. Now that is only one point, but it is interesting that that pattern repeats itself."
... in terms of managing water supplies in Armidale, you would say, 'Yes we have to be prudent.'
- Dr Robert Baker
Solar minimums are not new, the Maunder minimum in the 1640s (when a 14-year ice age reappeared and the Ming Dynasty fell) and the Spoerer minimum from 1405-22 are another two of the more well known events. Such events do extend backwards in time.
Dr Baker said his work was not about temperature.
"All my work is about rainfall," he said.
"I looked at the data the other day and the Pacific Index correlates with what's happening to the Sun at this point. All my work would not work if there was no correlation between what's happening in the Sun and what's happening in the Pacific.
"The Sun is an integral part of climate change, which is not really taught at present."
He said by using the SOI, paired with the progression of the sunspot record, it could be shown that during the early 20th and 21st century time series the SOI was tracking similarly on both occasions.
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The comparison allowed for this drought to be predicted, and for management strategies to be adopted before its onset and Dr Baker thought it also allowed for the prediction of future drought events, their severity and extent based on the solar minimum event.
"There is still randomness, and so farmers who want to know if it is going to rain on their property ... You just cannot do that. I guess it's just the physics of the chaos theory," he said.
"But you can try to look at the seasonality. Does that mean you're going to get no rain? No, but looking at the past, you're not going to get two years of good [rain], and there are going to be times that you do get average or above rainfall.
"So, the likelihood of the Murray Darling basin being refreshed in the next five years, I would say is low, however, in terms of managing water supplies in Armidale, you would say, 'Yes we have to be prudent.'
"If it does bucket down in the winter we don't lift water restrictions altogether."
You can hear more about Dr Baker's work from 1pm-2pm on Thursday, May 23 in the Co2 Lecture Theatre, Earth Sciences Building at UNE as part of a free seminar series being given. For more information phone 02 6773 2884.
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