Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Archives for February 2014

Not a Natural Disaster, Just another Rainfall Deficit

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In announcing yesterday’s $320 million drought assistance package for farmers there was some mention of the situation out west being akin to a natural disaster. A more accurate description would be that its part of a natural cycle – not a natural disaster.

There are many reasons why landholders may be particularly vulnerable to this drought, but they mostly relate to government initiatives that have over the last couple of decades significantly eroded the resilience of farming communities, rather than exceptional climate.

We live in a land of highly variable rainfall that has historically experienced regular drought often broken with big floods.

The Bureau of Meteorology has been defining the drought as a rainfall deficient for a 16-month period (October 2012-January 2014) relative to a long-term average defined as the years 1961-1990. So according to the Bureau there has been a severe rainfall deficiencies (lowest 10% to 5% of records) in place across much of inland Queensland, central northern New South Wales and in a small area on the coast of Western Australia near Shark Bay. Also, most of Queensland west of the ranges, northern New South Wales, northeastern South Australia and the southeastern Northern Territory has received less than 65% of the long-term (1961–1990) average rainfall for the 16-month period.

While I am sympathetic to farmers struggling to make ends meet, and I don’t begrudge anyone some government support when the chips are really down, to suggest there is a natural disaster because rainfall is less than 65% of what it was during the period 1961-1990 for a period of a bit over a year is absurd. Australian rainfall

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ABC Rural Reports on New Rainfall Forecast Model

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ABOUT one week after Central Queensland University put out a media release announcing the publication of our latest paper on medium-term rainfall forecasting, John Abbot and I received a phone call from the ABC, from a rural reporter.

Part of the interview with Professor Abbot can be heard online here, http://www.abc.net.au/news/2014-02-21/nrn-forecast/5275122

ABC journalists Cassie Hough and Kathleen Calderwood have also written a short article based on the interview in which they effectively capture the key points, http://www.abc.net.au/news/2014-02-21/nrn-forecast/5275122

And following is a succinct summary of the interview by one of the media monitoring services:

“New research from the University of Central Qld shows medium-term rainfall forecasts may be more accurately predicted by a form of artificial intelligence, which aim to predict the weather through pattern detection, and predicts not what the weather will do day-to-day, but in a month or more. John Abbot, researcher, says he was motivated to do the research after the huge flood at the start of 2011.

Abbot talks about how his research works, and the problems with modern-day weather forecasting systems, and says farmers and mine-operators need accurate data as opposed to vagaries. Abbot says he would like the Bureau of Meteorology take more interest in what he is doing.”

John Abbot

The paper can be downloaded from Science Direct, with full open access available until March 26, here,
http://elsarticle.com/1ej97n3

[Open access until March 26, 2014]

Highlights include:

1. Artificial neural networks are developed to forecast monthly rainfall for localities in Queensland.

2. Comparative utility of input variables, including local maximum and minimum temperatures, is tested in the artificial neural network.

3. The Inter-decadal Pacific Oscillation, IPO, is found to have utility for rainfall forecasting.

4. Artificial neural networks forecasts are superior to Australian Bureau of Meteorology official seasonal and monthly forecasts.

When Ngurunderi walked across the Murray’s mouth

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AUSTRALIA was erroneously considered terra nullius at the time of European settlement. I know this wasn’t a land belonging to no one because there are the dreamtime stories, including the story about the formation of the Murray River. It happened as the hunter of creation times chased the mighty Murray cod downstream, the bends and reaches being formed as the fish thrashed along the channel. This happened a long time before Captain Charles Sturt sailed his whaleboat across Lake Alexandrina in February 1830.

Different indigenous tribes have slightly different versions of essentially the same dreamtime story. According to the Wotjobaluk people of the Wergaia tribe of the Wimmera region of northwestern Victoria, the hunter was named Totyerguil. According to the Yaraldi people of the Lower Murray his name was Ngurunderi. The story of Ngurunderi, as told by Albert Karloan, a council-member of the Manangki clan, Yaraldi tribe, to the anthropologists Ronald Berndt in 1939, is much more interesting, and perhaps much more historically relevant for Australians than anything we might read about Adam and Eve in the book of Genesis.Ngurunderi

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General Circulation Models Can’t Forecast Seasonal Rainfall

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I’ve just published in the peer-reviewed literature explaining:

“Much of the present research effort by government institutions in Australia, which is focused on monthly and seasonal rainfall forecasts, is limited to the application of general circulation models, in particular, POAMA. However, results so far have been disappointing with medium-term monthly forecasts consistently about equivalent to, or worse than, climatology, Table 4. Nevertheless in June 2013, POAMA was adopted as the system for generating the BOM’s official seasonal forecasts.”

http://www.sciencedirect.com/science/article/pii/S0169809513003141
[Open access until March 26, 2014]

In short, the Bureau could better serve the Australian public by just updating and publishing the long-term average rainfall each month for localities for which it has statistics, rather than pretending it can generate a reliable forecast. And I offer the same advice to the UK Met Office which yet again botched its seasonal weather forecast. The following quotes via Benny Peiser at The Global Warming Policy Foundation.Birmingham duck pon

BUNGLING weather bosses predicted a drier than usual winter, it has emerged. The Met Office’s staggeringly inaccurate forecast was made at the end of November last year – just a month before the record-breaking deluge began. And the agency gave just a one in seven chance the three following months would “fall into the wettest category”. On Nov 21, its experts predicted: “For the December-January-February period as a whole, there is a slight signal for below-average precipitation”. The calamitous estimate emerged as Downing Street dubbed the devastation caused by the floods as “Biblical”. –Tom Newton Dunn, Political Editor, The Sun, 11 February 2014 [Read more…] about General Circulation Models Can’t Forecast Seasonal Rainfall

Peer-Reviewed Papers Supporting Skeptical Arguments Against AGW Alarmism

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Wanting to find a list of peer-reviewed papers supporting an alternative perspective on climate change? It’s just been compiled by the geeks at popular technology.net

http://www.populartechnology.net/2009/10/peer-reviewed-papers-supporting.html#Preface

So much for the false statement by Al Gore in 2000 that:

“There was a massive study of every scientific article in a peer reviewed article written on global warming in the last ten years. They took a big sample of 10 percent, 928 articles. And you know the number of those that disagreed with the scientific consensus that we’re causing global warming and that is a serious problem out of the 928: Zero. The misconception that there is disagreement about the science has been deliberately created by a relatively small number of people.”

The list includes 1350 plus papers on a range of topic: [Read more…] about Peer-Reviewed Papers Supporting Skeptical Arguments Against AGW Alarmism

Mining Historical Data to Provide Better Medium-term Rainfall Forecasts

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THERE are at least 3 practical ways in which medium-term rainfall forecasts for Queensland can be improved:Rain drops on water

1. Through the use of sophisticated statistical modelling techniques, in particular artificial neural networks to mine historical data for recurrent patterns,

2. The incorporation of relevant climate indices, including the Inter-decadal Pacific Oscillation, and also

3. The presentation of forecasts as charts showing total forecast rainfall, rather than as coloured maps with assigned probabilities.

And there is a fourth suggestion, also detailed in the recent paper by myself and John Abbot that has just been made available for free download by Elsevier, publishers of the journal Atmospheric Research.

The link is here: http://elsarticle.com/1ej97n3

Free access will only be available until March 26, 2014. Enjoy!