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Jennifer MarohasyI recently wrote to the new Parliamentary Secretary for the Minister to the Environment, Mr Bob Baldwin MP, commending him on the appointment of the new panel to review the Bureau of Meteorology’s official national temperature records.  I make the following three recommendations with respect to methods used to calculate the national average temperature for Australia:

1. Use the same locations when calculating the average mean temperature for different years.  Adding hot stations later, generates its own artificial warming bias.

2. Start the official record from 1880, not 1910, thus including the hot years of the Federation drought (1895-1903).   To suggest this is impossible because there were no Stevenson screens before 1910 is inconsistent with the historical record, which shows there were even Stevenson screens installed a locations in Western Australia from 1880.

3.  Don’t homogenize individual temperature series, changing actual recorded temperatures, unless there was a documented equipment change or site move.  It is nonsense to change the magnitude and direction of temperature trends based on statistical discontinuities with locations in different climatic zones.   Indeed, this was the original justification for changing an overall cooling trend of 0.35 degree per Century, to a warming trend of 1.73 degree per Century, at the Rutherglen Research Station in north east Victoria.

The letter, which relies mostly on Wilcannia as an example of how not to calculate national temperature trends, can be downloaded as a PDF here.


For a list of my scientific publications, click here.  Over recent years I have been published in: Atmospheric Research, Advances in Atmospheric Research, Wetlands Ecology and Management, Human and Ecological Risk Assessment, Public Law Review and  Environmental Law and Management.

I was published every fortnight for about 10 years by The Land newspaper, Fairfax Media Ltd (April 2004 – November 2014).  I resigned as columnist, and also stopped blogging, to concentrate more on my scientific research.  This work  is focused on historic temperature reconstructions and monthly rainfall forecasting.  The two are linked because, with Professor John Abbot at Central Queensland University, I am developing statistical models based on a machine learning technique to forecast monthly rainfall up to 18 months in advance.   The skill of our forecasts is documented in past, and upcoming, technical papers in terms of root mean square errors (RMSE) and mean absolute error (MAE) relative to observed rainfall.  This means that our forecasts could be easily compared in a rigorous and quantitative way against the forecasts from general circulation models including the Bureau’s POAMA.  However, so far, the Bureau has resisted any comparisons being made, as I detailed in a letter to Simon Birmingham in August last year, which can be downloaded here.

Our research on rainfall forecasting and temperature reconstructions is funded by the philanthropic B. Macfie Family Foundation.

For many years I have advocated the restoration of the Murray River’s estuary, and maintain The Myth and the Murray website.

The photograph that features in the top banner was taken by me when I visited the famous Blue Gum Forest in the Grose Valley, Blue Mountains, on 3 February 2008. Contrary to media reporting, the forest had survived the back burning of a year earlier.

At the time I was living in the Blue Mountains. I then moved to central Queensland,  I now live in Noosa.  As well as walking in the national park and swimming in the ocean, I enjoy regular workouts at the local gym, and practice yoga and meditation.


On Line Opinion, Australia’s e-journal of social and political debate, has published me since 2003.  The following opinion articles on a variety of subjects relating to management of the natural environment can be accessed here:

Slots in dyke walls, won’t fix mulloway fishery – 3/06/2014. When Ngurunderi walked across the Murray’s mouth – 7/02/2014.  No increase in warm nights or mild winters at Bathurst – 30/10/2013.  No increase in hot days at Bathurst – 28/10/2013.  Mulloway, not carp, belong in the Murray River’s estuary - 13/08/2013.  FOIA, government-funded climate science and hole-digging – 20/03/2013. Restoring the Murray River’s estuary – 26/03/2012. Great Barrier Reef ‘research’ – A litany of false claims – 10/10/2011.  Carbon tax nonsense – 6/05/2011. Snowy Hydro derivatives play submerges farmers – 17/02/2011.  Snowy Hydro tops up floods with environmental flow – 1/02/2011.  Water Plan will decimate Murrumbidgee frogs – 11/10/2010.  Add salt at the mouth to save the Murray – 6/10/2010.  The battle for the red gum forests – 1/09/2008. Saving the Coorong by restoring its native state – 14/08/2008.  Carbon rationing or freedom – 14/03/2008. John Howard, environmentalist – 24/12/2007.  Rachel Carson: too successful for her own legacy – 28/05/2007. Reef may benefit from global warming – 1/02/2007.  The campaign to stop mining – 15/11/2006.  Windmills are not a solution to this drought – 27/10/2006.  Environment lost in rush to build dams – 7/09/2006. Steve Irwin’s legacy to conservation – 5/09/2006. Democracy versus leadership in Poowoomba – 31/07/2006.  So rich, we can afford to keep ‘Saving the Murray River’ – 10/05/2006. Fat ducks equals fat cows – 18/04/2006.  Costly harvest of ignorant GM campaign – 16/12/2005.  Jared Diamond’s gated community of the mind – 4/11/2005. Let’s eat kangaroo – 23/09/2005. Greenpeace anti-GM campaign doomed- 15/08/2005. No science and no respect in Australia’s anti-whaling campaign – 7/07/2005.  Save the forests: Support evidence-based environmentalism – 6/06/2005. Drip-fed figures – 31/05/2005.  So now Kyoto is a reality, will it get cooler? – 16/02/2005. Beware of doomsday forecasts – 4/01/2005.  The ABS’s environmental statistics reporting fails the basic test of rigour – 29/03/2004.  Beware: everyone in the environment debate has an interest to protect – 13/02/2004.  Received evidence for deterioration in water quality in the River Murray – 20/08/2003.

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