Geoscience Reference
In-Depth Information
comments that river stream flows would drop away quickly. Long's forecast was
remarkably accurate. On 25 September the Bureau was forced to issue a revised spring
forecast, this time forecasting below average rainfall for the Murray Darling Basin.
The Bureau's forecasts are derived from the Predictive Ocean Atmosphere Model for
Australia (POAMA). The output from POAMA is generally consistent with what is known
of rainfall forecasts from other GCMs. They fail to reproduce the observed historical
worse than the forecasts a school child could generate based on simply calculating the
monthlymeanrainfallforaparticularlocalitywithapencilandpad.Suchanaveragevalue
is known as climatology. But the scientists at the Bureau are so committed to GCMs that
in May 2013 they discarded the old statistical models relied on for the past twenty years,
and adopted POAMA as the basis for all climate forecasting. There is no peer-reviewed
paperthatindicatesPOAMAcanreliablyproduceaseasonalormonthlyforecastwithmore
skill than the old statistical method—because it can't. Indeed the peer-reviewed literature,
consistently outperform GCMs such as POAMA.
Meanwhile many climate scientists seek to minimise the potential error of their GCMs
forecastsbypromotingaveragevaluesfrommultiplemodels.Theseareoftenreferredtoas
ensembles. The
Fifth Assessment Report
(AR5) of the Intergovernmental Panel on Climate
Change (IPCC), in its conclusions on 'impacts, adaptation and vulnerability' released in
March 2014, included rainfall forecasts for almost every region of the world. The forecasts
were developed by averaging output from more than 50 different GCMs. It's a mammoth
undertakingandsoit'sdoneinstageswithresultspublishedinthepeer-reviewedliterature.
IfweconsiderresultsjustfortheMurrayDarlingBasinintermsofoutputfrom27different
models run by key institutions across the globe including the Bureau, each contributing
to the fifth phase of the Climate Model Intercomparison Project, it is evident that some
models predict a large increase in rainfall, while others predict a large overall decline in
GCMs should be reason for great concern, and for the discarding of the models altogether,
but instead the scientists choose to combine the irreconcilable and thus arrive at a single
figure claiming a two per cent decline in rainfall for the Murray Darling by 2090!
Some claim Ken Ring is running a weather prediction scam because he uses the moon
to inform his rainfall forecasts. Yet it is not disputed by those with an understanding of
conventional physics that the moon's gravitational field, along with the day and night
cyclegeneratedbythespinningearth,createsatmospherictidesthatmodulatehigh-altitude
winds that have a major influence on weather. We have seen no independent assessment
of the skill of Ring's predictions, but he sells many hundreds of his weather almanacs to
Australian farmers each year. Indeed if there is a scam, it is being run by the Bureau, not