Guest essay by Cameron Goodison
Recently the Australian Goyder Institute released a report detailing the effects of climate change on rainfall in South Australia. The result:
‘Climate change will halve inflow to SA’s biggest reservoir.’
The ABC, http://www.abc.net.au/news/2015-02-17/climate-change-will-halve-inflow-to-sa-biggest-reservoir-mount-/6128832
To make such a alarming statement one would think the ABC has done its research. They must have first done a quick Google search of the average annual rainfall for the region to see if there is any sort of noticeable downward trend that would give such a statement some degree of credibility.
Ok now we’ve found a trend we should probably read the report in full so we can find see if the methods used appear to be somewhat reliable. Firstly let’s see what data the report used.
Stream flow records for the catchment. They are scientists so they probably accounted for changing usages by humans and changing inflows from the Murray river pipeline.
Rainfall records. 93 rain records are found in the catchment area but the scientists have decided to use only 23 as the others appear to be unreliable and these particular 23 seem to be spread out nicely. Oh and they are using data from 1970 onward too so the scientists must agree that anything before then is unreliable.
Ok so the ABC have done their research and all the data appears to be reliable. Next what is the method used for making the projections??
Well the report says they used a CIMP5 model and combined it with a Markov model and a hydrological model and well the words are starting to get a bit big now so everything in the rest of the report is probably right. And we won’t the question the motives of the Goyder institute which relies on climate change for its very existence.
So now the ABC has some science for its report they should probably go ask some politicians what they think. The Environmental minister says the report justifies his governments 1.8 billion dollar desalinisation plant which is costing 1 million dollars a day to produce water which currently isn’t needed. And so the ABC now has its typical climate change article in which the world is ending and we can only be saved by clever politicians, spending billions of dollars and a non-biased government funded media outlet.