#2 Ongoing BoM utter incompetence
October 3rd, 2010 by Warwick HughesThis time we show the huge divergence between the September quarter Rainfall Outlook – and the actual rainfall deciles for the same period.
Clearly the BoM have near zero predictive skills over 1 to 3 months out – any minor agreements are probably due to chance.
Yet our nations policy on carbon emissions will be built assuming the BoM and their supporting pro-IPCC orgs have predictive skills that compel our GreenLabor Govt to believe we will be seriously warmer over the coming century.
We are told by the BoM that September rainfall could be an all time record for Australia. Note this surreal article in the Sydney Morning Herald which starts by saying, “Global warming may have given Australia its wettest September in more than 100 years, but “extreme dry years” lie ahead, the Bureau of Meteorology says.”
This seems to me to be in contradiction of the facts as reported by weatherzone.com.au who say, “After their coldest winter in 13 years Sydney residents have just experienced their coldest September in five years..”
I have heard the BoM on TV news saying in effect, “September 2010 rain was an anomaly – we are really still in a dry spell and headed for dryer times”.
That seems to be the drift of their recent “Special Climate Statement 22″ – I am suspicious of their Fig 3 in SCS22 and would like to see data back to pre 1900.
Time will tell if the BoM is right to say – “extreme dry years” lie ahead – but IMHO some sections of the BoM are stunningly incompetent and only mass sackings and a re-focus on their observing network would make the BoM relevant to Australian needs.
Posted in BoM Australia | 6 Comments »
October 4th, 2010 at 3:02 pm
Warwick
Personally I am a believer in the solar cycle/sunspot/solar magnetic field effect on cosmic radiation & therfore cloud formation.
The last real ground moisture high where I am was for the 1997-1998 season. Was that around the end of the previous cycle?
Perhaps the black conical hats in favour down at BoM have “$” symbols instead of stars, suns & moons.
October 5th, 2010 at 5:08 pm
Do you have any basis for your “stunningly incompetent” line?
So far as I’m aware the BoM has one of the best forecast records of any country.
I didn’t see you congratulate them when they got the Victorian floods predicted almost perfectly a week out!
Weather prediction is *hard* and due to the mathematics of chaos, inherently probabilistic.
What you don’t see on the news is the non-major probabilities: you only get the “best chance” so as to keep things simple for the public.
If you think that short term inaccuracies are such an issue consider this: An insurance company has no idea if/when you will have a car accident…but for a million drivers the accident rate is *very* predictable, which is why insurance companies can make money.
In a similar way *climate* is more predictable than weather.
I can assure folks that the BoM folks are not doing this for big $$$…look to banking and real estate for that sort of greed. they are just trying to do a difficult job as correctly as possible.
BTW. I don;t remember this sort of attack prior to the paid for GW denialist movement. Does it feel good to join the likes of Big Tobacco in deriding science for profit?
October 9th, 2010 at 9:57 pm
Warwick,
WA Water is advertising that we had a record lack of rain to fill our dams this winter – seems we have had plenty of rain but most of it seems to have flowed into the sea missing the dams. Right now it is rainy.
October 10th, 2010 at 2:27 am
Richard Kelly from Queensland has sent me his paper:
“Predictions Forecasts or Just Pure Guesses”
where he checks the success rate of BoM weather forecasts for Brisbane.
Well worth a read.
October 17th, 2010 at 3:45 am
Maybe Andy should ask Richard Kelly to send him his data (as reported by WSH above).
Richard does not give such a glowing report on BoM predictions.
“…. I’ve been monitoring the Brisbane Bureau’s 24-hour temperature forecasts and
actual temperatures for a total of 2834 days (over 7-3/4 years). So how have they managed to perform?
In 2834 days, they’ve managed to predict both the minimum and maximum temperatures correctly on only 239 occasions – approximately one day in 12 (or 8.4% of the time). The average total error in their predictions was 2.4 degrees, whilst their maximum error was 9 degrees!”
Now if the BoM are the gold standard in temperature predictions, one must assume that a prediction of a global average temperature in years and decades ahead will be nigh impossible. From geological and historical past data, the Earth will do it’s thing and we won’t have any control of it globally.
November 14th, 2010 at 7:07 pm
CGM’s how accurate are they?
www.informaworld.com/smpp/section?content=a928051726&fulltext=713240928
A comparison of local and aggregated climate model outputs with observed data
Authors: G. G. Anagnostopoulosa; D. Koutsoyiannisa; A. Christofidesa; A. Efstratiadisa; N. Mamassisa
Abstract
We compare the output of various climate models to temperature and precipitation observations at 55 points around the globe. We also spatially aggregate model output and observations over the contiguous USA using data from 70 stations, and we perform comparison at several temporal scales, including a climatic (30-year) scale. Besides confirming the findings of a previous assessment study that model projections at point scale are poor, results show that the spatially integrated projections are also poor.