In the BoM “SPECIAL CLIMATE STATEMENT 27” – An exceptional summer heatwave in greater Sydney and the Hunter Valley – the BoM on page 10 shows the following graphics of Sydney night-time temperatures increasing since 1859.
The existence of an ever increasing urban heat island (UHI) in Sydney – and all other urban areas – is completely ignored in SCS27.
What an unscientific disgrace the BoM is becoming.
I wonder whether that BOM paper on UHI referred to here www.climateconversation.wordshine.co.nz/2010/11/the-bom-discovers-uhi/
has been published or made public
Warwick you have a comment there saying ‘….It will be interesting to see the “Urbanisation and maximum temperature” paper by – Harvey Stern1, Belinda Campbell1, Michael Efron, John Cornall-Reilly1, and John McBride2.
– when it emerges peer reviewed and published.
Of course I doubt any of us common herd will ever get to examine their ADAM data.
On the face of the authors statements there seems to be some conflict with the very influential 1996 work of Torok & Nicholls which heavily corrected BoM data leaving an IPCC compliant warming trend…’
Have you heard any more about that paper
If an undergraduate student had compiled a report like that on Sydney with no reference even to the possibility of the UHI effect on night-time temperatures I would have marked him/her WAY, WAY down. The PhD’s responsible for this travesty are a disgrace.
Warwick
The formal request for a Data Audit will most likely test the nerve of a few of the BoM Mandarins.
joannenova.com.au/2011/02/announcing-a-formal-request-for-the-auditor-general-to-audit-the-australian-bom/
and further to pattoh’s comment Ken Stewart has a new post:
Official reply to my queries at last!
By kenskingdom
Here is the complete text of the reply to my letter of 26 October 2010 to Tony Burke MP, the Minister responsible for the Bureau of Meteorology amongst other things. Dr Ayers also included a hard copy of the Jones et al. paper referenced below.
I also include below for the public record previous correspondence with BOM.
kenskingdom.wordpress.com/2011/02/21/official-reply-to-my-queries-at-last/
Is it the case that the fingerprint of the UHI effect includes a greater increase in night time temperatures than for other attributable sources?
Yes – I agree a lot of data does show that UHI’s night-time temperature trends warm more than the day-time trends. Due IMHO to the steady increase in mass of heat trapping human construction in cities over century long timescales that retain day-time heat to be released at night. This graphic compares long term trends in night-time temperatures between Melbourne and Rutherglen. Sydney would be similar.
The exceptionally warm conditions were partly due to a blocking high in the northeast
Tasman Sea which remained semi-stationary between January 29th and February 6th.
…. The position of the sub-tropical ridge, combined with the high pressure
system in the Tasman, prevented the progression of cool air masses into the state.
This high also was responsible, so I am told, for Yasi taking the almost straight line path to the coast.
Maybe the burghers of Townsville should erect a monument to this unnamed “High”?
does anyone know whether any adjustments are made to the BOM’s raw data
I saw this comment here by Scott wattsupwiththat.com/2011/02/21/an-analysis-of-australian-rural-vs-non-rural-stations-temperature-trends/#comments
The data you can download from the BOM site is modified. Shamefully they call it ‘raw data’
Just asking …
It seems that the Perth UHI is taboo and not worth mentioning either.
“does anyone know whether any adjustments are made to the BOM’s raw data?”
I recently took the trouble to cross plot BOM’s temperature records for a sample of stations against the raw data available from GISS with interesting results. Warming trends appear out of nowhere (average 0.59degC/century)! The stations I chose were selected on the basis of broad geographic distribution and long, stable records, with a mix of rural and urban sites (honest, I didn’t peek at the results until the end of the exercise). Does anyone know why all records on BOM’s website start in the year 1910 regardless of station history?
I believe 1910 was chosen because they assumed by that date that all stations had Stevenson Screens, despite the fact that many had been using them for around 20-30 years.
Tezza – My 1995 paper looks at proceedings from the 19th Century Intercolonial Conferences and it is clear the Stevenson screen was in widespread use – particularly at high order stations.
Other Southern Hemisphere regions show this late 19C warmth, NZ, Fiji, far sth Sth America and the African station Bulawayo – an Observatory with data from 1897.
In recent years archives are putting online many photographs of late 19C Stevenson screens in use – Distortions being spread about Australian meteorological history – and also many newspaper archives carry articles from the late 19C evidencing widespread us of the SC.
Warwick, this information aie.org.au/Content/NavigationMenu/Resources/EnergyData/Temperature_Distrib.htm on Melbourne temperatures is presented in an interesting way. The distributions look like Poisson distributions. I have found that rainfall in my area is close to a Poisson distribution which with enough data should allow the probabilities of high rainfall events to be calculated. The AGW believers have pointed to some extreme events (or supposed records) but these need to be put into context particularly when considering short time spans.
Not sure the time span of the data as the highest (BOM)daily temperature in January was on 13/01/1939 45.6C, in February 07/02/2009 46.4. I also remember the hot spell 17 to 19 Jan 1959 when the temperature was over 100F all day and night (BOM max. 42.6,41.8, 42.8 C resp).
Have you noted similar distributions?
Keep strong