I have been digging into my archives and have discovered some of my temperature data downloads from GISS with their tapered UHI adjustments. Here is their work for Melbourne.
Do any readers remembers those efforts by GISS ? I have several more examples I can show later that essentially adjust strongly warming city data to show a near neutral trend. Maybe these tapered UHI adjustments (click for chart of exact adjustments) did not please everybody because post 2000 GISS started making homogeneity adjustments using satellite night lights – I am not sure if that method is still used. In recent years I have tended to lose track of what they do once they started adjusting rural data to agree with UHI affected cities.
Just noticed this HT Graeme No.3 – But today I see Adelaide (Kent Town) recorded 7.9°C which just beats the previous record of 8° in 1987 – data starts 1977.
Parafield Airport had 5.7 this morning – Only 0.1 above the December record minimum of 5.6 in 1995. All in the face of the increasing Adelaide urban heat island (UHI) influence.
Adelaide West Terrace 1887-1979 recorded 6.8 in 1955.
I saw this referred to on media – Sydney has its coldest winter in decades – Checking the facts for Sydney Observatory Hill which averaged 7.2°C 1st to 15th July 2015 – I find the next coldest 1st to 15th July was 6.2 in 1971 a 44 year record which is amazing in the face of the ever increasing largest urban heat island (UHI) in Australia.
A bone chilling 4.1C in Tuggers – data started 1996 so a 20 year record.
The AWN page and the statistics for TUGGERANONG (ISABELLA PLAINS) AWS 70339
How can this happen when we are all suffering from global warming ?
Keen eyed readers warned me of this news – Warmest June temperatures for Perth
Working down this station list for the Perth region – In a few days the June 2015 archive will be visible. I have the page saved offline if anybody wants it emailed. Badgingarra had 20.6 last month but in 1985 saw 20.9.
Garden Island had 19.9 equal with 2006. Gingin Aero has 20.9 but saw 22.9 in 1996 and 21 in 2000. Karnet had 17.8 but saw 18.1 in 2006. Rottnest Island at 19.7 was equal to 1997.
Looking around at other stations some closed – Guildford Post Office saw 21.3 in 1944. Upper Swan Research saw 21.6 in 1983. Rottnest Lighthouse read 20.2 in 1949.
I ask if you could take out a century of urban heat island UHI growth – would the BoM claim stand up? I think on balance no doubt last month was very warm in Perth but the claim of “warmest ever” is not the most robust of claims to trumpet from the centre of a huge urban area.
Really strange misinformation – the facts are very simple – Canberra is having a record run of cold nights for this early in June. Yet today the ABC reports – Canberra’s extreme run of overnight lows ‘only seen every 10 to 15 years’ – What is the BoM smoking. Yesterday the Canberra Times quotes the BoM to write – Canberra weather: Cold, frosty mornings to continue before a warm long weekend – Same style of obfuscation – avoid admitting a record at all costs. The Fairfax article confuses Monday and Tuesday – talks of warm weather to come. And there is this odd mention of last August that has nothing to do with anything. Weird mention of “every 10 to 15 years” – no it is the coldest run of nights this early in June for 76 years!!! Then they throw in El Nino to appear all-wise. And our national policy is affected by the org generating this evasive twaddle.
Here is a Table of sorted June minimums for Canberra down past minus 5.1. The record to break is – Tuesday the 2nd -7.0, Wednesday the 3rd -5.1, Thursday the 4th -6.9, all time record run of cold minimums this early in June. Case closed.
At least -6.5°C this morning – we will see official figure later – In 1987 both the 1st and 2nd June read -5.1 which was the previous record. In the face of the growing Canberra urban heat island UHI.
The Courier Mail reported 22nd April – Several Queensland towns hit record low April temperatures.
Hughenden Airport broke the coldest night record including the Post Office – on the 22nd April – and then broke that again on the 27th.
Maryborough saw the same pattern with 6.2°C on 22nd and 5.5 on the 27th both breaking the previous record from 1966. Clermont Airport broke the Post Office record with 4.3 on the 27th – the Post office saw 4.6 in April 1999.
On April 30th Kulgera in southern NT had a record April low of 1.5.
Alice Springs on 1st May hit 1.6 making it the coldest 1st of May since 1881 or whenever the Post Office commenced.
On the 14th Eyre in WA hit -2.5 a record low.
The Courier Mail reports on the 14th – Brisbane wakes up to chilly morning as southerly change pushes dry air and cold winds –
On the 15th Tamworth AP read -4.5 a record low.
On the 16th Broome AP read 7.7 an equal record low.
On the 16th West Roebuck (near Broome) read 5 smashing the previous record of 7.
On the 16th Marble Bar read 7.5 smashing the previous record of 9.4.
On the 25th Newman AP daily max 14.7 smashing the previous record of 16.
Imagine the BoM media releases if the above were all warm April & May records.
If anybody knows of other records – comment or email them – thanks.
A reader has sent in these maps observing some features live on from year to year. “Compared to 2014, west of Strasbourg is more or less the same in 2013, and there is another one near Manosque, northeast of Marseilles, repeatedly. The Paris heat island is in all of them, and the last 3 years Chalons en Champagne is always too cold and inland from Brest too warm.” I agree the French data looks poorly calibrated – will try and get a new 2010 map with the same normals period as the others.
2008 – 2009 – 2010 – 2011 – 2012 – 2013 – 2014 –
This is the second episode in the Cobar ACORN-SAT series examining BoM adjustments to the CDO temperature data – here I start to look at adjustments to minimum temperatures. The 1st episode looked at maximum temperatures. A list of ACORN adjustments to Cobar data is here and you can see the first min adjustment listed is 1st Jan 1972 meaning the adjustment factor applies to all data earlier than that. You will see it is labelled as “Statistical” meaning there is no evidence for it in station diaries or admin records but it derives from computer driven comparisons sifting data differences from multiple stations as far away as Parkes and Hillston – see map. In this case of the 4th adjustment the following stations data was used.
Making the chart of Cobar annual minimum temperatures compared to ACORN-SAT my eye was caught by the adjustment starting in 2006 and affecting all earlier years which I have marked with a blue 6. That is unlisted in the ACORN-SAT documentation and is substantial at about -0.4 degrees C. The slight mismatch between Cobar Met Office and ACORN from 2007-2013 is due to rounding differences because I have made my ACORN annuals by averaging a year of daily data which I leave as produced by Excel with multiple decimal places.
The next adjustment to look for is at 1971 where I have the blue 4, which is the 4th adjustment in the ACORN list and is listed at -0.49 degrees C. The increased departure of ACORN cooler than Met Office to about -0.9 is obvious on the chart.
Examining this adjustment in greater detail I have made a chart comparing Cobar MO and ACORN version with nearest neighbours Bourke, Wilcannia and Nyngan. The average difference between the 1971 & 1972 readings for these 3 stations is +0.2 at Cobar MO, +0.4 at Bourke PO, +0.4 at Nyngan, and -0.4 at Wilcannia, an average for the 3 Cobar neighbours of +0.13, not very different from the +0.2 that we know happened at Cobar Met Office. But instead of leaving the higher quality Cobar Met Office readings well alone – what does the BoM decide to do with their adjustment #4? They take off 0.49° making the 1971-1972 difference now 0.7 – greater by 0.3 than any of the neighbours. Presumably the BoM justify this by their computer driven comparisons with sites as distant as Parkes.
If the reasons for an adjustment can not be seen in nearest neighbours then it must be an exercise in fantasy to search for a reason in a cherry picked array of more distant stations which are all of poorer quality than Cobar Met Office.
It is interesting to check the differences in annual minimums between Cobar Met Office and Cobar Airport which are only about 7 or 8 km apart. You might expect them to be very similar and in lockstep – not so from the chart.
Note the BoM never refer to Cobar Airport data in ACORN-SAT – but we are free to check it out.
First there is no evidence here of a step or jump around 2006 – 2007.
While there are such wildly varying and apparently random differences between these two very adjacent sites – what on earth can the BoM learn by comparing Cobar with Parkes – or indeed any other station in their adjustments list.
These are the sort of unsafe foundations that pro-IPCC climate science is based on.