Dear old Bureau of Meteorology up to usual tricks claiming a hottest evah record hot night for Sydney but ignoring the UHI. The record is not worth the paper it is printed on due to the huge urban heat island UHI.
Sydney weather: Overnight temperature is record high for December, BOM says
AWN lets you look around the region and see that the night of the 14th was warmest in the Sydney core stations, Obs Hill 27.1, Airport 27.5, Parramatta 27.5. Note RICHMOND RAAF (067105) at 23.6 further west in the UHI – the record there for Dec is 25 in 2000. The earlier RICHMOND RAAF (067033) 1928-1994 has 25.5 in 1990 as the record Dec night. All pointing to this warm night event being nothing special – unless you want to beat up global warming.
Chris Gillham in Perth has been monitoring mean daily temperatures at Perth BoM sites and says Perth Airport 9021 is a shoo-in to have the coldest September mean since opening in 1944. Perth Metro 9225 in Mount Lawley has only been open from Jan 1994 replaced Perth Regional Office 9034 which commenced 1897 and underwent various moves before ending up in East Perth. Progress with temperature updates can be checked at AWN or the BoM.
Chris has a page discussing the history of various Perth weather stations since 1897. I will update as the final numbers are available and hope to include other Perth region sites such as Pearce – Jandakot – Medina etc It is amazing we can have a month like this in the teeth of the vast Perth urban heat island.
The centre of our largest urban heat island reached 34.2 on 6 Apr 2016 topping 33.9 from 5 Apr 1986.
Other stations I have checked that were open in 1986 were all hotter in April 1986.
Sydney Airport 34.7 on 6 Apr 2016 but 35.7 on 4 Apr 1986
Bankstown AP 35.8 on 6 Apr 2016 but 36.9 on 4 Apr 1986
Parramatta Nth 35.2 on 6 Apr 2016 but 37 on 4 Apr 1986
Richmond RAAF(067105) 36.6 on 6 Apr 2016 but Richmond RAAF(067033) 38.2 on 4 Apr 1986
The ABC TV weather news was beating up Penrith but that station did not open until 1995 and there seems to be no other Penrith station – tough – what liars.
Looking at the state I have checked Goulburn, Condobolin, Cobar, Bourke – the first 3 were all hotter in Apr 1986. Bourke Post Office was hotter 3 times between 1906 and 1922. So just now I can not find that 6 April made a record hot day anywhere in NSW except Sydney Obs Hill – any suggestions? This would be remarkable.
We have all seen the media beat ups about the “Great Four day Perth heatwave 7th to 10th Feb 2016” – never a mention that that the ever expanding Perth urban heat island UHI might contribute to this event. Credit where credit is due though, the original BoM forecast was pretty good. Unlike their Brisbane and Queensland efforts this year.
Check out the statistics assembled by Chris Gillham in Perth – his website has much information on WA and Perth climate matters. Interesting that Perth Airport temperature data shows the “Great Four day Perth heatwave 7th to 10th Feb 2016” was exceeded by several past events at that site.
The Sydney Morning Herald reveals – Sydney area an ‘urban heat island’ vulnerable to extreme temperatures 14 Jan 2016 – It is welcome that such basic facts can be spoken about.
Research by the BoM 15 years ago found measurable urban effects in small Victorian centres Hamilton, Camperdown-Cobden, Colac. The BoM paper can be downloaded as a 216KB pdf-
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.
Ponder these quotes from the BoM to the ABC –
[Bureau of Meteorology forecaster Sean Carson said temperature lows seen this week, along with last August’s extreme run of lows only occurred once a decade.
“August last year saw a pretty impressive run of overnight lows, where we saw eight consecutives nights below -5C, with the lowest night in that sequence getting all the way down to -8C,” he said.
“But prior to that it is probably something we only see every 10 to 15 years where we get such cold minimums.”
Mr Carson said this “impressive” run of temperatures was more common in the 1970s.
“It used to be fairly regular before the 1970s, before we saw a lot of development across Canberra, which did give Canberra a little bit of heat coming from industry,” he said.]
So is the non-urban classification for the Canberra Airport BoM station up for review?
From page 76 of “Techniques involved in developing the Australian Climate Observations Reference Network – Surface Air Temperature (ACORN-SAT) dataset” CAWCR Technical Report No. 049 – BoM March 2012
The BoM Cobar Meteorological Office is adjoining housing on the north edge of Cobar, a mining and pastoral town in remote New South Wales population ~4,000. A BoM MO is professionally staffed.
The Airport is several km away to the SW – these minimum temperature readings for May show a UHI of a few degrees most mornings.
Obviously if mornings are too breezy – the relationship gets perturbed. You can see here that lately there are only light zephyrs in the early mornings when minimum temperatures are recorded.
The BoM classifies Cobar MO as “non-urban” – despite housing a stones throw away. Not on this planet.
Adelaide Now is carrying this news item (HT Chris Gillham) – Weather station near Adelaide High School to more accurately measure climate change will involve cutting 18 Parkland trees
The article says – [The bureau wants to relocate to the Parklands site to be able to make comparisons with historical readings gathered at a previous station which operated near the site between the early days of the South Australian colony and 1979, when the city station was moved to Kent Town.
The data from the new weather station would be able to be accurately compared to historical figures to determine the impact of climate change.]
So the BoM thinks that relocation on this or that postage stamp area of parkland enclosed by the huge and ever increasing urban heat island of the ever expanding and infilling Adelaide suburbs – will somehow mean that “…data from the new weather station would be able to be accurately compared to historical figures to determine the impact of climate change.”
And of course this is the same BoM who thinks Canberra Airport is “non-urban”
Of course you are seeing this in MSM headlines?
Yesterday Sydney barely struggled above 20°C on Australia Day the 26th January 2015 – in the face of the ever growing urban heat island too – 30 minute data preserved – online here – In 1965 the max was 20.7 (ACORN says 20.9) then in 1957 the max was 19.4 (ACORN said 19.6) Daily max and min data – as I write the BoM is slow to update the max for Monday. But Australian Weather News already has Monday the 26th at 20.0