On the night of the 11th-12 of Jan 2010 Melbourne sweated through an uncomfortably hot night. Just a couple of media refs will give you the gist but Google could find more no doubt. There is talk of Melbourne’s “..equal hottest night ever.” But I see no sign of balancing statements which should have refered to two facts.
[1] The record equal temperature was measured in the centre of the Melbourne urban heat island (UHI) which has grown at night by 2 degrees centigrade in the last 60 years.
[2] The BoM should have stated that there was little sign the hot night was a record breaker outside of Melbourne.
This BoM map shows the minimum temperature anomaly for the 12th Jan.
Click for the full Australian map.
You can make those maps here.
To test how widespread record breaking temperatures were that night I checked 11 sets of station data and found only one with a record high minimum on the 12th. Note my daily data is only updated to April 2007, so the true rankings might be even lower if there have been notably hot nights in the 32 months since then.
Rutherglen from 1965, 23.5 min on 12th, there were 50 FIFTY hotter nights from 1965 to April 2007 , so it ranks 51st
Ballarat from 1957 , 24.6 on 12th, ranks 6th
Castlemaine Prison from 1966, 28.5 min on 12th was hottest night since 1966 The single hot night record for the BoM !!
Ararat Prison from 1969, 25.5 min on 12th, 2 hotter nights, rank 3rd.
Echuca Aero from 1957, 28.5 min on 12th, would rank 5th
SWAN HILL AERODROME from 1996, 26.6 min on 12th, ranks 7th
SWAN HILL Post Office from 1960 to 1996, assuming same min as Aero, ranks 9th
Horsham Aero from 1997, 226.2 min on 12th, ranked 3rd,
Mildura Airport from 1946, 29.8 min on 12th, ranks 8th
Mildura Post Office from 1889 to 1949, assuming same min as AP, ranks 10th
Note that 6th Jan 1906 was 50.1 in the day, 35.6 at night then 50.7 on the 7th. But in those days people just got on with coping, they would not have had a Government that lied to them about the climate.
Hay (Miller St) from 1957, 30.3 min on 12th, ranks 3rd
Text of ABC 7.30 Report TV show for 12 Jan
www.abc.net.au/news/stories/2010/01/12/2790181.htm
Dead heat: Melbourne endures record-equalling overnight temperatures
Posted Tue Jan 12, 2010 8:04am AEDT
Updated Tue Jan 12, 2010 10:47am AEDT
The Weather Bureau says Melbourne has equalled its hottest-ever night.
The mercury slid back to 30.6 degrees Celsius by 9.00 am (AEST). (ABC TV: Chris Keane)
Melbourne has recorded its equal hottest night ever.
The mercury hovered above 34 degrees for most of the night, but slid back to 30.6 degrees Celsius by 9.00am.
That’s the same as the previous warmest night in February, 1902.
The Weather Bureau’s Terry Ryan says the city is heading for a top of 40 today.
“We’ve had a cool change through, another one is expected around one or two o’clock,” Mr Ryan said.
“The temperature should rise before that change comes through.
“It should get back up into the 30s well and truly, but we’ll have to see how close to 40 we get later on.
“But it’s definitely becoming cooler this afternoon, then by six pm it will be about 24 or 25 degrees Celsius.
“So a much better day to come once this change comes through.”
Train services cut
The extreme heat is taking its toll on Melbourne’s train network, with commuters facing a second day of delays and cancellations.
Maintenance crews have worked through the night to repair faults that disrupted up to 200 services yesterday.
Power failures caused delays on the Alamein and Glen Waverley lines this morning as well as a handful of other cancellations.
Despite the disruptions, Melbourne’s Lord Mayor Robert Doyle has praised the city’s new train operator, Metro Trains.
Mr Doyle says Metro has coped well in the extreme heat.
“I pay great tribute to Metro,” he said.
“I’d rather see Metro out and getting the trains running than giving passengers ice-creams.”
“I think that’s a far more practical approach to getting people into and out of our city.”
But Mr Doyle says Melburnians may have to get used to train disruptions during summer.
“Prolonged hot temperatures are extreme weather events and it’s going to put our transport system, our communication system and our office system under stress,” Mr Doyle said.
“The important thing is that we all understand that we need to work with that and we need to get through it.”
Metro Trains spokeswoman Lanie Harris says staff have been trying to limit the disruption to services.
“We do hope there will be a smoother run today,” Ms Harris said.
“We certainly have all our resources on call, and we’ll be working as hard as we can to minimise disruption.”
Power outages
Meanwhile, electricity crews are trying to restore power to three-and-a-half thousand households in Melbourne’s north and east.
Heat-related problems have cut power supply to homes in Croydon, Watsonia, Eltham, Epping and Ferntree Gully.
SPAusNet spokeswoman Natasha Whalley says it could take most of the day to get the power back on.
“Crews have been out working since six o’clock this morning,” she said.
“Hopefully we’ll gradually start to get people’s power back on as the day progresses, but in some instances it may take most of the day to get through all of those customers and get everybody’s power back on.”
Health warnings
Health authorities are urging Victorians to take basic precautions against the heat.
Temperatures are again forecast to exceed 40 degrees Celsius in some parts of the State today.
Yesterday, ambulance officers treated about 100 people who collapsed or suffered heat exposure.
Victoria chief health officer, Doctor John Carnie, says people should make sure they drink plenty of water and try not to over-exert themselves.
“Spend as much time as much time as possible in cool surroundings,” Dr Carnie said.
“If your home is not cool then try to get to a shopping centre, a cinema, a library or a community centre where it’s cool.
“Certainly avoid strenuous activity and certainly never leave anyone in a closed, parked car on hot days.”
I don’t understand. The official minimum for Melbourne was posted as 24.2C at both Weatherzone and BOM at
(www.bom.gov.au/climate/dwo/IDCJDW3050.latest.shtml).
Why the discrepancy or what am I missing?
It is puzzling Ian, the Australian Weather News site, click on region 86, has the 24.2 figure ? In fact eyeballing up and down this AWN page, only Melbourne Airport has a really hot night. Perhaps some other Melbourne region sites have picked up errors – or maybe the scorcher night was even more confined to the core of the UHI than I thought.
The BoM Latest Weather Observations for the Melbourne Area;
click on Melbourne then scroll down to morning of 12th, has this for 9am on the 12th, [12/09:00am 30.8] which is I assume where their record equal number comes from. There is no sign of a 24.2 figure at this page.
Somebody should buzz the BoM tomorrow to question the discrepancy between;
Latest Weather Observations for Melbourne
www.bom.gov.au/climate/dwo/IDCJDW3050.latest.shtml
and
Melbourne, Victoria
January 2010 Daily Weather Observations (DWO))
www.bom.gov.au/products/IDV60901/IDV60901.94868.shtml
Perhaps the BoM web pages have grown so voluminous that some parts do not know what other parts are doing. Having these two sets of pages does at first glance look like duplication.
I do know that in Geelong AP (at Mount Duneed on the Surf Coast Highway, about 10km from city centre, with no wind and in a semi-rural setting)on that morning (1am, 12th Jan) the min temp was 21.9C:
www.bom.gov.au/products/IDV60901/IDV60901.94857.shtml
This followed the hot day (11th) when Geelong AP recorded the state’s highest temp (again, not a January record)of 44.9C www.australianweathernews.com/news/2010/100111.SHTML
The 21.9C minimum is way below the high min record of 24.2C set in 1979 at North Geelong (near Corio Bay). So the BoM statement about Melbourne certainly doesn’t apply to the Geelong Region – in fact their statements rarely do.
BOM is changing the URL style to reflect better the locaton. eg www.bom.gov.au/products/IDV60901/IDV60901.94868.shtml is the same as www.bom.gov.au/weather/vic/observations/melbourne.shtml at the moment but the less user friendly versions are being phased out
Noticed a report at Weatherzone at
www.weatherzone.com.au/news/victoria-heat-ends-with-sweaty-night/13577
which I suppose explains it all. Of most interest is this:
“Melbourne finally dropped below 40 around 8pm, was still above 35 after midnight and did not fall below 30.6 degrees all night.
Melbourne’s official minimum was around 24.2, set soon after 9am the previous morning.’
So we can never really know if this was the one of the hottest nights on record because there would not have been such accurate hourly records during the night back in earlier years. They are comparing records which can not be verified – comparing ‘apples to oranges’.
And looking at Melbourne record daily temps for January at
www.earthsci.unimelb.edu.au/~blair/extremes/melbourne.html
24.2C is hardly precendented at all.
Thanks for this Ian, it is a fascinating quirk of the diurnal cycle then, in the case of Melbourne.
So it seems that at the 3 country places quoted by Weatherzone,
the period post 9am on the 11th was NOT cooler than the min for the night 11/12th which runs to 9am on 12th. I will try and dig the data out.
Remember though that the BoM map is for the minimum anomaly, not the hottest night anomaly. Not always the same thing. And surely the central issue here is the Feb 1902 min of 30.6 – how exactly does that compare with Melbourne in the 24hr period for the 12th Jan 2010.
‘Remember though that the BoM map is for the minimum anomaly, not the hottest night anomaly. Not always the same thing.’
And therein, I think, lies the problem. Did they have ‘hottest night anomalies’ in 1902, etc?
I’m confused. I think the minimum in Melbourne was the same as way back in 1913 (or whatever it was), making it an equal record warm minimum. Now of course if Melbourne was the rural idyll it was in 1913, then the same weather conditions would have produced a lower minimum. But that is not the point – the point is that if you happened to be there a few days ago, the minimum temp was bloody hot.
Warwick, any comments on the Mildura High of 1906 considering this report…
ams.confex.com/ams/pdfpapers/155748.pdf
Any documentary evidence that Mildura PO had a Stevenson Screen in 1906?
Cheers
Marc
Thanks for that pdf report MarcH which I had not seen. If you go to comment 7 at my article “Australian mean annual temperature reconstruction 1882-2009” you will see several circa 1900 press articles searched through the NLA which report the use of the Stevenson screen before the BoM was formed in 2008. There is also my 1995 published paper with quotes from pre 1900 Intercolonial Conferences where I think it is obvious the Stevenson screen was no novelty.
Will say more tomorrow.
I did a similar search of the NLA database and found quite a few mentions prior to 1890. The earliest being 1887 (newspapers.nla.gov.au/ndp/del/article/3462243).
Brian Bradshaw’s piece on Instruments and observing networks in “Windows on Meteorology: Australian perspective” (Edited by Eric K Webb (ISBN0643060383)) is of interest as it includes some nice early photos showing a range of instrument houses including one on page 131 of a Stevenson Screen, Octagon house and Greenwich stand in Adelaide Observatory. It also indicates that Stevenson Screens were “the type most commonly used to house thermometers” p 130.
A search of photos of the Mildura Post Office prior to 1906 at the local Historical Society may bear fruit. If the screen was in fact a Louvered version then the contention that the readings are widely erroneous seems less justified. The BOM indicate that the “official” Steven Screen was installed at Mildura in July 1906.
There are a number of 1939 records (not official) of 120 F, including one from Eldorado.(See newspapers.nla.gov.au/ndp/del/article/12085740) Apparently this station was used for rainfall but somehow not “offically” for temperature. I don’t suppose you know if there was a Stevenson Screen here?
In a post dated 7Jan10 about the article “BoM hottest decade” I wondered if adjustment of temperature coincided with the introduction of electronic measurement and recording where it is easy to put in a correction factor. Tbe abstract below from an recent article by Menne et al (see pielkeclimatesci.wordpress.com/)which attempts to “jump the gun” on Anthony Watts data about poorly sited weather stations mentions electronic sensor changes. The question remains has a bias been put into instruments and applied incorrectly ie increased temperatures rather than reducing temperatures where heat island effects apply. Any sudden jump (or drop) is a sign of a correction factor being employed and this needs to be justified.
“Recent photographic documentation of poor siting conditions at stations in the U.S. Historical Climatology Network (USHCN) has led to questions regarding the reliability of surface temperature trends over the conterminous U.S. (CONUS). To evaluate the potential impact of poor siting/instrument exposure on CONUS temperatures, trends derived from poor and well-sited USHCN stations were compared. Results indicate that there is a mean bias associated with poor exposure sites relative to good exposure sites; however, this bias is consistent with previously documented changes associated with the widespread conversion to electronic sensors in the USHCN during the last 25 years. Moreover, the sign of the bias is counterintuitive to photographic documentation of poor exposure because associated instrument changes have led to an artificial negative (“cool”) bias in maximum temperatures and only a slight positive (“warm”) bias in minimum temperatures. These results underscore the need to consider all changes in observation practice when determining the impacts of siting irregularities.
Further, the influence of non-standard siting on temperature trends can only be quantified through an analysis of the data. Adjustments applied to USHCN Version 2 data largely account for the impact of instrument and siting changes, although a small overall residual negative (“cool”) bias appears to remain in the adjusted maximum temperature series. Nevertheless, the
adjusted USHCN temperatures are extremely well aligned with recent measurements from instruments whose exposure characteristics meet the highest standards for climate monitoring. In summary, we find no evidence that the CONUS temperature trends are inflated due to poor station siting.”
It seems that the above paper used less than half the data collected by Anthony Watts and was not properly peer reviewed. The AGW clique are trying to protect their turf.
Without blowing my trumpet Peterb, can I just say that working with Australian data, it is seldom that data quality allows the sort of conclusions you are reviewing from Menne at al. My recent examination of Canberra Airport by comparing with Tuggeranong, was only possible because of the fluke circumstances that the Tuggeranong existed only 15km away from AP and the 1997-2009 period had no missing months in both sites.
Warwick, With due respect (I appreciate your many years of effort to get the truth on AGW claims), in my Jan 6 post I indicated that at Gayndah there was an overlap period (probably not long enough) between the PO site (which had been operating since 1870) and the new airport site (2.5 km away). The airport was recording 0.2C lower in both min and max. temps. I also noted at the PO site that around 1975 there was a 0.5C jump in min and max temps. I wondered why. Was this a sudden heat island affect from say sealing the roads or having an airconditioning unit close by, or was there a change in instrumentation with a deliberate bias (or wrongly applied bias)?
I would have thought that Gayndah was much more representative of South East Queensland conditions than Brisbane airport. If you adjust the recent Gayndah PO temperatures down by 0.5C then there would have been no temperature increase in over 100 years.
Peterb, the jump around 1975 may well be the “Great Pacific Climate Shift” which does reveal itself through Australian T data. See comment 2 at my link. I will try and drag up some Gayndah history. Where are you getting data from 1870 ? I can only see T data from 1894, but it may have read just rainfall for earlier years.
Sorry, my reply should have been here
Thanks Warwick,
It is possible that the PDO was responsible but around 1975 was also the time of reduction in the number of sites used by GISS and CRU for computer model’s calculation global average temperatures. If PDO was a cause should not the temperatures have gone down by the same amount as the sudden jump?
Kerr’s paper makes reference to Trenberth who is caught up in the Climategate emails and files showing data manipulation. I think Trenberth’s Global Energy Budget (Kehl&Trenberth 1997 and Trenberth et al 2009) is very biased towards AGW. In the latter, Trenberth has references to the infamous Jones and Hansen. I think the radiation balance by A Maurellis (Physics World May 2003 physics.world.com/cws/article/print/17402) makes much more sense.
Using an equation (from Prof Hotel at MIT) to determine overall absorptivity of CO2 in the atmosphere involving partial pressures, temperatures, beam length and the wavelength absorptivity spectrum I calculate that CO2 makes a negligible contribution to incoming or outgoing radiation fluxes.
regards
Warwick, have you seen this for data manipulation by GISS www.rockyhigh66.org/stuff/USHCN_revisions_wisconsin.htm
A neat set of animations. Most seem to look warmer in 2010, a few are not – would be preferable to see the trend numbers, eg. running linest in Excel.
This made me dig up an old post of mine from four years ago, which is suddenly topical in view of recent revelations. In that I featured a 2001 email from Jim Hansen.
Over to you readers.
I’ve been looking at some of the “non-BOM” data from a nearby agricultural research station (Medina W.A.), plotting values for temperature, insolation and wind from 1995 to 2009. No significant climate change around here.
NB There is a month of no-data in the period: May 1995
What’s interesting is that peak temperatures seem to lag peak insolation by about 1 to 2 months. Similarly for wind speeds; though not as clearly. Maybe there’s a data-collection artifact.
Plotting mean avg temperature against insolation directly produces a relatively poor correlation. R^2=0.47 on an exponential fit. Plotting the temperature 2 months later than the insolation increases R^2 to 0.72. Plotting the temperatures 1 month after insolation produces an R^2 of 0.80, an even better correlation.
I’d have to look at the daily figures to find the “sweet spot” for optimum correlation, indicating a more precise latency due to thermal capacity. But for now, one month looks pretty close.
OOPS … almost forgot.. There are a number of ag stations, including one in South Perth. Data are limited … some have data from only 2005 onwards.
I live in Warrnambool Vic and regularly check our local weather details on weatherzone. Something strange has happened on a few occasions lately. The stated daily maximum temps do not correlate with the half hourly data. For instance Sunday Feb 4 the highest maximum recorded for the day was 30.6 deg but the official maximum for that day is 32 deg. Am I missing something? Are the maximum temperatures spikes between the half hourly readings? Or is there something sinister going on?
Yes Stephen, I have assumed that cases such as you point out for WARRNAMBOOL AIRPORT mean that there was a higher peak between the half hour pips. But take a look at your neighbour Mortlake, the BoM half hour series here shows a max of 33.9 at 5pm on the 7th, yet the max for the day was only 33. So maybe there are two series in some cases. My experience tells me that asking the BoM seldom solves an issue. It is good people are watching. Here is an interesting case where a reader wrote to the BoM multiple times over many months about rainfall numbers in the ACT. You would think we were a Third World country.