IMHO the BoM in Perth is gung-ho when it comes to claiming any records to do with warming. So I have taken a few hours to compare this summer to March heatwaves with those from 1977/78 – in each case comparing the Perth station with, sites at Perth Airport, Pearce RAAF, York and Merredin.
Taking the BoM definition of a Perth heatwave as 3 days over 35C.
I assembled daily max T for the months Dec to Mar incl for 1977/78 and 2011/12 – for the above sites. Note in 1977/78 Perth data was recorded at “9034 Perth Regional Office”, York was “10144 York Post Office” – the others were “9021 Perth Airport”, “9053 Pearce RAAF” and “10092 Merredin”.
In 2001/12 Perth data was recorded at “9225 Perth Metro”, Perth airport, Pearce and Merredin were unchanged and York was at “10311 York”.
I condensed my data down to only those days included in the “official” Perth heatwaves for the two periods and there are 27 Perth heatwaves days in both 1977/78 and 2011/12 Dec to 11 March so far – note Pearce RAAF had missed readings on days in 1977/78 and Merredin had 2 missing. In 2011/12 Pearce had 1 missing day.
Next I averaged the temperatures for these various places for the 27 day period of the Perth heatwaves.
Note in the ABC article linked above; how the BoM make big of the fact that in 2011/12 Perth has 8 heatwaves while only 7 were recorded in 1977/78.
In fact in 1977/78 there were only four 3 day events but there were two 4 day events and a seven day event.
While in 2011/12 so far we have had six 3 day events and one each of 4 and 5 days. So heatwaves tended to be longer in 1977/78 – a point the BoM did not tell the pliant ABC.
The other interesting point that emerged was that while Perth Regional Office was slightly cooler in 1977/78 than Perth Metro was in 2011/12. All the other sites were warmer in 1977/78 compared to 2011/12.
This supports my contention that the BoM is not correct in assuming that Perth Metro is equivalent to Perth Regional Office. The BoM is also not correct in always ignoring the fact that Perth has a growing urban heat island (UHI).
The BoM should take far more care reporting pro-IPCC conclusions hastily drawn from their imperfect data.
No mention of the unusually cool summer in nearby Meekatharra.
Just 5 x 40 degree days this year (2012)
Only 1933 , 1955 and 2000 are similar.
www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=122&p_display_type=dailyDataFile&p_startYear=2012&p_c=-17206462&p_stn_num=7045
Added by Ed: You are correct Ripper – vast areas of WA have been anomalously cool for all of summer – Dec to Feb see the huge areas of green on these maps on right hand panel.
Note the miniscule areas of actual warmth clinging to the coast compared to the much larger areas the BoM predicted warm. The BoM are shameless pro-warming, unbalanced propagandists.
Warwick thank you for this timely post
already Ch 10 is trumpeting record for Perth
I don’t know if you’ve heard about what has happened to Jennifer Mahorasy
full story here
jennifermarohasy.com/2012/03/media-watch-under-scrutiny-2/comment-page-1/#comment-499961
copy of my comment on Catallaxy catallaxyfiles.com/2012/03/12/watchdog-can-muzzle-government-critics/#comments
Added by Ed: It was pleasing indeed to see how the return broadsides by JM destroyed the Mediawatch case.
What a bunch of biased Govt paid meddlers Mediawatch are.
I also notice that Perth Airport only had 7 heatwaves over the same period. Perth Metro records show a heatwave from 8th – 10th Feb whereas Perth Airport records 34.8C on the 8th so making a two-day +35C, not 3.
Perth Metro has been only operational since 1994 so using this one station to compare with a long-running station such as Perth Airport is not quite kosher.
Perth Airport has some 31 days of above 35C during Dec 1977 – Mar 1978 which is again different to the now-closed Regional Office. The station records 2×3 day, 1×4 day, 1×6 day, 1×7 day and 1×8 day event – only 6 heatwaves. This was because the 29th Jan was recorded at 35.2C (making a continuous heatwave from 25th Jan to 1st Feb) whereas Perth Regional recorded only 33.0C thus breaking it into 2 separate heatwaves.
Maybe a heatwave should be 3 consecutive days over 35C and then start again. You could have the situation where in one month each day could be over 35C and this would only count as one heatwave.
has this paper been peer reviewed yet?
Note by Ed: I would bet Val that the Belinda Campbell effort is in no danger of disturbing the intray of the Editor of any Learned scientific journal.
But I can be wrong.
However the BoM has decades long history of sitting on findings that disturb the tranquility of BoM mythology.
link to the above article is here and links to links
www.canadafreepress.com/index.php/article/29775
Hallelujah! Somebody with climate knowledge is seeking to set the record straight and counter the incompetence of the WA media.
Perth’s monopoly weekday press, The West Australian, started this heatwave sensation (lead story ABC TV News last night) on March 3 with a story that Perth might actually have some more hot weather in early March (amazing!), reporting at that stage that maxima need to reach 35C for five consecutive days to be considered a heatwave.
The BoM says there is no clear definition of “heatwave” but over the past week the media has been put straight with a definition that three consecutive days need to reach 35C. Debatable use of the word but if we’re talking about a “record” eight times since the Perth max hit 35C for three days since November, fair enough.
However, sorting through the muddle of media reporting, yesterday’s story in the Sunday Times about Perth’s record current heatwave (?) had a BoM spokesman saying: “The all-time record is 10 heatwaves. That was recorded in February 1975 and 1988.”
Say what? It’s hoped the BoM spokesman was referring to the two periods of 10 consecutive days in Feb 1975 and Feb 1988 with max above 35C … 35.5, 38.3, 39.6, 40.9, 39.7, 40.7, 35.5, 36.8, 36.4, 35.6 in 1975 and 35.9, 35.8, 36.5, 37.4, 37.6, 37.9, 38.1, 39, 38.9, 38.8 in 1988.
What the BoM and media aren’t into reporting are irrelevant things such as the fact that last February the mean max at Perth Metro was 34.2C and this February it was 31.1C – which is .4C below the long-term Feb mean max of 31.5C (1961-1990 baseline mean). The mean monthly max for February 1975 was 34C and in 1988 it was 33.9C.
Where’s that headline? “Perth enjoys below average February”
Instead we have headlines such as “Endless Summer” a couple of weeks ago in the Sunday Times wherein the BoM declared Perth’s summer average max at 31.8C, “slightly less than the record 32C summer averages of 2010-11, 2009-10 and 1977-78.”
December 2011 – 30.5C, January 2012 – 33.5, February 2012 – 31.1 / Average = 31.7C, not 31.8C. Never let the facts get in the way of a good climate change.
Mind you and as Warwick points out, Perth temperatures before 1994 were recorded several kilometres south in the central city close to the Swan River, and before 1967 they were recorded atop Mt Eliza (see www.waclimate.net/perth-temperature-history.html), so when referencing the 9225 Mt Lawley site, Perth’s temperature history only really begins in 1994.
It has been hot at Perth Metro since 2008 (see the 2009 BoM bug – www.waclimate.net/bom-bug-temperatures.html) and we’ve had well above average days over 35C, but a Jan-Feb-Dec annual look at the number of 35+ days during past years shows the record still stands in 1979:
Mt Eliza
1898 15
1899 14
1900 13
1901 15
1902 10
1903 1
1904 17
1905 13
1906 7
1907 8
1908 11
1909 12
1910 18
1911 6
1912 6
1913 13
1914 12
1915 13
1916 16
1917 8
1918 9
1919 13
1920 9
1921 21
1922 24
1923 8
1924 9
1925 9
1926 3
1927 16
1928 14
1929 5
1930 16
1931 13
1932 23
1933 11
1934 20
1935 16
1936 11
1937 5
1938 8
1939 9
1940 8
1941 16
1942 12
1943 12
1944 3
1945 14
1946 16
1947 4
1948 9
1949 7
1950 10
1951 15
1952 8
1953 15
1954 8
1955 14
1956 17
1957 13
1958 13
1959 15
1960 12
1961 8
1962 23
1963 27
1964 16
1965 10
1966 22
Wellington St
1967 13
1968 15
1969 15
1970 10
1971 17
1972 11
1973 28
1974 12
1975 24
1976 25
1977 20
1978 20
1979 30
1980 18
1981 13
1982 10
1983 14
1984 11
1985 16
1986 20
1987 17
1988 10
1989 20
1990 18
1991 13
1992 19
1993 16
Mt Lawley
1994 15
1995 16
1996 19
1997 21
1998 16
1999 25
2000 19
2001 5
2002 19
2003 16
2004 21
2005 9
2006 17
2007 13
2008 25
2009 28
2010 23
2011 29
Thanks to the media, most West Australians think we’ve just suffered through a scorching year as climate change encroaches. That’s possibly because no story yet published has informed them that across WA, the mean annual temp in 2011 was .1C below the historic normal.
It was a below average year across WA, but not in the very warm parallel universe of the BoM and a clueless media.
My physics tells me that it’s not the temperature at one single point on the map that counts but the total energy measured all over the country, and if one considers this, Australia is caught in deep freeze.
here’s the Oz
www.theaustralian.com.au/news/breaking-news/perth-sweltering-in-four-day-heatwave/story-fn3dxity-1226297493182
PERTH is sweltering through a record-breaking eighth heatwave.
The Bureau of Meteorology defines a heatwave as three consecutive days at or above 35C.
The record was reached during the weekend and today the temperature remained high, peaking at 40.6C.
Maximum temperatures for the previous three days were 38.9C on Friday, 39.5C on Saturday and 41.4C yesterday.
It is the third time that Perth has recorded four consecutive days above 38C in March, the bureau says.
The other occasions were between March 12-15, 1922 and March 7-10, 2003.
Only once before has Perth previously recorded two heatwaves in March and that was in 1988.
The bureau says the previous record of seven heatwaves in the summer/autumn season happened in 1977/78.
.
. .
Perth has also experienced its hottest start to March on record.
The mean daily maximum temperature for March 1-12, 2012 was 35.9C, breaking the previous record of 34.7C in 1979, the bureau says.
Temperatures are expected to drop down to 30C by tomorrow and hover around that temperature for the rest of the week.
The media isn’t clusless Chris, it is complicit.
RAAF Pearce would have been missing most weekends in 1977/78. I was a meteorologist on base in 1972-1975 and AFAIK things didn’t change until a fair bit later. We used to work Monday to Friday except for the very odd occasion.