Wednesday, January 15, 2014

Fact checking the weather man

Graham Creed ABC's weather man, runs a blog. We fact checked the statistics is his post of the 14/1/2014, seems he is a little selective with his cherry's:

CANBERRA
Graham says:
Canberra, In 2009 there were 3 days of consecutive 40 degree temperatures. This is pretty significant given there have only been 11 days above 40 in Canberra’s history. Seven of those has occurred in the last 5 years. The 1979 heat wave was significant because it had five consecutive days in excess of 37 degrees. Hottest day on record is 42.2 and was recorded back in 1968. Data courtesy ABC Canberra and BOM.

Independent analysis indicates that Graham seems to have forgotten the catastrophic heatwave of January 1939, this had a run of 9 days over 38 degrees including 5 days over 40. It also includes Canberra's record temp of 42.4 degrees C. The devastating Black Friday bushfires affected much of SE Australia. The Canberra Times reported the following temperatures in Fahrenheit (celcius) as recorded at the Acton meteorological station:
Wednesday 11/1/1939: 108.4 (42.4)* seems this should be the record beating GC's mention by 0.2

In terms of the number of days over 40, we make it least: 18 comprising:
5 for the 1939 heatwave outside BOM records as recorded at the Acton meteorological station, 
7 from BOM station records for Canberra Station ID 70014*
5 readings from BOM station records for Canberra Station ID 70351**
1 in 1932 104.2 (40.1) recorded 28/1/1932-outside BOM records as recorded at the Acton meteorological station,, 

Number of days 40 and above in the last 5 years: Last 5 years 2014-5=since 2009=5

*7 readings 40 and over at 70014: 41.4 recorded 31/1/1968, 42.2 recorded 1/2/1968-BOM, 40.5 recorded 12/1/2007, 40.2 recorded 3/1/1973, 40.0 recorded 18/1/1998, 40.0 recorded 7/2/2007, 40.0 recorded 8/2/2008
**5 readings 40.3 recorded 6-8/2/2009 (3 days), 40.1 om 5/1/2013, 42.0 on 18/1/2013
UPDATE: It seems the Acton meteorological station is closed BOM station 70099 for which daily observations are not available online. We have asked BOM why this is the case. Of interest the highest monthly mean for January remains Jan 1932 @ 32.5 degrees for station 70099. The record at Canberra Airport (70351) is 32.3 in January 2013.

ADELAIDE
Graham says: Adelaide: 2009, 13 consecutive days over 33, 6 consecutive days above 40 and 4 consecutive days over 23.

Graham forgets the 1908 and 1939 heatwaves. 
1908 Monthly mean record @ 34.2 degrees with 10 days over 40 (4 consecutive days-Jan 4 to 7 and 6 consecutive days 14-19)
1939 Monthly Mean @ 33.6 degrees with 5 days over 4 and Adelaide's record maximum of 46.1 degrees.

MELBOURNE
Graham says: Melbourne: 2009 12 consecutive days above 28, 5 consecutive days above 30 3 consecutive days above 43.

Once again it seems 1908 was hotter
The January 1908 heatwave in Melbourne helped push the January monthly mean to its as yet unsurpassed maximum of 31.0 degrees. The month included 15 days over 30 and a run of 5 days over 40.

UPDATE: Seems ABC's weather man has made some changes following our inquiries:

Graham Creed's blog post was based on Bureau of Meteorology Climate Information and was taken from a Bureau interview on ABC Radio in Canberra. The figures were attributed to the Bureau.  The Bureau's figures and Graham's blog post were based on the climate record from Canberra Airport. The Bureau appears not to have any records of temperatures at Acton which were the basis of the Canberra Times article. They are therefore unverified weather records and we would not normally use them. The blog has been modified to clarify that the data refers to the record at Canberra Airport.

The reference to the 2009 heat event was just meant to be a comparison with a recent heatwave. It did not claim those figures were a record. It would have been more accurate to say that "This is pretty significant given there have only been 11 days above 40 since the Bureau began recording more than 70 years ago."

Accordingly, while noting your concerns, Audience and Consumer Affairs are satisfied that reasonable efforts were made to ensure the accuracy of the article and it was in keeping with the ABC’s editorial standards. Nonetheless, please be assured that your comments have been noted and conveyed to ABC News management.

The post now reads as follows, but still ignores 1939:
Canberra Airport, In 2009 there were 3 days of consecutive 40 degree temperatures. This is pretty significant given there have only been 11 days above 40 in Canberra Airport’s history. Seven of those has occurred in the last 5 years. The 1979  heat wave was significant because it had five consecutive days in excess of 37 degrees. Hottest day on record is 42.2 and was recorded back in 1968. Data courtesy ABC Canberra and BOM.







9 comments:

  1. In the Australian newspaper a few days ago on the weather page for Melbourne, the highest temp ever recorded on that day was over 44 degrees and occurred in 1861 while the lowest ever recorded on that day was around 7 degrees in 1868. Canberra as we all know is part of a different universe to the rest of Australia.

    ReplyDelete
  2. Thanks for that, yes Canberra a different universe, one where the official weather records start in March of 1939!
    Note there are some issues with non standard instruments used prior to the introduction of the Stevenson Screen. These tend to run a little higher so some adjustments made to early records justified when comparing to SS measurements.
    Stevenson screen introduced gradually at Australian sites from the late 1880s. See the following for some interesting history...http://www.warwickhughes.com/papers/ozstev.htm

    cheers
    M

    ReplyDelete
  3. Just followed you link to January 1908, got the following message.

    Page header, Weather Data temporarily unavailable.

    "Improper use of this application. Please go back to Climate Data Online historical weather data"

    Could it have disappeared for adjusting?

    ReplyDelete
    Replies
    1. looks like the link has done something odd. try...
      http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=136&p_display_type=dailyDataFile&p_startYear=1908&p_c=-1481640279&p_stn_num=086071

      or try searching from the climate data page under Melbourne regional office-station ID 86071
      http://www.bom.gov.au/climate/data/index.shtml

      Delete
  4. BOM also lied and the ABC happily passed on the lie unchecked stating there was no standard definition of a heat wave. So Now BOM Changes Definition of Heat Wave to suit their Global Warming Story!

    The definition recommended by the World Meteorological Organization is when the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5 °C (9 °F), the normal period being 1961–1990. http://en.wikipedia.org/wiki/Heat_wave

    BOM has decided to announce a new definition of 'heatwave' for Australia, claiming that there is no standard definition of heatwave. Australia is of course one of the world's warmest countries so BOM will obviously ensure they can 'officially' use the term 'heatwave' more often. This is the BOM revised definition:

    "A heatwave is now defined by three or more days of unusually high maximum and minimum temperatures in any area."They have chosen three grades severe, extreme and most serious. So apparently there is no typical or standard heatwave according to BOM.

    In the video clip here http://www.abc.net.au/news/2014-01-14/bureau-of-meteorology-provides-national-heatwave-definition/5199712 when the new BOM system is explained it is claimed that there has never been a formal definition of a heat wave, which of course is patently untrue. Now BOM have a non specifically defined heatwave definition down to just three day periods, there is absolutely no doubt that we are going to be swamped with heat wave warnings around the country which would previously have represented NORMAL summer weather.

    This will further their strategy to try to convince the population that we are experiencing more extreme weather conditions due to man made climate change.

    ReplyDelete
    Replies
    1. Good point. My guess is that we wil now see heatwave warnings announced for the occasional warm period in winter.

      Delete
  5. Thanks for this Marc - I have commented on the failure of the BoM prediction of 4 days over 40 for Canberra.

    Another warmist prediction bites the dust - Canberra four days over 40° fails in 2014 but 1939 heatwave was hotter and longer
    http://www.warwickhughes.com/blog/?p=2652

    ReplyDelete
  6. It has now gotten to the point that the weathermen are blatantly changing the temperatures so the year end totals will not show what WE ALL KNOW; the world is COOLING and not warming.

    But hey, so what we shaved a temperature or two, or three off each day, every day of the year.

    ReplyDelete
  7. The adelaide maximum has been reduced from 117.7 f or 47.6C to 46.1C the Bom are warmists publishing false data . They should at least publish the raw data next to their adjusted downwards figures

    ReplyDelete

Please keep to the topic. Abusive comments and bad language are simply not tolerated. Note that your comment may take a little while to appear.

Note: Only a member of this blog may post a comment.