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Paradox said..FormulaNova said..Harrow said..
Ever wonder why all the statistics that get shown start at 1910 and not 1900? It's because if they showed the data from 1900-1910, you might come to the conclusion that the country is cooling down.
Harrow, do you know this to be true or are you making this up? Do you have data for the years before 1910?
Edit: It sounds like you are making this up.
www.bom.gov.au/climate/data/acorn-sat/#tabs=FAQs"The second limitation is that many of these early observations were taken using a variety of observing methods. The Australian Bureau of Meteorology was formed in 1908 by an Act of the Federal Parliament. The formation of a national meteorological agency soon addressed the lack of national standards for instruments and calibrations, as well as limitations on the continental coverage of observations.
The standardisation of instruments in many parts of the country had occurred by 1910, two years after the Bureau was formed. Standard observational practices (such as the use of a
Stevenson screen to house the instruments) were in place at most sites in Queensland and South Australia by the mid-1890s, but in New South Wales and Victoria many sites were not standardised until between 1906 and 1908."
You would think from that comment that everything before 1910 was done by drunkards with a thermometer on the brick wall. This is far from the truth and there were plenty of official sites that operated prior to 1910 in exactly the same manner with Stevenson screens.
While I am sure they have to draw the line somewhere it does create perception issues with 1910 coinciding with the end of the Centenary drought and the high temperatures experienced in the late 1800's and and early 1900's that go came with it. A look at any global temperature record will show 1910 as the low point and it was hotter prior. Also plenty of Australian records to show that as well.
www.abc.net.au/news/rural/2019-07-16/federation-drought-analysis-finds-huge-ecosystem-losses/11312694?fbclid=IwAR1FevrnoEmMyozxoM1A1U0VthNmkKGmMBnHQpDQzMYkUnijnE1qqw3KsbI I don't think anyone disagrees the earth has warmed over the last 50 years, including Australia. Fortunately the increased temperature has also increased rain overall.
But if the BoM was trying to manipulate data to stoke climate change fears by only choosing temperature records since 1908, why do they use rainfall records from 1900?
The BoM is upfront about why it doesn't use temperature recordings from the era of the Federation drought - at that time many thermometers used to record readings lacked "Stevenson Screens" and were therefore exposed to the elements and recorded higher temps. Here is a classic example of why the BoM is acting perfectly reasonably when they ignore the older un-screened readings; a 1907 report from a Mildura paper that showed the installation of a Stevenson Screen dropped the recorded temp by up to SEVEN DEGREES compared to nearby stations without the screens;
trove.nla.gov.au/newspaper/article/196159366?searchTerm=%22thermometer%20screen%22&searchLimits=There is no doubt that the lack of Stevenson Screens is a problem with earlier measurements; the famous meteorological pioneer Clement Wragge noted that their uniform use was "of the very highest importance" as early as 1886 and insisted they be fitted in Tasmanian weather stations, for example, before he used their data. Otherwise, he said later, recordings could be "seriously misleading", which is pretty obvious. So when the BoM kicked off, they started standardising screens and weather stations;
trove.nla.gov.au/newspaper/article/205008054?searchTerm=meteorology%20thermometer%20screen&searchLimits=sortby . The BoM has been aware of the problem of pre-1908 data as early as - 1908! See
trove.nla.gov.au/newspaper/article/14951707?searchTerm=meteorology%20thermometer%20screen&searchLimits=sortbyAfter about 1910, the screens were in normal use and therefore recorded temps dropped in many places. See, for example,
trove.nla.gov.au/newspaper/article/148557564?searchTerm=%22thermometer%20screen%22&searchLimits=This piece claims, though, that as late as the 1960s, Adelaide's temperature records were affected by poor thermometer siting, which made the city look degrees hotter than it really was;
trove.nla.gov.au/newspaper/article/133925238?searchTerm=meteorology%20thermometer%20screen&searchLimits=sortby|||l-decade=196
One interesting point is that at least two towns complained that the old records made it look as if their towns were hotter than they actually were, therefore scaring people away.
So, to summarise;
1- there were many problems with old temperature records;
2- the BoM knew of this as early as 1908;
therefore it's utterly wrong for anyone to imply that the BoM is trying to talk up the problem with pre-1908 data in order to manipulate weather records to make it look as if the climate is warming. The problem with pre-1908 data has been acknowledged for over 100 years!
beefarmer
> 9 months ago, 11 Jan 2020
