Laugh till you cry wrote on Feb 10^th, 2016 at 6:38pm:



Yeah. BoM homogenises data. We get that. According to the report into BoM they can't replicate their homogenisations. It is not a mathematical algorithm, it is a judgement call.

"I think that place should be 2.5 degrees warmer." "There done . Fixed." But it is World's Best Practice according to BoM. So that means US and UK as well use that method.

link, cheers

'The ACORN-SAT data uses a more limited and fixed network of temporally homogenised data that is specific for estimating change over time, and particularly climate change. Temporal homogenisation refers to analyses that attempts to account for spurious (non-climate related) changes in the data.'

http://www.bom.gov.au/climate/current/events/january-heatwave-methods.shtml

'The Forum noted that the extent to which the development of the ACORN-SAT dataset from the raw data could be automated was likely to be limited, and that the process might better be described as a supervised process in which the roles of metadata and other information required some level of expertise and operator intervention. The Forum investigated the nature of the operator intervention required and the bases on which such decisions are made and concluded that very detailed instructions from the Bureau are likely to be necessary for an end-user who wishes to reproduce the ACORN-SAT findings. Some such details are provided in Centre for Australian Weather and Climate Research (CAWCR) technical reports (e.g. use of 40 best-correlated sites for adjustments, thresholds for adjustment, and so on); however, the Forum concluded that it is likely to remain the case that several choices within the adjustment process remain a matter of expert judgment and appropriate disciplinary knowledge.'

http://www.bom.gov.au/climate/change/acorn-sat/documents/2015_TAF_report.pdf

We're having a heat wave, a tropical heat wave...