From Jennifer Marohasy’s Weblog
By Jennifer Marohasy
John William Abbot versus Director of Meteorology was to be heard within the Administrative Appeals Tribunal, Brisbane, yesterday, Friday third February 2023 – a spotlight of this collection of weblog posts. Whereas it was to be a public listening to, and I used to be to be the skilled witness, earlier than I might current my proof, the case was taken again into mediation and the general public requested to go away.
I’m now part of the mediation that was not resolved yesterday. I’m now legally certain to not touch upon this ongoing mediation. That’s set all the way down to resume on Tuesday.
I’m very grateful to Caroline, Gideon, Charles and Howard, for attending the general public listening to yesterday – albeit so transient.
This sage has been ongoing for me in some kind since twenty fifth August 2015 once I first requested parallel information for Wilsons Promontory Lighthouse from the digital climate station counting on platinum resistance probes since September 2000 and as a test from the unique liquid-in-glass thermometers (together with the mercury), which had been put in again in 1872 and theoretically nonetheless recording temperatures. I particularly requested:
Might you please additionally present me with the entire temperature document (most and minimal) as measured from every of those totally different thermometers for the interval of their accessible document.
I’m notably eager to know if there’s a single steady month-to-month document for the mercury thermometer put in in 1872, to the current. [end]
This requested was made via the climatedata@bom.gov.au portal, and I adopted up with telephone calls, however my utility was by no means formally acknowledged. We do understand it was mentioned by Bureau workers as it’s talked about in correspondence that was made public following {a partially} profitable FOI request by Mulholland (#FOI30-6142) regarding limits set on how chilly temperatures could be recorded at Goulburn. The correspondence is accessible on-line right here.
As a result of a change in measuring tools can probably create discontinuities in a temperature document, it’s Australian Bureau of Meteorology coverage to have new tools recording side-by-side with outdated tools for a interval of a minimum of 2 years. On this approach, readings from the brand new tools could be in contrast with readings from the outdated tools, together with to test they’re comparable – that there are not any discontinuities. That is the parallel information.
It’s cheap to imagine this information can be pubic, however it’s guarded by the Bureau and stored secret. The Bureau additionally declare it’s undigitized and solely probably accessible as laborious copies of A8Forms and that the Bureau lacks the accessible assets for scanning to supply this on request. Entry to this information for the Brisbane airport climate station was the target of an FOI request by John Abbot and so started the present saga.
In 2017, I used to be profitable in buying some parallel information for Mildura. After many late nights manually transcribing values from the scanned A8 Kinds supplied to me following the intervention of then Minister for Power and Atmosphere Josh Frydenberg I charted the information and did some evaluation.
This evaluation confirmed that the primary probe, which turned the official instrument at Mildura on 1 November 1996, was recording too cool relative to the mercury with some seasonal variability. On 3 Might 2000, the Bureau modified the Stevenson display to a smaller design, and whereas there is no such thing as a document of a change in the kind of probe, this virtually actually additionally occurred based mostly on the very totally different recording sample relative to the mercury, see Chart 1.
Initially the temperatures as recorded at Mildura, from 3 Might 2000 from what I’m assuming was a brand new second probe within the new shelter, had been extra according to the measurements from the mercury thermometer. However then I might see from the information that the temperatures from the probe began to chill relative to the mercury thermometer for the interval to 27 June 2012. Cooling was at a price of almost 1°C per 100 years.
Then on 27 June 2012 the probe which had been recording the official temperature at Mildura for 12 years whereas drifting to document ever cooler, was modified. The restricted accessible parallel information signifies that this third probe information too sizzling relative to the identical mercury thermometer – usually by 0.4 °C.
That is the extent of the accessible parallel information, and it suggests:
1. The change from a mercury thermometer to a probe makes a fabric distinction to the reliability of the historic information.
2. This issues for understanding local weather variability and alter – the development.
3. This data is within the public curiosity – given far reaching public coverage selections are being made on the idea of a 1.5C tipping level.
4. We all know the information exists as a result of I acquired the scanned A8 Kinds for Mildura with recordings from each probes and the mercury again in 2017. We additionally know the information exists based on the Bureau’s personal referencing of this information and dialogue of this information.
On twelfth December 2019, John Abbot made a request to entry the parallel each day most and minimal temperature datasets for the Brisbane airport climate station; that’s the measurements recorded utilizing the mercury thermometer as a possible test on the measurements from the platinum resistance probe.
That information has by no means been supplied and is the origin of the present saga to be resumed on Tuesday via non-public mediation.
