Monday, 20 December 2010, 9:47 am Press Release: New Zealand Climate Science Coalition

Call on NIWA to admit latest temperature review not valid

A call has been made on the National Institute of Water and Atmospheric Research (NIWA) to admit that that there is no valid statistical justification for its claims of a 0.91 degree C rise in New Zealand’s average temperature last century. The call comes from Bryan Leyland, a spokesman for the New Zealand Climate Science Coalition (NZCSC), following the release this week by NIWA of its revised Seven Station Series (7SS), which the agency claimed has been vindicated in a peer review by the Australian Bureau of Meteorology (BoM).

Enlarged here.

Mr Leyland has also called on the Minister of Science and Technology, Hon Dr Wayne Mapp to ask for the resignation of John Morgan as chairman of NIWA. “Mr Morgan has misled New Zealanders about the robustness of the latest 7SS review. In his media release this week, Mr Morgan wrote that NIWA had asked the Australian Bureau of Meteorology to conduct the peer review to ‘ensure a thorough examination by an independent, internationally respected, climate science organisation. Mr Morgan confirmed that the scientists from the Bureau’s National Climate Centre concluded that the results and underlying methodology used by NIWA were sound.’”

Mr Leyland said Mr Morgan’s interpretation was at odds with what the BoM had actually said in its peer review: “The review does not constitute a reanalysis of the New Zealand ‘seven station’ temperature record. Such a reanalysis would be required to independently determine the sensitivity of, for example, New Zealand temperature trends to the choice of the underlying network, or the analysis methodology. Such a task would require full access to the raw and modified temperature data and metadata, and would be a major scientific undertaking. As such, the review will constrain itself to comment on the appropriateness of the methods used to undertake the ‘seven station’ temperature analysis, in accordance with the level of the information supplied.”

Mr Leyland said that when in December 2009, NZCSC issued a formal request for the schedule of adjustments under the Official Information Act 1982, specifically seeking copies of “the original worksheets and/or computer records used for the calculations”. NIWA responded on 29 January 2010, that they no longer held any internal records, and merely referred to the scientific literature. We leave it to the public to judge whether NIWA’s admission that it had lost the original raw data was a convenient let-out or a failure to maintain proper records.

“Mr Morgan’s press release also claimed that BoM’s review ensured “the ideas, methods, and conclusions stood up in terms of scientific accuracy, logic, and consistency”. This bears no relation to the extremely limited comment actually made by BoM.”

Mr Leyland said Mr Morgan’s spin on what the BoM said in its peer review was another in a long line of misleading claims by NIWA in response to a request by the Climate Science Coalition in February this year that the original 7SS was faulty and should be removed from the NIWA website.

“Either Mr Morgan was misinformed by his own NIWA officials and is not sufficiently scientifically literate to know he was being so misinformed, or he has deliberately misquoted what BoM has said. Either way, he is not a fit and proper person to chair NIWA, and the Minister should demand his resignation,” said Mr Leyland.

“Another question the Minister needs to ask NIWA is why, in view of the BoM’s reference to analysis methodology, the 7SS reassessment was not peer reviewed by someone appropriately qualified in the science of statistical analysis, given that this latest 7SS, like its predecessor, now hurriedly removed from the NIWA website, is more of a statistical challenge of balancing a range of temperatures from seven widely separated weather stations across the country, and trying to arrive at an accurate and meaningful national average temperature, a figure that many climate and statistics scientists around the world say is not possible.

Mr Leyland suggests that NIWA’s claim of vindication is premature, given that the complete 7SS review process is still a work in progress. “In answer to a question in Parliament, the Minister, Dr Mapp, said: ‘NIWA’s review of the ‘seven-station’ series will be supervised by Principal Climate Scientist Dr Brett Mullan. It will be peer reviewed internally by NIWA Chief Climate Scientist Dr David Wratt and Principal Climate Scientist Dr James Renwick; and externally by two respected non-NIWA climate scientists, who have yet to be appointed. In addition, NIWA’s intent, during the 2010/11 financial year, is to submit the work described above as a paper to a scientific journal, where it would be subject to the normal independent peer review process. This work has been incorporated into NIWA’s science planning for 2010/11.  NIWA expects the work to include calculation of the temperature trend and attaching statistical confidence intervals for the resulting “seven-station series”.

“Until that justification has been independently peer-reviewed and published, as promised, the new temperature record should be termed ‘provisional’. Also, NIWA say that they are still working on the ‘statistical confidence intervals’. All the indications are that these margins of error will be large. Until these are calculated, the provisional temperature record carries no credibility as a scientific document.

“In view of the fact that alleged warming of our country was one of the factors used to justify saddling New Zealanders with extra costs of the Emissions Trading Scheme (ETS), it is vital that any rising temperature claims by NIWA should be able to withstand a high level of rigorous scrutiny that the BoM says is not possible,” said Mr Leyland.

“We find it intriguing that NIWA now tells us that most of the claimed warming occurred in the first half of last century, whereas most of the increase in greenhouse gas (GHG) emissions did not become apparent until the second half of last century, which bears out the assertions of climate skeptics that the minimal warming that ceased about 2002 was due to natural cyclical changes, not GHG emissions and, that, therefore, there is no justification for ETS. The likely continuation of the current cooling phase will make that increasingly evident during the next couple of years,” said Mr Leyland.

He added that NZCSC will conduct its own detailed analysis of the latest NIWA 7SS as early as possible in the New Year, and that it has been promised support from climate and statistics scientists at home and overseas whose qualifications are impeccable. “If NIWA can’t get it right, we will”, Mr Leyland concluded. See release here.