Archive for February, 2011

Open Letter to Tony Burke MP

February 22, 2011

(Readers may wish to refer to previous correspondence below.)

22 February 2011

Dear Mr Burke

Thank you for the letter written by Dr Greg Ayers on your behalf, dated 10 February 2011 (Ref:  Exec 11.0009), in reply to my letter to you dated 26 October 2010.

Firstly, I am disappointed that there was no acknowledgement of, let alone apology for, either the delay in replying to my letter, or the lack of any response from the Bureau of Meteorology apart from the automated Webclim email of 09 September 2010.

The letter written on your behalf is of very poor value.  It shows little attempt to address the issues I have raised, and is composed of  redundant information (“padding”), misinformation, half-truths, evasions, contradictions  and red herrings.  There is one genuinely satisfactory response, with one pending, in the whole four pages.

Given that this is a Ministerial reply, one would have thought more care would have been taken to check the actual information I have already assembled and the specific issues I have raised, not to mention more care with basic proof-reading.

Here is my response to the letter, starting with the second paragraph:  Monitoring Australia’s climate is a high priority for the Bureau of Meteorology…

There is nothing new here, and Dr Ayers could have quoted most of this paragraph from my own posts.

Paragraph 3: When assembling these data, we take great care…

Once again, nothing new- I am quite familiar with the BOM Climate website, which I agree is quite rich with useful information.

Paragraph 4: We welcome examination and testing of our climate data and the analysis methods we use….

This is basically a paraphrasing of the automated Webclim email I received in September, and is nonsense.  Certainly a scientific paper, if and when accepted by a peer-reviewed journal, may eventually lead to a reply.  However, there are several examples of explanations of the Bureau’s procedures on the website which appear not to be published in peer-reviewed journals.  From these explanations, I have raised further queries.  A further simple explanation may have easily cleared up my queries many months ago.   Moreover, as Dr Ayers later admits, the Bureau does make “operational adjustments” which have not, as yet, had any corresponding discussion in a peer-reviewed journal.

I now offer my comments on the responses to my specific questions.  My questions are in bold, quotes from Dr Ayers are in italics.

1. What explanation is there for the large discrepancy between the 100-year trend of the homogenised data from the 100 High Quality sites, and the trend of the raw data from these and nearby sites?

Dr Ayers’ response misses the point: the difference between raw and homogenised data at the 100 High Quality sites.  Comparing the High Quality data with those from a completely different dataset may give an interesting result but is not relevant. Quoting Jones et al. is a distraction – it is a red herring.  Figure 12 in that paper refers only to temperatures from 1950 to the present, whereas the bulk of the adjustments appear to have been applied prior to this.

2. Why, if the adjustments “tend to be equally positive and negative across the network”, have the great majority of sites had adjustments that have resulted in an increased warming trend?

No useful answer given.  I am well aware of the documented homogenisation process from the cited papers.  Dr Ayers states:  “… I assure you that an evaluation of potential bias in warming trends, either positive or negative, is firmly within the compass of that work.  We will publish our findings on this matter later in the year…” This is indeed comforting- but it has only taken 15 years from Torok and Nicholls’ 1996 paper.  Why the rush?  Forgive the sarcasm, but surely any potential bias should have been evaluated before publication of the High Quality data on the Bureau’s website.

3. What explanation is there for the inclusion in the High Quality series of 15 sites previously excluded because of urban influence?

It is not clear to which 15 sites you are referring.  I cannot believe that someone with the expertise of Dr Ayers, with all the resources of the Bureau at his disposal, cannot locate this information by comparing the list of Urban stations in Torok and Nicholls (1996) with the list of 100 High Quality non-urban sites.  Alternatively, he could have checked this site, specifically Part 8: The Big Picture , where I list them.

The decision to classify a station as urban or non-urban is made on the basis of evidence for an urban warming signal and the immediate environment of the station. In Part 9: An Urban Myth, I have shown how in the Urban sites the raw data and the adjusted data both show much less warming than the non-urban sites- and despite the “evidence for an urban warming signal”, the majority of urban sites have had adjustments that increase warming.

4. Why, in a supposedly “High Quality” record, has so much low quality data been included- stations with short records (e.g. Woomera, Giles), large gaps infilled with estimates (e.g. Wilcannia, Cape Borda) or with data from sites many kilometres away (e.g. Newman), and records constructed by combining data from stations with no overlap at all (e.g. Port Hedland, Bourke, Cashmore)?

Dr Ayers’ answer is evasive- “deemed to be of high quality” indeed!  They may be “the longest and highest quality records in a particular region”, but that isn’t saying much in absolute terms.  In short, a null response.

5. Have there been any other adjustments made to the Australian temperature data apart from those documented at the BOM website?  If so, kindly supply details of all reviews and adjustments to the Australian raw temperature data including, but not limited to, Torok and Nichols, and Della-Marta et al.

The three papers described above provide details about how the high quality station data have been prepared, with the thesis by Torok providing detailed accounts of adjustments at stations… This is misinformation.  The three papers provide overviews, not details.  Torok’s thesis does not give detailed accounts of adjustments at stations.  He gives a detailed account of adjustments at Mildura and a couple of other samples, out of 224.   He shows graphs of  stations’ raw and adjusted data, and lists stations with dates and amounts of adjustments, but there are no explanations for the adjustments.

An updated summary of operational adjustments is under preparation..  So the real answer to my question is yes, other adjustments are continually being made, without, as yet, any journal article presenting arguments for them.  I look forward to the coming journal article, written after the event.

6. Can you please provide details (including dates, personnel, methods, results) of the quality control checks on the homogenisation adjustments.

The Bureau of Meteorology  relies on careful metadata checks and a number of robust statistical tests and having a large number of comparison sites available, very good metadata and a year or more of parallel observations for the same station. In theory, this will prevent any lack of quality due to “subjective decision(s) about whether and how much to adjust” as outlined by Torok and Nicholls.  But this is internal monitoring as part of the process, not formal quality control.  Moreover, I remind Dr Ayers of the following:

“Generally, comparison observations for longer than five years were found to provide excellent comparison statistics between the old and new sites…… Comparisons longer than two years, and sometimes between one and two years, were also found to be useful if complete and of good quality… Poor quality comparisons lasting less than two years were generally found to be of limited use.” (Della-Marta et al, 2004).

The five years requirement has apparently now been reduced to one year- perhaps there was a journal article discussing this?  And what then of the stations with zero years of parallel observations?

7. Can you please provide details of the peer reviews of the two papers referenced by Dr Jones, namely

Della-Marta, P., Collins, D., Braganza, K. “Updating Australia’s high-quality annual temperature dataset” Australian Meteorological Magazine Vol. 53, no. 2, June 2004

and

Torok, S.J. and Nicholls, N. 1996. A historical annual temperature dataset for Australia. Australian Meteorological Magazine, 45, 251-260.

Scientific peer reviews are undertaken in confidence,… Thank you for the first straight forward answer to my questions.  I am satisfied with this.

8. Please provide complete details, including station metadata, of the reasons for the large adjustments to the temperature records of the following sites:

Omeo

Deniliquin Post office

Nhill

Wagga Wagga AMO

Kellerberrin

and of the following Urban sites (not used in climate analyses but adjusted):

Wangaratta Aero

Echuca Aerodrome

Benalla Shadford St

Dubbo Airport AWS.

I have asked our Climate Data Services Section to provide you with the specific data you have requested in your letter. Thank you in anticipation, as I hope this will answer some questions.  I trust that it will include some real explanations for the “subjective decisions” used to make adjustments at these sites.

Dr Ayers’ final paragraph:  No, this hasn’t addressed my concerns.  And I don’t believe I will be submitting a scientific paper anytime soon, as I don’t know any scientists or statisticians with the time or interest to assist me.      However, I will continue to debate scientific “facts”.  This issue will not go away.

In conclusion, Mr Burke, this hastily prepared, poorly researched, and carelessly written Ministerial letter, coming as it does more than three months after my letter to you, is of little worth.  It is nonsense to anyone with more than a superficial interest in meteorology.  It reflects poorly on your credibility as Minister responsible for the Bureau of Meteorology.

Yours sincerely

Ken Stewart

Advertisements

Official reply to my queries at last!

February 21, 2011

Here is the complete text of  the reply to my letter of 26 October 2010 to Tony Burke MP, the Minister responsible for the Bureau of Meteorology amongst other things.  Dr Ayers also included a hard copy of the Jones et al. paper referenced below.

I also include below for the public record previous correspondence with BOM.

Readers may make up their own minds about the adequacy of this official letter, but I will leave my comments to a reply post shortly.

The reply:

Dr Greg Ayers

Director of  Meteorology

GPO Box 1289

Melbourne VIC 3001

Dear Mr Stewart

Thank you for your letter of  26 October 2010 to the Minister for Sustainability, Environment, Water, Population and Communities, the Hon Tony Burke MP, titled “Formal complaint and request for Information- Bureau of Meteorology”.  I have been asked to reply on the Minister’s behalf.

Monitoring Australia’s climate is a high priority for the Bureau of M eteorology and we have developed a reference network of stations that have little or no urban influence to their climate records.  The data from this network are available free of charge at http://www.bom.gov.au/climate/change/.  The data which underpin this network are being continuously improved and added to through the digitisation of historic paper-based records and the collection of new observations.  We also committed (sic) to improving our data  analysis methods and therefore continually review these (see later) and adjust them where appropriate.

When assembling these data, we take great care to ensure that the science and methodologies underpinning our work are documented in the peer review scientific literature and thus made available to the public.  The website noted above provides links to scientific papers that describe in detail the data, processes and analysis methods that have been employed.  I urge you to familiarise yourself with this material as it is quite rich and authoritative.

We welcome examination and testing of our climate data and the analysis methods we use.  The Bureau receives much correspondence detailing findings, theories, observations and other matters.  We are unable to respond to all of these requests in detail, as to do so would distract us from critical operational duties.  The appropriate forum for review of our work is the scientific peer review journals.  A basic tenet of science is that critiques of scientific arguments should be subject to the same level of expert scrutiny as the original arguments.  Bureau scientists are more than happy to respond in detail to critiques of their work when they are published in this forum.

Specific to the queries set out in your letter, I offer the following comments:

1.  What explanation is there for the large discrepancy between the 100-year trend of the homogenised data from the 100 high quality sites, and the trend of the raw data from these and nearby sites?

The Bureau of Meteorology has assessed this issue by a comparison of the high quality datasets developed by Torok and Nicholls (1996) with raw climate data from the Bureau of Meteorology climate database.  In a recent analysis we have spatially interpolated temperature data across the continent to assess the differences between raw and homogenised data trends on Australia’s average temperature.  Doing so removes bias inherent in having monitoring stations clustered in particular areas and sparse in others.  I refer you to Figure 12 in Jones et al. (2009) which compares spatially interpolated raw and homogenised mean temperatures aggregated over Australia for the period of the historical warming from 1950 to the present.  The series labelled as AWAP (shown in green) is the average temperature for Australia using all raw monthly temperature data.  The series labeled (sic) as Torok and Nicholls (shown in black) shows the average temperature for Australia based on the annually homogenised high quality dataset.  Comparing these two series demonstrates that the warming trends are effectively the same for the raw and homogenised data.

2. Why, if adjustments “tend to be equally positive and negative across the network”, have the great majority of sites had adjustments that have resulted in an increase (sic) warming trend?

Details on the homogenisation process are available in two references that I understand have been provided to you by Bureau staff previously:  Della-Marta et al. (2004) and Torok and Nicholls (1996).  In addition the PhD thesis by Torok (1996) contains graphs of every adjustment applied in the analysis.

As noted earlier, the Bureau continually reviews the data analysis methods used and I assure you that an evaluation of potential bias in warming trends, either positive or negative, is firmly within the compass of that work.  We will publish our findings on this matter later in the year and we will forward you a copy of the journal paper as soon as it is available.

3. What explanation is there for the inclusion in the High Quality series of 15 sites previously excluded because of urban influences?

It is not clear to which 15 sites you are referring.  The current criterion for inclusion of a station in the data set is set out in the publication by Della-Marta et al. (2004), with operational updates made in latter years.  The decision to classify a station as urban or non-urban is made on the basis of evidence for an urban warming signal and the immediate environment of the station.  It also depends on the period of observation.  For example, the Darwin composite series is classified as urban if the pre-1941 data are used, and non-urban if data are limited to the post 1941 period.

4.  Why, in supposedly “High Quality” records has so much low quality data been included?

All data included in the data series are deemed to be of high quality on the basis of length of record and careful examination of the station records and meteorological recordings.  As emphasised in the peer-reviewed scientific publications cited above, the data series included have been chosen because they provide the longest and highest quality records in a particular region.  Further detailed descriptions of the high quality stations are available in the PhD thesis by Torok (1996).

5.  Have there been any further adjustments made to the Australian temperature data apart from those documented at the BoM website?  If so, kindly supply details of all reviews and adjustments to the Australian raw temperature including, but not limited to, Torok and Nicholls and Della-Marta et al.,

The three papers described above provide details about how the high quality station data have been prepared, with the thesis by Torok providing detailed accounts of adjustments at stations.  An updated summary of operational adjustments is under preparation and will be available later this year.  I will arrange for a copy to be sent to you after this is published in the scientific peer reviewed literature.

6.  Can you please provide details of the quality control checks on the homogenisation adjustments?

The homogeneity adjustments are part of improving the quality of climate data for climate change analysis.  The adjustments are described in the peer-reviewed scientific literature (most notably in the three papers cited above) and all the high quality data is available via the Bureau’s website, as previously noted.  The homogenisation procedure involves careful metadata checks and a number of robust statistical tests.  Uncertainties in calculating the homogeneity adjustments are minimised, for example, by having a large number of comparison sites available, very good metadata and a year or more of parallel observations for the same station.

7.  Can you please provide details of the peer reviews of the two papers referenced by Dr Jones?

Scientific peer reviews are undertaken in confidence, with only the internal and external reviewers, the authors, and the journal editors having access to the reviews.  I can assure you that all publications from the Bureau of Meteorology are subject to careful review and quality control.  Publishing our work in respected scientific journals assures that the work has been independently reviewed by experts and found to be sound.

8.  Please provide complete details for additional sites.

I have asked our Climate Data Services Section to provide you with the specific data you have requested in your letter.  I understand that in the past this Section has made a range of data available to you and also pointed you to the wide variety of data which are available on the Bureau’s website.

I trust my considered reply to your letter will address your concerns.  Should you have any further concerns about the validity of our data analysis methods, I urge you to submit your arguments to scientific journals that mandate independent peer review.  This will ensure that we can engage in a reasonable and orderly debate over scientific facts and further improve our understanding of Australian climate trends.

Yours sincerely

(DR GREG AYERS)

DIRECTOR OF METEOROLOGY

10 February 2011

References

Della-Marta P., Collins C. And Braganza K. (2004), Updating Australia’s high quality annual temperature dataset, Australian Meteorological Magazine 53, 75-93.

Jones D.A., Wang W. And Fawcett R. (2009), High-quality spatial climate data-sets for Australia, Australian Meteorological Magazine 58, 233-248.

Torok, S. (1996), The development of a high quality historical temperature data base for Australia, PhD Thesis, School of Earth Sciences, University of Melbourne.

Torok S.J. and Nicholls N. (1996), A historical annual temperature dataset for Australia, Australian Meteorological Magazine 45, 251-260.

My letter to Tony Burke MP

26 October 2010

The Hon Tony Burke MP

Minister for Sustainability, Environment, Water, Population and Communities

PO Box 6022
House of Representatives
Parliament House
Canberra ACT 2600

Dear Sir,

Formal Complaint and Request for Information- Bureau of Meteorology

Given the importance of the consequences of a changing climate, the government and the public is justifiably interested in getting the most accurate picture of Australia’s temperature record.  For some months I have been comparing the Australian High Quality Temperature Sites’ adjusted data with raw data from those sites and nearby open and closed sites.  Data have been obtained from the Bureau of Meteorology’s excellent website.  The 100 High Quality (HQ) sites are used by BOM in their analyses of Australia’s climate.

I have published the results online at http://www.kenskingdom.wordpress.com .

My analysis has revealed apparent significant discrepancies between the HQ record and the raw data on which it is based.

This is problematic as Dr David Jones, Head of Climate Monitoring and Prediction, assured me in April that

“On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).”

Despite numerous requests via email and letter, Dr Jones has not responded to the issues which I have since outlined to him, nor has he answered three simple questions I put to him.  The only response was an anonymous email from Webclim suggesting that I publish a scientific paper before I get any answer.  Previous correspondence is enclosed.

In view of Dr Jones (and BOM’s) apparent refusal to answer my queries, I wish to make a formal complaint, and ask you to investigate this unwillingness to comply with standards of openness explicit in the APS Values and Code of Conduct:

“Openness is at the core of Australia’s modern system of government. It is essential in a healthy democracy that members of the public have the opportunity to contribute to policy development and decision-making, and that there is public scrutiny and accountability of government. Public access to information in the possession of government agencies helps to make this possible.”

Further, I am asking for answers, through you, to the following questions:

1.  What explanation is there for the large discrepancy between the 100-year trend of the homogenised data from the 100 High Quality sites, and the trend of the raw data from these and nearby sites?

2. Why, if the adjustments “tend to be equally positive and negative across the network”,  have the great majority of sites had adjustments that have resulted in an increased warming trend?

3. What explanation is there for the inclusion in the High Quality series of 15 sites previously excluded because of urban influence?

4. Why, in a supposedly “High Quality” record, has so much low quality data been included- stations with short records (e.g. Woomera, Giles), large gaps infilled with estimates (e.g. Wilcannia, Cape Borda) or with data from sites many kilometres away (e.g. Newman), and records constructed by combining data from stations with no overlap at all (e.g. Port Hedland, Bourke, Cashmore)?

5.  Have there been any other adjustments made to the Australian temperature data apart from those documented at the BOM website?  If so, kindly supply details of all reviews and adjustments to the Australian raw temperature data including, but not limited to, Torok and Nichols, and Della-Marta et al.

6.  Can you please provide details (including dates, personnel, methods, results) of the quality control checks on the homogenisation adjustments.

7.  Can you please provide details of the peer reviews of the two papers referenced by Dr Jones, namely

Della-Marta, P., Collins, D., Braganza, K. “Updating Australia’s high-quality annual temperature dataset” Australian Meteorological Magazine Vol. 53, no. 2, June 2004

and

Torok, S.J. and Nicholls, N. 1996. A historical annual temperature dataset for Australia. Australian Meteorological Magazine, 45, 251-260.

8. Please provide complete details, including station metadata, of the reasons for the large adjustments to the temperature records of the following sites:

Omeo

Deniliquin Post office

Nhill

Wagga Wagga AMO

Kellerberrin

and of the following Urban sites (not used in climate analyses but adjusted):

Wangaratta Aero

Echuca Aerodrome

Benalla Shadford St

Dubbo Airport AWS.

I look forward to your reply.

Yours sincerely

Ken Stewart

Copy of email and hard copy sent to Dr Jones 08 October 2010

08 October 2010

Dr David Jones

Head of Climate Monitoring and Prediction
National Climate Centre
Bureau of Meteorology
GPO Box 1289, Melbourne
Victoria 3001

Dear Sir,

Attached copy of email sent to Webclim and yourself today.

Yours sincerely

Ken Stewart

Dear Dr Jones

I refer to my previous correspondence with you:

1. My emails dated 19/04/2010; 24/04/2010 and replies of 23/04/2010 and 25/04/2010.

2. My email dated 27/07/2010 (copy included below).

3. My letter dated 31/08/2010 (copy included below).

and 4. Email from Webclim (below) dated 09/09/2010.

As it is now at least one month since my letter (“3.”) should have been received, I am disappointed that neither you nor anyone else has been able to respond to the issues raised at https://kenskingdom.wordpress.com/ , and in my letter, or to the specific questions I asked.

I am disappointed that the only response I have had to my email of 27/07/2010 and my letter of 31/08/2010 has been an anonymous, possibly automated, email from Webclim.

I am disappointed that these issues and questions apparently will not receive serious consideration unless published in a scientific journal.  I do not intend to write a scientific paper, but as an Australian taxpayer and concerned citizen I have noticed some apparent discrepancies and I would like my specific questions answered by an identifiable human being.

I ask again:

1.  In view of your statement,

“On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).” ,

can you please explain the apparent discrepancy between the raw and High Quality data?

2.  Can you please provide details (including dates, personnel, methods, results) of the quality control checks on the homogenisation adjustments?

3.  Have there been any other adjustments made to the Australian temperature data apart from those documented at the BOM website?  If so, kindly supply details of all reviews and adjustments to the Australian raw temperature data including, but not limited to, Torok and Nichols, and Della-Marta et al.

I look forward to your reply within 14 days.

A copy of this follows by surface mail.

Yours sincerely

Copy of my email of 27/07/2010:

To: David Jones

Sent: Tuesday, July 27, 2010 1:29 PM

Subject: High quality temperature record

Dear Dr Jones

You may remember answering my queries in April regarding the HQ record for Queensland.  Thank you for your responses.  Since then I have completed a comparison of the HQ data with the raw station data for all 100 non-urban sites.

The results are published at https://kenskingdom.wordpress.com/2010/07/27/the-australian-temperature-record-part-8-the-big-picture/

I would be interested in your response to the issues raised, especially in view of your claim that

“On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes). ”

I will be glad to publish your response in full.

Yours sincerely

Ken Stewart

(Copy of my letter of 31/08/2010)

Dr David Jones
Head of Climate Monitoring and Prediction
National Climate Centre
Bureau of Meteorology
GPO Box 1289, Melbourne
Victoria 3001

Dear Sir

Given the importance of the consequences of a changing climate, the government and the public is justifiably interested in getting the most accurate picture of Australia’s temperature record.

I have recently completed a comparison of the Australian High Quality Temperature Sites’ adjusted data with raw data from those sites and nearby open and closed sites.

I have published the results online at http://www.kenskingdom.wordpress.com

In an email to me on 25 April 2010 you stated:

“On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).”

My comparison shows that:

  • Of the 100 High Quality sites, 22 have been cooled, 22 have had essentially no change to their trends, and 56 have been warmed by the adjustment process.
  • The average difference between raw and adjusted trends for the period 1910 – 2009 across the 100 non-urban sites is about 0.25 degree Celsius per 100 years (mean: 0.23; median: 0.275).
  • The average temperature trend has been increased from + 0.6 degree C to + 0.85 C for the period 1910 – 2009.
  • The published Time Series graph shows a warming trend for Australia of 0.1 C per decade (1.0 C per 100 years) which is 0.4 C per 100 years greater than the anomaly trend of the raw data.
  • 15 of the 100 sites were originally listed as Urban by Torok and Nichols, but have been included in the record.
  • Although a long period of continuous records is desirable for a High Quality site, and Torok and Nichols regarded 80 years as being desirable, many of the sites have much less than 80 years of data, and large gaps in the record.  These missing years have been infilled with estimated data or with data from sites from many kilometres away.
  • Although Della-Marta et al consider that 5 years of overlap provides excellent data comparison, and 2 years can be useful if good quality, many records are constructed by combining data from stations with no overlap at all, or from different climatic areas many kilometres away.

In view of your above mentioned statement, can you please explain the apparent discrepancy between the raw and High Quality data?

Can you please provide details (including dates, personnel, methods, results) of the quality control checks on the homogenisation adjustments?

Have there been any other adjustments made to the Australian temperature data apart from those documented at the BOM website?  If so, kindly supply details of all reviews and adjustments to the Australian raw temperature data including, but not limited to, Torok and Nichols, and Della-Marta et al.

I look forward to your response to these questions and your comments on the points raised.

Yours sincerely

(Copy of email from Webclim)

—– Original Message —–

From: Web Climate requests

To:

Sent: Thursday, September 09, 2010 10:12 AM

Subject: Email response [SEC=UNCLASSIFIED]

Thank you for your analysis/hypothesis

As part of the scientific process you may wish to prepare and submit your work to a scientific journal. This will then mean that your work will be given serious scientific consideration.

There are a number of scientific journals worth considering. See for example: http://gcmd.nasa.gov/Resources/pointers/news_journ.html

It is difficult for the Bureau of Meteorology to assess work that has not been published. For example, the pure and applied (research) work carried out by scientists at the Bureau have to comply with the publication process before further assessment of the applicability of the work (analyses) is carried out. This conforms to standard scientific process and procedure.

Good luck with your work.

regards,

Webclim

National Climate Centre-Climate Information Services

Email:   webclim@bom.gov.au

Copy of emails with BOM- April 2010:

Ken,
the high-quality Australian data is all available at http://www.bom.gov.au/climate/change/hqsites/ . A description of how these data are assembled is provided at http://www.bom.gov.au/climate/change/hqsites/about-hq-site-data.shtml .
Regards,
David
  1. I have read the 1996 paper by Torok and Nicholls.  Where can I find the details of any other adjustments?
The update to Torok and Nicholls is described in
Updating Australia’s high-quality annual temperature dataset /  

Della-Marta, P., Collins, D., Braganza, K. 2004

Australian meteorological magazine. Vol. 53, no. 2, June 2004. pp. 75-93

 

  1. I note that Innisfail is listed on the HQ page as “Urban”.  When did Innisfail’s population exceed 10,000?
Urbanisation does not simply relate to population. It also can relate to the nature of the site’s surrounds.
  1. The Torok and Nicholls paper lists Cairns AMO, Rockhampton AMO and Gladstone as Urban, but they are shown as Rural on the HQ page for Queensland.  Why is this?
Each of these is well outside of the town centre. We find no evidence in our analyses urban warming at these sites – Cairns and Rockhampton are at the airports and Gladstone is on a high hill outside of the urban influence..
  1. Cooktown’s raw data for the 3 stations shows practically no warming at all over 100 years, yet the High Quality data (for Cooktown Mission Strip) shows a warming of roughly 0.9 degrees.  Yet Port Douglas shows only about 0.25 degree warming.  Can you please comment on this.
You are merging data from different stations. That is why your trends are inconsistent with the data.
  1. Similarly, Sandy Cape Lighthouse shows about 0.45 degrees trend, but the HQ data shows a trend of approximately 1.2 degrees/100 years. Nearby sites- Maryborough shows approximately 0.3 degrees, Childers about 0.4, and Gympie 0.3 degrees.  Can you please comment on this.
I cannot see the data you are describing.
  1. Similarly, Roma’s warming trend has been increased from 0.6 to about 1.5 degrees.  Miles shows about 0.4, Dalby about 0.55, Mitchell about 1.0, and Charleville’s HQ data shows about 0.6.  Can you please explain how the Roma data was developed.
Here is the raw and corrected data for Roma. The site has moved a number of times and the screen has changed.
Here is the list of changes to the site which are related to the corrections. The main change relates to a major site move which accounts for a large part of the inhomogeneity.
 

METADATA Summary

Roma,043091,043030
10/1897: Stevenson screen supplied.
02/1908: First correspondence.
12/1908: Screen moved due to building.
11/1912: New large screen.
10/1916: Poor observations during the 1910s.
11/1929: Screen moved 50 feet due to new shed and incinerator.
10/1941: Screen needs to be repaired.
10/1962: Site has deteriorated due to bitumen and buildings.
01/1971: Temporary site during building.
09/1972: Move to new PO.
09/1983: Site moved 50 m south to better site.
01/1992: Move to composite site.
04/1994: Bubbles in Min Thermometer
02/1997: AWS (Almos) Installed (28/02/1997)
02/1997: SITE MOVE- Short distance West (@8/02/1997)
1997-2002: Routine AWS upgrades and maintenance.

Please consider the environment before printing

 

Dr David Jones
Head of Climate Monitoring and Prediction
National Climate Centre
Bureau of Meteorology
GPO Box 1289, Melbourne
Victoria 3001, Australia


From: Cathy Toby On Behalf Of Web Climate requests
Sent: Monday, 19 April 2010 14:23
To: David Jones
Subject: FW: Questions re high quality data sites [SEC=UNCLASSIFIED]

Hi David
I’m not sure who in CAS is best able to answer this one – could you forward it on please?
thanks
Cathy

Webclim
Climate Information Services
National Climate Centre
GPO Box 1289 Melbourne Australia 3001

Phone +61 3 9669 4082,  Fax +61 3 9669 4515
Email: webclim@bom.gov.au

 


From:
Sent: Monday, 19 April 2010 13:50
To: Web Climate requests
Subject: Questions re high quality data sites

Dear Sir/Madam,
I have been looking at the Australian High Quality Climate Site Data and comparing them with annual means calculated from the data for these stations at the Climate Data Online page.
I have some questions regarding the Queensland sites.  Could you please assist with these:
  1. I have read the 1996 paper by Torok and Nicholls.  Where can I find the details of any other adjustments?
  2. I note that Innisfail is listed on the HQ page as “Urban”.  When did Innisfail’s population exceed 10,000?
  3. The Torok and Nicholls paper lists Cairns AMO, Rockhampton AMO and Gladstone as Urban, but they are shown as Rural on the HQ page for Queensland.  Why is this?
  4. Cooktown’s raw data for the 3 stations shows practically no warming at all over 100 years, yet the High Quality data (for Cooktown Mission Strip) shows a warming of roughly 0.9 degrees.  Yet Port Douglas shows only about 0.25 degree warming.  Can you please comment on this.
  5. Similarly, Sandy Cape Lighthouse shows about 0.45 degrees trend, but the HQ data shows a trend of approximately 1.2 degrees/100 years. Nearby sites- Maryborough shows approximately 0.3 degrees, Childers about 0.4, and Gympie 0.3 degrees.  Can you please comment on this.
  6. Similarly, Roma’s warming trend has been increased from 0.6 to about 1.5 degrees.  Miles shows about 0.4, Dalby about 0.55, Mitchell about 1.0, and Charleville’s HQ data shows about 0.6.  Can you please explain how the Roma data was developed.
Thank you for your assistance.
Yours sincerely
Ken Stewart

Final reply from Dr Jones: 25 April 2010

The regions are described at http://www.bom.gov.au/climate/change/about/temp_timeseries.shtml .

Most of the metadata only exists on paper files as it can date back more than a century. If you contact your local regional office they should be able to make access to the paper copies available to you – this is very time consuming.

On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).

Regards,

David

________________________________________
From:
Sent: Saturday, 24 April 2010 8:02 AM
To: David Jones
Subject: Re: Questions re high quality data sites [SEC=UNCLASSIFIED]

Dear Dr Jones,

Thank you for your prompt reply.  I have read with interest the Della-Marta et al paper.

Thank you especially for the metadata re Roma.  Is metadata available electronically for all HQ stations, and if so, where?

Another question- what are the boundaries for the different regions in Australia e.g. North Australia, South East Australia, etc.?

Many thanks

Ken

The Danger of Hype

February 14, 2011

Ken Stewart, 14 February 2011; updated 20 February

Prior to the arrival of Tropical Cyclone Yasi, Premier Anna Bligh repeatedly warned Queenslanders that Yasi would be very severe and dangerous, and urged people in its path to evacuate, repeating warnings from the Bureau of Meteorology:

“This impact is likely to be more life-threatening than any experienced during recent generations,” the Bureau of Meteorology said this morning. (Feb 02 2011)

People heeded the warnings and although there was much damage, only one life was lost.

However, the reality of Yasi’s impact was quite different from the prediction.  Using data from Yasi’s approach to Willis Island, I calculated estimated maximum speed of 220 to 240 km/hr at landfall.   This was borne out by scientific assessment of damage in the area:

The CTS team leader in the field, Dr Geoff Boughton, said that the analysis of damage to simple structures throughout the region indicated that the wind speeds on the ground in Tropical Cyclone Yasi were less than those expected in a Category 5 event.

Using techniques developed and refined in previous cyclones, the CTS team has formed a preliminary view that the maximum wind speed in Cyclone Yasi was about the same as that in Tropical Cyclone Larry.

“We estimate that the gust wind speeds in some of the most affected areas were about 220 km/h” Dr Boughton said.”

http://www-public.jcu.edu.au/news/JCUPRD1_071493

In other words Yasi was a strong Cat 3 or very low Cat 4, not Cat 5.  There is no evidence for winds of 290km/hr .  The danger from Cyclone Yasi was exaggerated and over-hyped.

What’s the big deal? you may ask.  Lives were saved.

True.  Hyping the danger was a good short term tactic and worked.  However, this is not a good long term strategy in our fight to defend ourselves from nature’s extremes.

The people of North Queensland may well say, “Well if that was 290 km/hr winds, the damage was bad, but not too bad.  We’ll be right next time.”

But the damage from a cyclone with real 290 km/hr winds will be many times worse than that caused by Yasi.

This is from BOM’s FAQs about cyclones  http://www.bom.gov.au/cyclone/faq/index.shtml

12. How does the amount of damage caused by a cyclone increase as the wind speed increases?

Or to rephrase the question: Would a cyclone with wind gusts of 280 km/h cause twice the damage of a similar sized cyclone with wind gusts of 140 km/h? No – it would cause hundreds of times more damage.

As wind speed increases the power of the wind to do damage increases exponentially. Hence a category 5 severe tropical cyclone (with wind gusts > 280 km/h) has the potential to do around 250 times the damage of a Category 3 severe tropical cyclone (with wind gusts of 165 km/h). This underscores the importance of the category system.

Graphical representation of the variation of damage with wind speed.

I have marked in the maximum gusts from Yasi (61 m/sec) and the predicted strength (80.5 m/sec).  Wind increases 33%, damage increases by about 1100%!  (Don’t ask me how they get “250 times” the damage for 165-280km/hr increase!)

This is serious!  With the strong La Nina, there are likely to be more cyclones this season.  People lulled into a false sense of security by believing they have survived a Category 5 cyclone may be killed.

Here’s a graph of annual SOI values  since 1910.  Notice the dip in the late 1970s and the recent rise.  If this trend continues, we may be entering a phase of more La Ninas and fewer El Ninos in coming years- meaning more cyclones.

What Australia-wide strategy is needed?

  • Educate the public about the realities of La Ninas, cyclones, floods, droughts, fires.
  • Mandate storm shutters for windows and household storm shelters in cyclone prone areas.
  • Have highly visible marks on every power pole and public structure showing highest known storm tide or flood height.
  • Mandate flood height information to be part of every real estate transaction and on every rate notice.
  • And in all disaster events, tell the truth, don’t exaggerate. The media will do that anyway.  Give factual details in a calm clear manner.

Hype is dangerous.

 

How Strong Was Yasi?-Update 11 Feb

February 7, 2011

Ken Stewart, February 2011

Update Friday Feb 11 8.12pm:  On ABC news tonight, a report from James Cook University, whose scientists have established Yasi’s speed, at

http://www-public.jcu.edu.au/news/JCUPRD1_071493

“The CTS team leader in the field, Dr Geoff Boughton, said that the analysis of damage to simple structures throughout the region indicated that the wind speeds on the ground in Tropical Cyclone Yasi were less than those expected in a Category 5 event.

Using techniques developed and refined in previous cyclones, the CTS team has formed a preliminary view that the maximum wind speed in Cyclone Yasi was about the same as that in Tropical Cyclone Larry.

“We estimate that the gust wind speeds in some of the most affected areas were about 220 km/h” Dr Boughton said.”

In fact that’s at the low end of my estimate!


On Wednesday 02 February 2011, TC Yasi struck Far North Queensland.  Despite the enormous devastation in the Cardwell-Mission Beach-Tully area, thanks to Emergency Services Queensland, Anna Bligh, and the Bureau of Meteorology (BOM), people were well prepared, evacuated when it was thought necessary, and only one life was lost.

However, many people have noticed that Yasi was nowhere near as strong as expected.

The Bureau of Meteorology estimated that windspeeds would reach 290kph near the centre, and at 8.00pm warned these could be expected between Cairns and Ingham.  This estimate was made from analysing radar and satellite data.  But at 4.33p.m. BOM’s technical advice estimated winds at the centre as being 205kph (my emphasis):

Technical brief issued by BOM at 6:33 UTC.

REMARKS:
The latest imagery shows Yasi as very symmetric showing a well defined eye with surrounding deep convection. Dvorak intensity: Eye pattern white surround [6.0] with OW/W [0.5] eye adjustment giving DT=6.5, adj. MET=6.0. FT/CI=6.5. Max winds estimated at 110 knots [205 km/h] [AMSU/SATCON estimates at 125kn [1min]].
Surface observations indicate hurricane force winds extend about 50 nm [95 km] to the southwest of the track.

As well, they had access to data from Willis Island which was right in Yasi’s path and which transmitted data until just before the eyewall passed over it.  Yet they still maintained Yasi at Cat 5, probably as a precaution.    They received unjustified criticism over the Toowoomba and Lockyer floods so government and BOM were taking no chances.   What most people don’t realize is that cyclone category is not an exact statement but a warning.  From the BOM website:

The severity of a tropical cyclone is described in terms of categories ranging from 1 to 5 related to the zone of maximum winds. An estimate of cyclone severity is included in all tropical advices. Remember that the Warning Service is not designed to give an exact statement of conditions at individual locations but will give a general idea of the expected worst conditions.

http://www.bom.gov.au/cyclone/about/

And while no more precise estimate of wind speed can be made until completion of engineering analysis of the damaged areas, news reports are still universally reporting winds of 290kph.  In the meantime, here is an alternative estimate.

Although the maximum recorded windgust at Lucinda was 185kph, this was 50km south of the centre and about 35km from the eyewall, and a look at the data shows the wind changing direction every few minutes, possibly an effect of the nearby topography.  These speeds are probably not reliable.

I have used data from Willis Island to estimate windspeeds in the lead  up to the crossing at Mission Beach.

Willis Island was directly in the path of Yasi’s eye.  It transmitted data right from  the edge of the eyewall.  This is its final radar image (courtesy of Watts Up With That):

Here’s the graph of windspeed:

and the table of observations:Notice the wind suddenly changed from south at 6.00 a.m  to north-west at 6.15 a.m.  with no drop in speed (102kph sustained).  I can think of 3 explanations.

  1. Possibly the north face of the eyewall passed over it.  However, the radar image at 8.00 shows the island right in the firing line, and still some distance away.  The cyclone would have had to change course.
  2. Alternatively, the eye passed over for about 15 minutes and the calm was not recorded.  This is odd.  We were told the calm eye would take an hour to pass over.  Besides, the radar image shows the eye still to arrive.  The wind increased to 141kph, gusting to 185kph, at 8.10a.m. The anemometer then ceased operations, although the barometer recorded decreasing pressure (to 938hPa at 9.00) then increasing to 940.1 at 10.00a.m.  The continued drop in pressure means the wind might have increased even further by perhaps 20 to 30kph, making the top gust at around 215kph.
  3. Perhaps the wind vane was damaged at 6.15?  Then for two hours the cyclone travelled 60-70km closer and the wind increased by 40kph sustained and 46kph gusts.  This is most likely.

The 8.00 a.m. radar image shows Willis island was approximately 15-20km from the eyewall and 30-35km from the centre.  Maximum speed is reached at the eyewall.  I used the data to make a plot of the data including an interpolation for 5.45 a.m., and  extrapolating to 8.30 a.m., the approximate time of the eyewall’s arrival.

As you can see I used 3 estimates for the 8.30 windspeed: the BOM 4.33 p.m. estimate of 205kph; the 8.12 p.m. cyclone advice estimate of 290kph, and 231kph, the AMSU/SATCON estimate and just above the borderline Cat 3/Cat 4 speed.

I believe that the estimate of 290kph cannot be supported- it appears too high.  Further, this is not supported by BOM’s 4.33 p.m. technical brief.  However it appears that 205kph could be too low for 8.30pm at Willis Island.  230kph appears to be closer.

The cyclone was travelling at about 30kph at this time, so every hour is approximately 30km.  Using 9.00 a.m. as the time of the cyclone centre passing just a few km to the south of Willis Island with a QNH (barometric pressure) of 938hPa, I constructed a plot of observed windspeeds at approximate distances from the centre.

The horizontal scale is distance from the centre in kilometres.

Therefore, a defensible estimate for windspeed in the Cardwell-Mission Beach area would be in the range 220-240kph.  This indicates it was a low Cat 4, not Cat 5.

Yasi was indeed an enormous system in area covered by cloud, the largest we’ve seen in the satellite era.  The zone of maximum destruction (and winds) extended from roughly Silkwood to Cardwell, a distance of about 60km.  The storm was roughly the same strength as Cyclone Larry but took longer to pass.  Remarkably, it was still classed as a cyclone at Julia Creek, the furthest inland a cyclone has been recorded.

Contrary to many alarming reports, it was not the deepest cyclone (<926hPa, Mourilyan Mill, 1918) nor the highest storm surge (Bathurst Bay >10m, 1899 or Mission Beach 3.6m 1918) nor the the most rain (907mm in 24 hours at Crohamhurst, 1893) nor the deadliest (307 known fatalities, Bathurst Bay, 1899).

Which is no consolation for the residents of Cardwell, Tully, and Mission Beach.