January 2007 ISSUE
Readers’ Forum
Turtle Mountain Overstatement
Re: Back to the Basics in the Foothills, The PEGG, November 2006.
This article overstates the role of the Fold-Fault Research Project in the Turtle Mountain Monitoring Project and does not give proper credit to the other members of the team. The article states that “the Fold-Fault Research Project initiated a geological and geophysical monitoring project to predict future slides” at Turtle Mountain. The project, however, was actually commissioned in 2003 by the Government of Alberta in order to establish a near-real time monitoring system for slide development at Turtle Mountain and to reduce the risk to communities and infrastructure below the mountain.
The work was divided into more than a dozen separate work packages that were awarded to a number of APEGGA member consulting firms and individuals, along with provincial government agencies and researchers from several Canadian universities. The Fold-Fault Research Project’s participation was under a work package for the operation of a televiewer in a borehole drilled by others near the summit of Turtle Mountain. The work package was also to process and interpret data from the televiewer and surface geological mapping, as a contribution to updated geological mapping and characterization of the bedrock structure in Turtle Mountain.
The article also states that “researchers actually feared losing the drill rig into a void space” while drilling the borehole near the summit of Turtle Mountain. This was not the case.
The project team members that were responsible for drilling this borehole
recognized this hazard while planning the work and selected a drilling location
where the borehole could be safely drilled. To do otherwise would have been irresponsible
and a risk to the safety of workers and equipment.
For further information on the Turtle Mountain Monitoring Project, visit
www.ags.gov.ab.ca/activities/Turtle_Mountain/mainpage.htm.
Andrew Bidwell, P.Eng.
Calgary
Academy Confidence Not as Strong as Presented
Re: Hockey Stick Curve, Other Data Thoroughly Verified, J. Edward Mathison, P.Geol., Readers’ Forum, The PEGG, November 2006.
The author states that “Earth’s temperature record over the last few thousand years, the famous hockey stick of Mann et al., has been substantiated by two independent studies using different data sets” and “has been verified by the National Academy of Sciences in the U.S.” Closer inspection of the academy report, available for free at www.nap.edu/catalog/11676.html, reveals
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It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries. This statement is justified by the consistency of the evidence based on a wide variety of geographically diverse proxies.
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Less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600. Presently available proxy evidence indicates that temperatures at many, but not all, individual locations were higher during the past 25 years than during any period of comparable length since A.D. 900. The uncertainties associated with reconstructing hemispheric mean or global mean temperatures from these data increase substantially backward in time through this period and are not yet fully quantified.
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Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900 because of sparse data coverage and because the uncertainties associated with proxy data and the methods used to analyze and combine them are larger than during more recent time periods.
It is perhaps unsurprising that it has become warmer since the Little Ice Age, but perhaps Mr. Mathison could explain how the terms “less confidence” and “very little confidence” can be interpreted as “verified.”
Furthermore, the work of Mann et al. was savaged by a recent congressional investigation led by Dr. Edward Wegman, chairman of the National Academy of Sciences Committee on Applied and Theoretical Statistics. This report, available at http://energycommerce.house.gov/108/home/07142006_Wegman_Report.pdf, recognizes flaws in the methods used by Mann et al. and states: “The assessments that the decade of the 1990s was the hottest decade in a millennium and that 1998 was the hottest year in a millennium cannot be supported by the [Mann et al.] analysis. As mentioned earlier in our background section, tree ring proxies are typically calibrated to remove low frequency variations.
“The cycle of Medieval Warm Period and Little Ice Age that was widely recognized in 1990 has disappeared from the [Mann et al.] analyses, thus making possible the hottest decade/hottest year claim. However, the methodology of [Mann et al.] suppresses this low frequency information. The paucity of data in the more remote past makes the hottest-in-a-millennium claims essentially unverifiable.”
Mr. Mathison also dismisses the points of climate change sceptics by stating that “rarely do climate change sceptics publish refereed articles in scientific journals.” This statement is ironic in that the Wegman report examined the social networks of published temperature reconstruction authors and concluded that the peer review process was “not sufficiently independent.”
It further recommended that, contrary to what is presently the case, that the authors of policy-related documents such as the Intergovernmental Panel on Climate Change report should not be the same people as those that constructed the academic papers.
I encourage all readers to download the documents cited and draw your own conclusions regarding how much confidence should be placed in temperature reconstructions such as those of Mann et al.
Dr. Nathan Schmidt, P.Eng.
Edmonton