Tag Archives: pages2k

Okshola: which way is up?

The recent revisions to PAGES2K included a dramatic flipping of the Hvitarvatn varve series to the opposite orientation used in the 2013 version used in IPCC AR5. Together with other changes (such as a partial – but still incomplete – removal of contaminated sediments from the Igaliku series), this unwound most of the previous difference […]

Revisions to Pages2K Arctic

Kaufman and the PAGES2K Arctic2K group recently published a series of major corrections to their database, some of which directly respond to Climate Audit criticism. The resulting reconstruction has been substantially revised with substantially increased medieval warmth. His correction of the contaminated Igaliku series is unfortunately incomplete and other defects remain.

A New Alaskan d18O Series

PAGES2K Arctic introduced a lake sediment d18O series from Kepler Lake, Alaska that hadn’t been used in previous studies. Although O18 data is a workhorse of paleoclimate, O18 data from Alaska (or, for that matter, anywhere in the Arctic hemisphere between 90E and 90W – going east) is very scarce. Thus, the appearance of a […]

Varved Inconsistency

Since AR4, there have been a series of new multiproxy studies, several of which were cited in AR5 (Mann et al 2008; Ljungqvist et al 2010; Christiansen and Ljungqvist 2012; Shi et al 2013). A distinctive feature of these and other recent multiproxy studies is the incorporation of varve thickness and near-equivalent mass accumulation rate […]

More on Hvitarvatn Varves

In a previous post on PAGES2K Arctic, I pointed out that they had used the Hvitarvatn, Iceland series (PAGES2K version shown below), upside-down to the interpretation of the original authors (Miller et al), who had interpreted thick varves as evidence of the Little Ice Age. A few days ago, Miller and coauthors archived a variety […]

PAGES2K Online “Journal Club”

I’m listening to a presentation by PAGES2K authors sponsored by Nature: http://blogs.nature.com/ofschemesandmemes/2013/05/02/npg-journal-club-how-has-earths-climate-changed-in-the-past-2000-years-npgjclub#comment-1503 Started at 11 am Eastern. 11:30. Open for questions. I have submitted the following: Can you explain the decision to label the article as only a “Progress Article”, rather than a Research Article? Nature’s definition of Progress Articles http://www.nature.com/ngeo/authors/content_types.html says that such articles […]

More Kaufman Contamination

Kaufman and paleo peer reviewers ought to be aware that the recent portion of varve data can be contaminated by modern agriculture, as this was a contentious issue in relation to Mann et al 2008 (Upside Down Mann) and Kaufman et al 2009. Nonetheless, Kaufman et al 2013 (PAGES), despite dozens of coauthors and peer […]

PAGES2K: Gifford Miller vs Upside-Down Kaufman

The PAGES2K Arctic reconstruction uses Gifford Miller’s Hvitavatn (Iceland) data upside down. The error “matters” because this series is one of rather few PAGES2K series that show a Hockey Stick. Such gross errors ought to be corrected before the data is cited for policy purposes or said to confirm previous studies.

PAGES2K Reconstructions

The PAGES2K article to be published tomorrow will show eight regional reconstructions, which are plotted below. In today’s post, I’ll try to briefly summarize what, if anything, is new about them. Antarctica: This is a composite of 11 isotope series (mostly d18O). It includes some new data (e.g. Steig’s new WAIS series) and some long […]

PAGES2K South America

A commenter observed that the forthcoming PAGES2K received over 50 pages of review comments from one reviewer. One wonders what he had to say about the PAGES2K South American network which has some very odd characteristics. Here is a list of proxies with a couple of interesting features highlighted. First, note that the “proxy” network […]