Monday, February 10, 2014

Answering a Gish Galloping critic, Part 1

Apparently my post listing 36 publications that all show a "hockey-stick" has attracted some attention, including from a self-proclaimed paleogeneticist who claims that he's an expert in climate models.  I'm putting my response here, as responding to the Gish Gallop of BS he wrote would take far too much space in the comments section of that post.  If he doesn't like it?  Too bad.


Claim: "As a paleogeneticist, I must use climate models. This means that I understand their defects."

Response:  A paleogeneticist is an expert in ancient DNA, not climate.  I fail to see how a background in paleogenetics qualifies you as a climate modeler.

Claim: "Mann's "hockey stick" had two features that, when it emerged, astonished all of us in the science in two respects:
(a) The "Little Ice Age" was not recorded in the proxies that Mann used. And yet this climate phenomenon was well documented."

Response: Utterly bogus.  If you bother to examine Figure 3 in Mann et al. (1999), you will see a clear decline in Northern Hemisphere temperatures during the Little Ice Age.  Mann et al. specifically highlighted a -0.02ºC/century trend between the middle of the Medieval Warm Period (AD 1000) and the end of the Little Ice Age (AD 1850).

Claim: "(b) The statement that this was the "warmest year on record", when we all knew the evidence that the Medieval warm period was as warm as today, the Minoan and Roman warm periods were warmer, and earlier periods were MUCH warmer (we just got fossil human footprints in England ~750,000 years ago)."

Response: Again, utterly bogus.   You're relying on ancient anecdotal evidence from one region of the world for your Roman and Minoan warm periods.  Where is your data actually supporting your contention?  Marcott et al. (2013) showed that neither the Minoan nor the Roman warm periods were particularly warm worldwide.  But of course, you already knew that since you claim to have read every one of the 36 papers on my list, right?

Claim: "Further, we know WHY it was wrong. We know the statistical mistakes that he made. We know the data that he chose to not include. We know that his proxies do not track the record in the last 30 years."

 Response: Ah, yes, the McIntyre and McKitrick claim.  You do know that McIntyre and McKitrick were utterly and devastatingly debunked by Wahl and Ammann (2007), who showed that McIntyre and McKitrick's findings were based on a flawed analysis, right?  As for your claim about the tree ring proxies, the post-1960 divergence problem is well known and has been the subject of intense research.  We know that high-latitude tree rings tracked temperature very well between AD 1880 and AD 1960 (Briffa et al. 1998). We also know that the divergence problem is limited to high-latitude tree rings and is absent from mid-latitude tree rings (Cook et al. 2004) and likely has an anthropogenic cause (D'Arrigo et al. 2008).  However, your argument flunks a more basic test.  We have actual temperature measurements of the last 134 years and do not rely on tree ring proxies to tell us what temperatures have done since 1960.

Claim: "All while putting in9 figures that...um... do NOT show a hockey stick. Rather than showing the flat temperature during the Medieval warm period, the Medieval warm period is back."

Response: Did you even bother looking at the graph I included at the end?  You know, the one created using Marcott et al. (2013) RegEM reconstruction?  It showed that we had passed the Medieval Warm Period by AD 1940.  And it's far from the only one to show that.  Try reading Moberg et al. 2005, Oerlemans 2005, Wilson, et al. 2007, Kaufman, et al. 2009, Kellerhals et al. 2010, Thibodeau et al. 2010, Büntgen et al. 2011, Kemp et al. 2011, Martin-Chivelet et al. 2011, Spielhagen et al. 2011, Ljungqvist et al. 2012, Abram et al. 2013, and PAGES 2k 2013.  Know what all those papers have in common?  Their proxy analysis extends to AD 2000 and ALL show obvious hockey-sticks.

Claim: "And they continue to use Mann's "trick", splicing (questionable) thermometer data (the blue) to the proxy data. Which is simply unacceptable practice."

Response: Pure and utter BS.  First, the thermometer data has been validated numerous times.  By now the "It's UHI" bull is wearing quite thin.  Second, that list of papers I presented right above this?  None of them used Mann's "trick".  And you'd know that if you had actually read them as you claimed.  Third, you can combine multiple data sets into one analysis as long as they measure the same dependent variable.  It's called a meta-analysis, which is something I've covered before.

Claim: "Those of us who are actually scientists marvel at the inability of lay people to see what is before their eyes."

Response: I'm an all-but-dissertation Ph.D. student in forest ecology and well-versed in time-series and spatial analysis.  I'm no layperson.  Right now, I'm marveling at the ignorance you're displaying, a self-proclaimed expert who somehow shows little to no knowledge of the relevant literature and statistical techniques.

Claim: "The proxy-estimated temperature was much warmer on the 10000 year time scale, rises in the Medieval, falls in the Little Ice Age, and recovered well before human emission of CO2,"

Response:  First off, you have NO DATA that shows what you claim—unless you use a temperature reconstruction.  Second, did you even bother to examine the graph at the end?  The Marcott et al. reconstruction is the most detailed global reconstruction we have of the past 10,000 years—and it clearly shows that temperatures peaked during the Holocene Climatic Optimum then steadily declined for 5,000 years.  And yes, that decline includes the Medieval Warm Period, the Roman Warm Period, and the Minoan Warm Period.  Those "warm" periods were just minor fluctuations around the long-term cooling trend, a trend that lasted until AD 1900 when temperatures suddenly spiked upward (see also Esper et al. 2012).  And no, temperatures did NOT recover well before human CO2 emissions, unless you want to pretend that humans weren't emitting CO2 until the 20th century.


Claim: "The only thing left is the illusion that we warmer today than in the post-glacial, Minoan, Roman, or Warm Periods."

Response: See Marcott et al. (2013) and educate yourself.  You're not doing your claim of being an "expert" any favors by showing ignorance of the published literature.

Claim: "This illusion comes from splicing of different kinds of data with (as we know from the East Anglia emails) was a deliberate effort to deceive."

Response: Blatant libel and you know it.  It's no wonder you're hiding your identity, as you know full well that you could be sued for that statement.  The only deception about Climategate was in the right-wing media, as multiple investigations cleared the scientists of your implied data manipulation lie.
House of Commons Science and Technology Committee

Science Assessment Panel

 The Independent Climate Change E-mails Review

Office of Inspector General, Department of Commerce

National Science Foundation

Claim: "However, with footprints of hominids padding around England, which then had a Mediterranean-type climate, it is clear that as a matter of fact,the Earth is NOT warmer today than them."

Response:  First off, England had a Mediterranean-style climate 700,000 years ago—those footprints are at least 800,000 years old, back when England was much colder.  Second, you're again relying on anecdotal evidence of a single location and trying to pretend that one location represents the entire planet.  It does not, any more than the recent polar vortex in the US means that the entire planet is cooling off.  Third, 700,000 years ago was during the warm phase of an interglacial, warming which was driven by the Milankovitch cycles.  Today, the Milankovitch cycles have been in cooling phases for the last 6,000 years with another 23,000 years of cooling to come (Imbrie and Imbrie 1980).  So what, pray tell, is driving the current warming?  It's not the Milankovitch cycles or any other cycle that we know of.

I'll deal with your lame second comment in another post (update: Second post now online).  I think it's pretty obvious that you're no scientist, much less anyone with expertise in a climate-related field.

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