Decline in the number of climate "sceptics", reactions and new evidence

My last post showing that the number of readers of Watts Up With That and Climate Audit are declining according to Alexa (social bookmarking) has provoked some interesting reactions. A little research suggests that the response post by Tom Nelson: Too funny: As global warming and Al Gore fall off the general public's radar, cherry-pickin' warmist David Appell argues that WUWT is "Going Gently Into That Good Night", could be a boomerang and another sign of the decline. More on that and two more indications that climate change ostriches are on their way back.

Public interest in climate change

An anonymous reader had the same idea as Tom Nelson, but did not write a mocking post, but politely asked:

"how do you know it is not a general diminution of interest in climate change?".

That is naturally possible and hard to check without access to the statistics of all climate related blogs and news pages. However, as you can see below, the number of readers of SkepticalScience and RealClimate seem to be stable according to Alexa. This suggests that the decline is not general, but specific to the "sceptic" community.

The age of Climategate is almost over

It seems as if the age of Climategate is over (soon). Below you can see the number of Alexa (social bookmarking) users that visited What Up With That? At the end of 2009 you see a jump upwards. That is where Anthony Watts made his claim to fame by violating the privacy of climate scientist Phil Jones of the Climate Research Unit (CRU) and some of his colleagues.

Criminals broke into the CRU backup servers and stole and published their email correspondence. What was Phil Jones' crime? The reason why manners and constitutional rights are not important? The reason to damage his professional network? He is a climate scientist!

According to Watts and co the emails showed deliberate deception. However, there have been several investigations into Climategate, none of which found evidence of fraud or scientific misconduct. It would thus be appropriate to rename the Climategate to Scepticgate. And it is a good sign that this post-normal age is (almost) over and the number of visitors to WUWT is going back to the level before Climategate.

Since the beginning of 2012, the number of readers of WUWT is in a steady decline. It is interesting coincidence that I started commenting once in a while since February 2012. Unfortunately for the narcissistic part of my personality: correlation is not causation.

The peak in mid 2012 is Anthony Watts first failed attempt in writing a scientific study.

According to WUWT Year in review (Wordpress statistics), WUWT was viewed about 31,000,000 times in 2011 and 36,000,000 times in 2012. However, a large part of the visitors of my blog are robots and that problem is worse here as for my little read German language blog. Alexa more likely only counts real visitors.

The value of peer review for science and the press

The value of peer review keeps on producing heated debates. An interesting example was the weekend that physics professor Richard Muller wrote an op-ed in the New York Times. Some claim that Anthony Watts halted his blog for 2 days and released a scientific manuscript and an accompanying press release on the same weekend to steal attention away from Mullers op-ed. Both the op-ed and the press release were about scientific claims that had not passed peer review. Thus the Washington Post asked: Is it okay to seek publicity for a work that is not peer reviewed?

Watts et al. manuscript The eventful weekend at end of July 2012, resulted in two worthwhile blog post in the New York Times (Andrew C. Revkin at dotEarth) and the Washington Post (Jason Samenow). The manuscript was clearly released prematurely and had serious methodological problems. A few days after the press release and the blog reviews, Anthony Watts still wrote: "I’m hoping to post up a revised draft, addressing many of those comments and corrections in the next day or two." And he opened a "work page" for the manuscript, which is so quiet you can hear crickets. Just when no one expected it any more, the zombie manuscript came back from the undead; this March Watts wrote about this manuscript: "we are preparing a paper for submission". I am not a native speaking. May I ask, if you write "we are preparing", that indicates an ongoing action, right? Is there any lower limit on the intensity of this action?

The other side of the question about seeking the press before peer review is should a journalist only write about peer-reviewed studies? Further questions that came up since are: Is it unscientific to cite non-reviewed studies? Should the IPCC limit itself to reviewing only the peer-reviewed literature? Is peer review gate keeping? Is peer review necessary?

As often the context is important. What the value of peer review is, depends on who you are? An expert or not, a journalist or a newspaper reader? Another important part of the context is how controversial the finding is.

The Value of Peer Review for Science

Peer review gives an article credibility. As such peer review is "just" a filter, it does not guarantee that an article is right. Many peer-reviewed articles contain errors, many ideas outside of the peer-reviewed literature are worthwhile. However, on average the quality of peer-reviewed work is better. Thus peer-reviewed work is more likely worthy of your attention.

If you are a scientist and an idea/study is about something you are knowledgeable about there is no reason to limit yourself exclusively to peer-reviewed articles, but it is smart to prefer them. A scientist will only use peer review to preselect, because you simply cannot read and check everything. Life is short and attention a very limited resource. I also see no problem in citing studies that are not peer-reviewed, whether scientific reports or conference contributions. I do feel that by citing such studies, you give them some of your reputation, you become partially a reviewer and should read them as careful as a reviewer would.

Peer review is far from perfect. It is not intended to and cannot prevent fraud. Some bad papers will get through and some good ones will be rejected. This can be annoying for the scientists involved, but given that peer review is just a filter, it is not that bad for science in general. It is only since the second world war that peer review has become the standard. We also had scientific progress before that time.

Special issue on homogenisation of climate series

The open access Quarterly Journal of the Hungarian Meteorological Service "Időjárás" has just published a special issue on homogenization of climate records. This special issue contains eight research papers. It is an offspring of the COST Action HOME: Advances in homogenization methods of climate series: an integrated approach (COST-ES0601).

To be able to discuss eight papers, this post does not contain as much background information as usual and is aimed at people already knowledgeable about homogenization of climate networks.

Contents

Mónika Lakatos and Tamás Szentimrey: Editorial.

The editorial explains the background of this special issue: the importance of homogenisation and the COST Action HOME. Mónika and Tamás thank you very much for your efforts to organise this special issue. I think every reader will agree that it has become a valuable journal issue.

Monthly data

Ralf Lindau and Victor Venema: On the multiple breakpoint problem and the number of significant breaks in homogenization of climate records.

My article with Ralf Lindau is already discussed in a previous post on the multiple breakpoint problem.

José A. Guijarro: Climatological series shift test comparison on running windows.

Longer time series typically contain more than one inhomogeneity, but statistical tests are mostly designed to detect one break. One way to resolve this conflict is by applying these tests on short moving windows. José compares six statistical detection methods (t-test, Standard Normal Homogeneity Test (SNHT), two-phase regression (TPR), Wilcoxon-Mann-Whithney test, Durbin-Watson test and SRMD: squared relative mean difference), which are applied on running windows with a length between 1 and 5 years (12 to 60 values (months) on either side of the potential break). The smart trick of the article is that all methods are calibrated to a false alarm rate of 1% for better comparison. In this way, he can show that the t-test, SNHT and SRMD are best for this problem and almost identical. To get good detection rates, the window needs to be at least 2*3 years. As this harbours the risk of having two breaks in one window, José has decided to change his homogenization method CLIMATOL to using the semi-hierarchical scheme of SNHT instead of using windows. The methods are tested on data with just one break; it would have been interesting to also simulate the more realistic case with multiple independent breaks.

Olivier Mestre, Peter Domonkos, Franck Picard, Ingeborg Auer, Stéphane Robin, Emilie Lebarbier, Reinhard Böhm, Enric Aguilar, Jose Guijarro, Gregor Vertachnik, Matija Klan-car, Brigitte Dubuisson, and Petr Stepanek: HOMER: a homogenization software – methods and applications.

HOMER is a new homogenization method and is developed using the best methods tested on the HOME benchmark. Thus theoretically, this should be the best method currently available. Still, sometimes interactions between parts of an algorithm can lead to unexpected results. It would be great if someone would test HOMER on the HOME benchmark dataset, so that we can compare its performance with the other algorithms.

New article on the multiple breakpoint problem in homogenization

An interesting paper by Ralf Lindau and me on the multiple breakpoint problem has just appeared in a Special issue on homogenization of the open access Quarterly Journal of the Hungarian Meteorological Service "Időjárás".

Multiple break point problem

Long instrumental time series contain non-climatological changes, called inhomogeneities. For example because of relocations or due to changes in the instrumentation. To study real changes in the climate more accurately these inhomogeneities need to be detected and removed in a data processing step called homogenization; also called segmentation in statistics.

Statisticians have worked a lot on the detection of a single break point in data. However, unfortunately, long climate time series typically contain more than just one break point. There are two ad hoc methods to deal with this.

The most used method is the hierarchical one: to first detect the largest break and then to redo the detection on the two subsections, and so on until no more breaks are found or the segments become too short. A variant is the semi-hierachical method in which old detected breaks are retested and removed if no longer significant. For example, SNHT uses a semi-hierachical scheme and thus also the pairwise homogenization algorithm of NOAA, which uses SNHT for detection.

The second ad hoc method is to detect the breaks on a moving window. This window should be long enough for sensitivity, but should not be too long because that increases the chance of two breaks in the window. In the Special issue there is an article by José A. Guijarro on this method, which is used for his homogenization method CLIMATOL.

While these two ad hoc methods work reasonably, detecting all breaks simultaneously is more powerful. This can be performed as an exhaustive search of all possible combinations (used by the homogenization method MASH). With on average one break per 15 to 20 years, the number of breaks and thus combinations can get very large. Modern homogenization methods consequently use an optimization method called dynamic programming (used by the homogenization methods PRODIGE, ACMANT and HOMER).

All the mentioned homogenization methods have been compared with each other on a realistic benchmark dataset by the COST Action HOME. In the corresponding article (Venema et al., 2012) you can find references to all the mentioned methods. The results of this benchmarking showed that multiple breakpoint methods were clearly the best. However, this is not only because of the elegant solution to the multiple breakpoint problem, these methods also had other advantages.

Could we get more Earthquakes due to global warming and thermal expansion of the Earth's crust?

Thermal expansion can release quite some force as is seen in bridges and railroad tracks that are deformed due to hot weather. I am wondering whether thermal expansion of the Earth's crust due to global warming can similarly lead to seismic activity, especially at subduction zones where one crustal plate slides under another one.

I have searched the scientific literature, but was unable to find any articles on the topic, while it sounds quite straight forward to me. Did really no one have this idea before, or was it already debunked in 1960?

Dear journalists, This is not a press release; I do not like science by press release. While I am a scientist, I have no special expertise in geology. Please only write about this if the standards of your publisher are so low that you would also write about it if you next-door neighbour would have this idea. In other words, please wait until there is a scientific publication on this. Even better would be to wait until there are several papers, but I realise that that is illusory. Dear "skeptics", I did not write that your SUV is responsible for the seismic atomic genocide of the the Japanese population. This post is only written to bring the idea under the attention of the right scientists. At this stage, it is very likely that the idea is wrong and that nothing will happen. Dear colleagues, the reason to write this post is to attend someone with the skills to investigate it. It is thus highly appreciated if you could forward it to someone who may have the right skills. I guess two skills are needed: 1) modelling of the warming of the crust and 2) dynamical modelling of the crust expansion. If you have one of these skills, please contact me, maybe someone with the second skill also responded. If you have both skills or know someone, feel free to act as if it is your own idea. Ideas are cheap and this back-of-the-envelope computation was quickly made. The real innovative step is deciding which idea is worth spending a year of your time on to make it into science. It would be nice if after publication you could act as if a colleague attended you to this post and send me a copy of the article. I am curious.

Back-of-the-envelope computation

The length of the Equator is roughly 40x10⁶ metres. And my high-school tables book gives thermal expansion coefficients for various stone types between 4 and 12x10^-6 K^-1. So for a one degree temperature change one would expect that the Earth's crust would expand by 160 to 480 metre. (More accurately, one would use the size of a plate not the circumference of the Earth. On the other hand, the projected temperature change is larger than one degree.) For the sake of the argument, let's say that it is about 100m. One thing I do not know is whether the crust is sufficiently brittle/solid (like a railway track or bridge that deforms by heat) or whether there are air and liquid pockets and cracks which could absorb the expansion. Furthermore, maybe the additional pressure would mainly increase the width of the crust not its length or the crust would just crumple a little more.

A database with daily climate data for more reliable studies of changes in extreme weather

In summary:

• We want to build a global database of parallel measurements: observations of the same climatic parameter made independently at the same site
• This will help research in many fields
• Studies of how inhomogeneities affect the behaviour of daily data (variability and extreme weather)
• Improvement of daily homogenisation algorithms
• Improvement of robust daily climate data for analysis
• Please help us to develop such a dataset

Introduction

One way to study the influence of changes in measurement techniques is by making simultaneous measurements with historical and current instruments, procedures or screens. This picture shows three meteorological shelters next to each other in Murcia (Spain). The rightmost shelter is a replica of the Montsouri screen, in use in Spain and many European countries in the late 19th century and early 20th century. In the middle, Stevenson screen equipped with automatic sensors. Leftmost, Stevenson screen equipped with conventional meteorological instruments. Picture: Project SCREEN, Center for Climate Change, Universitat Rovira i Virgili, Spain.

We intend to build a database with parallel measurements to study non-climatic changes in the climate record. This is especially important for studies on weather extremes where the distribution of the daily data employed must not be affected by non-climatic changes.

There are many parallel measurements from numerous previous studies analysing the influence of different measurement set-ups on average quantities, especially average annual and monthly temperature. Increasingly, changes in the distribution of daily and sub-daily values are also being investigated (Auchmann and Bönnimann, 2012; Brandsma and Van der Meulen, 2008; Böhm et al., 2010; Brunet et al., 2010; Perry et al., 2006; Trewin, 2012; Van der Meulen and Brandsma, 2008). However, the number of such studies is still limited, while the number of questions that can and need to be answered are much larger for daily data.

Unfortunately, the current common practice is not to share parallel measurements and the analyses have thus been limited to smaller national or regional datasets, in most cases simply to a single station with multiple measurement set-ups. Consequently there is a pressing need for a large global database of parallel measurements on a daily or sub-daily scale.

Also datasets from pairs of nearby stations, while officially not parallel measurements, are interesting to study the influence of relocations. Especially, typical types of relocations, such as the relocation of weather stations from urban areas to airports, could be studied this way. In addition, the influence of urbanization can be studied on pairs of nearby stations.

The social dimension of health

Maybe I could even have title this post: the social dimension of life.

Many people seem to interpret "survival of the fittest" as relating to the fitness studio. While the fittest are simply those who survived. Whether you survive depends on lot on your tribe and only partially on your self, if you do not behave too stupidly.

Frank Forencich speaking at the Ancestral Health Symposium, 2012, explains this social part of health and a full life.


Frank Forencich is blogging at The Exuberant Animal and is a refreshing sound in the paleo world. His posts are thought provoking and well worth reading.