Sunday 20 June 2010

IPCC Technical Assessment Report 5 – Thesis 3

Thesis: The presentation of sea ice in TAR4 used only a sub-set of the data. It should use a wider range of data with reference both to data which were available at the time of TAR4, and data which have become available since.

The technical summary presents the following set of graphs:

 

The way the graphs are presented is reminiscent of graphs of return on investment of rivals presented by some of the less honest financial intermediaries.  Those for the Arctic are presented as anomalies with a scale set so that the full range fits in the rectangle and it seems as if ice extent has fallen close to zero. For the Antarctic, where the area of ice has been tending to increase, they have used the same scale which conveniently minimises the increasing tendency of Antarctic ice.

The following graph presents the same data, updated to May 2010, but as extent not anomalies.



This very clearly shows that on average there are similar areas of sea ice in the Arctic and Antarctic, that the variation is much larger in the Antarctic than the Arctic and the loss of sea ice in the Arctic is only partially balanced by the gain in the Antarctic.  A linear regression through the average values suggests that the Arctic has lost 50,000 km2 per year whereas the Antarctic has gained 14,000 km2 per year. The average total area of sea ice 23.9 million km2 so this loss represents a rate of 0.15% a year.

The Synthesis Report also mentions the break-up of the Larsen B ice shelf.  This was an area of ice partly floating and partly resting on land and joined to the main Antarctic ice shelf. It was located on the most northerly (i.e. warmest) point of the Antarctic. The area of the ice shelf was 3250 km2 and its weight was 72 billion tons. The loss of the ice shelf has become iconic and it has been compared to the area of Rhode Island or to the trillions of 20 lb bags which could be filled (though not in the IPCC report).  In relation to the area of the Antarctic ice sheet it represents only 0.02% of the area or 0.003% of the volume.

We do recognise that the minimum area of sea ice is a useful metric. The albedo (reflectivity) of ice is high and that of sea water is low. In summer, when ice is at a minimum and sunlight at a maximum, the albedo effect is important and the fears that the low Arctic minimum of 2007 could lead to a progressive reduction in sea ice area were valid.

At the time of the TAR4 there was little information available on ice depth and volume. From October 1998 daily values of ice thickness are available from the US Navy polar ice prediction system(PIPS). The forecast values of ice thickness use weather forecasts, and buoys and ice concentration data from the Special Sensor Microwave Image (SSM/I) are used to initialize the system's forecast. The results are available as GIF images. A typical one is given below.


To derive areas and volumes the graphic images were downloaded analysed.  The projection used is not an equal area project so the areas derived were approximate. They were based pro-rata on a scanned image of Greenland. During the analysis it was found that the colours representing thickness range 0.5 to 0.75 were never present. It should also be noted that occasionally there were anomalous values, for example for a few days the Caspian and Aral seas were included.

The following graph shows the area and volume of sea ice from October 1998 to May 2010. These figures only apply for ice greater than 0.75 m thick and consequently the areas are less than those of ice extent in the above graph.



 In general the volume and area show similar variation but after the low summer minimum of 2007 the ice area recovered well in 2008 but the volume. This is reflected in the chart on ice thickness.


This shows that minimum ice thickness was less in 2008 than in 2007, giving some support to those who said the ice that year was “rotten”. It is interesting to note that the ice thickness is bi-modal; one maximum occurs in May when the ice area has just passed its maximum and the second in September near to the point when it is at its minimum. This can be seen more clearly in the following graph where compare average thickness with current ice thickness.

The shape of the graph suggests that ice thickness is belatedly reaching its spring maximum. How it will develop in the coming months is something we will follow with interest. What these graphs do show is that Arctic sea ice is recovering in terms of volume, are and thickness.



In these “theses” we generally do not concern ourselves with short term effects so to counter that remember that during the last inter-glacial sea levels were 6 m higher than at present.  Although melting sea ice does not affect sea levels we can none-the-less expect more melt independent of any anthropogenic effect. 

IPCC TAR5: The presentation of graphs data in TAR5 was biased to give an exaggerated impression of ice loss. In TAR5 the presentation should be more balanced. It should use a wider range of metrics to assess changes in sea ice.

Tuesday 18 May 2010

IPCC Technical Assessment Report 5 – Thesis 2

Thesis: That the discussion of sea level rise in IPCC TAR4 has much to recommend as a model for other topics.

Those of you who have already seen our first thesis, on global temperatures, may have got the impression that we were out to ‘get’ the IPCC. This is not the case. We are self-financed and have no agenda. As we say on our Home Page: “We are trying to prove only one thing: rational debate is possible when participants have access to the facts.”

In TAR4 the increase in sea level is presented in the following graph.


This graph appears as Figure 3 in the Summary for Policy Makers and elsewhere (We have extracted the sea levels from a compound graph which also showed Global Average Temperatures and Northern Hemisphere snow cover). It combines levels from tide gauges (circular dots) and satellite measurements (the red line).

In the summary the accompanying text says: “Global average sea level rose at an average rate of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003. The rate was faster over 1993 to 2003: about 3.1 [2.4 to 3.8] mm per year. Whether the faster rate for 1993 to 2003 reflects decadal variability or an increase in the longer term trend is unclear.” Similar words appear in the Technical Summary and the Synthesis report. What is commendable in this case is that even in the condensed Summary for Policy Makers there is no attempt to attach a high level of significance to the higher rate of sea level rise for the ten years preceding the preparation of the report.

The Technical Summary also states (Paragraph 3.3.3): “The tide gauge record indicates that faster rates similar to that observed in 1993 to 2003 have occurred in other decades since 1950.” This is supported by the following figure in Chapter 5 of the main report.


This contrasts markedly to the global temperature graph we discussed in the previous ‘thesis’. (http://www.climatedata.info/Discussions/Discussions/opinions.php?id=5404421343497121129 ).

There are two areas where the increase could be presented in a wider context in TAR5.

Firstly since TAR4 was written there is more evidence of sea level changes in the last couple of thousand years.


The blue crosses represent relative sea level rise for Vidarholmi in Iceland as calculated by Gehrels et al. No adjustment has been made for post glacial rebound but this is unlikely to have varied substantially over the period of the estimates. The figure before 100 AD may have been modified by compression in the salt marsh sampling area but even so the levels after that date suggest that recent rates of rise are by no means extraordinary.

The green circles show estimates of sea level on the coast of Israel calculated by Sivan and Toker. They are based on archaeological evidence from different broadly defined time periods (e.g. Hellenic or Crusader). The dating and levels are not given to a high degree of accuracy but also suggest that rapid sea level changes might have occurred in the past.

The red line, provided for comparison, is the increase since 1702 based on tide gauges by Jevrejeva et al. This confirms that the rate of sea level increase accelerated around 200 years ago and is not a recent phenomenon.

The second point is that in the previous interglacial sea levels were about 6 m higher than they are today and in other interglacial periods levels were from 3 m to 20 m higher. It is therefore possible than in coming centuries many coastal locations on earth might experience sea level rises of the same order of magnitude as those estimated by Sivan and Toker. That said there are many coastal cities in the world, such as Marseilles, Akko (Acre) and Naples, which existed well before the start of the present era and which have adapted to sea level changes.

IPCC TAR5: The TAR4 dealt with sea level changes accurately and in a responsible way. However the IPCC TAR5 could be improved by expanding information on the context of the projected level changes.

References:
Gehrels et al., Rapid sea-level rise in the North Atlantic Ocean since the first half of the nineteenth century. The Holocene 2006; 16; 949

Shivan and Toker, The Sea’s ups and downs. http://newmedia-eng.haifa.ac.il/?p=2330

Jevrejeva, S., J.C. Moore, A. Grinsted and P.L. Woodworth. 2008. Recent global sea level acceleration started over 200 years ago?, Geophysical Research Letters, 35

Wednesday 12 May 2010

IPCC Technical Assessment Report 5 – Introduction

At the start of 2010 the IPCC attracted a lot of criticism for three projected climate change impacts which were poorly supported. These were that Himalayan glaciers might disappear by 2035, that African agricultural yields could fall by 50% and that 40% of the Amazonian rain-forest could react drastically to changes in precipitation. In each case the source of the claim was speculative and lacking sound evidence. The IPCC’s response was that in such a major series of documents it was well nigh impossible to avoid a few mistakes. To some extent this is true but the fact the errors all erred on the side of exaggerating the effects of climate change says much about the IPCC’s lack of balance.

We believe however that there are more serious criticisms which can be leveled against the IPCC.

Science is only as good as its data and in many cases the data presented by the IPCC tell only part of the story.

Since we are criticising the IPCC we should make out own position clear. So where do we stand? We believe that the science and data show unequivocally that temperatures today are higher than would have been case were it not for greenhouse gases emitted by human activity. On the other hand we do not believe that the more extreme forecasts of increased temperatures and their impact have been proven. We also believe that there are good reasons for reducing use of fossil fuels, of which effect on the climate is but one.

We also believe that climate modelling is important for the future. In the past, design of anything affected by weather, urban drainage or water supply for example, has been based on a statistical analysis of past data. It is now clear that a fundamental assumption of such analysis, that the events analysed are independent of each other, is invalid. To be able to predict natural and anthropogenic changes in climate should become the new paradigm for engineering design.

Our position, and that of those who have studied the science and share our views, is similar to that of Martin Luther, the 15th century reformer. He was, and remained all his life, a Christian but he thought that the activities and excesses of the Roman Catholic Church at that time were acting against the faith he accepted. We believe that there is a powerful analogy with the IPCC at the present time. Its performance is such that far from leading the population to accept their assertion that unless radical and immediate action is taking the world will suffer gravely they, by bias and distortion in their arguments, have left many people refusing to accept that humans have any influence on the climate.

Martin Luther put his case by pinning 95 Theses to the door of a church (today he would probably have been a blogger). What we are going to do is to publish a series of ‘theses’ where we highlight some aspects of the IPCC Technical Assessment Report of 2007 (TAR4) which could be improved in the next report (TAR5).

There remains one important question: Why should you believe us? The answer is you won’t have to. For reach of our theses we will give chapter and verse on the section of IPCC TAR4 we are commenting on and the source of the data we use to propose improvements.

Friday 9 April 2010

Ian McEwan: Solar

This book has two features which differentiate it from the other books reviewed here: it is a novel and relatively unbiased on the topic of climate change.

Ian McEwan is one of Britain’s leading novelists. In interviews he says that he accepts the scientific view that climate change is taking place as a result of human activity. Some newspapers also reported that he had delayed publication of ‘Solar’ until after the Framework Convention on Climate Change Meeting in Copenhagen. From what I had read of his earlier novels I was expecting this novel to contain much wailing and gnashing of teeth but I was wrong. On the author’s web site the novel is described as “an engrossing and satirical novel which focuses on climate change”. I agree with that.

The main character, Michael Beard, won a Nobel Prize in Physics as a young man but he is now in his 50s treading water intellectually and trading on his reputation. He gives lectures and decorates various committees. Despite his unprepossessing appearance, baldness and excessive girth he is a serial husband and philanderer.

One of his appointments is as the one-day-week, figure-head, chief of a government initiative to tackle global warming. Initially showing only lukewarm interest in his sinecure, a combination of circumstances leads him to an awareness that photo-electrical interactions, his own area of expertise, could provide the ideal solution to clean, cheap, carbon-free energy. The book has a few factoids, which I have not checked, which underline his idea. A kilogram of gasoline contains 13,000 watt hours of electricity but the best batteries only store 300 watts hours per kilo. In other words, alternative energy sources have to compete with gasoline’s weight/energy ratio and avoid electrical storage. The third factoid is that the hydrogen in one litre of water has three times the energy of a litre of gasoline. Since hydrogen can be stored, unlocking it from water could provide the ideal clean source.

His route to this realisation is not straightforward. He is invited to join a group of artists concerned with climate change in a ship north (but only just) of the Arctic Circle which he is assured will be “toastily-heated”. One of the book’s great comic moments is when outside of the ship he stops to satisfy the needs of nature and discovers that at very low temperatures flesh sticks to metal zips. The irony of living in comfort, building ice-sculptures and riding snowmobiles to see vanishing glaciers as a protest against climate change is not lost on him.

While head of the government alternative energy centre, Beard decides to back a helical wind turbine for use on the roofs of private homes. The initial enthusiasm is soon worn down by health-and-safety concerns, current conversion and other problems which take teams of well-meaning but unproductive experts to examine in long and expensive detail.

As Beard's disorganised personal life impacts on his professional life, the invitations to lecture and to sit on boards become fewer and fewer. He starts to develop the idea of clean energy from water. To get development money he delivers a speech that Al Gore would be proud to a convention of investment bankers.

When the idea is getting closer to realisation, his business partner, whose seen a woman professor of atmospheric studies on television saying it is getting cooler, starts to wonder if people will still be willing to pay for alternative energy sources. Beard reassures his partner by saying :

'Here’s the good news. The UN estimates that already a third of a million people a year are dying from climate change. Bangladesh is going down because the oceans are warming and expanding and rising. There’s drought in the Amazonian rainforest. Methane is pouring out of the Siberian permafrost. There’s a meltdown under the Greenland ice sheet that no one really wants to talk about. Amateur yachtsmen have been sailing the North-West Passage. Two years ago we lost forty per cent of the Arctic summer ice. Now the eastern Antarctic is going… It’s a catastrophe. Relax!’



Remember, the author accepts that anthropogenic climate change is taking place yet here he is lampooning the tendency of ‘warmists’, to revel in bad news. The ‘deniers’ are no better; they are never happier than when airports are closed by snow storms and motorists are trapped by blizzards.

Despite the author’s beliefs he has the perspicacity to see participants from both sides, warts and all, in a clear objective way; if only those who write technical books on climate change were as perceptive about the science.

Author: Ian McEwan

Publisher: Jonathon Cape, 2010

ISBN: 9780224090490

Saturday 3 April 2010

Is Google biased in favour of climate change?

Google ranks pages from 0 to 10 using a page rank (named after Lawrence Page). The higher the rank the more likely is Google to send an enquiry to that page. Sites with the maximum rank of 10 include CNN.com and BBC.co.uk.

About a year ago my colleague and I set up links to the most popular climate change blogs, those with a Google page rank of 5 or above. We’ve just revisited the blogs and found that whilst changes to ‘non-sceptic’ blogs are fairly neutral (as many upgraded as downgraded) for ‘sceptic’ blogs there have been more downgrades than upgrades. The following table summarises the situation.

Site type Change Number
Non-sceptic +1 9
Non-sceptic 0 23
Non-sceptic -1 7
Non-sceptic -2 1
Sceptic +1 2
Sceptic 0 25
Sceptic -1 10
Sceptic -2 3

The non-sceptic blogs are almost in balance with 9 up and 8 down; one has dropped by 2 places but that blog has only posted once since early December 2009. On the other hand only 2 sceptic blogs have increased but 13 of them have fallen, three of them by two points. Unlike the non-sceptic blog which fell by 2 points all three of the sceptic blogs which fell by 2 points had posted something new in the last few days, though one of them had moved its web site to a new address.

It cannot be a function of number of visitors. Alexa, the web information company, gives “Watts up with that” as the most popular climate blog and it has a page rank of 7. On the other hand “Realclimate” according to Alexa has had a quarter of the visitors to ‘Watts’ over the last 3 months but has a page rank of 8. “ClimateAudit”, which also has more visitors than “RealClimate” also has a page rank of 7.

There are also several non-sceptic sites which get less than one percent of the visitors of ‘Watts’ but have the same rank of 7.

The conclusion, unlikely as it may seem, is that Google does have a bias – against climate sceptics.

Postscript
As several people have pointed out on blogs where we have linked to this, and we ourselves were aware, Google's ranking system is complex, secret and changing. None-the-less it does seem strange that at a time when opinion polls suggests that sceptics are in the ascendant there should be a diminution in the their Google rankings.

Wednesday 31 March 2010

A. W. Montford: The Hockey Stick Illusion

If you’ve found this review you probably know the story but basically it is this. Temperatures before the middle of the 19th century can only be estimated indirectly from proxies: physically measurable characteristics of plants or animals which lived at earlier times and which respond to temperature changes. In 1999 a young climate researcher, Michael Mann, and colleagues published a paper in Nature which suggested that temperatures at the end of the 20th century were higher than at any time in the previous 600 years. The graph of this, shaped like an ice-hockey stick, became iconic and appeared several times in the IPCC 2001 technical assessment report and elsewhere. In 2002 a retired mining engineer, Steve McIntyre, became suspicious of the fact that the paper both contradicted conventional wisdom and gave an ideal message for climate change activists that he started to investigate. His findings led to Congress setting up to two high level technical enquiries and a congressional committee held hearings.

Those of you who have seen my review of ‘Dire Predictions’ by Mann and Kump might imagine that I would automatically give a favourable review to this book. After all it is the very antithesis of the view of climate by IPCC insiders like Mann and Kump. But that is not how we work at climatedata.info. We try, as far as possible, to avoid polemics for polemics sake and let the data speak for themselves.

The author of this book, Andrew Montford, is a blogger who uses the pseudonym ‘Bishop Hill’. He started off as a political blogger and has a Bill of Rights for the UK on his site.  The Bill of Rights shows that he is of a libertarian disposition and is therefore not predisposed to accept the restrictions which would be necessary to bring about a major reduction in carbon emissions. He admits in the book that his site only took off when he started blogging on climate the ‘Hockey Stick’.

The book reads well, is well referenced, and appears to be a crushing indictment of the IPCC and the paleoclimatologists who developed the ‘Hockey Stick’. To the author, Steve McIntyre is definitely one of the ‘good guys’ and beyond reproach. Whilst it tries to present arguments from both sides there is no doubt that the book is very partisan.

In referring to the meeting to discuss the ‘Hockey Stick’ by the National Academy of Sciences in the USA he discusses the response of Michel Mann to a question concerning verification of the calculations. In a published paper Mann had reported that he had calculated a particular statistic (r squared). In the book he is quoted as telling the meeting “We didn’t calculate it. That would be silly and incorrect reasoning.” I have Googled those phrases and the only source I can find is Steve McIntyre’s blog at climateaudit.org which is the source referenced by the author. There appears to be no transcript of the NAS meeting, at least I could not find one online. I have also studied the transcript, and listened to much of the recording, of the subsequent congressional hearing and can find no evidence to support what is claimed to have been said at the NAS meeting. My attempts to get to the bottom of this do not prove or disprove what has been claimed but to make such a serious charge without independent  verification is a clear example of bias.

Throughout the book frequent reference is made to scientists withholding data and there is always the assumption that if data is withheld there are nefarious reasons for it. One of McIntyre’s complaints was that Bristlecone Pine trees were central to calculation of the ‘hockey stick’ but that the data from the trees stopped in 1980, just as the main warming started. He therefore set about visiting the site to resample the trees. This was done and the cores were re-analysed. I have tried to access the data using the links on his site including http://climateaudit.org/data/colorado/SMCD.dat but the links are dead. In a footnote in the book the author says [McIntyre] “has yet to publish the findings in a journal.” I am not assuming there is anything sinister in this but the fact that the author so glibly accepts the lack of openness from McIntyre but assumes ill-intent from others is a further demonstration of his bias.

Enough of the polemics: where does this leave the science?

Climate scientists are under pressure from politicians to present a clear picture. There is no dispute about the fact that many climate scientists felt that if temperatures had been warmer in the historic past than the present this would dilute the message they could deliver to the politicians. When a climate scientist appeared to be able to prove that current temperatures were indeed higher than in the past millennium they jumped at it as way of getting their message across. The ‘Hockey Stick’ became the star of the 2001 IPCC report.  However my feeling is that on balance the climate science community regrets the prominence given to the hockey stick. There are two reasons for this.

Firstly the aim of the IPCC is to convince the public of the necessity to take action on climate change. The use of temperature proxies has been so well discussed that many well informed citizens are aware of the need to ‘hide the decline’ or believe that everything is based on a few trees in Siberia. The ‘decline’ refers to the fact that in recent decades trees in  the northern hemisphere are not responding to temperature increases in the way they were assumed to; this brings into question the accuracy of long-term temperature estimate based on tree rings. Many people also believe that scientists have ‘cherry-picked’ the trees, the Yamal series from Siberia, that give the answer they want.  This was one of McIntyre’s first criticisms of Mann, that his method selected proxies that gave a ‘hockey stick’. Many scientists now would agree that temperatures in the medieval period were similar today but the science is not accurate enough to be able to say whether they were slightly warmer or cooler.

In an attempt to support the ‘hockey stick’ some climate scientists, including Mann and Kump in their book, say they accept that in parts of the world the medieval period was warm but the warming was less general than today. This argument is a bit disingenuous. In those parts of the world where written records of the medieval period exist there is evidence that medieval temperatures were high but of course not all parts of the world have written records of that period. So the argument comes down this; one side says “warming only occurred in parts of the world with written records”, and implies it did not elsewhere and the other side says “warming occurred in all parts of the world with written records” and implies that it did elsewhere.

Secondly, the question of past temperatures does not of itself determine whether or not anthropogenic warming is taking place. The temperature could be rising as a result of human action now even if temperature in the past were higher than today. Where it is critical is in discussing the impacts. If temperatures had been 2 °C higher in the past it is difficult to argue that a rise of that order of magnitude would be catastrophic.

From reading his blog I have always felt that Steve McIntyre viewed his role as scientific and he has made many attempts to reach out to the scientific community. Andrew Montford definitely has a political agenda and would probably be sceptical about climate change whatever the science said. I am not sure that McIntyre is well served by this book.

Author: A. W. Montford
Publisher: Stacy International, 2010
ISBN: 978 1 906768 35 5

Thursday 25 March 2010

Michael Mann and Lee Kump: Dire Predictions – Understanding Global Warming

The Reader’s Digest magazine used to publish what they referred to as “unexpurgated abridgements.” By this they meant that they had left in the exiting bits and cut out the boring bits. This book could be considered an “unexpurgated abridgement” of the IPCC 2004 Technical Assessment Report. A lot of the detailed science has been left out but the elevated temperatures and other symptoms associated with an attack of ‘dire era’ are given lurid prominence.

The book does give a clear and approachable synopsis of how our climate operates and how human activity can lead to changes. As an introduction to the science, the book is quite good. It is clearly written and has good supporting material. It also tackles some of the issues raised by sceptics.

In a recent double interview in Discover magazine with Judith Curry and Michael Mann, Judith Curry drew a nice distinction between ‘political sceptics’, who do not want climate change to be true, and ‘scientific sceptics’, whose opinions are based on the evidence. I would suggest that there is a third type of sceptic: the ‘bar-room’ sceptic, who’s not reticent about sharing his knowledge over the internet. You know the type “Why does the IPCC ignore the book ‘The incredible lightness of being’ by the Russian Milan Kovich which proves CATEGORICALLY that the recent so-called warming has all been due to fluctuations in the earth’s orbit?”  Unfortunately the authors tend to engage with this level of sceptic rather than the scientific sceptics. The issues where there is real scientific debate, the ‘hockey-stick’ and the urban heat island effect are either ignored or glossed over. Instead they rebut claims that the increase in CO2 is due to natural fluctuations, which scientific sceptics generally accept, or raise the hoary chestnut of “In the 70s the scientists said we were in for global cooling so why should we believe them now?”

The way they tackle the cooling/warming issue says a lot about the authors’ scientific credibility. They present a pair of graphs (page 45 in my edition) which show that the northern hemisphere temperature fell from 1940 to 1970, which explained the then current belief in cooling, and then again increased. Like the rest of their graphs there is no reference to the source but as it starts in 1850, and only the CRU record started in that year, it is reasonable to assume that that was the source.  Yet their graph is very different to the CRU one: they show temperatures rising from 1970 to the present by 1.8 °C but the CRU data shows a rise of less than half of that. Elsewhere (pages 20 and 88 in my edition) they show graphs of ‘past observed surface temperature changes’ with an almost constant rate of temperature rise and no sign of the 1940 to 1970 fall. This is very different to the above graph. Since the observed global temperature record shows similar variation to the northern hemisphere record that does not explain the anomaly. Once again without references it is difficult to be definitive but it is almost certainly the ‘modelled’ temperature increase which they have presented as ‘observed’. This gives the false impression that the temperature increases projected by the models follow on naturally from steadily rising observed temperatures.

The book is in fact heavy on dire predictions, based on model projections, but very light on evidence that the models were able to represent past changes accurately. For example, they talk of precipitation changes as being probably of ‘more importance than temperature changes’ but present not a shred of evidence of how well models simulated precipitation.  At least the IPCC report does have a shred of evidence: a graph which occupies 1/8 of a page!

What is most frustrating is the fact that this biased, one-sided, presentation of the facts is counter-productive. I fully accept that people are in part responsible for the recent temperature increase. I fully accept that there are many reasons, one of which is CO2 emissions, for reducing fossil fuel consumption. I fully accept that climate projections should play a major role in how we plan for the future. Yet, largely because the IPCC and scientists chose to ignore Abraham Lincoln’s dictum and think that in this ‘information age’ they can ‘fool all of the people all of the time’, the number of climate change sceptics is currently growing.

To give a final example: in his book “Cool It” Bjorn Lomborg mentions the 35,000 people killed in a heat wave in Europe. He also mentions that many more people die of cold in winter and follows it with a nuanced discussion of age profiles and the difficult moral question of how you balance the deaths of old people and of children. In this book only the heat deaths are mentioned. If you are an intelligent, thoughtful, person which approach is most likely to help form your opinion?

I also noticed a typo on the back cover where the book is described as being a scientifically ‘based’ overview. And where, you might ask, is the typo? It’s the missing “i” of course? 

Authors: Michael Mann and Lee Kump
Publisher: Dorling Kindersley, 2008
ISBN: 978-0-7566-3995-2

Saturday 6 March 2010

Archer and Rahmstorf: The Climate Crisis - An introductory guide to climate change

“I feel that it is important to not let bad, politically motivated science stand unchallenged.“ This is a quote we could all agree with and is part of the motivation behind our site. Only too often both ‘deniers’ and ‘warmists’ select a sub-set of the available science and then push it beyond reasonable limits to further their cause. Our mission is to sort out the justifiable from the bogus.

The authors of this book are, to use the current term, ‘warmists’. Their book is based largely on the IPCC 2007 assessment report which both of them contributed to. To their credit the authors have managed to avoid some of the recent brick-bats thrown at the IPCC. They do not repeat the scientifically dubious claims regarding Himalayan glaciers, African agriculture or the Amazonian rain forest. What is more they found no space in their book for any reference to Dr Pachauri, Chairman of the IPCC, whose commercialisation of the IPCC in the interest of organisations he is associated with has attracted much opprobrium. That said, there is a lot of politically motivated science in their book.

One of the most egregious examples of trying to gull the gullible is in their figure 3.1, reproduced below:

This purports to show that the linear trend of temperature increase is accelerating but is completely spurious for two reasons. Firstly, given that temperatures have been both rising and falling, there will always be short periods when the rate of rise is higher than the long-term average. Secondly, the 25-year rate of rise around the period 1910 to 1945 is almost the same as the 25-year period they show at the end of the record. The authors repeat their claim in the chapter summary: “Measurements unequivocally show that we are in are in the midst of an accelerating global warming”. They are wrong: there is no evidence that the rate of temperature increase is accelerating. [Postscript. The authors attribute this figure to the IPCC TAR4 Summary for Policy Makers figure 3, which does have a plot of temperatures, and I assumed they had added the rate of temperature rise. In fact the figure comes directly from the IPCC Technical Summary figure 6. So, I apologise to the authors for trying to hoodwink the public; they themselves had been hoodwinked by the IPCC.]

The authors do something similar with sea level rise. They state (correctly) that the rate of rise over the 20th century estimated from tide gauges averaged 1.7 mm/year. They also state that, in 2003 when the IPCC report was prepared, satellites had been showing a rate of increase since 1993 of 3.4 mm/year (also correct). They conclude that this indicates ‘the sea level rise has accelerated in recent decades.’ What they do not tell us, though Rahmstorf as a Professor of the Physics of the Oceans must have known, is that the rate of level rise has fluctuated and a rate of 3.4 mm/year was not unknown in the past. What they also should also have known, since their book was published in 2010, is that for the last few years the rate of rise estimated by the satellites has hovered around the long term rate of 1.7 mm/year. Again the facts show their science is politically motivated.

The book is well produced with colour photos and graphs. The use of colour seems sometimes to be at the expense of the science. The statement “in many parts of the world, the fraction of the total annual rainfall that comes down on just a few very wet ways has increased” refers to figure 3.6. Rather than a graph supporting this assertion we get a photo of bus driving through about 20 cm of water. Another example of a disconnect between the text and the cited figure relates to tropical cyclones. They quote the IPCC report as saying there is “no trend in the total number [of tropical cyclones] that occur each year” then show a graph of Tropical Cyclone counts. This graph incidentally has 4 lines, only 3 of which are referenced in the key. In relation to hurricanes the other claim they make, that ‘trends since the 1970s [are] towards more intense and longer-lasting cyclones’, may be true but ignores the fact the estimates of cyclone energy since 1851 show periods of rising energy, 1860 to 1890 and 1920 to 1950, similar to that from 1970 to 2005. The Energy Index for 2009 was actually below the average in the 1970s. The authors could not, of course have known that particular fact at the time of writing, but quoting short-term trends as evidence of long-term climate change carries the risk that a reversal of the short-term trend appears to invalidate the argument. I use the word “appears” advisably; in reality short-term trends in a system with as many “random jitters” (their phrase) as our climate say next to nothing either away about long-term changes.

One might expect the author of the quote at the head of my review to applaud my efforts to debunk politically motivated science. It won’t happen. The quote is from an email sent by Stefan Rahmstorf himself.

Authors: David Archer and Stefan Rahmstorf
Cambridge University Press, 2010
ISBN: 978-0-521-73255-0

Tuesday 16 February 2010

Sceptics Now Welcome

Over the last few months there has been a remarkable change of tone among the climate science community. Until recently sceptics were treated as barely worth the consideration of ‘real’ climate scientists. The CRU emails showed clearly how attempts were made to prevent the publication of any paper questioning climate orthodoxy or, should such a paper have been published, to prevent it appearing in any IPCC publication. That has now changed; or at least the rhetoric has changed; only time will tell if the underlying philosophy has changed.

One sign of this was a recent article in a national newspaper by the UK government’s Chief Scientist, John Beddington. In the article he says “The impact of global warming has been exaggerated by some scientists and there is an urgent need for more honest disclosure of the uncertainty of predictions about the rate of climate change.” Not to be outdone his predecessor, David King, has weighed in with an article which makes a similar point.

This is in marked contrast to a statement by the same David King in 2004, who was still at the time in post, that climate change was a bigger threat than terrorism. Not much sign of scientific openness there.

The discussion of the CRU emails, when they got through to the main stream media, was probably the first time many of the public were aware of any dissention regarding the inevitability and magnitude of climate change. In this atmosphere of heightened awareness we have had ‘Glaciergate’, ‘Amazongate’ and now “Africagate”.
The first of these, Glaciergate, related to claims in an official IPCC report that glaciers in the Himalayas could disappear by the year 2035. The claim was based on speculation by an Indian scientist in an interview with the New Scientist, a British popular science magazine. This claim was included in a report by the WWF which was quoted by the IPCC as a reference. Although a number of comments were made during the draft stage of the IPCC report it was not removed. Initially the IPCC tried to defend the claim. Dr Pachauri the chairman of the IPCC said criticism was based on ‘voodoo science’. However the IPCC has now accepted that the claim was without justification.

Amazongate refers to a claim in another IPCC report that “up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation". As a source the IPCC again referred to a WWF/IUCN publication on forest fires. This time the WWF publication did give a reference – to a publication in the highly respected science journal “Nature.” That article was titled “Large-scale Impoverishment of Amazonian Forests by Logging and Fire”. In it there is a reference to 40% but it is to selective logging which leaves the remaining forest vulnerable to fire. There is a separate reference to sensitivity to drought during El Nino events. So again, the IPCC claim is not substantiated.

The third of these claims relates to African agriculture. IPCC has claimed that in some African countries, yields from rain-fed agriculture could be reduced by up to 50 percent by 2020. Whereas the other two claims in were in specific sections of the main body of the report, this claim appears in the synthesis report which highlights the most important issues. Dr Pachauri was himself a contributor to this report and has quoted the claim on many occasions. As with the other claims a report from an advocacy group is given as source and tracing the references back reveals a different picture to that presented in the IPCC report. The report was based on submissions to the IPCC from three countries: Algeria, Tunisia and Morocco. Only one of these uses the figure of 50% relating it specifically to grain yields in drought years with a lesser reduction in other years. So from a statement relating to one country and one crop under specific conditions the IPCC has produced a statement which appears to have implications for all rain-fed crops for the whole of Africa.
These three specious claims were revealed by sceptics not by the IPCCS internal review system. No wonder sceptics were not welcome in the past.

The defence of the IPCC to these errors has been to say that in a series of reports totalling 1,000s of pages a few errors are not unsurprising, true, and that they do not call into question the underlying science of climate change, also true. That misses the main point. At the highest level the IPCC was using unsubstantiated claims regarding the impact of climate change to further its case and scientists who were aware of the fallacies in these claims felt cowed and failed to speak out.
The IPCC is part of the United Nations system which has the delicate task of according equal status to all its members whilst also acting as a conduit for development aid to some of them. In Africa, Asia and South America (regions where these problems occurred) there are UN member countries in receipt of development assistance. Some of these do not have adequate budgets for their national meteorological services let alone the super computers, free access to the scientific literature and funds for conference attendance that ‘western’ climate scientists expect. One telling comment from one of the IPCC draft report reviewers was that he could not assess a comment as he was not able to access a copy of the Nature article which someone had mentioned in that comment.

So what for the future?

There have been suggestions that the IPCC has outlived its usefulness and should be replaced. This won’t happen. As Copenhagen showed, future action will depend on interaction between high carbon and low carbon emitting countries and this is only possible within the context of the UN. There have also been calls for the replacement of Dr Pachauri as Chairman of the IPCC. If this happens it will done following UN established procedures. Dr Pachauri was appointed to replace the previous chairman who was seen by the US to be too ‘warmist’; it was political move and political considerations will predominate in any replacement. The only debate will be whether he should be replaced by someone from another Asian country or whether it is now the turn of South America or Africa.

It is significant that the most articulate scepticism has come from a class which could be described as ‘technical non-academic professionals’. This describes people like Steve McIntyre (minerals exploitation), Anthony Watts (meteorologist) and David Holland (engineer). The leading sceptical blogs often have article-length postings from people, probably from a similar background, who have examined climate records in detail and raised serious questions about the way they have been processed. The scrutiny these people provide is more intensive and searching than that provided by peer review (aptly renamed ‘pal review’ by one blogger).

This suggests a way forward. There is a large group of technically qualified people who, whilst not climate scientists in the strict sense of the term, have spent their lives working with climate data: in areas such as water resources, urban drainage, irrigation, dam spillway design, etc. It is such people who have identified the weakness of the academic approach; they should be given a chance to see if they can do better.

Monday 8 February 2010

Nicholas Stern - "'A Blueprint for a Safer Planet"

This book could have equally have been called “A Blueprint for Copenhagen 2010”. Now, it might seem a bit unfair to comment on a book written before December 2010 in relation to what happened in that month. In Nicholas Stern’s case it is fully justified. As a former Chief Economist of the European Bank for Reconstruction and Development and of the World Bank and as the author of the UK government’s, globally influential, review of the Economics of Climate Change the author has been deeply involved in shaping policy.

The book is well written and the author has the ability to clarify complex issues. One of these is the relative merits and disadvantages of controlling CO2 emissions by a Carbon Tax or by Carbon Trading. With a Carbon Tax you know what it will cost but not how much it will reduce emissions; with Carbon Trading (Cap-and-Trade in the US) you know by how much it will reduce emissions but not what the financial implications are.

He also deals with one of the main criticisms of the Stern Review. Some economists argued that his conclusions were, in part, an outcome of his choice of discount rate. This is an important issue and it is worth looking briefly at what the “discount rate” is. The discount rate is used by economists for comparing alternative investments. For example when building a bridge how do you decide whether to build a 4-lane or a 6-lane bridge? If you build the 6-lane bridge part of the capacity will be unused for many years; if you build the 4-lane bridge you will have to face the cost and complication of widening it at some date in the future. The answer is to work out how much money you would have to invest now to pay for the bridge to be widened in the future. The rate of interest used for this calculation is called the discount rate and is typically around 6%. If the amount you have to invest now more than than the cost difference between a 6-lane and a 4-lane bridge you build a 4-lane bridge; if it is the other way around you build a 6-lane bridge now.

In his review Nicholas Stern used a much lower discount rate than the 6% mentioned above. He justifies his choice on two grounds. The first is that conventional economics assumes that whatever is being considered will not alter the ground rules; the type of bridge you build will not alter the economic assumptions underlying the comparison. With climate change, which could have major impacts globally, the assumptions of conventional economic are no longer valid. The second justification is that the real rate of return on safe long-term investments, such as government bonds, is also much lower, around 1.5%.

The crux of his argument is that mitigation, reducing the emission of greenhouse gases, makes more economic sense than adaptation, waiting for it happen and adjusting our life styles as a consequence.

No one can question Stern’s economic credentials and, wisely, he simply accepts the science. In a paragraph on adaption he shows a lack of understanding of why people quote the fact that the Romans made wine in Northern England. He suggests this is used as an example of adaptation. It is not. It used to demonstrate that at the time when Roman civilisations was spreading over Europe and North Africa temperatures were higher than they are today.

I started by saying the title of this book could have included “Copenhagen”. There is actually a chapter in the book called “The structure of a global deal.” The key elements identified are: a 50% cut in world emissions by 2050, developing countries to start reductions from 2020, carbon trading to be introduced world-wide, funding to reduce deforestation, investment in current and new low carbon energy and financial help to reduce the impact of climate change in developing countries. None of this was agreed.

The impasse at Copenhagen could be considered as a failure of the world’s governments to accept the arguments of this book. Despite that it is well worth reading as whatever the outcome economics will play a large part in decision that have to be taken.

Publisher: The Bodley Head, 2009
ISBN 9781847920386

Sunday 10 January 2010

Book review: Bjorn Lomborg - Cool it: : The Skeptical Environmentalist’s Guide to Global Warming

“There is no plan B” was the mantra of the climate activists and politicians who gathered in Copenhagen in December 2009 to hammer out a new agreement to limit carbon emissions. They were wrong. There is a plan B and this book describes it.

Although often called a ‘sceptic’ the appellation does not really apply to Bjorn Lomborg. He doesn’t dispute that global warming is real and is caused by humans. What he does question is the assumption that reducing CO2 emissions is the best or only way of dealing with its effects.

The author set up the “Copenhagen Consensus” which brought together a group of eminent economists to examine ways in which, with a limited amount of money, it would be possible to do most good to most people. The top three were: control of HIV/AIDS, providing micronutrients to tackle malnutrition and trade liberalisation. The last of these three has the double benefit of providing agriculturalists in the developing world with higher incomes and lower food costs to people in the developed world. The three options relating to CO2 emissions came in last.

He also suggests that the benefits of reducing CO2, even if Kyoto had achieved its targets, would have been minimal and delayed the effects of global warming in 2100 by only a few years

His book starts with the iconic polar bears. He points out that in the few areas where bear populations are falling most of the reduction is due to hunting. Other topics he covers and his assertions include:

• Heat deaths. More people die of cold in winter than die of heat in summer. Global warming would reduce weather related deaths.

• Rising sea levels. The rate of rise predicted by the IPCC is not markedly higher than the rise observed during the past century and better sea defences are a cheaper solution. He accepts that the gates designed to protect London from flooding have indeed been closed more frequently in recent years but points out that this was to keep water in during low flow periods not to keep it out during floods.

• Water stress. In most of the world, the increase in rainfall will more than compensate for the extra evaporation caused by higher temperatures.

• Tropical storms. Whilst there had been an apparent increase in storms as monitored by satellites over the last 30 years, longer term data shows no upward trend. The storm which flooded New Orleans did so because of inadequate flood defences not because it was an extraordinary storm.

• Malaria. This is not a disease limited to hot countries, one of the worst epidemics was in Russia in the 1920s, and increased temperature will not necessarily lead to an increase.

In each of these cases, and others that he examines, he compares the costs of a targeted response to the cost of controlling CO2 emissions. However what he compares is the low cost of each specific solution to the total cost of reducing CO2. This is false. The cost of reducing CO2 will be shared between all the problems that will be alleviated by CO2 reduction. Whether adopting this approach would have changed his conclusions is a moot point but he should have examined it.

Despite this reservation I recommend this book.

Ron

Publisher: : Marshall Cavendish (2007)

ISBN 978-0-462-09912-5

Saturday 9 January 2010

Book Review: Christopher Booker - The Global Warming Disaster

Christopher Booker is a columnist for the Telegraph (right of centre, highbrow). If there is a thread to his columns it is railing against abuses of authority and the resulting impact on individuals or (mostly small) businesses. If the authority stems from the EU then his invective steps up a gear. He is also the co-author of “Scared to Death” which looks at exaggerated scares, mainly but not always in the medical field (SARS, CJD/BSE, listeria, the Millennium bug, etc). A chapter of this book was entitled “Saving the Planet: Global Warming – the New Secular Religion.”

As he describes it himself he got interested in global warming via Nimbyism (NIMBY = Not in my Back Yard). He got involved in protests against a wind turbine near his home and from that started looking at the need for renewable energy sources and threat of global warming.

The book moves chronologically from cooling worries of the 1960s, past Hansen’s appearance before a sweltering Senate committee, via the successful legal challenge to Gore’s “Inconvenient Truth”, on to the recent cooling and the run-up to Copenhagen. One disadvantage of a chronological approach is that events which are logically consecutive get split up between chapters. So we get Mann and the Hockey-stick and the McIntyre and McKitrick challenge in chapter 4, Gore’s use of the Hockey-stick in his book and the Wegman report on it in chapter 6 and papers to support the Hockey-stick in chapter 7.

He also demonstrates a lack of altruism in some of the major players. Gore has invested heavily in alternative energy ventures and even offset his high carbon footprint by paying money to a company in which he has an interest. Maurice Strong, who was closely involved in setting up the UNEP and the IPCC, was implicated in the Iraq ‘money-for-food’ scandal and now has a major role in the multi-billion dollars carbon credits business. (Booker has recently returned to this theme in his newspaper pointing out the many business deals of Dr Rajendra Pachauri, head of the IPCC.)

It is commonplace to accuse “deniers” of being in cahoots with the energy industry. What this book shows is that money is also an important motivator among the ”warmists”.

In one sense the book is prophetic. It was written before the CRU emails and details the lack of independence of many of the leading climate scientists behind the IPCC reports. It was also written before COP15 in Copenhagen and identifies the problems of getting China and other developing countries on board for any binding international agreement.

If, like the author, you believe that the real “global warming disaster” is the vast amount of money being diverted to fight a chimera then this book will give you more ammunition. On the other hand, if believe that the effects of global warming are real and dangerous this book will do little to convince you otherwise.

Ron

Publisher: Continuum
ISBN: 9781441110527

Book Review: Ian Plimer, "Heaven and Earth – global warming: the missing science"

I wish I could recommend this book, I really do. After all a book which gives an overview of climate change from the creation of the Earth up to the present, which cites 2311 (mainly peer reviewed) references and runs to over 500 pages can’t be all bad. Can it?

Ian Plimer is both a distinguished geology professor and practicing geologist. As such he takes a long-term view of climate (billions of years not just decades or centuries). During this period earth has undergone changes to climate which make the changes recorded during historical time seem puny by comparison. His background also leads him to consider, and give more weight to, ‘geological’ forcing of climate change such as submarine vents.

The ‘meat’ of the book comes in five chapters headed “The Sun”, “Earth”, “Ice”, “Water” and “Air”. In the “Sun” chapter he argues that the sun as the sole source of external energy is the main driver of climate on earth and that the the interaction of the solar wind with cosmic rays is an important mechanism for climate change. The “earth” chapter covers volcanoes and Milankovitch cycles. He argues that that glaciers and sea ice have always advanced and retreated and that current changes are not unusual. He also discusses the physics of water and the influence some its properties (like the fact that ice floats on water) have on climate. In the “Air” chapter he examines the accuracy of temperature and CO2 measurement. Throughout the book he adopts an undeniably sceptical point view with regard to climate change. That said, he also appears to agree with some of the ‘consensus’ view. For example after saying that water vapour is the main greenhouse gas he continues “When times are warmer, water vapour evaporates more readily.” Later he also writes “Water vapour is an amplifier not a trigger.” He also concedes that “some of the increase in atmospheric CO2 measured over the last 150 years is of human origin.”

I learnt much from this book and many of the questions he raises are valid. For example he quotes from a number of studies which suggest that the residence time of CO2 in the atmosphere is around 5 years, much less that 50 to 200 years assumed by the IPCC.

So why don’t I feel able to recommend it? Well the answer, indirectly, comes from the author himself. In his introduction he says “Hypotheses are invalidated by just one item of contrary evidence, no matter how much confirming evidence is present.” The same could be set of a technical book. If it has errors then the reader cannot rely on it. That, unfortunately is the case with this book.
He says, for example, with reference to devastation of Hurricane Katrina, “The whole of the Texas Gulf area is subsiding. In the three years before the flood ... the city and the surrounding area had undergone rapid subsistence of about one metre.“ He gives no reference for this but later in the book cites a Nature paper (Dixon et al, 2006) which quotes a maximum rate of 28.6 mm/year but that is only at a few isolated spots in New Orleans and its surrounds. In other places nearby the subsidence is much less. He also claims that volcanoes produce more CO2 than fossil fuel burning whereas it is generally accepted than the ratio is 30 to 1 in opposite direction.

The author will often scrupulously cite references for relatively minor statements and then make sweeping statements without any source. In a rather confusing section, where mixes percent and absolute values, he says that 186 billion tons of CO2 enters the atmosphere of which 3.3% [equivalent to 6 billion tons, the accepted figure is 5 times higher] comes from human sources and ... 71 billion tons is exhaled by animals (including humans). This could do with a reference. Later in the same paragraph he says that Global warming did not cause the mass extinction in 65 Ma, and does give a reference.
In a similar way the author has a lot of graphs none of which are referenced and a least one of which is wrongly labelled. In the introduction he admits that they were “fly scratchings” which someone else converted into line diagrams for him so that lack of references is not surprising.

The book could also do with a good editor. Statements like “The winter of 1815-1816 was known as ‘the year without a summer’” should not have been allowed to stand. There are also numerous unnecessary repetitions. For example in one place he writes “...rebound is occurring in Scandinavia, Scotland and Canada after ice sheets up to 5 km thick melted over the last 14,000 years”. Two pages later we read “...ice sheets started to melt 14,700 years ago, and Scandinavia, Scotland and North America are currently rising...”.

The book was warmly welcomed by sceptics and attacked by warmists. There is indeed a lot of ammunition for sceptics but the errors and other shortcomings make the book easy prey for those who want to criticise it. If a second edition is published with the defects corrected it will be a useful contribution to the debate on global warming. Unless, and until, this is done I cannot recommend it.

Ron

Publisher: Quartet
ISBN: 9780704371668

Book Review: Fred Pearce, "The Last Generation: how nature will take her revenge for climate change"

Right from the start I had mixed feelings about this book. Fred Pearce is a science writer who I respect. Recently he published an article pointing out that there are reasons other than the risk of climate change for cutting back on the use of fossil fuels, citing their use for the production of artificial fertilisers. This corresponds to my own view which is that fossil fuels are a finite resource, at some point in the future they will inevitably be exhausted and the sooner we start to plan our transition the smoother it is likely to be. Also a few years ago he published a longish article in New Scientist based on some of my work which has prejudiced me in his favour.

On the other hand I believe that books with cover (front and back) pictures of a city engulfed in flames and alarmist titles like “The Last Generation” are counterproductive. Particularly when the only review quoted on the front cover reads “This is the most frightening book that I have ever read.” (Eat your heart out Stephen King.) So how did I resolve my conflicts?

The book is, literally, wide ranging. Polar research stations, Brazilian rain forests, the Sahara, Indonesian peat bogs, Siberian permafrost and glaciers in the four corners of the earth: all are part of the climatic picture he presents. In many cases the author has been to the parts of the world he is talking about: when he has not he has still managed to talk face-to-face with most of the scientists involved.

The science is accurately covered but not always without bias. He is too kind to Michael Mann and his Hockey-stick. The book was of course written before the release of the CRU emails but the Wegman report, which he does not mention, should have alerted him to the fact that other papers from a small group of authors which also produce ‘hockey-sticks’ could not be considered as independent confirmation.

Anybody who has studied climate change can be forgiving for thinking of it as a gradual process. The sedate dance of the earth and sun which follows the Milankovitch cycles of 20,000, 40,000 and 100,000 years. The 1,500 cycle which is so gentle that some people doubt its existence. The 11 year sunspot cycle which occasionally produced a diminuendo but always follows it by a gentle crescendo. What this book does is to show that this is not the case; that large changes in temperature, falls and rises, can come about in periods measured in decades rather than centuries or millennia.

Some of these changes are well attested, the Dansgaard-Oeschger events for example. Temperature estimates from Greenland ice cores these show that temperature can rise 2 to 10 C in a decade, remain there for a century or so and then fall. Others are more speculative. It is known that the warming from the last ice age was interrupted and the earth’s temperature dropped again for more than 1,000 years. The widely accepted reason for this is that vast quantities of dammed up melt water flowed suddenly into the north Atlantic and interrupted the circulation of the oceans. Some scientists speculate that melting caused by global warming could have a similar effect.

Whilst it alright for Stephen King to generate tension among his readers by hinting at vaguely defined dangers it does not go well with a scientific explanation of climate change. The author recognises this and is open about the fact that even when the speed and magnitude of the changes to climate are well supported by scientific evidence there is little agreement on what caused them. He says “After many generations of experiencing global climate stability, human society seems in imminent danger of returning to a world of crazy jumps. ...There is still a chance that the jumps won’t materialise... but the chances are against it.”

Whilst those who are already firmly convinced that global warming is a serious and imminent threat will find new arguments in this book many dyed-in-the-wool sceptics will remain unconvinced. I work with a wide variety of scientists from many different disciplines and nothing annoys them more than phrases such as “the science is settled”; they know from their own experience that science rarely achieves that degree of absolute certainty. A book like this which describes the science accurately and is honest about the uncertainties is more likely to convince open minded sceptics than one which only presents one apocalyptic side of the story.

So, Fred Pearce has retained my respect. But what about the title. Well, in the chapter on “Conclusions” he back-tracks a bit. He explains that he did not mean the title to imply that we would be last generation ever to live, only that we would be the last generation to live with certainty of a stable climate. I suspect that the publisher believed, rightly unfortunately, that an accurate title such as “Climate instability: a balanced review of the possibilities and uncertainties” would not sell.

Ron

Eden Project Books
ISBN: 9781903919880

Book Review: Mike Hulme, "Why we disagree about climate change: Understanding Controversy, Inaction and Opportunity".

Whether you believe that tackling climate change is the biggest threat to our planet, or whether you think it is all a con to squeeze more taxes out of a gullible public, the reasons you put forward for holding your views are not the real ones. You hold to your views because it suits you. That, in a nutshell, is the thesis of Mike Hulme. He would probably (in fact, more than probably) be horrified that I have summarised it in this way so let me expand on it.

The opinions we hold on a particular issue are determined by a matrix of complementary perceptions. How do we view science? What do we value? What beliefs do we hold? What do we fear? How do we want to be governed? The stand we take on climate change is shaped by our response to these different questions and helps to explain, for example, why global warming is generally viewed differently by the political left and the political right. The factors, which lead us to reach a decision on a political issue, are same ones as lead us to decide on all the other issues we have to face. This, as I am sure Mike Hulme would acknowledge, applies to author himself. As well as being a Professor at the School of Environmental Sciences of the University of East Anglia he is a committed Christian and many of his analogies have a biblical origin.

Hulme takes us through the questions I have listed above, and many others. For example in the section on risk he introduce two pairs of risk types. One of these pairs is situated/un-situated risk. Situated risk is when someone wants to build a waste incineration plant at the bottom of your garden; un-situated risk is the danger that the output from incineration plants all over the world will be dangerous. He second pair is affective/analytic. Affective risk is one you can actually experience, fumes from the incineration plant; analytic risk is one you only know about indirectly, published figures on the output of noxious gases from incinerations plants.

Climate change naturally falls into the category of ‘un-situated’ and ‘analytic’ risks. A lot of the effort of climate change campaigners has been to move the argument to ‘situated’ and ‘affected’ risks. Polar bears stranded on an ice floe far from safety are a ‘situated’ risk. Similarly, claiming that a large number of extreme weather events are caused by climate change increases the number of people for whom climate change becomes and ‘affective’ risk.
Given that Mike Hulme is a professor at the University of East Anglia, one of the world’s main centres for climate change research, the book is fairly balanced; in this he is being consistent with past statements where he has expressed worries that extreme language is having a negative effect on reactions to climate change. He also tackles one of the great taboo subjects in relation to climate change: population. After all total carbon dioxide emission can be considered as per capita consumption times population so why should all the effort be on the one (per capita consumption) not the other. China claims to have reduced its population growth by 300 million people as a result of its ‘one child’ policy. This, even at China’s relatively low per capita use, is equivalent to more that 5% of all carbon emissions and much more effective that Kyoto.

Despite this there are still few areas where his bias shows. In discussing participatory democracy he mentions the realclimate.org blog but not the more popular (although sceptical) wattusupwiththat.org. He quotes Eric Hobsbawm, the ‘British historian’, as saying, “Democracy, however desirable, is not an effective device for solving global or transnational problems.” What he fails to mention is that Hobsbawm is a life-long communist and once described Stalinist communism as a ‘worthwhile experiment’.

The last chapter, Beyond Climate Change, is in some ways the most intriguing. He introduces four ‘myths’ about climate change; the word myth is used in the anthropological sense of a deeply significant narrative about assumed truths. These are:
• Lamenting Eden – a search for an irenic state which existed before the fall,
• Presaging apocalypse - which sits well with eschatological calls to ‘repent as the end of the world is nigh’,
• Constructing Babel – referring to the attempt to build a city with a ‘tower that reaches to the heavens’ and signifying a desire to supplant God by human mastery of the universe,
• Celebrating Jubilee – based on the Jewish idea that every 50 years, soil, slaves and debtors should be liberated and humanity could make a fresh start.
Behind all these narratives is the pessimistic concept of a ‘wicked problem’; one which defies ‘rational and optimal’ solutions. As Hulme points out the world is now very much aware of the concept and threat of climate change but in reality little has been done. He suggests that climate change may be such a ‘wicked problem’.

Bjorn Lomborg is quoted three times in the book, always accurately and never in a disparaging way. As far as I can tell Lomborg is the only sceptic referenced in the book (though in one sense Lomborg is not a sceptic – he does not dispute climate change but only the much touted responses to it.) Could it be that Mike Hulme, a High Priest of climate change with privileged access to its inner sanctum, hold views not very dissimilar from those of “The Sceptical Environmentalist”? I doubt it but, as I said, the last chapter is intriguing.

I recommend this book.

Ron

Publisher: Cambridge University Press
ISBN: 9780521898690

Peer Review

Peer review is the process publishers of scientific journals use to ensure that the papers they publish are of an acceptable standard. Basically when they receive a paper for publication they send it off to a small group of people who have already published papers in the same field, the ‘peers’ of the author, for an opinion. If it is favourable they publish it; if not they reject it.

Much of the discussion around the leaked emails from the Climatic Research Unit at the University of East Anglia focussed on the peer review process. It appeared that some climate change scientists tried hard to stop sceptical papers being published or, if they had been published, from appearing in IPCC reports. At the same time these very climate scientists were citing an absence of critical peer reviewed papers as evidence that the scientific consensus accepted the concept of global warming.

One of the factors behind this was clearly shown in the Wegman report into the validity of the temperature “Hockey-stick” which showed that many papers on paleoclimatology were published by a relatively small group who co-authored papers with each other.

It is clearly not in the interest of Science (with a capital S) that valid criticisms should be suppressed; but also it is not in the interest of the reputation of a journal that it publishes below standard papers. Journals should have a clearly stated policy on the standards they expect for publication: awareness and understanding of the work of other experts, a clear statement of the advances or differences relative to other published work, a description of the data and analytical methods used. Provided that a paper meets these criteria it should get published.

Whilst it is relevant for a journal to identify the areas of research in which it is seeking papers it is invidious for it to identify what ‘line’ it takes. For example the British Royal Society on its web site has a statement showing that it clearly accepts that climate change is caused by people. This is wrong. It is of course perfectly reasonable for distinguished Fellows of the Royal Society to hold views on climate change, to express these views and even to write The Times with the letters FRS after their names. But, no matter how many of the Fellows hold a particular view it should never become the view of the society itself.

Often the reason that critics use the blogosphere is their comments relate to (sometimes blatant) flaws in the original paper. Journals are understandably reluctant to publish such criticism as it reveals flaws in their review process. (For a humorous take on this see: http://www.scribd.com/doc/18773744/How-to-Publish-a-Scientific-Comment-in-1-2-3-Easy-Steps)

An egregious example was the use of inverted sediment data. A paper (Mann et al, Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia, PNAS, 2008) was recently published on the assumption that extra lake sediment was indicative of increased temperature (whereas the converse is true). What is more in this case the amount of sediment had been artificially increased in recent years by nearby road building and agricultural work so any conclusions would have been false. To expect a sceptic to produce a paper for peer review reworking the misleading data is obviously not justified.

A related, but also important aspect of testing the validity of published papers concerns the release of data. In the past a scientist would do an experiment and report the results in a journal. Other scientists would try to replicate the result. If they got the same result, the findings of the initial experiment would be confirmed; if not, they would be rejected. In the case of climate science ‘the experiment’ consists of collecting, processing and analysing data. The hard work is in the collection and processing of the data; the interesting work is in the analysis. This, might for example, mean travelling around remote parts of Siberia drilling holes in tree rings, carefully preserving the samples and analysing them later in a laboratory to quantify growth rates as a proxy for temperature. It is therefore understandable that after doing all the hard work scientists would be reluctant to give their data away to all and sundry who could enjoy analysing them. It’s a bit like asking a ‘traditional’ scientist if you can come round and work in the laboratory that was used for the initial experiment.

On the other hand in most cases the cost of collecting the data came from the public purse so whilst the original worker might feel they have intellectual ownership of the data in reality it should be in the public domain.
We believe that data should be made available at the time of publication but accept that it is reasonable to make a small charge (similar to that made for copies of article to non-subscribers of a journal), to require a clear statement of why the data are needed and an acknowledgement of the source in any subsequent publication.

Opinions?

We have been planning to add an opinion page to our site for some time but little did we think we would have anything as exciting as the CRU emails and files to discuss. (If you have found this page you probably know what we’re talking about. In case you don’t, CRU stands for the Climatic Research Unit at the University of East Anglia in the UK. It produces one of world’s main climate data sets (in conjunction with the British Met Office) and several prominent climate researchers work there. In late November 2009 more than 1000 emails to and from researchers at the centre were released on the Internet together with several files of data, programs and notes. It is not clear whether it was work of a hacker or a whistle-blower (whichever it was the emails and files were carefully chosen).

Initial reaction was highly polarised. Many sceptical bloggers reacted with glee; this was the smoking gun, which proved that climate change was a hoax/conspiracy. On the other hand realclimate.org, which represents the views of many climate modellers, took the line that the emails revealed nothing other than robust scientific discussion.

After a slight lull the news of the emails became a big story in the mainstream media, in part because they were released a few weeks before the Copenhagen conference to agree a successor to the Kyoto protocol. This was followed by responses from the CRU and IPCC. The professor who figured in many of the emails stood down while an enquiry instituted by the university was carried out. The IPCC also announced an enquiry. Many of the emails dealt with the temperature record produced by the CRU and the university announced that the data set would be reworked over the next three years and as much as possible of the data put into the public domain. As this decision is the most significant change to come about as the result of the emails it is the one we concentrate on here. There are 5 main temperature data sets. Three of them, the one from CRU and two from the USA, use observed temperature readings, and start in the mid-19th century. The other two use data from satellite data and start in 1979. All five are in broad agreement for their common period.

The use of observed data has two main problems. Firstly the records are not continuous; stations close or are moved and new stations open. A symptom of this is that the number of stations available for analysis varies over time reaching a peak between 1970 to 1990 and then declined. Secondly urban development in the vicinity of a met station can make its reading unrepresentative of the surrounding area. Other changes are subtler. From about 1870 onwards thermometers were housed in a standard Stephenson screen, which had whitewashed wooded slats. The whitewash came to be replaced by different paints, which changes the reflectivity of the station. More recent automatic instruments have different housings. Another change is that temperature measurements at sea went over from using water temperature based on a bucket dipped into the sea to using the temperature of the cooling water intake.
We have two concerns about the new data set to be created.

The first is the concept of a single temperature series. In combining data from many sources a number of assumptions, about how to treat missing data for example, have to be made. Often it is not possible to demonstrate that one set of assumptions is better than another. In the right-hand sidebar we show three temperature series we have calculated ourselves using 5ยบ gridded data from the HadCRUt3v series (Figure below).





The first (red) data set using all the data is the same as the published HadCRU series. Temperature depends very heavily on latitude so for the second series we assumed that any grid filled represented temperature at the latitude (green line); this gives equal weight to each latitude band regardless of how many grids had data. The third alternative we examined was to use only grids, which had data for 90% or more of the time (blue). As can be seen there is not much difference between the first two series but third has some important differences. In particular the peak around 1940 is more pronounced as is the more recent temperature increase. We believe that several new series should be published with the assumptions behind each of clearly stated.

Secondly there is a worry that those developing the new series of measured data will ‘know what the answer should be’. For example the emails revealed there was some concern about the temperature peak in the mid 1940s; although not stated in the emails this was because climate models did not represent that peak. There might be a temptation to choose the data and the stations to fit the models.

For the new data to represent a real advance on previous data sets there is also need for some experimental work. One ‘experiment’ could be to set up a series of met stations with different types of Stephenson screens and different types of modern automatic sensors to see what differences, if any, there are. Another could be to set up a series of stations in urban and rural areas (or select carefully chosen stations currently in use) to develop a way of quantifying the urban heat island effect. Nighttime satellite images have already been used to identify urbanised areas; this could be taken a stage further to develop relationships between degree of urbanisation and temperature anomaly. A third experiment could be to measure sea temperature in different ways. Complicating all these experiments is a need to give good global coverage and to apply current findings to past climate records.

Welcome

Please use this blog to discuss anything in relation to the climate change data shown on our site. We very much look forward to your input.