All posts tagged Climate Change Analysis

Lamar Smith and Implementing effective policy on climate change

There has been considerable ire directed at Texan Congressman Lamar Smith for his Washington Post Op-Ed entitled “Overheated rhetoric on climate change doesn’t make for good policies“

Lamar begins

Climate change is an issue that needs to be discussed thoughtfully and objectively. Unfortunately, claims that distort the facts hinder the legitimate evaluation of policy options

Lamar concludes

Instead of pursuing heavy-handed regulations that imperil U.S. jobs and send jobs (and their emissions) overseas, we should take a step back from the unfounded claims of impending catastrophe and think critically about the challenge before us. Designing an appropriate public policy response to this challenge will require that we fully assess the facts and the uncertainties surrounding this issue, and that we set aside the hyped rhetoric.

I could not agree more. Judith Curry shows that the so-called “scientific” criticism is less balanced than the politician’s initial comments.

To think critically and objectively about any complex problem, it needs to be broken down into sub-sections with relevant areas of expertise. This is no more important in climate change policy, which science demands belief and people get lost in irrelevant detail. A starting point is to divide the issue into three parts, with the relevant experts in brackets.

1. Whether there is a potential problem. (Scientists)

2. Whether that potential problem is non-trivial. (Economists interpreting the scientists work)

3. Whether there is the ability to do something positive about that problem. (Economists and public policy-makers to formulate any policy. Economist/auditors, with some input from scientists, to interpret the results.)

1. Whether there is a potential problem.

The potential problem most would accept. Increase the level of greenhouse gases and average temperatures goes increase. It actually folds into the second.

2. Whether that potential problem is non-trivial.

But the second is far more important. The starting point to see if the size of the problem, it to break any potential impacts down into the components of magnitude, likelihood, time for changes to occur and the weighting that can be given to the scientific evidence. This is discussed here. Like in many other areas, the weighting we give to expert opinion should be based on a track record. Climate science is still very much in its infancy and many of the projected signposts were either wrong (worsening storms, accelerating sea level rises) or much too extreme (temperature rises). In fact any alleged successes are either through luck or through the initial prediction being so vague that it could hardly fail to be correct. There should also be a recognition concerning any potential benefits. For instance, Scotland would benefit from being a tad warmer, and increased CO2 may help plant growth. There is also a question of the quality of the climate model projections. There seems little or attempt at quality improvement through learning from past mistakes and building on successes. Further I see plenty of claims of being on the side of peer-reviewed science, and on consensus, whilst have a huge public-relations effort but little about building on the traditions of the greatest scientists, or learning from the philosophers of science. “Climate Science” seems somewhat out of that mainstream.

3. Whether there is the ability to do something positive about that problem.

The third is where the policy-makers step in. Are they able to deliver a policy that will tackle the issues at a lower costs than the benefits? To give a medical analogy, have they sufficient qualifications and the moral duty of care, that where they inflict painful treatments, the patient (the human race and/or Mother Gaia) is better off than if they had done nothing. Given the massive policy failures so far, the answer seems highly negative. Given that much of the effort is going into shutting down and policy discussion by believers in the science and in the policy, failures seem set to continue through deliberate negligence of this issue.

To take the medical analogy further, treatment is tempered by the uniqueness of the ailment and the track record in treating that ailment. For instance hip replacements have been performed for many years and are quite frequent, so the risks and pain of treatment, along with the mortality rates are known. So an otherwise reasonably healthy person of forty whose hip joints need replacing to enable them to walk would be recommended for the operation. A frail ninety year old would not. But we have never had human-caused climate change before. Indeed, there is a huge dispute about how serious the symptoms will actually be. They have not come to fruition just yet. Furthermore the “treatment” has not been properly tested. Neither have those devising the treatment any sort of qualifications or track record in devising similar treatments. Why do I know this? Because there has never been a global initiative to use economic tools to drive through a solution to a problem whose outward characteristics (though not necessarily the causes) are a naturally-occurring phenomena, neither are involved people who have experience is getting consensus on global issues, such as nuclear non-proliferation.

Note on the Moral View

I have a strong moral view that politicians should act to make the world a better place, as the underlying desired outcome of public service. It can be on the world stage or in a local community. Climate policy means imposing costs now to avoid much higher costs later. It might be a simplistic and naïve view, but the opposite – that politicians work to make a net negative impact, or do not care what effect they have, or simply work to serve some small factional interest (and to hell with everybody else) – are views that are at least distasteful and at worst downright evil. Like a medical professional, they have a duty of care to make sure there is a reasonable expectation that net positive outcomes will happen, and to monitor that progress.

Kevin Marshall

Are Climate Change and Obesity Linked?

Judith Curry has a (somewhat tongue-in-cheek) look at the links between climate change and obesity.

One of the two references is to the care2 website.

Consider the three alleged “links” between climate change and obesity that Dr Curry summarised:-

Rising inactivity rates because of hot temperatures
Drought-induced high prices on healthy foods
Food insecurity promotes unhealthy food choices

Rising inactivity is commonly thought to be due to less manual work, the rise of the car and evermore staring at the TV or computer. If a rise of 0.8C in temperature were a major factor then in Britain you would see (for instance) the Scots being more active than those in the South of England, or people being more active in winter than summer. In both cases the opposite is true.

Drought-induced high prices would have to show that droughts were the main cause of high prices of health foods compared to junk foods. Maybe convenience and taste have something more to do with the preference for unhealthy diets. Also you would need to show that rising food prices are connected to decreasing crop yields. Biofuels may have more with the rising food prices.

Food insecurity diminishes as per capita income rises, whilst obesity increases. That is the poorest of the world have hunger as a problem, whilst the rich countries have obesity as a growing problem. Obesity may be a problem of the poor in the developed nations, but food as a whole is not a problem.

The above article is a very extreme example of

The underdetermination thesis – the idea that any body of evidence can be explained by any number of mutually incompatible theories

Kuhn Vs.Popper: The Struggle for the Soul of Science – Steve Fuller 2003 Page 46.

Kevin Marshall

AR5 First Order Draft Summary for Policymakers – a few notes on pages 1 to 8

Alec Rawls has taken the brave step of releasing the first order draft of the UNIPCC AR5 Report. Anthony Watts has republished at Wattsupwiththat.

Although Alec Rawls published in breach of signed undertakings, I comment and quote the report in the public interest. There is more than a single, unequivocal, interpretation of the data. To claim otherwise is dogma. This dogma is being used to justify policies that promote net harm to western economies, particularly the poorer and more vulnerable sections of society. In the name of this dogma, impartiality is being annulled and dissenters called nutters.

I have started with some initial observations on the first eight pages on the Summary for Policymakers – the only bit that people ever read. Like utterings from the Kremlin on the 1970s and 1980s, the coded language says as much or more than the actual words.

Major points

No admission of lack of recent rise in the surface temperature record.
But the lack of recent rise is accounted for by a step change in the warming in the Southern Oceans.
AR4 got it wrong on decreasing precipitation in the tropics (which underlay Africagate), and they got it wrong on increasing hurricanes.
Sea level rise is not accelerating. In fact the recent rise since 1993 is similar to the 1930-1950 period.
Global glacier melt is not accelerating. Himalayas do not even get a mention.
Medieval Warm Period gains more recognition than the AR4. However, recent studies will render AR5 out of date before it even published.

Page 3 Lines 21-25.
On temperatures there is a cover-up of the recent lack of warming. They cannot admit that global average temperatures have not changed for 15 years.

Page 3 Lines 38-40. Precipitation in the tropics likely increased over the last decade, reversing a previous trend from mid-70s to mid-90s. The AR4 prediction of some African countries experiencing up to a 50% reduction in crop yields by 2020 (Africagate) was based upon a belief increasing extreme drought.

Page 3 Lines 46-48

Changes in many extreme weather and climate events have been observed, but the level of confidence in these changes varies widely depending on type of extreme and regions considered. Overall the most robust global changes are seen in measures of temperature {FAQ 2.2, 2.6} (see Table SPM.1).

Translation – Saying that an extreme weather events are evidence of global warming has no scientific validity. Best measures are of global temperature, which we can’t admit have been failing to rise.

Page 4 Line 14. An admission that previous IPCC reports got it wrong on tropical cyclones getting more extreme.

Page 4. Lot of stuff on Trenberth’s missing heat being in the oceans. Oceans have been warming since 1971. The lack of warming of air temperatures since the mid-90s could be accounted for by this comment on lines 36-37

It is very likely that the Southern Ocean has warmed throughout the full ocean depth since the 1990s, at a rate of about 0.03°C per decade.

The lack temperature rise is explained by the heating up of the oceans. Global warming is now confined to the Southern Ocean. It is imperceptible, so on the Southern perimeter it is not sufficient to have stopped the increase in Antarctic sea ice from extending slightly.

Then this

Warming of the ocean accounts for more than 90% of the extra energy stored by the Earth between 1971 and 2010. Upper ocean (0–700 m) heat content very likely increased at a rate between 74 [43 to 105] × 1012 W and 137 [120 to 154] × 1012 W for the relatively well-sampled 40 year period from 1971 to 2010. Warming has also been observed globally below 4000 m and below 1000 m in the Southern Ocean, in spite of sparse sampling (see Figure SPM.1). {3.2, Box 3.1, Figure 3.2, Figure 3.3}

The very likely heating of the Southern Ocean, is based on sparse sampling?

Page 4. Line 46. Seas have very likely become saltier. That is has become less alkaline. On Page 6 lines 30-31, Ph decline is 0.015 to 0.024 per decade over last 3 decades. Call becoming less alkaline “acidification”, which is inaccurate. Oceans are heading towards Ph neutrality.

Page 5. Glaciers are globally still shrinking. No mention of Himalayas, and no mention of global acceleration. Range is “210 [145 to 275] Gt yr^–1 to 371 [321 to 421] Gt yr^–1“. Omit to convert these to sea level rise. 210 Gt = 0.64mm. 421 Gt = 1.29mm (Oceans = 326.2m km² & 1 Gt water = 1 km³). In old money, glaciers are contributing 2.5 to 5.1 inches per century.

Page 5 Lines 47-49. Sea levels

It is virtually certain that over the 20th century the mean rate of increase was between 1.4 to 2.0 mm yr^-1, and between 2.7 and 3.7 mm yr^-1 since 1993. It is likely that rates of increase were similar to the latter between 1930 and 1950.

Translation. Sea levels are rising but not accelerating. If sea levels are a lagged response to rising surface temperatures, then (using the HADCRUT3 surface temperature data) we would expect the rise in sea levels to level off in the next few years, unless there is continued warming in the oceans.

Pages 6 to 7 Long-Term Perspective from Paleoclimatic Records

There was a medieval warm period, despite what Micheal Mann and others said in 1998 and 1999. But the MWP is less than the temperatures at the end of the twentieth century. However, due to time schedules for acceptance into AR5, they ignore Christiansen and Ljungqvist April 2012 and Ljungqvist et al 2012. The later, despite including discredited proxies such as Briffa’s notorious Yamal data, quite clearly shows rom 120 proxies that the 10^th century had higher temperatures than at the end of the 20^th century.

Similarly the Esper et. al 2012 of summer temperatures in Northern Scandinavia will render this part of the report out-of-date prior to it being published.

In 2006 the UNIPCC could bring themselves to bend the rules to allow in a corrupt scientific paper that suited their purposes, but this time they ignore two strong cases that undermine their case. If there is an AR6 around 2020, the UNIPCC will have to face the scientific evidence.

Page 8 The last IPCC report overestimated the impact of aerosols. The net impact of greenhouse gases and aerosols rises from 1.72 W m-² to 2.40 W m-². Negative forcings dramatically fall. The positive forcing impact falls, despite the major contributor, CO2 rising from 1.66 W m-²to 1.82 W m-². The net impact of CO2 reduces from 100% to around 75% of warming impact. It is no longer possible to talk of “rising CO2″ as a shorthand for anthropogenically-caused rising greenhouse gases.

NB – the SPM file I refer to can be accessed below. Please compare my comments with the file.

SummaryForPolicymakers_WG1AR5-SPM_FOD_Final

Kevin Marshall

3 Comments

by manicbeancounter on December 14, 2012 • Permalink

Posted in Climate Change Analysis, Global Warming, Science & Non-science

Tagged Alec Rawls, Anthony Watts, Climate Change Analysis, Himalayan Glaciers, Hockey Sticks, Kevin Trenberth, Sea Level Rise, UNIPCC AR5 draft

Posted by manicbeancounter on December 14, 2012

http://manicbeancounter.com/2012/12/14/ar5-first-order-draft-summary-for-policymakers-a-few-notes-on-pages-1-to-8/

Costs of Climate Change in Perspective

This is a draft proposal in which to frame our thinking about the climatic impacts of global warming, without getting lost in trivial details, or questioning motives. This builds upon my replication of the thesis of the Stern Review in a graphical form, although in a slightly modified format.

The continual rise in greenhouse gases due to human emissions is predicted to cause a substantial rise in average global temperatures. This in turn is predicted to lead severe disruption of the global climate. Scientists project that the costs (both to humankind and other life forms) will be nothing short of globally catastrophic.

That is

C_GW= f {K} (1)

The costs of global warming, C_GW are a function of the change in the global average surface temperatures K. This is not a linear function, but of increasing costs per unit of temperature rise. That is

C_GW= f {K^x} where x>1 (2)

Graphically

The curve is largely unknown, with large variations in the estimate of the slope. Furthermore, the function may be discontinuous as, there may be tipping points, beyond which the costly impacts of warming become magnified many times. Being unknown, the cost curve is an expectation derived from computer models. The equation thus becomes

E(C_GW)= f {K^x} (3)

The cost curve can be considered as having a number of elements the interrelated elements of magnitude M, time t and likelihood L. There are also costs involved in taking actions based on false expectations. Over a time period, costs are normally discounted, and when considering a policy response, a weighting W should be given to the scientific evidence. That is

E(C_GW)=f {M,1/t,L,│Pr-E()│,r,W} (4)

Magnitude M is the both severity and extent of the impacts on humankind or the planet in general.

Time t is highly relevant to the severity of the problem. Rapid changes in conditions are far more costly than gradual changes. Also impacts in the near future are more costly than those in the more distant future due to the shorter time horizon to put in place measures to lessen those costs.

Likelihood L is also relevant to the issue. Discounting a possible cost that is not certain to happen by the expected likelihood of that occurrence enables unlikely, but catastrophic, events to be considered alongside near certain events.

│Pr-E()│ is the difference between the predicted outcome, based on the best analysis of current data at the local level, and the expected outcome, that forms the basis of adaptive responses. It can work two ways. If there is a failure to predict and adapt to changing conditions then there is a cost. If there is adaptation to anticipation future condition that does not emerge, or is less severe than forecast, there is also a cost. │Pr-E()│= 0 when the outturn is exactly as forecast in every case. Given the uncertainty of future outcomes, there will always be costs incurred would be unnecessary with perfect knowledge.

Discount rate r is a device that recognizes that people prioritize according to time horizons. Discounting future costs or revenue enables us to evaluate the discount future alongside the near future.

Finally the Weighting (W) is concerned with the strength of the evidence. How much credence do you give to projections about the future? Here is where value judgements come into play. I believe that we should not completely ignore alarming projections about the future for which there is weak evidence, but neither should we accept such evidence as the only possible future scenario. Consider the following quotation.

There are uncertain truths — even true statements that we may take to be false — but there are no uncertain certainties. Since we can never know anything for sure, it is simply not worth searching for certainty; but it is well worth searching for truth; and we do this chiefly by searching for mistakes, so that we have to correct them.

Popper, Karl. In Search of a Better World. 1984.

Popper was concerned with hypothesis testing, whilst we are concerned here with accurate projections about states well into the future. However, the same principles apply. We should search for the truth, by looking for mistakes and (in the context of projections) inaccurate perceptions as well. However, this is not to be dismissive of uncertainties. If future climate catastrophe is the true future scenario, the evidence, or signal, will be weak amongst historical data where natural climate variability is quite large. This is illustrated in the graphic below.

The precarious nature of climate costs prediction.

Historical data is based upon an area where the signal of future catastrophe is weak.

Projecting on the basis of this signal is prone to large errors.

In light of this, it is necessary to concentrate on positive criticism, with giving due weighting to the evidence.

Looking at individual studies, due weighting might include the following:-

Uses verification procedures from other disciplines
Similarity of results from using different statistical methods and tests to analyse the data
Similarity of results using different data sets
Corroborated by other techniques to obtain similar results
Consistency of results over time as historical data sets become larger and more accurate
Consistency of results as data gathering becomes independent of the scientific theorists
Consistency of results as data analysis techniques become more open, and standards developed
Focus on projections on the local level (sub-regional) level, for which adaptive responses might be possible

To gain increased confidence in the projections, due weighting might include the following:-

Making way-marker predictions that are accurate
Lack of way-marker predictions that are contradicted
Acknowledgement of, and taking account of, way-marker predictions that are contradicted
Major pattern predictions that are generally accurate
Increasing precision and accuracy as techniques develop
Changing the perceptions of the magnitude and likelihood of future costs based on new data
Challenging and removal of conflicts of interest that arise from scientists verifying their own projections

Kevin Marshall

3 Comments

by manicbeancounter on October 26, 2012 • Permalink

Posted in Climate Change Economics, Global Warming

Tagged Climate Change Analysis, Climate change policy, Global Warming, The Stern Review

Posted by manicbeancounter on October 26, 2012

http://manicbeancounter.com/2012/10/26/costs-of-climate-change-in-perspective/

RWE Atlantic Array to gain GBP169m in Windfall Profits

I have worked in management accounts in manufacturing industry for over 25 years. In that time I have learnt that audit controls are imposed to stop the potential for fraud, by eliminating any scope for fraud. In Britain climate change arena, conflicts of interest are huge, but not considered important. This is an example of why truly independent oversight is required.

In July there was ministerial sign-off of a proposed to change the Renewables Obligation (RO) with respect to offshore wind power. Assuming that this proposal is enacted and the Atlantic Array gets the green light, I calculate will give a £169m (US$262m) windfall profit to the scheme in the first ten years of operation.

The numbers behind this are eye-watering.

The revenue from a wind farm is from selling the electricity produced to the grid. This is currently 4.7p per kwh. I will assume that this will remain constant for until 2025. This might be a heroic assumption given that under current policies Britain will be producing far less electricity than demanded, but it is beside the point of this posting. What is relevant is the subsidy from electricity bills. The RO currently gives renewables a subsidy of £41.38 per megawatt hour. This is the rate for onshore wind. However, to encourage offshore wind power, this currently attracts a factor of 2.0 times the standard rate. In 2009 this was planned to reduce to 1.5 times the standard rate from 2014*. The new proposals are to give a more gradual and delayed decrease to 1.9 in 2015/16 and 1.8 in 2016/17. I have assumed that this will continue until the 1.5 level is reached.

In Germany the average output from the wind farms is just 16.3%. However, Britain is somewhat more exposed, especially the Bristol Channel. It is reasonable to assume to that average output will be 25% of capacity. Then I have assumed that RWE will choose to build the maximum proposed capacity of 1390MW. The lower end is 1000MW.

Calculations over a 10 year period are

The difference will mean an extra £168,572,951 windfall for RWE.

There is however a potential flaw in my analysis. If the Renewables Obligation works like the solar panels for houses, then the rate is fixed at the time of application. In other words, a scheme coming on stream in 2015 would now attract 2.0 ROC, instead of 1.5 for every year for 10 years.

If my analysis is correct, the difference will mean an extra £684,633,697 windfall for RWE over a 10 year period. That is $1.07 bn dollars. This from (the largest) of a number of similar projects.

1 Comment

by manicbeancounter on August 28, 2012 • Permalink

Posted in Atlantic Array, Climate Change Analysis, Climate Change Economics

Tagged Atlantic Array, Climate Change Analysis, Conflicts of Interest, Lundy Island, Tim Yeo

Posted by manicbeancounter on August 28, 2012

http://manicbeancounter.com/2012/08/28/rwe-atlantic-array-to-gain-gbp169m-in-windfall-profits/

History Of How The Hockey Stick Was Manufactured

Reblogged from Real Science:

There wasn't any hockey stick prior to the year 2000.

The 1990 IPCC report showed that temperatures were much cooler than 800 years ago.

www.ipcc.ch/ipccreports/far/wg_I/ipcc_far_wg_I_full_report.pdf

Briffa's trees showed a sharp decline in temperatures after 1940

The 1975 National Academy Of Sciences report also showed a sharp decline in temperatures after 1940

www.sciencenews.org/view/download/id/37739/name/CHILLING_POSSIBILITIES

NCAR reported a sharp drop in temperatures after 1940…

Gergis 2012 Mark 2 – Hurdles to overcome

BishopHill reported yesterday on the withdrawn Gergis paper that

The authors are currently reviewing the data and methods. The revised paper will be re-submitted to the Journal of Climate by the end of July and it will be sent out for peer review again.

It is worth listing the long list of criticisms that have been made of the paper. There are a lot of hurdles to overcome before Gergis et al 2012 should qualify for the status of a scientific paper.

My own, quite basic, points are:-

Too few proxies for such a large area. Just 27 for > 5% of the globe.
Even then, 6 are well outside the area.
Of these six, Gergis’s table makes it appear 3 are inside the area. My analysis is below.
Despite huge area, there are significant clusters – with massive differences between proxies at the same or nearby sites.
There are no proxies from the sub-continental land mass of Australia.
Need to remove the Palmyra Proxy because (a) it has errant readings (b) fails the ‘t’ test (c) > 2000km outside of the area, in the Northern Hemisphere.
Without Palmyra the medieval period becomes the warmest of the millennium. But with just two tree ring proxies, one at 42^O South and the other at 43^O S representing an range from 0 to 50^O S, this is hardly reliable. See the sum of proxies by year. Palmyra is the coral proxy in the 12^th, 14^th and 15^th centuries.

On top of this are Steve McIntyre’s (with assistance from JeanS and RomanM) more fundamental criticisms:-

The filtering method of Gergis excluded the high quality Law Dome series, but included the lower quality Vostok data, and the Oroko tree ring proxy. McIntyre notes that Jones and Mann 2003 rejected Oroko, but included Law Dome on different criteria.
Gergis screening correlations were incorrectly calculated. JeanS calculated properly. Only 6 out of 27 proxies passed. (NB none of the six proxies outside the area passed)
The Gergis initially screened 62 proxies. Given that the screening included proxies that should not have included 21 proxies, but should it have included some of the 35 excluded proxies. We do not know, as Gergis has refused to reveal these excluded proxies.
Screening creates a bias in the results in favour of the desired result if that correlation is with a short period of the data. RomanM states the issues succinctly here. My, more colloquial take, is that if the proxies (to some extent) randomly show C20th warming or not, then you will accept proxies with a C20th uptick. If proxies show previous fluctuations (to some extent) randomly and (to some extent) independently of the C20th uptick, then those previous fluctuations will be understated. There only has to be a minor amount of randomness to show bias given that a major conclusion was

The average reconstructed temperature anomaly in Australasia during A.D. 1238-1267, the warmest 30-year pre-instrumental period, is 0.09°C (±0.19°C) below 1961-1990 levels.

UPDATE 03/08/12

The end of July submissions date seems to have slipped to the end of September.

7 Comments

by manicbeancounter on June 27, 2012 • Permalink

Posted in Australia, Climate Change, Climate Change Analysis, Hockey Sticks, Science & Non-science

Tagged Australasia, Bishop Hill, Climate Audit, Climate Change Analysis, Gergis 2012, Hockey Sticks, Steve McIntyre

Posted by manicbeancounter on June 27, 2012

http://manicbeancounter.com/2012/06/27/gergis-2012-mark-2-hurdles-to-overcome/

How Gergis Suppressed The Medieval Warm Period

The now withdrawn Gergis paper proudly proclaimed in the abstract

The average reconstructed temperature anomaly in Australasia during A.D. 1238-1267, the warmest 30-year pre-instrumental period, is 0.09°C (±0.19°C) below 1961-1990 levels.

On this basis, Gergis was able to say

A preliminary assessment of the roles of solar, volcanic, and anthropogenic forcings and natural ocean–atmosphere variability is performed using CSIRO Mk3L model simulations and independent palaeoclimate records. Solar and volcanic forcing does not have a marked influence on reconstructed Australasian temperature variations, which appear to be masked by internal variability.

This conclusion is from a single rogue proxy – the coral proxy from Palmyra Atoll.

There were only three temperature proxies covering this medieval peak period. Both Mt. Read in Tasmania and Oroko in New Zealand are tree ring proxies that cover the entire millennium. The Palymyra Atoll coral proxy data covers just 398 years over 4 periods. These are 1151-1221, 1319-1465, 1637-1704 and 1888-1999. Following Gergis, I have calculated the decadal averages. Below is the plot from my pivot table for the three proxies.

I contend that Palmyra is distinctly “odd” due to the following.

Nowhere in the world am I aware of a single instance of massive cooling during the early 13^th Century. If not rogue data, the it must be a purely local phenomena.
Nowhere in the world am I aware of a single instance of massive cooling during the 17^th Century. Nor was I aware the early 17^th century had significant warm period. If not rogue data, it must be a purely local phenomena.
The Hadcrut3 global temperature set has slight cooling at the end of the 19^th century / start of the 20^th Century, and a warming period from 1910 to 1940 almost as large as the warming period from 1975 to 1998. If not rogue data, it must be a purely local phenomena.
The post 1960 warming trend is phenomenal. In fact it makes the twentieth century warming trend the largest of all the 27 proxies. (See table “Analysis of the Proxies in Gergis et al. 2012” below)

For these three reasons it would appear to be an outlier. So what is the impact?

I looked at the decadal average of the two tree-ring proxies and ranked the hundred decades from 1 for the highest to 100 for the lowest. I then took the decadal average of the three tree-ring proxies and similarly ranked the results.

The change is the decadal ranking was as follows:-

The medieval warm period is suppressed, and the twentieth century is “enhanced”.

Now let us be clear. There were 24 other proxies in the data set. However, none of the others were prior to 1430. Therefore the impact on the overall ranking will not be quite so marked. However, the fact remains that the conclusion that last decade of the 20^th century is the warmest of the millennium is based on this one rogue data set.

But there are two more reasons that the Palmyra data set should not have been included in the reconstruction.

Firstly, the Gergis paper was withdrawn upon the publication of the JeanS ‘Gergis Significance’ t-values. Unsurprisingly, Palmyra was one of the proxies that failed the t-test, so is a rogue data set. See table below.

Secondly, is geography. The study is a “temperature reconstruction for the combined land and oceanic region of Australasia (0°S-50°S, 110°E-180°E)“. Palmyra Atoll is located at 5°52′ N, 162°06′ W, or over 2100Km (1300 miles) outside the study area.

Conclusion.

The Palmyra Atoll coral proxy study is clearly an outlier statistically and geographically. In no way can it be considered a suitable proxy for the Australasia region, yet the major, headline, conclusion of the Gergis et al 2012 temperature reconstruction relied upon it.

8 Comments

by manicbeancounter on June 11, 2012 • Permalink

Posted in Climate Change, Climate Change Analysis, Hockey Sticks

Tagged Climate Change Analysis, Gergis 2012, Hockey Sticks, Steve McIntyre

Posted by manicbeancounter on June 11, 2012

http://manicbeancounter.com/2012/06/11/how-gergis-suppressed-the-medieval-warm-period/

Mid-Pacific Coral temperature proxies from Gergis et al. 2012

How odd is the Palmyra Atoll Coral Proxy?

In the last post I noted that there was something odd about the Palmyra proxy used in the Gergis paper, particularly in the late 20^th century. This is at 5°52′ N, 162°06′ W.

There are four other coral proxies in the Mid-Pacific area. There are two proxy studies from
Rarotonga in the Cook Islands at 21° 14′ 0″ S, 159° 47′ 0″ W and two from the Fiji. For all five proxies I calculated a nine year centred moving average.

Palmyra shows a late 20^th century warming trend more than twice that of the other series. Unless there is a locally recorded temperature anomaly on the atoll, then this is clearly wrong. If there is a local temperature spike, then it one should question why it is included in a reconstruction for which it is over 2000km outside the boundary. Either way it should be deleted from the study.

So how reliable are coral proxies. Here we have two pairs. If they are a good proxy for temperature, then they should be a good proxy for each other. On Fiji, they studies be less than 150km apart and on Rarotonga less than 10km apart, meaning they should be near identical. So I have plotted the differences between the moving averages.

It is not a statistically sound method, but indicative of the real issues with the proxy data sets. It also seems that the further back, the greater the consistency. The Palmyra study has four sections, the oldest of which starts in the 12^th Century. Although Gergis claims to have done a series of tests for robustness, there is no correlation test over the known temperature record. Given that a central conclusion is:-

The average reconstructed temperature anomaly in Australasia during A.D. 1238-1267, the warmest 30-year pre-instrumental period, is 0.09°C (±0.19°C) below 1961-1990 levels.

Given that there is some question of the selection of the ice core studies at Vostok in preference for the closer and more robust studies at Ice Dome, then central conclusion of the study is not credible on such a small number of proxies.

2 Comments

by manicbeancounter on June 6, 2012 • Permalink

Posted in Climate Change, Hockey Sticks

Tagged Climate Change Analysis, Gergis 2012, Hockey Sticks, Palmyra Atoll, Temperature Reconstructions

Posted by manicbeancounter on June 6, 2012

http://manicbeancounter.com/2012/06/06/mid-pacific-coral-temperature-proxies-from-gergis-et-al-2012/

Forcings – Hansen et al 2000 v UNIPCC 2007

Two months ago I did an analysis of aerosols in the UNIPCC AR4 report, observing that

That the IPCC can’t add up.
The figures appear contrived to show that only CO2 was the problem.

Anthony Watts has a posting today “Shocker: The Hansen/GISS team paper that says: “we argue that rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases“. This is based on the James Hansen (and others) paper analysing natural forcings, with the following graphic.

Hansen et al Figure 1: Estimated climate forcings between 1850 and 2000.

I thought that I would do a quick the comparison between what the IPCC were saying in 2007, with what Hansen et al. were saying in 2000.

According to the UNIPCC

Hansen underestimated CO2 component.
Hansen overestimated the CH4 component.
Hansen overestimated the impact of the sun.

However, Hanson could counter that the UNIPCC have completely forgotten about the impact of volcanoes.

It could be completely coincidental, that further analysis by climate scientists gives a greater role to CO2, and therefore even stronger justification for constraining CO2 emissions. However, although they became more certain on positive forcings, they are less certain than Hansen on aerosols. It gives even greater credence to the cynical view that the climate science community are exaggerating the influence of anthropogenic forcings on climate. Given the billions of dollars annually being poured into research one could reasonably expect a reduction in the uncertainties over time.

2 Comments

by manicbeancounter on June 3, 2012 • Permalink

Posted in Climate Change Analysis

Tagged Aerosols, Climate Change Analysis, James Hansen, UNIPCC AR4, Wattsupwiththat

Posted by manicbeancounter on June 3, 2012

http://manicbeancounter.com/2012/06/03/forcings-hansen-et-al-2000-v-unipcc-2007/

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History Of How The Hockey Stick Was Manufactured

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Forcings – Hansen et al 2000 v UNIPCC 2007

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