All posts in category Science & Non-science

Climate Change – Evaluating the Evidence

Roger Pielke Jr. reports here that the Australian Prime Minister proposes to form a citizens’s assembly on climate change. She says

And so today I announce that if we are re-elected, I will develop a dedicated process – a Citizens’ Assembly – to examine over 12 months the evidence on climate change, the case for action and the possible consequences of introducing a market-based approach to limiting and reducing carbon emissions.

 

Pielke finds problems with the last part. My problem is with examining the evidence on climate change. Given that the climate science is highly polarised, with a lot of complex arguments, this is not something that your average citizen can pronounce upon. Also, given that on one side you have a consensus of experts pronouncing the science is settled, with it being widely promoted that the opposition are just spokespeople for the fossil fuel lobby, there will be a vast majority in support of action and a small minority of dogged skeptics.

The only way for a consensus to be formed objectively is for the panel to act as a jury, with

  1. Clear guidelines as to what constitutes evidence, and levels of evidence to sort out the facts and strongly-verified science, from the, weak circumstantial evidence, and hearsay.*
  2. For a clearly defined barrier to establish the need for action. Like in a criminal trial under English common law, where you have to establish beyond reasonable doubt. The barrier may be set lower (like in civil cases), but it still needs to be there.
  3. To clearly separate the science from the policy. That is to clearly take into account the costs, benefits and risks of policy changes.

 

*To be clearer, the levels of evidence in decreasing order are.

  1. Facts
  2. Established or independently verified (& not rebutted) science.
  3. Peer-reviewed statistically verified science.
  4. Other peer-reviewed science based on circumstantial evidence.
  5. Papers by advocacy groups.
  6. Hearsay. E.g. “The vast majority accept…..”
by Kevin VS Marshall (Manicbeancounter) on 24/07/2010  •  Permalink
Posted in Global Warming, Science & Non-science
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Posted by Kevin VS Marshall (Manicbeancounter) on 24/07/2010

https://manicbeancounter.com/2010/07/24/climate-change-evaluating-the-evidence/

Muir Russell & unpicking Global Warming

If you believe that the science is settled on Global Warming is settled, listen to Roger Harrabin’s comment at the end of this clip from Radio 4 this morning on 7th July. To Quote

“98% of scientists believe that humans are warming the planet, the question is by how much”

The is a distinct change from just 9 months ago, pre ClimateGate. Is it a case of “We are all Skeptics Now?”.

Following on on from Tim Worstall’s recommendation of the Stoat’s summary of the Global Warming case.

For an empirical science, maybe a distinction between science and non-science is to admit to the limits of the certainties, something that the IPCC consensus has been at pains to avoid.

by Kevin VS Marshall (Manicbeancounter) on 07/07/2010  •  Permalink
Posted in Climate Change, Global Warming, Science & Non-science
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Posted by Kevin VS Marshall (Manicbeancounter) on 07/07/2010

https://manicbeancounter.com/2010/07/07/muir-russell-unpicking-global-warming/

Global Warming – a simple summary unpicked

Tim Worstall points readers to a moderate view of global warming from the Stoat at scienceblogs.com.

Unlike most libertarians, Worstall accepts the basic science behind global warming, but disagrees with the policy implications.

William Connolly (Stoat) quotes a list of the main points he made in 2004.

The main points that most would agree on as “the consensus” are:

1. The earth is getting warmer (0.6 +/- 0.2 oC in the past century; 0.1 0.17 oC /decade over the last 30 years (see update)) [ch 2]
2. People are causing this [ch 12] (see update)
3. If GHG emissions continue, the warming will continue and indeed accelerate [ch 9]
4. (This will be a problem and we ought to do something about it)

These are in descending order of certainty. Further

 

In the years since I wrote that nothing has come along to overturn any of that, and much has come in to buttress it. 1, 2 and 3 are now strong enough to be considered “essentially true”; the arguments that claim any of them are false are now dull and uninteresting and without scientific validity. Pretty well all of the meaningful scientific skeptics have now given up trying to argue that.  

 

Let me get really dull and uninteresting, and try to access the scope of scientific validity.

  1. The earth got warmer in the last century. It got warmer in spurts, followed by periods of stability.
  2. People are highly likely to be contributing this to some extent. It could account (though unlikely) account for greater than 100% of the warming. Certainly, the planet is over 30oC warmer than it would have been without the natural greenhouse effect, consisting mostly of water vapour. However,

–                 The recent rise in the total level of anthropogenic greenhouse gases has probably added less than 2% to the total, for a 2% rise in temperature. A physicist would expect diminishing temperature rises for incremental rise in the greenhouse blanket, not increasing ones.

–                 Furthermore, then temperature rises have been in spurts – from 1914 to 1940 and from 1977 to 2000. In between global temperatures did not rise. If you look at global growth rates, there was low growth in the inter-war period (with the Great Depression in the middle), high growth from 1945 to 1973 (the year of the oil crisis) and lower growth to 1998, then the greatest level of growth in world history for the next decade. If there is any correlation, it is negative.

–                 The Hockey Stick episode. The great effort that has been put into eliminating the medieval warm period, to demonstrate that the twentieth century warming is unprecedented, should provide strong circumstantial evidence of the doubt that the data engenders. Compare the arguments of the climate sceptic Steve McIntyre (McIntyre S, 2008b is a readable introduction.) with a 2005 consensus view. This is basically a cross-check. If there have been large fluctuations in recent, pre-industrial history. In particular, higher temperatures a few hundred years ago, and an unusually cold period in the 17th to early 19th centuries, then it would be more likely that the most of the 20th century warming was natural.

3. If greenhouse gases keep increasing, then temperatures will, ceteris paribus, also increase. However, that they will accelerate because of positive feedbacks (water vapour – the principle greenhouse gas – is forecast to rise as a result of the temperature rise brought about by the rise in CO2) may contradict, the limited, observed data (Lindzen and Choi 2009 pdf).

 

The science is much more nuanced. There are large uncertainties in the data and still bigger ones in the forecasts. So a huge range of conclusions is valid. The appointed leaders cover this with dogmatic certainties and untenable forecasts, along with being quick to doubt the motives, competence or even sanity of anyone who stands in their way. Further they still do not see a problem when biased analysis and broken procedures are revealed. Nor manipulation of the data to get the desired results. Nor attempts to block adverse science from being published. Their very lack of humility and dogma is opening the door to those who say it is all a conspiracy or a scam.

by Kevin VS Marshall (Manicbeancounter) on 05/07/2010  •  Permalink
Posted in Climate Change, Global Warming, Science & Non-science

Posted by Kevin VS Marshall (Manicbeancounter) on 05/07/2010

https://manicbeancounter.com/2010/07/05/global-warming-a-simple-summary-unpicked/

Climate Tipping Points – The Real Conclusion beneath Scientists Opinion

The Independent reports on a new paper about the likelihood of a climatic tipping point being reached by 2200. How did they achieve this? Have they come up with a new wonder-model? Or by achieving a fundamental refinement of the existing models? No, the answer is more mundane. They interviewed 14 leading scientists on climate change, asking them some sophisticated (but leading) questions. It is an opinion poll, with a biased and insignificant sample. But it is revealing about the quality of climate change “science”.

  For instance consider the following from the abstract.

 

Quote 1

“The width and median values of the probability distributions elicited from the different experts for future global mean temperature change under the specified forcing trajectories vary considerably.”

 

   I thought statistical results could only come from statistical analysis, not experts reviewing the literature.

 

Quote 2

“For a forcing trajectory that stabilized at 7 Wm-2 in 2200, 13 of the 14 experts judged the probability that the climate system would undergo, or be irrevocably committed to, a “basic state change” as ≥0.5.”

 

   In science, a probability can only be calculated from the data, and can be subjected to a battery of tests for robustness. In common parlance probabilities are used as an expression of opinion. Like the IPCC forecasts for temperature the distinction is blurred. In this case it appears to be the latter, so should be clearly stated as such in a scientific journal.

   A second problem is the forcing trajectory being stabilised at 7 Wm-2. That is on top of the existing 324 Wm-2, a 2% rise (See IPCC AR4 page 96). The current greenhouse effect makes average global temperatures of 14oC up to 33oC higher than they would have otherwise been. If the effect were a linear one, then I would expect this impact to be 0.7oC. However I would expect the relationship to be a non-linear, with a diminishing marginal impact for each successive increase in the greenhouse forcings. To get to the median IPCC predicted increase of 3.5oC for this century would require huge increasing impact. Maybe climatologists are too lost in their consensus to see the bigger picture provided by data analysis.

 

Quote 3

“Finally, most experts anticipated that over the next 20 years research will be able to achieve only modest reductions in their degree of uncertainty.”

 

Do you want some accurate, scientific, analysis of the climatic instability that will be brought about by rising temperatures, in turn caused by rising CO2? The best experts cannot see this being achieved until long after they retired.

 

The Real Conclusion

The top climate scientists tacitly acknowledge that there is no robust, scientific basis for the climatic instability forecast.

Hat tip: Richard North at EU Referendum

by Kevin VS Marshall (Manicbeancounter) on 30/06/2010  •  Permalink
Posted in Climate Change, Science & Non-science
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Posted by Kevin VS Marshall (Manicbeancounter) on 30/06/2010

https://manicbeancounter.com/2010/06/30/climate-tipping-points-%e2%80%93-the-real-conclusion-beneath-scientists-opinion/

Climate Change – New Scientist puts smears before science

The latest issue of the New Scientist features a series of articles on climate change deniers (see below). The second – “Living in denial: When a sceptic isn’t a sceptic” compares “climate” deniers with deniers of the holocaust, 9/11, Aids, vaccine, evolution and the harmful effects of tobacco. It is this last that I have just posted a fuller analysis.

Alternatively consider these two arguments.

1. The proposition that smoking is harmful to health was initially based on a study of 34,000 British Doctors. The study itself was “heralded a new type of scientific research”. The results have been replicated, refined and further issues identified. To deny that smoking is harmful  to health is equivalent to denying a simple fact. By implication you are going against science, so must either have an ulterior motive or be a crank.

2. The proposition that the climate system will be changed catastrophically is agreed upon by a very large number of scientists, as a result of a huge numbers published papers, using similar empirical methods to that used in medical research. So those who oppose the AGW consensus, must be equivalent to those who oppose the medical consensus on smoking.

This is bad science seeking to piggy-back on the reputation of good science. If the results of climate change science were so clearly unambiguous, then the counter-arguments would be easily dismissed by clear presentation of that science. But there are deep flaws in the science, so smears are necessary.  

 

 Hatip wattsupwiththat From their article is the following:-

 
Here’s links to all the New Scientist articles on “denial”. They did include one article from Michael Fitzpatrick that is a 
feeble attempt at balance,but even it too strays into the ugly territory of comparing climate skeptics with AIDS deniers.
by Kevin VS Marshall (Manicbeancounter) on 15/05/2010  •  Permalink
Posted in Climate Change, Global Warming, Science & Non-science, Science - the Boundaries
Tagged ,

Posted by Kevin VS Marshall (Manicbeancounter) on 15/05/2010

https://manicbeancounter.com/2010/05/15/climate-change-new-scientist-puts-smears-before-science/

Himalayan Glaciers, the UNIPCC response and an Inquiry

The response of the UNIPCC to the revelation that its 2007 prediction that the Himalayan Glaciers would disappear by 2035 has been

  1. To claim the allegations are voodoo science.
  2. To apologize, but say it is a one-off and insignificant.

 

Most reporters accept this response. For instance The Economist.

Let up put this into context.

Consider three (hypothetical) scenarios form the UK.

1. The police investigation into a (possibly) racially-motivated murder is flawed, leading to the acquittal of the accused. The Chief Superintendant blames it on lack of funds for staff training, having previously said race was not a motive.

2. A profitable, listed company goes bust as a result of long-term massaging of the figures. This occurs three months after a respected accountancy firm signs off the annual accountants with no adverse comments. A senior partner says that the auditors were denied access to certain data, but had a signed note from the CFO that another accountancy firm had reviewed that data as part of a management-consultancy exercise. The CFO claims that the company was sound, and has an independent audit to prove it.

3. A highly-rated hospital turns out to have significantly higher death-rates than the average. The hospital chief executive says that it is due to having to cut back on the cleaning, having previously stated that the figures were flawed and politically biased.

In every case, the press and opposition politicians, would be asking for independent enquires (to assess the extent of the problem and to make preventative recommendations for the future), the suspensions of those involved and the sacking of the top person in the organization. So why no such questions, when there is a serious procedural failing in (probably) the most important scientific report of all time? A report that could adversely impact the living standards of billions of people should be to the highest scientific standards ever achieved.

It is not a minor mistake to misquote and embellish a tract from a campaigning group – and then say the forecast is highly likely, without any statistical analysis. This report is written by top Phd’s in their field, not first-year undergraduates. They should know how to assess reports, and draw accurate conclusions based on the evidence.

Further, whilst it is right for the UN IPCC to recognize the error and apologize, it is not for that organization to say, without internal investigation, that this is an isolated incident.

There should be an independent audit of all the report, to make sure that it is uniformly based on clearly-defined scientific standards. The starting point of an audit should be an evaluation of the laid-down scientific standards, and the documented internal control procedures for evaluating the adherence to those standards.

Areas of a full audit might include:-

  1. That the report is a balanced assessment of the current state of the science, at least noting competing views where it comes down on one side.
  2. Any statistical probabilities to be verified by trained statisticians.
  3. Assumptions, where made, should be identified.
  4. Measurement errors compared to the changes measured.
  5. The robustness of conclusions over differing timescales. For instance the correlations between increase in CO2 and temperature changes should not be over a defined period, but should test for a decade
  6. Gaps in the knowledge identified and put into the context of known factors and measurement errors.
  7. To note the relative standpoints of lead authors of parts of the report in respect to the established science. That is to whether they have recent, novel or controversial standpoints. And to the extent to which this influenced their review comments.
  8. For recently published peer-reviewed articles central to the aspect, whether it firmly establishes new ground in the debate.
by Kevin VS Marshall (Manicbeancounter) on 23/01/2010  •  Permalink
Posted in Beancounting Methodology, Climate Change, Global Warming, Science & Non-science

Posted by Kevin VS Marshall (Manicbeancounter) on 23/01/2010

https://manicbeancounter.com/2010/01/23/himalayan-glaciers-the-unipcc-response-and-an-inquiry/

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