Summary: Today we look at a weakness in the latest IPCC report, that illustrates a larger problem in the climate sciences.
Other posts in this series about second order draft (SOD) of the Fifth Assessment Report (AR5) by the Intergovernmental Panel on Climate Change (IPCC).
Contents
- A weakness of the IPCC’s process
- This shows a far larger weakness in the climate sciences
- For More Information About Rising Sea Levels
(1) A weakness of the IPCC’s process
“The IPCC gets better” post lists some weaknesses of IPCC procedures, including this:
Mockton’s review also has long (very long) lists of peer-reviewed science overlooked by the IPCC (and ignored by the news media), because it ruins the narrative. This goes to the most serious criticisms of the IPCC: it’s narrow selection of sources, and blindness to many threads of research in the climate sciences.
… {this is} systematic misstating by IPCC authors of the climate science literature (eg, chapter lead authors often showcasing their own work and ignoring their critics). While just business as usual in academic science, the IPCC should not tolerable this when writing the foundation for high-stakes and high-cost public policy. It shows a lack of internal controls at the IPCC, and weakens their credibility — which is their greatest asset.
Let’s look at a high-profile example: rising sea levels — vivid, and so has become a widely used example of potential climate impacts (often hysterically so in the general media). Judith Curry (chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology) examines rising sea levels as am example of the IPCC exaggerating the conclusions of current research. This also illustrates a larger weakness in the climate change debate.
From Chapter 3 of the AR5 SOD (red emphasis added):
Two out of three reconstructions of GMSL (global mean sea level) from tide gauge data extending back to 1900 or earlier indicate non-zero acceleration. Estimates range from 0.000 to 0.013 [–0.002 to 0.019] mm yr–2, so it is likely that GMSL rise has accelerated since the early 1900s.
Prof Curry’s comment:
A fourth paper on this topic was recently published that was not referenced in Chapter 3 of the SOD {Gregory et al, below}. So the addition of one more paper to the literature without an accelerating trend (2 out of 4) implies, according to the IPCC reasoning about uncertainty, that acceleration of sea level trend is ‘about as likely as not.’
Under this line of reasoning, the addition of one paper to the literature can change the assessment from ‘likely’ to ‘about as likely as not.’ And since the Gregory et al. paper seems to be superior from a methodological perspective, a more sophisticated assessment process would weight this paper more heavily. It looks to me like the IPCC needs to change this particular conclusion (especially the confidence level) in view of this new paper by Gregory et al.
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My problems with the IPCC’s characterization of and reasoning about uncertainty are described in my paper Reasoning about climate uncertainty, and this particular case is a good example of the flimsiness of many of the confidence assessments, especially for data sets that have a low maturity level.
The paper is “Twentieth century global mean sea level rise: is the whole greater than the sum of the parts?“, J M Gregory et al, Journal of Climate, in press. Abstract:
Confidence in projections of global-mean sea-level rise (GMSLR) depends on an ability to account for GMSLR during the 20th century. There are contributions from ocean thermal expansion, mass loss from glaciers and ice sheets, groundwater extraction and reservoir impoundment.
We have made progress towards solving the “enigma” of 20th-century GMSLR — that is, the observed GMSLR has been found to exceed the sum of estimated contributions, especially for the earlier decades. We propose that:
- thermal expansion simulated by climate models may previously have been underestimated owing to their not including volcanic forcing in their control state;
- the rate of glacier mass loss was larger than previously estimated, and was not smaller in the first than in the second half of the century;
- the Greenland ice-sheet could have made a positive contribution throughout the century; groundwater depletion and reservoir impoundment, which are of opposite sign, may have been approximately equal in magnitude.
We show that it is possible to reconstruct the times eries of GMSLR from the quantified contributions, apart from a constant residual term which is small enough to be explained as a long-term contribution from the Antarctic ice-sheet. The reconstructions account for the approximate constancy of the rate of GMSLR during the 20th century, which shows small or no acceleration, despite the increasing anthropogenic forcing. Semi-empirical methods for projecting GMSLR depend on the existence of a relationship between global climate change and the rate of GMSLR, but the implication of our closure of the budget is that such a relationship is weak or absent during the 20th century.
(2) This shows a far larger weakness in the climate sciences
We’re told that climate science research is the basis for public policy decisions necessary to save the world But the climate science apparatus (data collection and analysis) are grossly underfunded. As in this example, where three studies provide the evidence for claims that the rate of sea level rise has accelerated. Fixing one New York subway station after Sandy will cost $600 million. How much is it worth spending to get reliable evidence on the rate at which the seas are rising?
Why are the people advocating massive public policy action to fight climate change not calling for massive research programs, beyond the garage-scale research of much climate science today — in which individuals or small groups tackle questions requiring large teams of multi-disciplinary experts? The most likely answer to that question tells us much about the debate. The warmistas have their answers, and have little interest in more research.
What needs more funding
Some examples of research programs in need for more funds, stat.
(a) The global climate surface measuring system is grossly inadequate. Even in the US, and the US has one of the best national networks. At the other extreme, coverage in Antarctica is sparse — and coverage of the Arctic Ocean is almost non-existent.
(b) We have few global sensors for less-familar problems. For example, sensors watching solar activity — and scientists studying the results — are grossly underfunded. As described in this article about space weather forecasting: “Are We Ready for the Next Solar Maximum? No Way, Say Scientists“, Richard A. Kerr, Science 26 June 2009.
(c) To understand the present and predict the future we need reliable data from paleoclimatology studies. The proxy data for reconstruction of historical climate data is absurdly poorly funded, considering the importance of the data. Again multi-disciplinary teams are needed — with third party reviews of sampling techniques (to avoid cherry-picking of samples or proxies), interpretation (e.g., interpreting the underlying signal in terms of precipitation or temperature), and analysis (e.g., to avoid over-emphasis on certain geographical regions or samples). Note: these are only indirect measures of temperature.
(d) These climate research programs should be coordinated, so that the gaps are filled and quality maintained through processes faster and more reliable than the routine academic mechanisms of peer-review.
(3) For More Information about rising sea levels
- An example of important climate change research hidden, lest it spoil the media’s narrative, 22 May 2009 — About rising sea levels
- About that melting arctic ice cap, 17 April 2010
- Fear or Fail: about the melting Greenland ice sheet, 24 May 2010
- Today’s good news, about rising sea levels, 3 June 2010 — Esp note the links to articles and studies!
- More about the forecast for flooded cities in the late 21st century, 16 October 2010
- Looking into the past for guidance about warnings of future climate apocalypses, 17 October 2010 — Two of James Hanson’s past predictions
- About the coming sea ice Armageddon!, 19 June 2012
- Shaping your view of the world with well-constructed propaganda, 21 June 2012 — About rising sea levels.
- Run from the rising waves! (The latest climate catastrophe scare), 27 June 2012
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