Willie Soon and Bob Carter are coauthors on a new paper in Nature Geosciences by Yan et al. It looks like an interesting paper exploring the movements of the intertropical convergence zone between China and Australia over the last millennium using palaeohydrology records and relating this to solar activity. Unlike many papers looking for evidence of the impact of solar variability on the Earth’s climate in palaeo-data, it is not immediately obvious that this paper is flawed. So I’m going to ask some critical questions about this paper.
Papers published by journal in the Nature group all include author contribution statements.
H.Y. designed the study and wrote the manuscript. W.W. contributed to the section discussing climate model results. W.S. contributed significantly to improvements in the manuscript. Z.A., W.Z. and Z.L. contributed to discussion of the results and manuscript refinement. Y.W. and R.M.C. contributed to improving the English.
Contributing to the “discussion of the results and management refinement” could certainly merit coauthorship, whereas contribution “to improving the English”does not obviously merit coauthorship. Nature’s policies on coauthorship are not prescriptive
The author list should include all appropriate researchers and no others. Authorship provides credit for a researcher’s contributions to a study and carries accountability. The Nature journals do not prescribe the kinds of contributions that warrant authorship but encourage transparency by publishing author contributions statements.
so no foul there. But the Australian Research Council’s Code for responsible conduct of research has well defined criteria for authorship (Carter is Australian).
To be named as an author, a researcher must have made a substantial scholarly contribution to the work and be able to take responsibility for at least that part of the work they contributed.
Attribution of authorship depends to some extent on the discipline, but in all cases, authorship must be based on substantial contributions in a combination of:
- conception and design of the project
- analysis and interpretation of research data
- drafting significant parts of the work or critically revising it so as to contribute to the interpretation.
Substantial intellectual involvement is required.
How do the authors reconcile their inclusion of Carter as a coauthor for “improving the English” with this code of conduct?
Conflicts of interest
Yan et al (2015) make the following statement about conflicts of interest
The authors declare no competing financial interests.
Willie Soon has made this statement before. It turned out not to be entirely true.
Nature’s guidance to authors is clear.
… competing interests are defined as those of a financial nature that, through their potential influence on behaviour or content or from perception of such potential influences, could undermine the objectivity, integrity or perceived value of a publication.
They can include any of the following:
Funding: Research support (including salaries, equipment, supplies, reimbursement for attending symposia, and other expenses) by organizations that may gain or lose financially through this publication.
It is difficult to specify a threshold at which a financial interest becomes significant, … , so we offer as one possible practical alternative guideline: “Any undeclared competing financial interests that could embarrass you were they to become publicly known after your work was published.”
Since Willie Soon appears to be impossible to embarrass, perhaps he feels that the $1.2 million funding from the fossil fuel industry and speakers fees for attending the Heartland and Doctors for Disaster Preparedness meetings are below the necessary threshold. Would his coathors agree?
And so onto the science. The authors write
The Little Ice Age (defined as AD 1400–1850) was associated with low solar irradiance and high atmospheric aerosol concentrations as a result of several large volcanic eruptions.
strong volcanic eruptions have been detected during the LIA (that is, coinciding with the Maunder Minimum and Dalton Minimum)
Yet somehow the paper focuses only on the solar variability. Why?
How sensitive are the results to the choice of the amplitude of total solar irradiance variability? Yan et al set this to 0.25% rather than the smaller amplitude preferred by the IPCC.
Yan et al show differences in reconstructed palaeohydrology from a set of sites across a region stretching from Australia to China. They show that the northern and southern sites become drier during the Little Ice Age, whereas the equatorial sites become wetter. Site selection is a crucial component of any analysis of this type. What does Yan et al have to say about site selection criteria? Nothing. Nothing at all. Nothing about how good the chronologies are or about the confidence to which proxy variability can be attributed to hydrological change. The paper should not have been published without this information.
It might be fruitful to compare the geographic patterns in hydrological change that Yan et al find over the last thousand years with those reported by Tian et al (2013).
The latitudinal patterns reported by Yan et al do not seem so obvious in Tian et al’s compilation. So what criteria were used?