Conservationist claims bias at the IPBES

Mr Clive Hambler, a conservationist and ecologist at the University of Oxford, has recently given evidence to the Committee for Academic Freedom of bias towards mainstream climate narratives in top academic institutions.  

Mr Hambler is notable for his discovery of the similarity between terrestial and freshwater extinction rates, and helped create the first conservation courses at the University of Oxford.  

Hambler’s first criticism concerns the IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services). The IPBES is an organisation similar to the IPCC, but with a focus on biodiversity and ecology. In 2019, the IPBES published its first Global Assessment Report, in which it ranked climate change as a greater threat to biodiversity than invasive species (Summary for Policy Makers, page 11).  

Hambler notes that this view is controversial among conservationists – a fact which the report failed to note. Further, that the methodology of a literature review to assess threats to biodiversity is “risky and subjective”. In addition, Hambler claims that the report “bizarrely” played down the widely held view amongst conservationists that invasive species constitute a dominant threat to species. Hambler suggests that these failings in the report may be the product of a bias in favour of stressing the negative effects of climate change, as opposed to the negative effects of other factors, on biodiversity. Hambler’s criticisms, which were given to the US congress, can be viewed here

Mr Hambler has also described evidence of potential bias at the preprint server arXiv. The preprint server allows scientists to share their work for discussion, prior to formal publication. Mr Hambler submitted a paper in which he showed that sea ice extent correlates extremely strongly with the seasonal fluctuations in the atmospheric levels of CO2. Seasonal fluctuations in CO2 levels are currently thought to be due to greater levels of vegetation in the northern hemisphere compared to the southern hemisphere. When it is summer in the northern hemisphere, more CO2 is absorbed from the atmosphere than in winter. Current calculations for the changes required for the world to reach net zero in CO2 emissions rely on this understanding of the seasonal fluctuations in CO2 levels. Mr Hambler’s results provide strong evidence that the seasonal cycle of CO2 is more likely to be driven by high-latitude ocean phenomena than by greater vegetation of the northern hemisphere. Thus, they suggest that current calculations of what is required to reach net zero may be significantly inaccurate. Achieving net zero may be substantially more difficult than it is thought to be in prevailing scientific narratives.  

Mr Hambler’s work was rejected for preprint publication by arXiv on the grounds that it did “not contain sufficient original or substantive… research”. This claim of arXiv appears to be transparently weak. Mr Hambler’s evidence and conclusion that the seasonal cycle of CO2 is more likely to be driven by high-latitude ocean phenomena than by seasonal forests is wholly original, and highly relevant to society. Hambler’s paper was later published by the International Journal of Atmospheric and Oceanic Sciences. Mr Hambler claims that arXiv’s rejection of the paper for preprint publication may be evidence of a bias at arXiv in favour of work that does not challenge prevailing narratives in climate science.