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New Paper Documents Main Reasons For International Controversy About The IPCC’s SR1.5 Report

London, 20 December: One of Europe’s most eminent climate scientists has documented the main scientific reasons why the recent UN climate summit failed to welcome the IPCC’s report on global warming of 1.5°C.

In a paper published today by the Global Warming Policy Foundation Professor Ray Bates of University College Dublin explains the main reasons for the significant controversy about the latest IPCC report within the international community.

The IPCC’s Special Report on a Global Warming of 1.5°C (SR1.5) was released by the Intergovernmental Panel on Climate Change (IPCC) in advance of the recent COP24 meeting in Katowice, Poland, but was not adopted by the meeting due to objections by a number of governments.

Professor Bates examines some key aspects of the SR1.5 report. He assesses if the IPCC report exhibits a level of scientific rigour commensurate with the scale of its extremely costly and highly disruptive recommendation that carbon emissions be reduced to zero by mid-century.

The paper concludes that such a level of scientific rigour is not present in the report. Specifically, SR1.5 is deficient in scientific rigour in the following respects:

● It departs from the IPCC’s Fifth Assessment Report in conveying an increased sense of planetary emergency without giving rigorous scientific reasons for doing so.

● It fails to communicate to policymakers a considerable body of important observationally-based research evidence that has accumulated since the Fifth Assessment which reduces the sense of a looming emergency.

● It fails to communicate important information made public by climate modellers since the Fifth Assessment regarding the empirical tuning of models to achieve desired results.

The paper concludes that, in view of these deficiencies, the SR1.5 report does not merit being regarded by policymakers as a scientifically rigorous document.

“There is much recent observational and scientific evidence that the IPCC report has failed to include and which supports a more considered mitigation strategy than the extreme and unrealistic measures called for in the SR1.5 report,” said Prof Bates.

In the foreword, Dr. Edward Walsh, the Founding President of the University of Limerick and former chairman of Ireland’s National Council for Science, Technology and Innovation said:

“The importance of adherence to the highest scientific standards on the part of the IPCC in its periodic reports can hardly be overemphasised. Governments rely on the scientific objectivity of these reports to make crucial decisions related to the economies of their countries and the wellbeing of their people. Policymakers should carefully reflect on the significant deficiencies identified in the report before considering implementing its recommendations.”

Deficiencies in the IPCC’s Special Report on 1.5 Degrees (pdf)


Prof Ray Bates MRIA
Adjunct Professor of Meteorology
Meteorology and Climate Centre
School of Mathematics and Statistics
University College Dublin
Belfield, Dublin 4, Ireland
t: +353-1-716 2421


* Peter Thorne:  Addressing stated concerns from Ray Bates around the SR1.5 

* Reply by Ray Bates to Peter Thorne’s blog post