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Climate Science: Assumptions, Policy Implications and the Scientific Method

re:look Aufriss

Adedamola Adedokun,

Dr. Philipp Lengsfeld

November 2020

Primary source: Testimony of Dr. Judith Curry, March 29, 2017. Climate Science: Assumptions, Policy Implications and the Scientific Method. Statement to the Committee on Science, Space and Technology of the United States House of Representatives.

The aim of this outline is to draw attention to the work of Dr Judith Curry on Scientific Method as it relates to Climate Change.

The above referenced paper is a testimony delivered to the Committee on Science, Space and Technology of the United States House of Representatives in early 2017. Dr. Judith Curry is the President of Climate Forecast Applications Network (CFAN) and Professor Emeritus of Earth and Atmospheric Sciences at the Georgia Institute of Technology. Her research interests span a range of topics in weather and climate. She has authored over 180 scientific papers, as well as textbooks on Thermodynamics of Atmospheres and Oceans, and Thermodynamics, Kinetics and Microphysics of Clouds. She is also a prominent public spokesperson on issues associated with the integrity of climate science.

In her testimony, Dr Curry expresses concerns over the vast oversimplification of the climate change problem and its solution. A major issue is the establishment of a scientific consensus on human-caused climate change by the climate community which has prematurely become a ruling theory. She stated that: “Premature theories enforced by an explicit consensus building process harm scientific progress because of the questions that don’t get asked and the investigations that aren’t undertaken.”

According to Dr Curry, there are factors that worsens the challenges in climate research. They include:

  • Expectations from policy makers.

  • Scientists who are playing power politics with their expertise and trying to silence scientific disagreement through denigrating scientists who do not agree with them.

  • Professional societies (that oversee the peer review in professional journals) who are writing policy statements endorsing the consensus and advocating for specific policies.

In addition, she addresses certain important issues relating to the problem of climate change and the scientific method.

Starting with the issue of scientific method for complex environmental systems, Dr Curry is of the view that scientific progress is enhanced by uncertainty, disagreement, and ignorance. She explains that: “‘Scientifically proven’ is a contradiction in terms – science does not prove anything. Scientists have a vision of reality that is the best they have found so far, and there may be substantial disagreement among individual scientists. Science works just fine when there is more than one hypothesis to explain something – in fact, disagreement spurs scientific progress through creative tension and efforts to resolve the disagreement. Science is driven by uncertainty, disagreement and ignorance – the best scientists actively cultivate doubt. Scientists do not concentrate on what they know, but rather on what they don’t know. Science is an ongoing process of revision that may be incremental, occur in fits and starts, or through an unexpected breakthrough.”

On the issue of the complexity of the climate system, global climate models are important tools in climate research since they represent complex aspects of the climate system. However, Dr Curry states that: “the notion of a correct or incorrect model is not well defined for models of a complex system. The relevant issue is whether the model ‘works’ and is fit for its intended purpose”. Also, while stating concerns about the usage of climate models, she argued that: “the current global climate models are not fit for the purpose of attributing the causes of recent warming or for predicting global or regional climate change on timescales of decades to centuries, with any high level of confidence.” The concerns include:

  • Predictions of the impact of increasing CO2 on climate cannot be rigorously evaluated for order of a century.

  • Failure of climate models to provide a consistent explanation of the early 20th century warming and the mid-century cooling.

  • Inability of climate models to simulate the magnitude and phasing of large-scale ocean oscillations on decadal to century timescales.

  • Insufficient exploration of climate model uncertainties.

  • Extremely large number of unconstrained choices in terms of selecting model parameters and parameterizations.

  • Evaluation of climate models against the same observations used for model tuning.

  • Concerns about a fundamental lack of predictability in a complex nonlinear system.

Dr Curry goes on to address the issue of cognitive biases in the science of climate change. She states that: “Simply, scientists are human and subject to biases. Further, they have personal and professional stakes in the outcomes of research – their professional reputation and funding is on the line. Assuming that individual scientists have a diversity of perspectives and different biases, then the checks and balances in the scientific process including peer review will eventually see through the biases of individual scientists. However, when biases become entrenched in the institutions that support science – the professional societies, scientific journals, universities and funding agencies – then that subfield of science may be led astray for decades and make little progress”.

Also, with regards to the climate science consensus, the author expresses concerns that “a scientific argument can evolve prematurely into a ruling theory if cultural forces are sufficiently strong and aligned in the same direction”.

Furthermore, “Premature theories enforced by an explicit consensus building process harm scientific progress because of the questions that don’t get asked and the investigations that aren’t undertaken. Overconfident assertions take away the motivation for scientists to challenge the consensus, particularly when they can expect to be called a ‘denier’ for their efforts and see their chances diminish for professional recognition and research funding. As a result of the enforced consensus, there is little independent thought that seeks to advance fundamental understanding or develop an independent aggregate understanding of how the climate system works”.

On the other hand, the author suggests that scientists can overcome their biases when they are being challenged and assessed for possible misguided conclusions. This can be done by themselves or others.

The author explains further that: “Science proceeds just fine with indefinite conclusions, disagreement and multiple hypotheses. In fact, science works best under the creative tension of competing hypotheses. Disagreement among scientists and support for rival hypotheses can arise from:

  • Insufficient and inadequate observational evidence.

  • Disagreement about the value of different classes of evidence (e.g. paleoclimate reconstructions, global climate models).

  • Disagreement about the appropriate logical framework for linking and assessing the evidence Overconfidence and differing assessments of areas of ambiguity and ignorance.

  • Belief polarization as a result of cultural pressures and the politicization of the science”.

Finally, the issues within the interface between climate science and policy are thoroughly addressed in the following excerpts:

“The climate community has worked for more than two decades to establish a scientific consensus on human-caused climate change, prematurely elevating a hypothesis to a ruling theory. The IPCC’s consensus-seeking process and its links to the UNFCCC emissions reduction policies have had the unintended consequence of hyper-politicizing the science and introducing bias into both the science and related decision making processes. The result of this simplified framing of a wicked problem is that we lack the kinds of information to more broadly understand climate variability and societal vulnerabilities. The politicization of climate science has contaminated academic climate research and the institutions that support climate research, so that individual scientists and institutions have become activists and advocates for emissions reductions policies. Scientists with a perspective that is not consistent with the consensus are at best marginalized (difficult to obtain funding and get papers published by ‘gatekeeping’ journal editors) or at worst ostracized by labels of ‘denier’ or ‘heretic.’”.

“‘There are a number of causes of climate change, including manmade causes. Climate science should work to understand all causes of climate variability change that are relevant on decadal to century timescales, and the impact of climate variability and change on societies and ecosystems.’ Such a framing would have arguably led to better understanding of the climate system and a much more rational approach in developing policies related to reducing our vulnerabilities to extreme weather and climate variations.”

“When the IPCC consensus is challenged or the authority of climate science in determining energy policy is questioned, these activist scientists and organizations call the questioners ‘deniers’ and claim ‘war on science.’ These activist scientists seem less concerned with the integrity of the scientific process than they are about their privileged position and influence in the public debate about climate and energy policy. They do not argue or debate the science – rather, they denigrate scientists who disagree with them. These activist scientists and organizations are perverting the political process and attempting to inoculate climate science from scrutiny – this is the real war on science.”

Author’s Conclusion and Recommendation:

The author concludes by reemphasizing that the challenges of climate research have been worsened by unreasonable expectations from policy makers, and the behavior of climate scientists and professional societies who due to their interests, attempt to immunize climate science from scrutiny and debate. Hence, this has led to “biased scientific research through politicization and funding priorities, as well as an undercut in the political process and dialog necessary for real solutions in a highly complex world”.

The author recommends that the social contract between scientists and government should be reconsidered, in addition to the development of a new model for policy-relevant science.

re:look conclusion:

This submission brilliantly addresses the issues present in climate science – the crux of which is the integrity and objectivity of climate research being compromised. The author expressed valid concerns and presented arguments which should be considered for the sake of the integrity of science, and an improved role of science in the policy making process.


References and Sources:

Testimony of Dr. Judith Curry, March 29, 2017. Climate Science: Assumptions, Policy Implications and the Scientific Method. Statement to the Committee on Science, Space and Technology of the United States House of Representatives.

Judith Curry -

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