Why I Remain Uncertain about Global Warming and Climate Change

My apologies

My apologies in advance for my stream of consciousness presentation style. I prefer to think and express myself in crisp, succinct, relatively small sections, rather than any lengthy narrative prose. I do try to present material in some sort of rational order, building on previous sections, but too often I find that I simply have a lot of points to make but I cannot find any precise order to express those points.

Too long, I know, but thorough

I also have to apologize in advance for the extreme length of this paper — 236 pages, so far. What can I say — there’s a lot to say.

Work in progress

This paper is a work in progress. I considered it complete at the time I published it, meaning I didn’t have any additional material to include at that time, but new material and thinking can come up at any time and will be incorporated as seems appropriate.

Focus on causes of warming and climate change rather than impact of climate change

Many of the projected major impacts of climate change are too far down the road — decades, a century, or more — for me to be concerned with here. This paper will focus on causes of climate change, causes of warming, and any near-term impacts only.

Yes, scientists are doing the best they can

I don’t doubt that scientists are doing the best they can.

Yes, I have very high standards

Is that against the law — to have very high standards? If so, then I am guilty as charged.

I collect puzzle pieces, tidbits, and fragments

I make no claim to having a complete and detailed knowledge of all aspects of climate science and all details needed to fully and deeply comprehend the theory of global warming and climate change.


It is not my intention to persuade anybody about anything with this paper.

Terminology: Global warming and climate change

Are we talking about global warming or is it climate change? Or both? What is the proper terminology that fully and correctly refers to what we’re talking about?

  1. What is global warming?
  2. What causes global warming?
  3. What is the role of human activity in causing global warming?
  4. What is climate change?
  5. What causes climate change?
  6. Does global warming cause climate change?
  7. What are the impacts of climate change?
  8. What are the impacts of climate change on human activity?
  9. What can we do about global warming?
  10. What can we do about climate change?

Global warming vs. climate change

Global warming and climate change are clearly connected, at least in the minds of those who support the theory of global warming and climate change, but the two are conceptually distinct:

  1. Global warming is strictly about the heat and temperature of the atmosphere and oceans of the Earth, distinct from what impact that heating might have.
  2. Climate change is strictly about the impacts of atmospheric and ocean heating, regardless of how that heating occurred.

Anthropogenic global warming (AGW)

Just to clarify the terminology a little further, in popular parlance we casually refer to global warming, but the technically correct scientific term is anthropogenic global warming, or the acronym AGW.

Anthropogenic global warming and climate change

Just to make it crystal clear, when this paper refers to global warming and climate change it is referring to anthropogenic global warming and climate change, emphasizing the role of human activity.

What exactly do people really mean when they use the term “climate change”?

At least the semantics of the term “global warming” is clear — a rise in temperature (or heat.)

Scientific consensus: Earth’s climate is warming

Just for a baseline reference this section reflects the official federal government posture with respect to global warming and climate change, as reflected on the main government climate change consensus web page:

I accept the national and international political consensus, that global warming and climate change are real

As a practical matter, I accept the national and international political consensus, which presumes that global warming and climate change is real.

But I remain uncertain concerning the science behind the theory of global warming and climate change

When it comes to science, global warming and climate change is a theory, rather than a fact. Theories and facts are rather different.

Whose consensus?

Is there really a national or even global consensus on global warming and climate change?

  1. 71% Say most scientists believe global warming is occurring.
  2. 68% Believe global warming is caused by human activities.
  3. 62% Believe effects of global warming have already begin.
  4. 45% Worry a great deal about global warming.
  5. 42% Think global warming will pose a serious threat in their lifetime.
  1. 66% of Democrats.
  2. 45% of independents.
  3. 18% of Republicans.

Pascal’s wager

Mathematician and philosopher Blaise Pascal theorized that it would be better to bet on the existence of God even without proof since the downside of the bet was minimal and the upside was very large, and the downside of betting wrongly against God’s existence would be catastrophically negative.

  • Modest to moderate efforts to reduce our emissions of greenhouse gases is not likely to cause any significant harm, so if people really want to do that, I won’t object too strongly, provided that the economic cost is minimal.

The Precautionary Principle

Plainly put, the Precautionary Principle requires that a course of action be scientifically proved to be harmless before that action is pursued.

  1. Ban use of fuels and forms of human activity unless and until they can be scientifically proven to be harmless to the environment, especially the climate.
  2. Ban mitigation measures, such as geoengineering, unless and until they can be scientifically proven to be harmless to the environment, especially the climate.

I am not a scientist, but…

Big disclosure up front:

  1. I was always interested in science as a child.
  2. Science was my favorite class in high school. Until I discovered computers, that is.
  3. I went to an engineering and science college.
  4. I received a Bachelor of Science (BS) degree, although my focus was computer science rather than physical science.
  5. I also received a Master of Science (MS) degree in Computer Sciences from the Electrical Engineering department, simultaneous with my undergraduate degree.
  6. I took some science classes in college — two years of chemistry and two years of physics, including labs.
  7. As a freshman in college I actually had a professional-grade K&E Keuffel & Esser slide rule for labs and taking tests in science classes. Electronic calculators were still too new that year.
  8. I was never strongly interested in numbers and math per se, preferring computer science and processing of symbols and text.
  9. Back in the 1980’s and 1990’s a took an interest in radiation, chemistry of nuclear materials, aerosols, and health physics, in large part due to the fact that I lived in Boulder, Colorado, ten miles from a major nuclear weapons plant. I learned a lot about the science, on my own.
  10. I’ve had a strong interest in space, space travel, stars, and astrophysics for many years.
  11. I’ve had a strong interest in understanding the science behind global warming and climate science for over a decade now, inspired in large part by the hysteria that arose on both sides in response to Michael Crichton’s book State of Fear in 2005, in addition to what I felt was a distinct non-scientific tone in Al Gore’s movie An Inconvenient Truth in 2006. Both efforts inspired me to understand the science better.
  12. In recent years I have taken a strong interest in physics, especially quantum mechanics.

Is global warming and climate change a hoax?

No, I do not hold the belief that global warming and climate change is a hoax.

Is global warming and climate change beyond dispute?

As a matter of principle, I don’t believe that any theory or belief, scientific or otherwise is ever beyond dispute. Or beyond debate.

Am I a climate change denier?

This gets a little trickier, so I have to give multiple answers?

  1. No, I do not believe that climate change is not happening.
  2. No, I do not deny that the climate is changing.
  3. No, I do not believe that the theory of global warming and climate change must be false.
  4. No, I do not hold a strong belief that the theory of global warming and climate change is false.
  5. But… I do not hold a strong belief that the theory of global warming and climate change is true either.
  6. I do hold a weak belief that the theory of global warming and climate change might be true. Yes, I think it is possible.
  7. Yes, I deny that I have a strong belief that the theory of global warming and climate change is true.

Yes, the theory of global warming and climate change could be true

That’s my bottom line position at this stage, that there is not strong science either way, but since there is no strong science proving that the theory of global warming and climate change must be false, I am forced to accept that the theory could be true.

I believe there is a 20% to 60% chance that the theory is true

Given what I do know, I would say that there is between a 20% and 60% chance that the theory of anthropogenic global warming and climate change is true.

I am a denier of the certainty of global warming

Although I recognize that the theory of global warming and climate change could be true, I nonetheless feel compelled by reason to deny that the theory is as true and certain as its proponents assert.

Could there be global warming without human activity and carbon dioxide as the cause?

One of the core difficulties of the theory of global warming and climate change is that beyond simply asserting that the planet is warming and the climate is changing, it places three very significant hurdles or assertions in the way of accepting the theory:

  1. That only human activity is to blame for the vast bulk of the warming.
  2. That only carbon dioxide is to blame for the vast bulk of the warming.
  3. That only combustion of fossil fuels by humans is to blame for the vast bulk of the warming.
  1. Some degree of warming is occurring.
  2. Human activity is responsible for some portion of that warming.
  3. That warming is causing some changes in the climate.

Could there be anthropogenic global warming without carbon dioxide as the cause?

Now I will rerun the previous section but with one key difference: an acceptance that there is anthropogenic global warming, but without demanding that carbon dioxide or the combustion of fossil fuels is necessarily the cause.

  1. That only carbon dioxide is to blame for the vast bulk of the warming.
  2. That only combustion of fossil fuels by humans is to blame for the vast bulk of the warming.
  1. Some degree of warming is occurring.
  2. Human activity is responsible for some portion of that warming.
  3. That warming is causing some changes in the climate.

Could human activity be heating the climate directly?

Even if you accept that human activity is causing the planet to warm, could that warming be occurring without the necessity of carbon dioxide and other greenhouse gases as the primary cause?

  1. Combustion of fuels, whether fossil or not, generates heat, a lot of heat.
  2. We use some of that heat as energy, to drive our electricity, lighting, machines, air conditioning, and heating within our homes and buildings.
  3. The process of generating electricity and energy is not 100% efficient. A lot of energy is lost, in the form of heat released into the environment, whether up a stack or through poorly insulated walls, directly into the atmosphere, or via heated water into rivers that flow into the ocean.
  4. And even when electricity and energy generation is efficient, that electricity and energy is used by lights, motors, air conditioners, and heaters, and in the process is turned into heat which is in turn released into the atmosphere.
  5. Factories use lots of energy, releasing heat into the environment.
  6. Wastewater released into rivers tends to be warmer than the current water temperature, then either evaporating and transferring heat into the air, or flowing into the oceans.
  7. Cars, trucks, buses, trains, planes, boats, and ships are all releasing copious amounts of heat into the atmosphere.
  1. Heat released directly into the atmosphere and waterways (and hence the oceans.)
  2. Greenhouse effect warming caused by the combination of heat directly released by human activity and additional water vapor that that direct heating enables.
  1. Direct from carbon dioxide or other non-water vapor greenhouse gases.
  2. From additional water vapor due to warming directly attributable to carbon dioxide and other non-water vapor greenhouse gases.
  3. From additional water vapor due to direct heating of the environment by human activity.
  4. From direct heating of the environment by human activity.

Am I an employee of an oil (or coal!) company?

No, I am not employed by any oil (or coal) company or any other company involved with the production, distribution, processing, or consumption of fossil fuels of any sort.

Am I a shill for the oil companies?

No, I don’t any sort of connection to any oil company or any company that has interests in fossil fuels.

Do I have investments in oil companies?

No, I don’t have even a single penny invested in stocks or other financial instruments related to oil companies or any company that has interests in fossil fuels.

I am a Tesla shareholder

I do own stock in Tesla, the electric car company. Part of that was an investment in Solar City, which was merged into Tesla in 2016.

I am a First Solar shareholder

I do own a very small amount of stock in First Solar, which manufactures solar power modules and panels, and operates solar power plants.

Do I have any motivation for disproving global warming or climate change?

No, I don’t have any motivation for disproving the theory of anthropogenic global warming and climate change. Not the slightest.

I have no stake in the debate

As I just noted, I have no vested interest in whether the theory of global warming and climate change is eventually proven to be true or eventually proven to be false.

Science communicators

Sure, the general public really does need science communicators, and science writers to gain some vague understanding of science, but I’m not one of those people who needs such translation or interpretation.

Two science communicators: Neil deGrasse Tyson and Bill Nye

Two of the highest profile and most popular science communicators are Bill Nye and Neil deGrasse Tyson.

Science communicator emeritus: Carl Sagan

Probably no single individual has epitomized the role of a science communicator to the degree of Carl Sagan, “astronomer, cosmologist, astrophysicist, astrobiologist, author, science popularizer, and science communicator in astronomy and other natural sciences. He is best known for his work as a science popularizer and communicator.

My aversion to emotional rhetoric and moralistic preaching

If there’s one thing that bugs me more than anything else, it is lofty, emotional rhetoric and fiery, moralistic preaching for matters which should be focused on simple facts and sound, rational, dispassionate reasoning.

I’m appalled by politicized scientists

Scientists are supposed to be special, kept separate from the messy, dirty, confusing, and distorted world of politics, and focused on reason rather than passion, emotion, and religious, ideological, political, or moralistic posturing.

The scientifically illiterate pontificating on matters of science

I’m no scientist or expert on science, but I do consider myself scientifically literate, meaning that I know more than a little about science, I read a lot, I understand data and analysis, and can navigate my way through charts, tables, raw data, and an occasional scientific paper.

Global warming and climate change is now 99.99% a sociopolitical matter and only 0.01% about science

Sadly, what used to be strictly a matter of science has now been so politicized that is is overwhelmingly a sociopolitical matter and very little of the actual science is even relevant anymore.

Can any science ever be “settled”, “indisputable”, “beyond dispute”, “beyond debate”, or “unequivocal”?

Those are sociopolitical characterizations, not scientific characterizations.

Rhetoric, emotion, passion, fear, anger, and morality

I am vehemently opposed to any public policy that is based in any way on:

  • Rhetoric
  • Emotion
  • Passion
  • Fear
  • Anger
  • Morality

My passion for dispassionate reason

I don’t believe that all matters can be reduced to strict mathematical logic per se, but I am focused intensely on reason. Dispassionate reason. Stripped of any rhetoric, emotion, passion, fear, anger, or morality.

My dispassion for narrative and storytelling

Many people thrive on storytelling and narrative, but I’m not one of them. I want facts and dispassionate reason, not passionate rhetoric and narrative.

Narrative rather than evidence or reasoning

In short, I consider that narrative, dense with emotional and moralistic rhetoric is a poor substitute for solid evidence and sound reasoning.


I have found that a lot of public comments about global warming and climate change are mere posturing, tending more to stake out a sociopolitical position than to enlighten others with true science.

Weaponizing science

Science should be a source of truth and enlightenment, not social and political power.

My loyalty is to science, not scientists

Having an analytical background, I have an intense appreciation for carefully-reasoned principles, data, and hard-core analysis.

Science — Actual science, real science, natural science, physical science, hard science

When I use the term science, I mean traditional natural science, physical science. What I call hard science. That consists primarily of:

  • Physics
  • Chemistry
  • Thermodynamics
  • Biology
  • Physiology
  • Astronomy
  • Geology
  • Oceanography
  • Classical meteorology
  • Mathematics
  • Statistics
  • Social science
  • Medicine
  • Psychology
  • Sociology
  • Modeling
  • Computer science
  • Speculation separate from empirical validation

Three requirements for scientific theories

Regardless of the field of science, a scientific theory has to satisfy three essential requirements:

  1. It must fully explain the phenomenon under study.
  2. It must fully account for past observations of the phenomenon.
  3. It must be capable of predicting the outcomes for future instances of the phenomenon.

Empirical validation

The greatest theoretical explanation in the world is worth nothing without empirical validation.

Anecdotal evidence is not proof

Anecdotes can certainly help to illustrate a principle, theory, or proposition, but do not constitute proof of a principle, theory, or proposition.

My model of models

I’m no card-carrying scientist, but from my own technical and analytic background I have firm ideas about the general structure of any modeling effort. I see any model as requiring these components:

  • The phenomenon being studied and modeled.
  • The science that explains the phenomenon.
  • The model being proposed that represents the phenomenon and satisfies the science.
  • Assumptions that are needed.
  • Assertions that are being made.
  • The math needed to define the science.
  • The math needed to define the model.
  • The algorithms needed to perform the math given input data.
  • The software code needed to implement the algorithm.
  • The results of running the software code over given input data.
  • A quality assurance (QA) effort to validate that the results confirm to the algorithm, math, model, and science.
  • Analysis of the results. What does it show? Is everything expected? Any new phenomena indicated?
  • Empirical validation of the results. Past actual measurements comport with modeled data. Predicted data comports with new measurements.
  • Publicly accessible datasets. All data used in analysis should be publicly accessible.

Open science process

Private, hidden, or proprietary science is not the preferred approach to any science. And it is not acceptable if the science is to be used as the basis for setting public policy.

  1. The full narrative description of the phenomenon under study, including its scope and context.
  2. The full description of the science being proposed.
  3. The full description of any models being proposed.
  4. The assumptions made.
  5. The assertions made.
  6. The math used.
  7. The algorithms used.
  8. The computer software used.
  9. Records of the genesis, rationale, proposals, requirements, specifications, and process used in development of all of the above. No private communications; records must be kept of all communications.
  10. Test data used.
  11. Records of QA, testing, and development of the math, algorithms, and software.
  12. Records of iteration in the development of all of the above.
  13. All datasets used at any stage of the process.
  1. To allow other scientists to reproduce the results.
  2. To allow the public and any interested parties to examine the process to understand how the science was developed in order to achieve some level of confidence in the science.

Transparency of science and data

Transparency is essential for credibility and confidence. It allows those of us outside the process to assess for ourselves what is going on behind closed doors.

My loyalty is to hard science

I am not persuaded by:

  1. Social science
  2. Rhetorical argument
  3. Narrative
  4. Emotional appeals
  5. Moralistic lecturing
  6. Appeals to faith — even to faith in scientists

Appeals to faith — even faith in scientists

I continue to be amazed at how many people seem to reject reliance on reason, their own reason, leaning very heavily on faith, even if it is faith in scientists, but more commonly it is faith in environmental and sociopolitical ideology.

Curious that there are no major universities with climate science or climatology departments

How can this be? Not a single one of the major, top universities in America has a standalone department focused on climatology or climate science. I mean, if climate science were as significant as proponents claim, surely it would warrant its own department.

Climate science or climatology does not appear to be a distinct, recognized field of science

Maybe that’s the reason that top universities in America do not have a standalone department of climatology or climate science — that it isn’t recognized as a standalone field.

How knowledgeable is the average climate scientist about all of climate science?

Individual scientists may indeed be very knowledgeable and maybe approaching absolute certainty in their specific, narrow area of expertise, but how much do they know about all of the many other areas of climate science?

Physics and climate science

I find it disturbing that so little of the discussion fails to link climate science and climatology to physics, which is where the real science, the behavior of gases, liquids, and movement of energy, belongs.

Is it climate science or climatology?

Why do we have two separate terms for the same thing? Are climate science and climatology the same thing or are they different in some way? Are the two terms exact synonyms or not? There are no good answers that I can find.

Two guys: Al Gore and Michael Crichton

Besides the many individual scientists involved with the theory of global warming and climate change, I’ll oversimplify the debates down to two individuals:

  • Al Gore — promoted the theory as U.S. Senator and Vice President and featured in the movie An Inconvenient Truth.
  • Michael Crichton — criticized the theory in his novel State of Fear.

Michael Crichton’s State of Fear

I do have to admit that Michael Crichton’s book State of Fear did have a significant impact on my own thinking.

Al Gore

I have such mixed views on former Vice President Al Gore.

Two more guys: James Hansen and Bill McKibben

Dr. James Hansen is a true climate scientist, known for his work on global temperature and global warming at the NASA Goddard Institute for Space Studies in New York City and a professor at Columbia University.

I’m with Freeman Dyson

Back in 2007 I read an essay entitled “Heretical Thoughts About Science and Society” in Edge written by Freeman Dyson, Professor Emeritus at Princeton’s Institute of Advanced Study. A theoretical physicist and mathematician. A really smart guy. Never got a Nobel, but got plenty of other prizes. The essay raised several interesting questions about global warming that got me thinking.

Is human activity changing the climate?

Maybe. Possibly. Hard to say.

Hasn’t climate always been changing?

Again, just to highlight the semantic confusion, that so many people are not being clear when they should be referring to anthropogenic climate change due to emissions of carbon dioxide from human activity.

Is climate changing?

Just to capture all these thoughts concisely in one place.

Is it science or a matter of faith?

Invariably, when I ask someone why they believe in climate change they usually have some other answer than to refer to actual science.

Since when is the truth of science determined by polls?

At least when I was in school, polls were never cited as a rationale for accepting a scientific law, proposition, fact, or other form of truth.

Is it 97% of scientists or 32%?

Here’s part of the abstract from one of the papers that is touted by NASA as supporting the assertion that 97% of scientists believe in global warming and climate change, from 2013:

Is it 97% or 63%?

That cited paper discussed a second part of their work where the authors of papers self-rated their belief about anthropogenic global warming (AGW):

  • 62.7% of all papers endorse AGW.
  • 35.5% of all papers take no position on AGW.
  • 1.8% of all papers reject AGW.
  • 62.7% of all respondents endorse AGW.
  • 34.9% of all respondents take no position on AGW.
  • 2.4% of all respondents reject AGW.

Is it 97% or 9%

Notice that not all scientists responded to the survey:

Other polls and surveys of scientists

I won’t bother delving into other surveys and polls of scientists. One was enough for my purposes.

Does an opinion count as science?

Hey, scientists are people too, so they are certainly entitled to have their own opinions, but does an opinion count as science just because the holder of that opinion is a scientist? I don’t think so.

Final word on the 97% consensus

Just to summarize my concerns on polls and surveys and so-called climate consensus studies in general:

  1. What field of science ever required “consensus studies”?
  2. Seriously, what % of scientists are qualified to judge fields outside of their own niche?
  3. It’s easy to say they believe or take a position, but do they offer scientific justification for such a belief or position? Are they proving that position or simply accepting it?
  4. What % are true climate scientists, rather than having a peripheral interest in the area?
  5. What % of so-called consensus has anything to do with the core issue of causal relationship between carbon dioxide and warming?

Scientists are people too

Scientists certainly have a special expertise in their area of specialty, but they are people too:

  1. Subject to human nature.
  2. Capable of error.
  3. Capable of getting carried away by enthusiasm.
  4. Capable of bias.
  5. Capable of being bullied.
  6. Capable of being conned.
  7. Have egos.
  8. Huge very strong egos.
  9. Have hubris.
  10. Can be embarrassed.
  11. Can be arrogant.
  12. Can be elitists
  13. Entitled to have personal opinions.
  14. Entitled to have political beliefs.
  15. Entitled to pursue sociopolitical agendas.
  16. Entitled to pursue protection of the environment “at all costs”, if they choose.

Concern about egos and embarrassment

As noted previously, scientists are people too, so I have concerns that their egos and risk of embarrassment may be getting in the way of their objectivity.

Scientists believe…

One last time… I don’t especially care what scientists may believe. Matters of science should be about science, not belief.

Political activation of scientists damages their credibility

Society needs science and scientists, but it also needs them to stick to their science, and to refrain from either using their science to pursue political aims or sociopolitical agendas, and to especially refrain from allowing political agendas and sociopolitical aims from poisoning or otherwise undermining their science, their only source of credibility.

Public opinion polls

I don’t put much faith or value in public opinion polls in general, and certainly not in terms of whether they validate any particular scientific belief.

Intergovernmental Panel on Climate Change (IPCC) as the central clearinghouse for science and narrative on the theory of global warming and climate change

For some people, former Vice President Al Gore is the central proponent of the theory of global warming and climate change. But from a technical, scientific, and governmental policy perspective, it is instead the Intergovernmental Panel on Climate Change (IPCC) which is the gold standard source for science and narrative on global warming and climate change — or what they call an assessment. In fact, I personally look to their assessments as a first source of information.

  1. Working Group I (WG1) — The Physical Science Basis
  2. Working Group I| (WG2) — Impacts, Adaptation, and Vulnerability
  3. Working Group III (WG3) — Mitigation of Climate Change
  1. Climate Change 2013: The Physical Science Basis.
  2. Climate Change 2014: Impacts, Adaptation, and Vulnerability.
  3. Climate Change 2014: Mitigation of Climate Change.
  4. Climate Change 2014: Synthesis Report.

IPCC Sixth Assessment Report cycle

Although the fifth assessment report (AR5) is the current assessment on global warming and climate change from IPCC, the successor report, the sixth assessment report (AR6) is underway. As the IPCC notes:

IPCC special report on global warming target of 1.5 degrees celsius (SR15)

To date, the target limit for global warming has been 2 degrees celsius, but scientists and policymakers seek to be more aggressive and reduce that limit to 1.5 degrees celsius. They are beginning work a special report, SR15. As the IPCC says:

What are the IPCC SAR and TAR?

SAR stands for the Second Assessment Report of IPCC, issued in 1995 and 1996.

United Nations Framework Convention on Climate Change (UNFCCC) treaty

The United Nations Framework Convention on Climate Change (UNFCCC) is the primary treaty or international law governing international efforts to address global warming and climate change.

Kyoto Protocol

See the UNFCCC section above.

Paris Agreement

See the UNFCCC section above.

Even the IPCC is not as certain as their headline claims say

In the Summary for Policymakers for their AR5 assessment report for Physical Science Basis, IPCC says on page 5:

IPCC uncertainty terminology and characterization

I’m extremely bothered when scientists feel the need to use overly-complicated terminology simply to express certainty and uncertainty. You either know for sure or you don’t. And if you don’t know for sure, say so. Or just say that you don’t know. If the situation is not that clear, then you have no business using exaggerated, hyperbolic language such as unequivocal, settled science, and beyond debate.

  1. Barely medium.
  2. Moderately medium.
  3. Solidly medium.
  4. Reasonably robust, or reasonably high.
  5. Solidly robust, or solidly high.
  6. Extremely robust or extremely high.
  1. What is the uncertainty assessment process?
  2. Is it pure consensus or a vote?
  3. How often is the assessment reviewed? Once per AR cycle?
  4. How early or late in the AR cycle is the assessment made?
  5. Who gets to participate in the assessment? Any scientists outside of the particular working group?
  6. What are the technical criteria for who may participate in the assessment?
  7. Is there any math involved in deriving these levels? If so, what is it?
  8. What variables or metrics are involved in that math? And how are those variables and metrics determined, derived, measured, and calculated?
  9. Or, is this all simply seat of the pants, subjective, and simply the judgment of the authors?
  10. Any sense of the degrees of bias that may be involved in these assessments?
  11. How much uncertainty is there about the uncertainty? Like an error bar on the confidence. Or maybe the current three levels of confidence are implicitly representing a significant degree of uncertainty about the uncertainty.
  12. What guidance and training are the authors given to assure some sense of rigor and consistency in the uncertainty assessment process?
  1. More gradations of certainty are needed. And some sort of error bar on the assessment of uncertainty.
  2. The method and process by which the uncertainty assessments were determined needs to be disclosed and detailed.
  3. There is simply too much uncertainty in the results of the IPCC. And the lack of sufficient gradations makes it more difficult to judge the judgments that IPCC provides.
  4. This whole level of rhetorical categorization of uncertainty seems unprecedented in science. What makes climate science special and requires this? Shouldn’t we wait until they no longer need anything less than extremely robust and extremely high confidence?

IPCC: It is certain that…

IPCC has generally been fairly good at using their uncertainty terminology, but occasionally they lapse into… certainty.

Continued in Part 2 of 4

Continue to Part 2 of 4.



Freelance Consultant

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