The Climate Equivalence Principle: A Scientific Assessment

A Fellowship Discussion on Dr. Edwin Berry’s Challenge to Climate Science

Renaissance Ministries | March 14, 2026

“Buy truth, and do not sell it; buy wisdom, instruction, and understanding.”
— Proverbs 23:23

Introduction: A Neighbor’s Challenge

Dr. Edwin X Berry lives in Bigfork, Montana — about half an hour from Kalispell. He holds a PhD in theoretical physics from the University of Nevada, an MS from Dartmouth (where he studied under John Kemeny, who was a mathematics assistant to Albert Einstein), and a BS from Caltech. He was an NSF Program Manager for Weather Modification and has worked extensively in atmospheric physics.

He is also making an extraordinary claim: that the entire foundation of climate change science is wrong, and that human CO2 emissions contribute only about 18 ppm (parts per million) to atmospheric CO2, not the 130+ ppm that mainstream science attributes to human activity.

If he is right, the implications are staggering: trillions of dollars in climate policy are based on a scientific error, and the “climate crisis” is largely a fiction.

If he is wrong, his arguments — however sophisticated — could mislead many sincere people who are looking for reasons to resist the political agenda attached to climate science.

As Christians committed to truth, we must evaluate his claims carefully. This essay attempts to do so with scientific rigor and intellectual honesty.

Part I: Berry’s Core Argument — The Climate Equivalence Principle (CEP)

What Berry Claims

Berry’s argument centers on what he calls the “Climate Equivalence Principle” (CEP), which he presented at an international climate conference in Porto, Portugal in September 2018, and subsequently published in peer-reviewed papers in 2019, 2021, and 2023.

The CEP states:

Since human and natural CO2 molecules are identical, they must flow through the atmosphere at exactly the same rate. Mother Nature cannot tell the difference between a CO2 molecule from a car exhaust and one from the ocean.

From this principle, Berry argues:

IPCC’s fundamental assumption is wrong. The IPCC claims that human CO2 stays in the atmosphere much longer than natural CO2 — with a “residence time” of hundreds of years for human CO2 versus only about 4 years for natural CO2. Berry says this violates the CEP because identical molecules must behave identically.
The ratio in must equal the ratio out. If human emissions are only 3-5% of total CO2 inflow (with nature contributing 95-97%), then human CO2 can only be 3-5% of atmospheric CO2 — not the 32% the IPCC claims.
His “Physics Model” matches the Carbon-14 data. Berry uses the decay of Carbon-14 (from nuclear bomb tests in the 1950s-60s) as a tracer to determine how fast CO2 leaves the atmosphere. He claims his simple model replicates this data perfectly, while the IPCC’s “Bern model” cannot.
Human CO2 contributes only ~18 ppm. Based on his calculations, human emissions have raised atmospheric CO2 by only 18 ppm above the pre-industrial 280 ppm — not the 130+ ppm (bringing us to 410+ ppm) that is commonly attributed to human activity.

Berry concludes: “Checkmate!” The IPCC’s climate science violates basic physics, and all climate laws, regulations, and policies are therefore scientifically invalid.

Berry’s Credentials and Supporters

Berry has genuine credentials in atmospheric physics. His PhD thesis was cited in textbooks and recognized as a breakthrough. He was an NSF Program Manager. He has a CCM (Certified Consulting Meteorologist) designation and has served as an expert witness.

Richard Courtney, a UK climate scientist and professional reviewer, reportedly called Berry’s work “the ONLY true breakthrough in climate science since 1980.”

Hermann Harde, a German physicist, published similar conclusions in 2017, finding that human emissions contribute only about 15% to the CO2 increase.

Peter Stallinga published a paper in 2023 (in the journal Entropy) reaching similar conclusions about residence time versus adjustment time.

So Berry is not alone. There is a small community of scientists challenging the mainstream consensus on human CO2 attribution.

Part II: The Scientific Critique of Berry’s Arguments

The Core Distinction: Residence Time vs. Adjustment Time

The most important critique of Berry’s argument centers on a distinction he allegedly conflates: residence time versus adjustment time.

Residence time (also called “turnover time”): How long an individual CO2 molecule stays in the atmosphere before being exchanged with the ocean or biosphere. This is indeed short — about 4-5 years. The IPCC agrees with this.

Adjustment time (also called “equilibration time”): How long it takes for a perturbation (an excess amount of CO2) to be fully absorbed by the carbon cycle and for atmospheric levels to return to equilibrium. This is much longer — 50 to hundreds of years.

The key insight is that these are different things and can have different timescales:

Individual CO2 molecules may be rapidly exchanged between atmosphere and ocean, but if the ocean is also releasing CO2 at nearly the same rate, the net change is slow. The molecules are “swapping places” but the total amount in the atmosphere changes only gradually.

The Bathtub Analogy

Critics use a bathtub analogy to explain this:

Imagine a bathtub with water flowing in and out very rapidly (the faucet and drain are both wide open). The residence time of any individual water molecule is short — it quickly flows out the drain. But if you add a cup of water to the tub, how long does that extra water take to drain away? That depends on the net difference between inflow and outflow, not on the total flow rate.

If the faucet and drain are nearly balanced, even a small addition can persist for a long time.

Berry’s model, critics argue, treats the atmosphere as a simple “one-box” system with a single inflow and outflow. But the real carbon cycle has multiple reservoirs (atmosphere, surface ocean, deep ocean, land biosphere, soils) with different exchange rates and different response times. The simple model works for C-14 (which has essentially one source and decays radioactively) but fails for total CO2.

The Cawley (2011) Rebuttal

Gavin Cawley published a detailed technical response to similar arguments in the journal Energy & Fuels in 2011. He demonstrated that using a simple one-box model of the carbon cycle, you can derive:

A short residence time (~4 years)
A long adjustment time (~74 years)
A constant “airborne fraction” (~58%) — meaning about 58% of human emissions stay in the atmosphere
A very low proportion of anthropogenic CO2 molecules in the atmosphere

All of these are consistent with each other AND with the anthropogenic origin of the CO2 rise.

The key point: Short residence time and long adjustment time are not contradictory. They describe different phenomena.

Multiple Lines of Evidence for Anthropogenic CO2

The mainstream position is supported by multiple independent lines of evidence that Berry’s model does not adequately address:

1. The Ocean is a Net Sink, Not a Source

If the ocean were releasing CO2 (as Berry’s model would require to explain the rise from natural sources), the ocean would be outgassing CO2. But measurements show the opposite: the ocean is absorbing CO2 and becoming more acidic as a result.

Ocean pH has dropped by about 0.1 units since the industrial era (a 30% increase in acidity). This proves the ocean is taking in CO2, not releasing it. If nature were the source of rising CO2, we would expect the ocean to be releasing CO2 and becoming less acidic.

2. Carbon Isotope Fingerprints

There are three isotopes of carbon: C-12 (most common), C-13 (~1%), and C-14 (trace).

Plants preferentially absorb C-12 over C-13 during photosynthesis. Therefore, plant-derived carbon (and fossil fuels, which are ancient plants) has a lower C-13/C-12 ratio than the atmosphere.

If the rising CO2 were coming from fossil fuels, we would expect the C-13/C-12 ratio in the atmosphere to decline (more C-12 relative to C-13).

This is exactly what is observed. The decline began around 1850 and has accelerated — matching the pattern of fossil fuel combustion. This is called the “Suess Effect.”

Similarly, fossil fuels contain essentially no C-14 (it has decayed over millions of years). If fossil fuel CO2 is entering the atmosphere, the C-14/C-12 ratio should decline. This is also observed (setting aside the spike from nuclear bomb tests).

3. Oxygen Decline

Burning fossil fuels consumes oxygen: C + O2 → CO2. If the CO2 rise were from fossil fuel combustion, we would expect atmospheric oxygen to decline.

This is observed. The rate of oxygen decline matches expectations from known fossil fuel combustion rates.

If the CO2 were coming from ocean outgassing (as Berry’s model would require), oxygen would also be outgassing and atmospheric O2 would not decline (or would decline much less).

4. The Mass Balance

We know how much CO2 humans have emitted (from fossil fuel records, cement production, and land use change): approximately 1,500 gigatons of CO2 since 1850.

The observed increase in atmospheric CO2 is about 130 ppm, equivalent to roughly 275 gigatons of carbon (or about 1,000 Gt CO2).

This means approximately 58% of human emissions have stayed in the atmosphere, with the rest absorbed by ocean and land biosphere. This “airborne fraction” is consistent with carbon cycle models.

If Berry’s model were correct — if human emissions contributed only 18 ppm — where did the other 1,200+ Gt of human CO2 go? The ocean is absorbing CO2, not releasing it. The land biosphere is roughly neutral or a slight sink. There is no “missing sink” large enough to absorb this much carbon while nature simultaneously releases enough to account for the 130 ppm increase.

5. COVID-19: The Natural Experiment

During the COVID-19 pandemic in 2020, global CO2 emissions dropped by approximately 7%. Some skeptics argued that if human emissions were causing the rise, we should see an immediate impact on atmospheric CO2.

What was observed: Atmospheric CO2 continued to rise, but at a slightly slower rate (about 0.14 ppm less increase than expected in the Northern Hemisphere for February-April 2020).

Critics of Berry use this as evidence against him: “The reduction in emissions had no visible impact!” But the mainstream explanation is straightforward: A 7% reduction in a single year’s flow has a minimal impact on the accumulated stock of CO2. Just as slightly reducing the faucet flow doesn’t immediately drain the bathtub.

Berry’s supporters counter-argue that if human emissions were the primary driver, any reduction should have an immediate effect. But this conflates flow and stock.

Part III: Assessing the Arguments

What Berry Gets Right

The molecules are identical. This is true. A CO2 molecule from a car exhaust is chemically identical to one from ocean outgassing.
Residence time is short. The IPCC agrees that individual CO2 molecules exchange rapidly between atmosphere and other reservoirs (~4-5 years).
The IPCC models are complex and contain assumptions. All models contain assumptions. The question is whether those assumptions are justified.
Climate science has been politicized. This is undeniably true. The policy implications of climate science have led to enormous political pressure on all sides.
Skepticism is scientifically legitimate. The scientific method requires challenging assumptions and testing predictions. Berry is doing this.

What Berry Gets Wrong (or Fails to Address)

Conflating residence time and adjustment time. This appears to be the central error. The short residence time of individual molecules is compatible with long adjustment times for perturbations.
The one-box model is too simple. The carbon cycle involves multiple reservoirs with different exchange rates. A model that works for C-14 decay may not work for total CO2 perturbations.
Multiple independent lines of evidence. Ocean acidification, isotope ratios, oxygen decline, and mass balance all point to anthropogenic CO2 as the primary driver of the rise. Berry’s model does not adequately explain these observations.
The “missing sink” problem in reverse. If Berry is right, there must be a massive natural source of CO2 that somehow didn’t exist before 1850 and exactly correlates with human industrialization. What is this source? Berry points to ocean warming, but the ocean is measured to be absorbing CO2, not releasing it.
Publication venue concerns. Berry’s papers appear in journals like International Journal of Atmospheric and Oceanic Sciences (published by Science Publishing Group), which has been identified as a potential “predatory publisher” — a pay-to-publish outlet with less rigorous peer review. This doesn’t prove Berry is wrong, but it raises questions about why his work hasn’t appeared in top-tier climate journals.

The Expert Consensus

It is worth noting that Berry’s views are rejected by the overwhelming majority of climate scientists. The CO2 Coalition (a skeptic organization that generally opposes aggressive climate policy) has itself critiqued Berry’s work, publishing a paper in December 2024 that disagrees with his CEP argument.

When even climate skeptics reject an argument, it’s a significant data point.

However, consensus is not proof. The history of science contains examples where the consensus was wrong. The question is whether the evidence supports the consensus.

Part IV: A Christian Perspective

Our Commitment to Truth

As Christians, we are committed to truth. We believe that truth comes from God and that honest investigation of creation honors Him. We should not accept claims merely because they fit our political preferences, nor reject them for the same reason.

If Berry is right, we should follow the truth wherever it leads — even if it’s unpopular.

If Berry is wrong, we should not embrace his arguments simply because they oppose a political agenda we dislike.

The Problem of Motivated Reasoning

Climate change is deeply entangled with political ideology:

The Left often uses climate science to justify expanded government control, international agreements, and restrictions on economic activity.
The Right often resists climate science because it’s associated with this agenda.

Both sides are vulnerable to motivated reasoning — accepting or rejecting scientific claims based on their political implications rather than their evidence.

Christians should be especially alert to this temptation in ourselves.

Separating Science from Policy

Even if mainstream climate science is correct — even if human CO2 is the primary driver of atmospheric CO2 increase and contributes to warming — this does not automatically validate any particular policy response.

One can accept the science while rejecting:

Carbon taxes
International climate agreements
Restrictions on energy production
“Climate emergency” rhetoric

The science tells us what is happening. The policy question is what (if anything) to do about it, and that involves values, economics, and prudential judgment.

Conversely, one can reject the science while still supporting:

Clean air and water
Good stewardship of creation
Development of alternative energy sources
Reducing pollution

The policy questions are separate from the scientific questions.

What Should We Believe?

Based on my research, I offer the following assessment:

Berry’s CEP argument is probably wrong. The distinction between residence time and adjustment time appears valid, and Berry’s model does not adequately address it. The multiple independent lines of evidence (ocean acidification, isotope ratios, oxygen decline, mass balance) all point to anthropogenic CO2 as the primary driver of the rise.

However, climate science contains legitimate uncertainties. The magnitude of warming from CO2 (climate sensitivity) is still debated even among mainstream scientists. The role of feedbacks (water vapor, clouds, etc.) is uncertain. The predictions of future harm are model-dependent and contain substantial uncertainty.

The “catastrophist” narrative is probably overblown. While warming is real and human-caused, the apocalyptic rhetoric (“existential threat,” “climate emergency”) goes beyond what the science supports. Many climate scientists are uncomfortable with this rhetoric.

Berry’s broader critique of politicization is valid. Climate science has been corrupted by political pressure on all sides. The IPCC process is political as well as scientific. Skeptics have been marginalized and silenced in ways that violate scientific norms.

Recommendations for the Fellowship

Don’t dismiss Berry out of hand. He has credentials, he’s making specific scientific arguments, and he deserves a hearing. The fact that his view is unpopular doesn’t make it wrong.
But be cautious about embracing his conclusions. The scientific critiques of his argument appear strong. Multiple independent lines of evidence support the mainstream position.
Recognize the difference between science and policy. Don’t reject science because you dislike the policies that some want to build on it. Evaluate the science on its own merits.
Beware of motivated reasoning in yourself. It’s tempting to embrace arguments that support our political preferences. Ask yourself: Would I find this argument convincing if it led to a different conclusion?
Hold conclusions tentatively. Science is provisional. Today’s consensus can be tomorrow’s error. But we must act on our best current understanding while remaining open to revision.
Focus on what we can control. Whatever the truth about climate, we can practice good stewardship, live simply, reduce waste, and care for creation. These are Christian virtues regardless of climate science.

Part V: Questions for Discussion

On evaluating scientific claims: How should Christians assess scientific claims on complex technical issues where we’re not experts? What role should credentials, consensus, evidence, and argument play?
On motivated reasoning: Where might conservatives (or Christians) be vulnerable to accepting weak arguments because they oppose policies we dislike? Where might we be rejecting strong arguments for the same reason?
On Berry’s argument: Does the distinction between residence time and adjustment time make sense to you? Why or why not?
On the multiple lines of evidence: The mainstream position is supported by ocean acidification, isotope ratios, oxygen decline, and mass balance. Do you find these arguments compelling?
On policy: If the mainstream climate science is correct, what (if anything) should be done about it? What’s the relationship between scientific conclusions and policy recommendations?
On stewardship: What does biblical stewardship of creation require, regardless of climate science conclusions?
On neighborliness: Dr. Berry is our neighbor — literally. How should we engage with neighbors who hold strong views we may disagree with?

Conclusion: Humble Confidence

The climate debate is contentious, politicized, and technical. As Christians seeking truth, we should:

Be humble: We may not have the expertise to fully evaluate these arguments. We should hold our conclusions tentatively.
Be confident: We can follow evidence and reason to provisional conclusions. We don’t have to suspend judgment forever.
Be charitable: Those who disagree with us (on either side) may be sincere and well-intentioned. Disagreement is not the same as dishonesty.
Be discerning: Both sides have been guilty of exaggeration, motivated reasoning, and politicization. We should be alert to this on all sides.

My assessment: Berry’s CEP argument is probably wrong, but he raises legitimate questions about a science that has been heavily politicized. The mainstream consensus is probably correct on the basic question (human CO2 is driving the rise), but the catastrophist rhetoric is overblown.

What matters most is that we pursue truth honestly, wherever it leads — and that we act on our best understanding while remaining open to correction.

“The heart of the discerning acquires knowledge, for the ears of the wise seek it out.”
— Proverbs 18:15

Primary Sources:

Berry, Edwin X. “Human CO2 Emissions Have Little Effect on Atmospheric CO2,” International Journal of Atmospheric and Oceanic Sciences, 2019.
Berry, Edwin X. Climate Miracle, 2020.
Cawley, Gavin C. “On the Atmospheric Residence Time of Anthropogenically Sourced Carbon Dioxide,” Energy & Fuels, 2011.
Harde, Hermann. “Scrutinizing the carbon cycle and CO2 residence time in the atmosphere,” Global and Planetary Change, 2017.
Stallinga, Peter. “Residence Time vs. Adjustment Time of Carbon Dioxide in the Atmosphere,” Entropy, 2023.
Various IPCC reports and climate science literature.

Note: This essay represents an attempt to fairly assess competing scientific claims. The author is not a climate scientist and may have made errors. Feedback and corrections are welcome.

Climate Controversy – CEP