Ninety Nine Percent of all Conversations about Climate are Wrong

How I changed my mind about climate change. Again.

David Siegel
Jan 26 · 13 min read

M y name is David Siegel. I am concerned about the environment and the human enterprise. I wrote my first book on climate change in 1991. In 2015, I looked closer into the data and the messaging, and I changed my mind. I became a skeptic of catastrophic climate change and an advocate for science. Since then, I have written many essays and produced a one-hour movie showing the data. I continue to study climate about 20 hours a week, reading both peer-reviewed and non-peer-reviewed material (because of the biases of publication). Recently, I learned some things that changed my perspective yet again.

Government agencies, the popular press, and many others have portrayed the last 40 years as out-of-control warming and devastating weather events caused by man-made CO2 emissions. They predict catastrophic consequences in the decades to come.

I have been searching for the data that can definitively show that the earth is already warming as a result of man-made CO2. I want to go where the evidence is, and I’m willing to change my mind when I see evidence that supports a contradictory view. I haven’t seen it until today.

First, I’ll show two things I thought were important, then I’ll explain why they are red herrings causing people to look in the wrong direction.

Land Temperatures

To start this journey, I am still convinced that land-surface temperatures were much hotter in the 1930s than NOAA or Berkeley Earth portray and that you see in so many publications. I believe the narrative of cool 1930s and extremely hot 2000–2018 is simply false, the data has been tampered with, yet most journals and journalists rely on these graphs.

Journalists are busy people. Who has time to look into the data? Tony Heller has. Steve McIntyre has. Ross McKittrick has. Andy May has. Andy presents this graph in his essay, The U.S. National Temperature Index, is it based on data? Or corrections?

That’s a lot of correction. Note the slopes of the two lines.

In my view, you should correct the data, to account for the heat-island effect — the fact that so many long-term thermometers have been affected by roads and structures, motors and engines coming closer to weather stations over the past 80 years — causing thermometers to read hotter, especially at night. See my video on measuring temperature showing photos of weather stations that have been compromised. To see all the raw data, watch Tony Heller’s video showing the data from all 1,218 US Historical Climatology Network stations.

If you’re going to correct for the heat-island effect, you would a) remove the most affected stations from your data, and b) take the raw data and gradually start cooling temperatures slowly, starting around 1950. You wouldn’t adjust temperatures before that, and you wouldn’t adjust by increasing temperatures after that. Yet that’s exactly what NOAA and NASA do in preparing graphs for the UN and the public. They cool the past and warm the present, and they make up a lot of data, which raises serious questions from data scientists. In fact, John Goetz shows that all those NOAA, NASA, and Berkeley Earth data sets are gridded, which means that approximately 92 percent of Historical Surface Temperature Data is Made Up.

Not by hand, of course. They use interpolation and algorithms to create data. But when statisticians look at temperature data, they are astonished that “climate scientists” are so sure about their conclusions. Are we being told the truth by NOAA, NASA, and other government agencies? Follow the links, read the literature, and decide for yourself.

Equilibrium Climate Sensitivity

Second, I don’t believe that equilibrium climate sensitivity means anything. ECS is the amount of warming we can expect for a given doubling of CO2. It’s a theoretical number that drives climate models. ECS is logarithmic — doubling CO2 in the upper troposphere results in the ECS (number of degrees C) of warming; double it again and you’ll again get the same number of degrees of warming (not twice as many).

Judith Curry and Nic Lewis have written what I believe is the definitive paper on ECS, showing that any reasonable assumptions lead to a much lower ECS than the UN and NASA use in their models. In 2018, Curry and Lewis calculated their best estimate of ECS in their paper The Impact of Recent Forcing and Ocean Heat Uptake Data on Estimates of Climate Sensitivity, concluding that a reasonable median estimate is only 1.7 degrees C, at the lowest end of the UN IPCC’s range.

Will Happer of Princeton explains that, from a thermal perspective, the upper atmosphere is already mostly saturated. So adding more CO2 isn’t going to warm the earth very much. It’s like adding more sugar to a cup of coffee that already has four teaspoons of sugar.

Finally, as Willis Eschenbach points out, the whole ECS concept is probably wrong anyway. The oceans have a natural way of preventing overheating — storms form when the ocean surface gets too hot. Even NASA scientists have shown that the earth has its own regulating thermostat. Any thermostat-function would work against ECS by creating clouds to cool the earth rather than water vapor to trap heat.

So two things are not driving climate: a) downwelling solar radiation onto land, and b) how sensitive the upper atmosphere may or may not be to increased CO2. This means that despite politically-driven unrealistic inputs, and despite their failure to predict the past 30 years with any accuracy, the models are all invalid. Every one of them.

What Really Drives Climate

Before I break it down, I will quote Ed Zuiderwijk, who summarizes:

In its simplest form, the Earth is a heat-transfer system in non-equilibrium (but in a steady state) where heat (predominantly) enters in the equatorial regions and heat is (predominantly) lost at the poles. Inside, heat is transported from the tropics to the poles by atmospheric and oceanic currents, cooling the tropics and warming the polar regions.

Now let’s dive in.

Andy May, a retired petrophysicist and data scientist has convinced me that 99.9 percent of the thermal energy coming from the sun (including the greenhouse effect) and stored by the earth’s surface as heat goes into the oceans, not into the land or air. The oceans contain more than 99.9 percent of the thermal energy on the surface of the Earth, and their average temperature is only 4° to 5°C (40°F). On a calorie basis, the land stores essentially no heat, and the atmosphere stores less than 0.1 percent of the heat coming in. Oceans store the rest. Here are the key points that most people who talk about climate don’t understand:

  1. Land surface temperatures don’t measure climate, they measure weather.
  2. Ocean-surface temperatures have proven impossible to measure and don’t drive any long-term trends.
  3. The sun is the driver. The oceans are the medium through which the sun changes climate. On the scale of medium-to-long time periods, the mid-to-deep layers of our oceans drive ocean oscillations, trade winds, the gulf stream, the jet stream, and our climate, moving heat from middle latitudes toward the poles.
  4. However, when ocean surface temperatures get to a particular point, clouds and thunderstorms form and reflect sunlight, cooling the earth. The ocean surface serves as a thermostat to regulate temperature and return toward the mean. Clouds are a big reason most climate models run too hot.

Bottom line:

If you want to highlight or tweet that, here is the text:

Patterns in solar radiation over decades and centuries with various time lags drive oceans to change the climate. Nothing else matters.

Let me break it down.

Ocean Strata

First, let’s define what we mean by ocean temperature. There are three layers to measure and learn about:

  1. The skin is the area above and below the surface that is affected directly by incoming sunlight and conditions. It can range from ten meters on a windless sunny day to less than a centimeter on a cold windy night. Measurements of the sea surface are useless. Estimates using various methods do not agree. You can think of the sea surface and skin data as noise.
  2. The mixed layer is the layer from just below the surface until you see a 1/2-degree C drop in temperature. From a temperature-gradient perspective, the oceans are “hilly.” In some places, it’s 20 meters, in other places it’s 150 meters.

The mixed layer is responsible for almost 100 percent of climate changes that occur on the scale of a decade or more.

3. The deep ocean is below the mixed layer. It’s generally thought of as 500 meters and lower, usually down to around 4,000 meters. It’s very cold down there, and it takes a lot of energy to change that. From a temperature perspective, as you go deeper, you go further back in time. You can only measure significant differences by looking over centuries — data we do not have.


These last two layers drive our climate. If you hear that man-made CO2 is causing the arctic to warm, it can only be through currents bringing warm water north from the Equator. It could only have anything to do with manmade CO2 if that extra few parts per million had a direct effect on temperatures or movement in the mixed or deep layers decades to hundreds of years earlier. And you would have to explain why the arctic is heating but the antarctic is not. Can your theory do that?

Major ocean currents, mostly created by the Coriolis effect.

The oceans have been moving water around the globe for a long time, and our climate has varied dramatically as a result. The system is highly nonlinear. To say that man’s influence started in any particular year or can be seen in today’s climate is to create a mechanism that does not exist in reality.

The vast majority of the greenhouse effect comes from water vapor, which is driven by the oceans. A much smaller effect comes from naturally occurring greenhouse gases. A much much smaller effect may be added by the extra parts per million of CO2 in the upper troposphere. That effect may or may not be measurable in the oceans. Changes in ocean heat drive climate.

For ocean heat, we only have decent data since 2005, via the Argo buoy data. That’s the only meaningful data set of “warming” we have. Everything else is irrelevant because of the 99.9-to-0.1 ratio or because we measured ocean heat so poorly before Argo.

As far as we can tell from studying the past 15 years of ocean-buoy data, the oceans are increasing by 0.04 degrees per decade. Andy concludes:

The data we have suggests that the oceans are warming at a rate of 0.4°C per century. However, the ocean cycle-time is over 1,000 years and the record is only 15 years, so this is very speculative. However, if the oceans are truly only warming at a rate of 0.4°C per century, it seems very unlikely that the speculation about rapid and dangerous warming of the atmosphere is anything to worry about.

Here’s the smoking gun right here:

Courtesy of Willis Eschenbach

This is by far the best visualization of the best data we have of anything that can cause climate change. The land does not matter. The sun heats the tropics, some of it goes into the oceans, and that heat periodically moves toward the poles in various patterns we can measure but can’t yet explain or predict. Over the past 15 years, the Argo buoys have measured 0.06 degrees of ocean heat increase. This is is far more relevant than all the hockey-sticks and wiggly lines you have ever seen. Do you think that increase is driving storms, wildfires, drought, extreme weather, desertification, extinctions, sea-level rise, mass migrations?

Could we handle another 0.4 degrees of ocean warming in the coming century? It’s very likely we had that much in the previous century. But remember: the sun is variable. There are solar trends that could also cause cooling. Not much. And not quickly. And with some serious time lag, they would influence our future climate. I don’t see how CO2 plays much of a role in this.

It helps to remember what the UN wrote in their latest report (2018):

I no longer care much about surface temperature measurements, reports, analyses. I think they are noise. On the scale of decades, what counts is the top 500 meters of ocean minus the skin, and on the scale of centuries, what counts is the top 4,000 meters minus the skin. This is what drives ocean oscillation patterns, El Nino/La Nina effects, Atlantic and Pacific oscillations, the gulf stream, the jet stream, long-term temperature trends, even precipitation and the currents that are now warming the arctic. (Volcanoes and geothermal activity may also account for some of it, but man has nothing to do with those.)

If you think anthropogenic CO2 affects those mid-deep currents on the scale of the last 50 years, be sure to show your work. Nothing else can be driving climate.


For more than thirty years, I have been looking at the wrong graphs, talking about the wrong things, the wrong measurements, the wrong cause-and-effect theories. Talking about tundra, glaciers, permafrost, the troposphere, or the greenhouse effect is talking about the 0.1 percent. Talking about thermometer data is talking about the 0.1 percent. Assuming all that data has been fabricated and is completely wrong, or even assuming we have no idea what temperatures really were for the last 200 years, doesn’t matter much.

What matters is how oceans respond.

In short, 99.9 percent of our conversations on climate are wrong.

As Andy writes:

Anyone who thinks they know what the climate is doing today or will do ten years in the future just isn’t paying attention. It should be obvious to everyone that the oceans are the single most important driver of our long-term climate and the records that we rely upon to tell us what sea-surface and mixed layer temperatures are doing are not up to the task.

If you don’t get very serious about studying ocean heat, you are not studying climate.

I don’t know if this has changed your perspective, but if it has, be sure to ask whether what you are reading pertains to the 1 percent or the 99 percent. Ask how it affects ocean temperatures and currents. Ask whether they have actually understood the physics and cause-and-effect or whether they may have some other goal in mind and they are using climate arguments and scary pictures to get it.

If it doesn’t change your mind, I recommend writing down what exactly you would have to learn to change your mind. If the answer is “nothing,” then you have no reason to read another word on climate.

Write this on the wall, magazine and journal editors:

Suitable for highlighting and tweeting:

Any acceptable explanation of “global warming” has to show how extra CO2 in the upper troposphere causes the oceans to cause changes in climate. Period.

The last time I changed my mind about climate I wrote an essay that 300,000 people — more than a quarter of a million — read. How many will read this one? Please share it with others.

I haven’t covered all the details. I have left a trail of links to dive into. I leave you with selected research on this topic, so you can continue your own education.


The Argo web site

Tides and Currents — the interactive tide-gauge web site I feature in my video

Does Global Climate Change Require a Global Solution?

Sea Surface Temperature Measurement is a complete mess

Examining Ocean Temperature Data

The U.S. National Temperature Index, is it based on data? Or corrections?

Ocean Temperature Update

The Ocean Mixed Layer, SST, and Climate Change (read this if you don’t have time to read all of his work)

Willis Eschenbach’s animations of ocean heat.

Learning from the Argonauts

What do the Argo floats tell us?

NASA’s data shows ocean “conveyor belt” refusing to cooperate with global-warming models

A Small Margin of Error — critical thinking about ocean temperature measurement

Watts Available (this is the big one)

Boy Child, Girl Child (about el Nino/la Nina)

Under the Equator (a fascinating visual of el Nino/la Nina)

A Chain of Events (how ocean temperatures affect water vapor)

The NASA paper I mentioned: Mechanisms Regulating Sea-Surface Temperatures and Deep Convection in the Tropics.

David Siegel is a serial entrepreneur in Washington, DC. He is the founder of the Pillar Project. He is the author of The Token Handbook, The Digital Money Book, Open Stanford, The Culture Deck, Climate Curious, Shortfall, a climate blog, and The Nine Act Structure. He gives speeches to audiences around the world and online. His full body of work is at

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David Siegel

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Provocateur, professional heretic, slayer of myths, speaker of truthiness to powerfulness, and defender of the Oxford comma.

Science and Philosophy

Medium’s center for scientifically-informed content.

David Siegel

Written by

Provocateur, professional heretic, slayer of myths, speaker of truthiness to powerfulness, and defender of the Oxford comma.

Science and Philosophy

Medium’s center for scientifically-informed content.

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