The logarithmic nature of the CO2 greenhouse effect

10/13/2019 09:00 - Posted by Tom van Leeuwen
For many people, a logarithmic relationship can be a fairly abstract concept. It is hard to imagine the implication that it has on the strength of the greenhouse effect that corresponds to the amount of CO2 that humanity emits into the atmosphere. Here we present a visualization to explain in a simple way what we are talking about.

CO2 is a greenhouse gas. The presence of CO2 in the atmosphere traps a part of the infrared radiation that the Earth's surface emits into space. The total greenhouse effect of the Earth's atmosphere is about 30 °C, without this effect, the temperature would be -15 °C instead of +15 °C, the actual current average temperature.
Water vapor is the most important greenhouse gas. CO2 provides 3 °C of heating, that is, 10% of the total effect.

When the concentration of CO2 increases, its greenhouse effect also increases, but not in a linear fashion, but logarithmically. For each increase in concentration, the effect on temperature is less and less.

In the main graphic of this article, generated using the radiation detection system of the United States Air Force (MODTRAN), the blue line represents the greenhouse effect of CO2. On the horizontal axis, we place the CO2 concentration and on the vertical axis the amount of energy the Earth receives per square meter of surface every second. The red lines mark the values of the beginning of the Industrial Revolution, the green lines the values for the year 2006 and the black lines the values that correspond to the doubled concentration we had at the beginning of the Industrial Revolution.
We observe that the CO2 greenhouse effect dramatically increases when the levels are low, while the increase in the effect is much lower with the current CO2 concentrations.

Given that the greenhouse effect of CO2 is only 10% of the total effect, it is clear that increasing the already existing concentration of CO2 in the atmosphere no longer has any measurable effect on the earth's temperature. This graphic is also from the US Army.

This phenomenon is known as the saturation of the CO2 greenhouse effect.

An approach to better understand the logarithmic progression of the effect:

We see that a tiny concentration of only 20 parts per million (ppm) is already sufficient to activate more than a third of the CO2 greenhouse effect. Increasing the concentration with 20 ppm to 40 ppm, the effect already produces 1.5 °C of heating, that's half of the total.
140 parts of CO2 per million is the minimum concentration necessary to sustain plant life. At this level, the greenhouse effect is completed by 67%. At the end of the last glacial period, 16 thousand years ago, the CO2 concentration was 180 ppm and its greenhouse effect was already 72% saturated.
At the beginning of the Industrial Revolution (1850), the saturation of the CO2 greenhouse effect reached 80%, 2.4 °C of the possible 3 °C. This means that CO2 emissions by humans never had any measurable effect on global temperature. For example: moving from the current 420 ppm CO2 to 440 ppm would cause heating of 0.02 °C.

With this knowledge it is clear why IPCC climate models do not work.
The models exaggerate the CO2 greenhouse forcing. They are programmed like this. From there, all positive feedback effects, such as the increase in the greenhouse effect of water vapor, fail.
The result is that the models forecast too much warming for the future.

If we could only get these images and this message to the responsible politicians, they would easily see that there is no rational reason to try to limit CO2 emissions.

Article based on this article from , the most visited climate website. I have corrected the heating °C of the third graph with the values calculated from the first graph. The heating of the first section is less than the 1.7 ° C value shown in the original graph. The other values have been changed accordingly.

Tom van Leeuwen, September 2019.


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The fingerprints of the greenhouse effect

The hypothesis of "man-made climate change" tells us that the increase in the concentration of CO2 enhances the greenhouse effect of the atmosphere and has global warming as a final result.

Since the beginning of the industrialized era around 1850, man emits relatively large amounts of CO2 into the atmosphere through the use of fossil fuels. The consequence of these emissions is that during that period, the concentration of CO2 in the atmosphere increased sharply from about 300 parts per million to more than 400 ppm, an increase of almost 40%. The average temperature increased in the same period more or less 1.5 °C with a small variation depending on the data source used.

Why did the warming stop?

The political reports of the IPCC are based on the hypothesis that CO2 is the most important control knob of the Earth's temperature. The problem is that this hypothesis does not correspond at all with the empirical data available to science. Forecasts are made using models that are not capable of 'predicting' the past.

Temperature versus CO2 – the big picture

When discussing “Climate Change” it’s good to have an understanding of how the Earth’s climate has changed in the past. That will give us a reference to decide whether the current changes are normal or not.

Global temperatures have varied a lot over the last 500 million years. Depending on the timescale used, the current temperature is either cold or hot, so when you want to know the “normal temperature” you’ll have to indicate what timescale you’re using.

Dutch Warming

In the Netherlands, the day-to-day whether depends heavily on the direction the wind is coming from. Being a small country, the wind direction is quite homogeneous for the whole country, specially on higher altitudes where the bulk of heat convection is taking place.

Due to its geographical position, midway between the icy-cold Arctic to the north, the dry and hot Sahara to the south, the Eurasian land-mass to the east and the Atlantic Ocean to the west, every wind direction comes with unique weather characteristics.

North - cold,
East - dry,
South - warm,
West - wet whether.

Satellite temperature observations

This month of January 2023, the average satellite temperature published, by Dr. Christy and Dr. Spencer (University Alabama Huntsfield) had a negative deviation, compared with the average monthly measures between 1991 and 2000.

Of course, this value does not mean much, it's definition is full of arbitrary begin and endpoints, but anyway it doesn't sound like a lot of warming has taken place over the past 30 years, and even less "catastrophic warming" we're reading about in the Mainstream Media, newspapers and TV stations.

CO2 saturation

This graph is all you need to understand that CO2 is not the Earth's Climate Control Knob.

On the horizontal axis, we see the Infra-red (IR) spectrum wavelengths, that is like "IR colors" were this kind of radiation visible to the human eye.
The vertical axis shows to energy flux, that is the energy emitted by the Earth, as seen from outer space.

The graph itself shows how the Earth's atmosphere filters the IR radiation emitted by the Earth's surface and the role of the various greenhouse gases in that filtering process. The green line is the filter of the Earth's atmosphere without any greenhouse gases.

Video - Who are the real climate deniers?

The climate has shown many fluctuations during the Holocene. The difference between the highest and lowest average temperature of the past 10 thousand years is about 3 °C.

Climate alarmists, led by the IPCC, are trying to deny this, and understandably so. This variation means that without human influence there was climate change as well.

This undermines their hypotheses and often their jobs depend on it.

Climate change seen from a historical perspective.

Satellite Earth temperature February 2022

The satellite temperature departure measurement for February 2022 is exactly 0° C.

This means that Earth temperature during February 2022 was exactly the same as the average from 1991 to 2020.

Satellites are the best way to have insight into the short-term temperature variations. They measure the whole surface, independent of weather station distribution, Heat Islands, measurement failures, surface condition (land or water).

There is a step-wise increase in temperature, triggered by two very strong El Niño events (1998 and 2016.) The energy that welled up from the deep oceans established a new level in these two ocasions, where the warming paused. This is a natural phenomenon and has nothing to do with CO2, or human activity.

Where is the Climate Emergency? It just does not exist.

Wake up and spread this information to your government!

Tom van Leeuwen, March 1st, 2022.