The fingerprints of the greenhouse effect

09/25/2019 14:06 - Posted by Tom van Leeuwen
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.

There seems to be a correlation between the concentration of CO2 and the earth's temperature in this period. But correlation does not imply causality . It can be pure coincidence that these two concepts are developing in a synchronized way. In a previous article we already saw that for other periods this correlation is nonexistent.

Infrared radiation fluxes

To check if there is a causality between these two concepts, we look for signs of phenomena inherent to the supposed heating process due to an enhanced greenhouse effect. These are like fingerprints that should be there if such an enhanced greenhouse exists. The measurement of these phenomena could lead us to a conclusion about the validity of the hypothesis.
According to the hypothesis, the increased concentration of greenhouse gases slows the cooling by infrared radiation of the earth's surface. This infrared radiation is absorbed by greenhouse gases and partially returned to Earth. This process would leave two fingerprints:
  • In the lower part of the atmosphere, near the earth's surface, we should observe an increased flux of infrared radiation to the surface that would be the energy that would effectively heat the Earth
  • In order for this energy to stay within the terrestrial system and can heat the Earth, in the highest parts of the atmosphere the tendency of the outgoing infrared radiation flux should remain constant or in any case, not increase more than the flux mentioned in the previous point.
What we are looking for is an alteration of the balance between conserved energy and energy lost to space. Without an alteration of this balance, the Earth can't be heated by the greenhouse effect.
This article explains in great detail how we came to identify these two fingerprints.

Checking the hypothesis

Combining the two fingerprints we can propose the following test to prove or disprove the hypothesis:

If there is an enhanced greenhouse effect, the flux of infrared radiation to the earth's surface should tend to gradually grow beyond the flux of infrared radiation into space.
If, on the contrary, there is no marked divergence in the trends of these two infrared radiation fluxes, the initial hypothesis would be refuted.

Fortunately, the satellite instruments NASA CERES provides us since 2000 with detailed data on these infrared radiation fluxes.

In the graph, we show the data of the CERES satellite measurement system. The light red line is the infrared radiation in the upper part of the atmosphere that will end in outer space while the dark red line is the infrared radiation directed to the earth's surface in the lower parts of the atmosphere.
We observe a clear coincidence of the two lines. There are periods of increase and decrease in radiation levels, especially during the period 2008-2012 that coincides with the consecutive phenomena of La Niña, El Niño and again La Niña and during the super-El Niño of 2016, but in no way can one speak of a gradual divergence between the trends of the two types of infrared radiation.


In the period from 2000 to 2018 we observed a clear increase in the concentration of CO2 in the Earth's atmosphere. At the same time, the average earth temperature rose by about 0.3 °C (satellite measurements from the University of Huntsville, Alabama (UAH)).
However, we do not observe any gradual divergence in the trends of infrared radiation flows in the upper part of the Earth's atmosphere compared to the lower part of the atmosphere, a divergence that would be a fingerprint of the increased greenhouse effect. The fingerprint is missing and therefore:

the hypothesis of climate change caused by human greenhouse gas emissions is refuted.

Natural causes

  • If the actions of man do not cause that temperature increase, then what is the cause?
    The start of industrial activity coincides almost perfectly with the end of the coldest period of the last 10 thousand years known as "The Little Ice Age". So the temperature rise since then is nothing more than the return to the 'normal' conditions of the Holocene before the Little Ice Age.

  • If CO2 is a greenhouse gas and its concentration is increasing, then why does this not cause the temperature rise we observe?
    Yes, that seems to be a contradiction, but it is not. CO2 only absorbs a small part of the electromagnetic spectrum, especially radiation in the wavelength band around 15 micrometers. Most of the infrared radiation is not affected by CO2.
    In addition, the CO2 greenhouse effect has a logarithmic trajectory. When the concentration of CO2 rises, there is less and less radiation in its bands of the electromagnetic spectrum available to be absorbed. Increasing the concentration of CO2 above a certain value no longer has a measurable effect on temperature. This phenomenon is known as "saturation". The CO2 greenhouse effect was already almost saturated with the CO2 levels present before the Industrial Revolution, so it has never played an important role in the entire period since then. More detailed information on the saturation of the greenhouse effect: Why did the warming stop?

Do you want to know more?

The first part of this article is a summary of this study. The original article offers much more details on how to reach our conclusion. Before you start reading the text it is useful to know some abbreviations:
  • DWLWIR - Downwelling Longwave Inward Radiation
  • EALOR - Effective Atmospheric Layer of Outward Radiation (the height at which radiation is more likely to be emitted into space than to return to Earth)
  • ToA - Top of Atmosphere
  • sfc - surface

Tom van Leeuwen, September 2019.


Please donate

Fighting the climate hysteria takes time! If you think I'm on the right track and you want to support my efforts I would be more than happy to receive a small donation that will help me to maintain this site.

Or donate some Bitcoin


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.

CO2 Band-Saturation Explained

Professor at the Geophysical Sciences department at the University of Chicago David Archer describes the band-saturation of the CO2 greenhouse effect. After that, everything goes wrong.

The first part of the lecture is very informative. Professor Archer explains in great detail how the CO2 greenhouse absorption works, it's logarithmic nature and the band saturation. He even shows on a working instance of the MODTRAN model how adding the first ppm of CO2 to the atmosphere has a huge impact on the atmosphere's energy balance. Adding more CO2, the effect fades away.

Hydroelectricity and greenhouse gasses

Hydropower is one of the cleanest energy sources available. The only downsides known so far are the impact on the landscape and the risk of a dam breaking due to earthquakes. Carefully choosing the locations and high construction standards are needed to solve these problems.

Besides electricity generation, dams also help to regulate the water flow in the rivers, making them better navigatable and useful for irrigation.

So, overall it seems to be quite positive, but recent research has "discovered" a new downside to hydroelectricity and it's a usual suspect: Greenhouse gasses.

The world needs more CO2

Interview with Professor William Happer of Princeton University. Mr. Happer is a renowned physicist, specialized in the field of atomic physics, adaptive optics and spectrometry. This interview from 2015 is part of the series "Conversations that Matter."

Some quotes from this interview:

The logarithmic nature of the CO2 greenhouse effect

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.

Water vapor

Water vapor is the single most important greenhouse gas. It makes up 80% to 90% of the total greenhouse effect of the Earth's atmosphere.

Climate models depend on water vapor as a positive feedback for supposed CO2 warming. In these models, CO2 causes a tiny warming that causes the relative atmospheric humidity to increase. That increase in water vapor produces the catastrophic warming they predict.
The problem is that in the real world, while atmospheric CO2-concentrations increased by almost 30% since the end of World War II, the relative atmospheric humidity has been stable at low altitudes and has even decreased at higher altitudes.