By Dr. John Happs
Venus is named after the ancient Roman Goddess of love and beauty, also called Aphrodite by the Ancient Greeks. Presumably, the “love and beauty” term came from the fact that Venus is the brightest of all the planets in the night sky.
The Italian Galileo Galilei (1564-1642) was the first astronomer to observe Venus through a telescope and he observed that the planet had phases like our Moon. This observation supported the revolutionary (and politically dangerous) idea that Venus and other planets orbited the Sun.
Venus is similar in structure and size (slightly smaller) when compared to the Earth. It has the longest rotation period (243 days) of any planet in our solar system with little difference between day and night temperatures.
We often hear climate alarmist’s claim that, should we continue emitting carbon dioxide into the atmosphere (where carbon dioxide makes up a mere 0.04%), we could end up with an atmosphere like Venus (comprising 96.5% carbon dioxide, 3.5% nitrogen and traces of other gases such as sulfur dioxide). They argue that this would lead to runaway greenhouse heating on Earth.
The Earth is around 150 million km from the sun whilst Venus is much closer to the sun at about 108 million km but (against intuition) its proximity to the sun doesn’t explain the high temperature on Venus.
Venus is the brightest planet in the night sky because it reflects most of the solar radiation it receives from the sun. Albedo is a measure of the reflectivity of an object such that 100% reflectivity would give an object an albedo of 1 whilst an object that absorbs 100% of the radiation it receives has an albedo of 0.
Measurements from CERES spacecraft (Clouds and the Earth’s Radiant Energy System) give an average of the Earth’s albedo around 0.30. If our planet were covered in forest, it would have an albedo of around 0.14 compared to an albedo of 0.84 if it was covered in ice.
The upper atmosphere of Venus receives nearly twice as much solar radiation as the Earth but Venus has an albedo of 0.75 in that 75% of the radiation it receives from the sun is reflected back into space. Venus has high-level dense clouds containing sulphuric acid droplets. These clouds are up to 40km thick with bases around 30km altitude and relatively little solar radiation penetrates this cloud mass.
The question must be asked – if so little solar radiation penetrates the Venusian atmosphere, why is the average temperature on Venus around 460°C? (The melting point of lead is 327.5°C.)
One important clue that explains the high surface temperature and low upper atmosphere temperature of Venus is the dramatic change in atmospheric pressure. The ground atmospheric pressure on Venus is 92 times greater than that on Earth. This was determined in 1970 when the Russian spacecraft Venera 7 landed on the surface of Venus. It collected data for 23 minutes and was then melted and crushed by the tremendous heat and pressure.
In 1972, after 117 days, Venera 8 landed on the Venusian surface and transmitted data for 63 minutes before it too was melted and crushed.
The transmitted data were vital since they showed that the high temperature at the surface of Venus has little, if anything, to do with the so-called “greenhouse effect.”
The temperature-altitude profile for Venus is clear:
A comparison of the temperature and pressure profiles of Venus and Earth shows that at 50 km altitude the Venusian atmospheric pressure corresponds to the normal pressure on Earth with both temperatures approximately 37°C. This equates with temperatures that are not uncommon in our tropics.
In fact the high surface temperature on Venus is essentially a result of its atmospheric pressure (92 atmospheres) and not its composition. If the carbon dioxide (molecular weight 44) in the Venusian atmosphere were replaced by nitrogen (molecular weight 14) its surface temperature would be only slightly lower.
As Dr. Harry Dale Huffman has said:
“Listen to the physicists that tell you there is no greenhouse effect; they know without having to go to the Venus data — and I am one of them. The continuing incompetence on this vital point among so many scientists, for more than a century, is amazing, and tragic.”
There are many peer-reviewed, published papers that reject the so-called Greenhouse hypothesis. These can be located at:
The atmospheric lapse rate refers to the change in temperature with a change in altitude and the concept of lapse rate can be related to the atmospheres on other planets.
As mentioned previously, Maxwell pointed out that the atmospheric temperature gradient and warming are due to pressure and not radiative forcing. He related temperature at a given height to the pressure at that altitude in his 1872 book Theory of Heat.
Since Maxwell’s earlier work, other scientists have confirmed that the so-called “greenhouse effect” is actually a result of atmospheric mass/pressure/gravity, rather than radiative forcing from carbon dioxide.
Dr. Hans Jelbring writes:
“It is remarkable that the hypothesis claiming a quantitatively important anthropomorphic global warming (AGW) has survived for more than 100 years.”
Dr. Ned Nikolov and Dr. Karl Zeller in their 2017 paper: “New Insights on the Physical Nature of the Atmospheric Greenhouse Effect Deduced from an Empirical Planetary Temperature Model” write:
“The atmospheric ‘greenhouse effect’ currently viewed as a radiative phenomenon is in fact an adiabatic (pressure-induced) thermal enhancement analogous to compression heating and independent of atmospheric composition.
Compression heating would have been experienced by most people who have hand-pumped a bicycle tyre.
“The atmospheric greenhouse effect, an idea that many authors trace back to the traditional works of Fourier (1824), Tyndall (1861), and Arrhenius (1896), and which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. “
And: “There are no common physical laws between the warming phenomenon in glass houses and the fictitious atmospheric greenhouse effects,”
Other papers that reject the greenhouse hypothesis include: Davis et al. (2018) who say:
“Recent research has shown, however, that the concentration of CO2 in the atmosphere has been decoupled from global temperature for the last 425 million years.”
Hertzberg et al. (2017) examined the concept of “greenhouse gases” and various definitions of the phenomenon known as the Atmospheric Radiative Greenhouse Effect, concluding:
“The six most quoted descriptions are as follows: (a) radiation trapped between the Earth’s surface and its atmosphere; (b) the insulating blanket of the atmosphere that keeps the Earth warm; (c) back radiation from the atmosphere to the Earth’s surface; (d) Infra Red absorbing gases that hinder radiative cooling and keep the surface warmer than it would otherwise be – known as ‘otherwise radiation’; (e) differences between actual surface temperatures of the Earth (as also observed on Venus) and those based on calculations; (f) any gas that absorbs infrared radiation emitted from the Earth’s surface towards free space. It is shown that none of the above descriptions can withstand the rigours of scientific scrutiny when the fundamental laws of physics and thermodynamics are applied to them.”
Many other peer-reviewed, published papers refute the greenhouse hypothesis including Berberan-Santos et al. (1996)
Robinson and Catling (2013)
Kramm et al. (2017)
Lightfoot and Mamer (2017)
Davis et al. (2018): https://www.mdpi.com/2225-1154/6/1/3/htm
Velasco et al. (2020)
Problems of the greenhouse theory have also been discussed by Casey at: http://greenhouse.geologist-1011.net/
VOLCANISM ON VENUS – AN ADDITIONAL HEAT SOURCE
Investigations by scientists at the University of Maryland and the Institute of Geophysics in Zurich, Switzerland have used radar scanning to identify over 30 active volcanoes on Venus. Dr. Laurent Montési reported: “This study significantly changesthe view of Venus from a mostly inactive planet to one whose interior is still churning and can feed many active volcanoes.”
Venus, with more than 1,000 volcanic structures, has more volcanoes than any other planet in our solar system with more than 150 of these measuring over 100 km across. A number of these structures are “flattened pancake” dome volcanoes, covering hundreds of kilometres, formed by lava erupting under the very high pressure of the Venusian atmosphere.
Although global surface temperature is essentially determined by the Earth’s atmospheric pressure and water vapour, there is ample evidence to show that the sun and clouds are important drivers of our climate and weather. There are numerous other factors that have an impact on our climate and weather with atmospheric carbon dioxide being one of the least significant.
There is no empirical evidence to show that atmospheric carbon dioxide has ever driven global temperature and many climate alarmists with vested interests know this. Some continue to promote catastrophic carbon dioxide-driven global warming because it is financially and/or politically beneficial for them to do so.
Whenever scientists and other vested interest groups say that our future depends on addressing (imaginary) catastrophic global warming by stopping carbon dioxide emissions, they most likely mean that their income and/or ideology depends on it.
Dr. John Happs M.Sc.1st Class; D.Phil. John has an academic background in the geosciences with special interests in climate, and paleoclimate. He has been a science educator at several universities in Australia and overseas and was President of the Western Australian Skeptics for 25 years.