B. Does Mars Support a Greenhouse Effect?
The IPCC Table relating to Mar indicates that the temperature above a black-body temperature was caused by the Greenhouse Effect. Again no calculation, analysis, proof, or discussion was presented to support the statement.
Mars has a reported average temperature of minus -60 degrees C and an atmosphere containing 95% carbon dioxide. Although the above Table indicates that Mars had an 80% CO2 concentration, most studies place it at 95%. NASA has it at 80% CO2. The difference is sizable suggesting that there was either a math error in the reporting or subsequent Mar’s investigations have improved the data.
The IPCC Table indicates that Mar’s black body temperature is minus -57°C. The average actual temperature on Mars is significantly different. Using the -60°C value reported by multiple sources, then it shows Mars to be colder (4°C) than it would be if it had no atmosphere. That does not make sense. According to Kirchhoff’s Radiation Law, the existence of an atmosphere should slow the cooling/heating process. Using the IPCC value of -47°C from the above Table above then it shows that Mars is about 10°C warmer than the black-body temperature. This would be consistent with what the expected should be, i.e. higher than the black body temperature.
Wikipedia reports an average high of minus -5.7°C and an average low of minus -78.5°C with an arithmetic average being minus -42.5. [ https://en.wikipedia.org/wiki/Climate_of_Mars%5D A measurement at one crater does not translate to the entire Mars surface. However, it does provide some support for the IPCC minus -47°C value.
Wikipedia reports that the Mars atmosphere is much thinner than on Earth, i.e. less than 1% (0.006atm) of Earth’s atmosphere. Because the IPCC contends the entire 523°C temperature effect on Venus was caused by the CO2 atmosphere, and Mars has a similar concentration of CO2. One of the reasons given why Mars is not warmer via the Greenhouse Effect is because the atmosphere is too thin. The Earth’s Stratosphere is similar to Mars, i.e. about 0.006 atm on Mars and .01atm at mid-height of the Stratosphere. Both have similar temperatures. The probability of an infrared photons colliding with CO2 molecules in the Stratosphere is determining by multiplying the density (pressure) and the mole ratio of CO2 in each atmosphere. This shows that the probability of infrared absorption on Mars is 140 times higher than in the Earth’s Stratosphere. Therefore, if the thin atmosphere on Mar’s is the justification why Mars is not warmer, then the arguments that the Stratosphere on Earth is where CO2 does its Greenhouse Effect work are inconsistent by over 100 times. The physical gas and radiation laws on Mars should be the same as they are on Earth.
NASA also supports the argument that a thin atmosphere allows the radiation to escape unimpeded in the Stratosphere. Actually NASA suggests that a thin atmosphere where absorption is unimpeded occurs at an elevation below the Stratosphere.
“Heat radiated upward continues to encounter greenhouse gas molecules; those molecules absorb the heat, their temperature rises, and the amount of heat they radiate increases. At an altitude of roughly 5-6 kilometers, the concentration of greenhouse gases in the overlying atmosphere is so small that heat can radiate freely to space.” Emphasis added https://earthobservatory.nasa.gov/features/EnergyBalance/page6.php
The Stratosphere starts at about 12 kilometers. At 5 to 6 kilometers, the pressure is about .5 atmospheres and the water vapor drops to about 1600 ppmv (mixing ratio of 1 g/kg). This concentration remains dominates over second place CO2.
Often common sense explains observations. Mars is cold because it is too far away from the sun, has a mass of one-tenth that of Earth and cannot hold on to any significant atmosphere, and has a wide elliptical orbit. It also has no ocean to modulate the temperature. The Greenhouse Effect plays no measurable role.