According to NASA, the solar radiation reaching Earths surface has a mean of about 161W/m^2 and such would only raise the temperature of an Earth paved all over with black asphalt (emissivity 0.93) to about 235K. Thats over 50 degrees colder than the estimated mean of about 287 or 288K. But wait ... theres less! The oceans are not covered with asphalt paving and their thin surface layers covering about 70% of Earth absorb less than 10% of the direct solar radiation. The other 90% gets absorbed further down in the colder ocean thermocline, and probably doesnt see the light of day again until it reaches the polar regions. So, for the thin ocean surfaces we should only use about 16W/m^2 and that, needless to say, gives absurdly cold temperatures when you bung it into Stefan-Boltzmann calculations. So we are not talking about just 50 degrees of warming by something (let alone only 33 degrees of warming) but maybe well over 100 degrees. Is water vapour really doing most of that? Water vapour in the lower troposphere varies between about 1% and 4% of the atmosphere. Is a mean of 2.5% raising the temperature 100 degrees? That would be 40 degrees of warming for each 1% in the atmosphere. So regions with 1% would be warmed 40 degrees and regions with 4% would be warmed 160 degrees, so wet rain forests would be 120 degrees hotter than dry deserts. Do you get the impression something must be wrong with this radiative forcing conjecture wearing the greenhouse label? What really does explain the warmer surface temperatures on all planets with significant atmospheres is the gravito-thermal effect postulated by the brilliant 19th century physicist Josef Loschmidt who was first to estimate realistically the size of air molecules. He also understood how gravity would affect those molecules while in flight between collisions. Now with 21st century physics, we have a better understanding of the Second Law of Thermodynamics, which applies to all energy and is in no way restricted to thermal energy. The Second Law describes a process wherein entropy increases towards a state of thermodynamic equilibrium wherein there are then no unbalanced energy potentials. You see, where the infant science of climatology goes wrong is in its general lack of understanding of thermodynamics. With limited knowledge, let alone understanding of thermodynamics, people like James Hansen made very serious mistakes in overlooking the fact that gravity sets up and maintains a density gradient (as the Second Law of Thermodynamics indicates will happen) and also a temperature gradient, as the Second Law of Thermodynamics also indicates, for each gradient is realised when the state of thermodynamic equilibrium is attained. Now, as explained for the first time in world literature in my book Why Its Not Carbon Dioxide After All this correct understanding of the Second Law of Thermodynamics leads to the inevitable conclusion that new thermal energy absorbed from solar radiation in a planets upper troposphere and above can and will diffuse in all accessible directions away from the source, including downwards, because the non-radiative dispersion is restoring the thermodynamic equilibrium. That is how, for example, the necessary thermal energy gets into the surface of Venus in order to raise its temperature by about 5 degrees over the course of its 4-month-long sunlit hours. Radiating molecules reduce the gradient by up to about a third on Earth, though only about 5% on Uranus by my calculations anyway. So, yes, it is the Suns energy which causes a planets surface to warm on the sunlit side, compensating for equivalent cooling in the dark hemisphere, but much of it enters the surface by convection (which in physics includes diffusion) and this is what is missing in those energy diagrams that show back radiation in lieu. To understand how even one-way radiation obeys the Second Law I refer you to the physics explained in my paper Radiated Energy and the Second Law of Thermodynamics published on several websites in March 2012. When you do understand this 21st century breakthrough regarding our knowledge of radiation, then you will realise that back radiation can only slow that portion of surface cooling which is itself by radiation. Back radiation cannot slow the majority of surface cooling which is by non-radiative processes, and these processes can actually accelerate to compensate for slower radiative cooling. In any event, it is the supporting temperature due to the gravito-thermal effect which ultimately determines at what temperature the cooling stops in the early pre-dawn hours, regardless of how fast the cooling has been earlier in the afternoon and night. So radiation to the surface is not the primary determinant of planetary surface temperatures, as is readily confirmed by a study of any planet with a significant atmosphere.
Posted on: Sat, 13 Sep 2014 21:46:10 +0000
Trending Topics
Recently Viewed Topics
© 2015