THE SCIENCE OF GREENHOUSE GASES
Since the popularization of Atmospheric Thermal Variability known as "Global Warming" the term “Greenhouse Gases” has become more prominent than the science behind it.
What does the term "greenhouse" mean? "Greenhouse" refers to an enclosure where the atmosphere is maintained under favorable conditions. Greenhouses are generally dedicated to farm plants when outer environmental conditions are hostile (for example, for growing summer vegetables in inhospitable surroundings). The system of a greenhouse depends on blocking the free exchange of gases between the atmosphere inside the greenhouse and the outside environment, thereby delaying heat transference by convection (transference of energy through currents in a volume). Thus the greenhouse allows the temperature to be maintained at a tepid level to avoid stress or death to the vegetables from excessive outside cooling.
Do “Greenhouse” Gases exist? In the strictest sense of the word, no, they do not, because gases are fluids in continual motion, always filling the spaces towards which gases can be dispersed. Air masses in motion generate currents which permit the transference of energy when a large mass of gas moves from one spatial region to another. Remember that energy (for example, heat) will always flow from a high-density system to other low-density systems -which is the same as saying that the energy always flows from a higher-density state to a lower-density state. The transference of energy through currents in fluids is known as convection.
GREENHOUSE EFFECT IN OUR CARS
Is the warming of a car interior when parked in direct sunlight a greenhouse effect? Yes, the effect is precisely the same, because the exchange of gases between the car interior and the outer environment is obstructed by the glass and body shell. In other words, when we leave our cars in direct sunlight with windows and doors closed, we block the gas currents or the movement of fluid masses between the car interior and the outer environment, thus allowing only convection inside the car. As the interior atmosphere absorbs energy, it warms up only until it reaches a certain limit because gases cannot absorb heat ad infinitum and because a percentage of the heat is transferred from the internal environment to the bodywork of the car and from the bodywork to the external environment by means of conduction. After which, heat is again transferred to the air by convection and radiation.
INSIDE OUR CARS
Atmospheric heat passes through our car windshields by means of conduction, where it then hits molecules of metal, plastic and cloth. As the heat is absorbed by these materials their molecules and free electrons move more quickly and collide with each other emitting heat with a longer wavelength. The heat is then transferred by conduction from the bodywork to the interior environment of the car where the gases absorb the heat and move faster. The colder masses of gas absorb heat from the hotter masses of gas by convection. The heat hitting the gas molecules of the atmosphere inside the car is transformed into kinetic energy. This transformation of heat into kinetic energy and the ensuing molecular collisions generate heat with a longer wavelength and is transferred from the interior of the car to the bodywork by convection and slowly from there to the environment through conduction.
The heat in the car interior is uniformly distributed through the air trapped inside by convection. There is no heat transfer by convection to the external atmosphere because in tightly closing our cars we restrict the flow of air between the inside and outside environments. Under these conditions, the warming of the interior of our cars under direct sunlight does follow the greenhouse effect. However, there is no change in infrared wavelengths. The heat (from the Sun) which penetrates our cars is not the same as the heat generated by the movement and collisions of the gas molecules inside our cars. The Sun's infrared radiation wavelength is about 500 nanometers, while the Earth's infrared radiation wavelength is about 10 micrometers. The infrared radiation wavelength inside our cars is slightly less than 10 micrometers. Thus, the heat incoming from the Sun is not the same heat emitted by the atmosphere, and both the infrared radiation of the Sun and the infrared radiation of the atmosphere are not the same as the infrared radiation intercepted by the gases in the inner atmosphere of our cars.
As we reduce convection, heat transfer to the environment will depend mostly on conduction and radiation, which means that heat transfer is slower than if, otherwise, it would be through transfer by all possible mechanisms.
Imagine an activity for three people. Three workers complete a job in 30 minutes; if we lay one worker off leaving only two, the time it will take to do the same work will increase by 10 minutes; consequently, two workers will complete the same work in 40 minutes. If we lay off another worker, then the time it takes the one remaining worker would stretch by another 10 minutes, so one person alone would do the same work in 50 minutes. Imagine that, by sealing our cars, we are eliminating one of the workers (convection) controlling the diffusion of heat from the interior of the car toward the environment outside. The heat emitted by the car has a more elongated wavelength than the heat radiated by the Sun. Then the heat in the interior of the car flows more slowly than the heat emitted by the Sun. The heat in the atmosphere, water and soil flows slowly because the mass of their molecules limit its speed, while waves of heat emitted by the Sun are electromagnetic waves that displace at the speed of light. Solar heat passes quickly through the atmosphere; whereas heat released through the transformation of infrared radiation into kinetic and potential energy flows more slowly to outer space. This is the Greenhouse Effect; though the gases of the atmosphere are not “Greenhouse” gases, but THERMAL CONVEYORS.
Did you know that the Earth at night does not freeze over because the oceans, lakes and ponds transfer heat more slowly than the atmosphere and ground?
All transformation from one kind of energy into another kind of energy generates heat. All kinds of transformation from one kind of energy into another kind of energy are not 100% efficient (Second Law of Thermodynamics). But what happens to all of the heat generated by the transformation of infrared radiation into kinetic and chemical energy in the atmosphere? The heat is radiated to outer space; we think heat in outer space is transferred to the gravity field. Some people do not understand how heat can be deposited in the gravity field. You should know that heat is not a thing, but energy in movement. In this case, as we are talking about heat, we are talking about energy in motion carried by photons as gravitational energy that travels at the speed of light. Given that the energy density of the atmosphere is higher than the energy density of the gravity field, the photons are transferred to that lower density field. The interaction between photons and gravity is a probability function. (Accioly et al. /2000). Nasif Nahle, Biologist
WHAT HAPPENS IN THE ATMOSPHERE? Nasif Nahle, Biologist
Incoming infrared radiation from the Sun and from other stars -including supernovas- enters the atmosphere. Atmospheric gases absorb heat making the molecules gain momentum (heat transforms into kinetic energy) and impelling chemical reactions among them (heat transforms into chemical energy). Given that all interchanges and transformations of energy imply a deficit of heat, the heat generated by the motion of the molecules and the chemical reactions is transferred through convection to other regions of the atmosphere. A quantity of heat generated in the atmosphere is transferred by conduction and convection to the ground and oceans while at the same time a percentage of heat is radiated to outer space. Thus, heat is not accumulated or stored in the atmosphere. This idea is inconceivable because it implies a perpetual increase in warming. If it were so, then the Earth would have scorched to a crisp many billion of years ago.
Heat radiated by the atmosphere to outer space and transferred to other systems is not the same as incoming heat from the Sun. Water vapor in the atmosphere and the land and oceans absorb incoming shortwave-infrared radiation from the Sun and radiate longwave-infrared radiation released by the transformation of Potential Energy into Kinetic Energy. The heat produced by the movement of the molecules and the chemical reactions in the atmosphere is RADIATED from Earth to outer space. The soil, the oceans, the snow and the clouds all REFLECT a percentage of the cosmic heat back to outer space.
Greenhouse gases are not a barrier preventing the transference of heat to other settings. The "Greenhouse" gases are components of the terrestrial atmosphere which makes all life on Earth possible. If there was no oxygen in the atmosphere, life could still be possible anyway. Remember, oxygen was scarce in the terrestrial atmosphere for many millions of years before photosynthetic organisms came to flourish on Earth. If the terrestrial atmosphere did not have "greenhouse" gases, Earth would be a frozen planet where the existence of living beings would be impossible.
Atmospheric gases – all of them - absorb energy. However, it is Carbon Dioxide which has been singled out as the main cause of “Global Warming”. At its present concentration (378.9 ppmv or 0.0332%) in the atmosphere, CO2 is able to raise the tropospheric temperature by only 0.03° C; however, the tropospheric temperature anomaly has reached 0.42° C. This discrepancy reveals that the registered tropospheric temperature variability is not the result of CO2, but of a higher density of incoming energy from the Cosmos –Solar Radiation and Interstellar Cosmic Rays. (Science article here)
NASIF NAHLE, BIOLOGIST
We relate atmospheric gases to the warming of the Earth because some of them –water vapor, carbon dioxide, methane, nitrous oxide and some particles like dust and soot- acquire a molecular dynamics when they absorb heat, generating in turn heat through the transformation of potential energy into kinetic energy and through chemical reactions given between the various gas molecules and other compounds in the atmosphere. In particular, we should bear in mind the following formulas:
Daylight Events: Potential energy of atmospheric gases + heat from the Sun and other regions of the Universe --> Kinetic energy of atmospheric gases + heat released from movement of the molecules of atmospheric gases + heat released by collisions among molecules + cosmic heat absorbed by ground and water --> Earth warms somewhat, but is maintained fresh by the transference of heat from the ground and other solids to the oceans and atmosphere.
Nasif Nahle, Biologist
Night Events: Kinetic energy of the molecules of atmospheric gases --> potential energy from the decreasing exchange of energy + diminishing heat incoming from outer space + radiation of atmospheric heat to outer space + heat transfer from the atmosphere to water --> Earth cools somewhat, but is maintained warm by heat diffused from water to the ground and atmosphere.
Nasif Nahle, Biologist
Many other factors warm or cool the Earth, but I have summarized matters here to improve comprehension of the text. For example, I have not taken into consideration the heat released by other sources (for example volcanoes). I have also overlooked Interstellar Cosmic Particles, which evidently are warming the Earth and other planets in our Solar System (read here). Nasif Nahle, Biologist
In an e-briefing of the New York Academy of Sciences, reported by Christine Van Lenten, William Ruddiman informs us that climate changes 12000 years ago were caused by human harvesting activities.
Ruddiman seems to think that the agricultural activities of a handful of ancient communities were responsible for an unusual increment of methane in the terrestrial atmosphere.
Indeed, we need to generate about 295 million metric tons (295 billion Kg or 650 billion pounds) of rotting organic products to increase the concentration of atmospheric methane up to 0.3 %. The current harvest production (grain and hay) is 1.841 billion tons per year. This gross production generates 921 million metric tons of stubble, of which 230 million tons are left on the land or discharged as refuse and consequently putrefy in open environments. In 6000 BD, there was no agricultural machinery or domesticated draft animals, capable of pulling ploughs (ploughs did not even exist, and the only domesticated animals were dogs and perhaps cats). These early farmers -who walked the land barefoot and sowed seeds with sticks - would barely have been able to release 0.00007% of methane into the atmosphere from clearing land and from rotting vegetal garbage (mainly from lofts of rice and wheat because other cereals like maize, and leguminous plants like beans and soy beans, had not yet been domesticated) and from decaying wild animal wastes (manures and gasses).
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