CO2, water, and CH4 (methane) and some other minor gases are so-called “greenhouse gases” because they absorb infrared energy. However, be careful to avoid the common misunderstanding that the earth and its atmosphere behave like a garden greenhouse; that is not true. Greenhouses are closed systems except to incoming energy. Earth is an open system, open to receive energy, as well as gases and other matter from space and also open to transmit energy, gases and matter back into space. A greenhouse is a poor analogy for earth’s climate.
Greenhouse gases also re-emit almost instantly the energy they absorbed, emitting that energy at a slightly lower energy than which it was absorbed. Rarely is that emission mentioned in the news or by climate alarmists. Proponents of global warming want you to believe that energy is stored and builds up in the atmosphere in a sort of hothouse or pressure cooker, but that is not true.
In most locations, the concentration of water vapor (including clouds) in the atmosphere is far higher than CO2 and methane. Near the equator and bodies of water, swamps and tundra the concentration of water vapor in atmosphere will be near 100%. That is, no more water vapor can be added to the air at a given temperature and air pressure. Water vapor concentration in air is found in the range of 0% to 100%. Cold air holds very little water vapor. The air at the poles is often very dry. Warm air holds much water vapor.
The tropics and sub-tropics receive large amounts of solar irradiation during the day, but none at night. During the day, the surface of the ocean water is warmed by solar radiation and that warmth releases large amounts of CO2 and CH4 as well as water vapor into the atmosphere; this amount dwarfs all contributions of humans from all sources. At night, the cooler ocean surface absorbs large amounts of CO2. CO2 is very soluble in cold water.
The oceans and subsea floor hold far more methane (CH4) than all petroleum and fossil fuels ever discovered, and this methane is continuously degassed out of warm water and soil into the air. CH4 released into open air spontaneously converts (oxidizes) to CO2 and water at standard temperature and pressure. CH4 + 2 O2 -> CO2 + 2 H2O + a small amount of energy. Almost all CH4 originated as living cells. The cells died, entered the soil, rivers, lakes and ocean as runoff, metabolized and degraded by natural biological activity; this is the ultimate source of almost all fossil fuel on earth. That natural resource is continuously renewing and unlikely to be exhausted so long as there is life in the oceans.
Water vapor is the dominate greenhouse gas, absorbing by far both more direct solar energy and indirect solar energy re-emitted by the earth. More than 70% of the earth is covered with liquid water and about 40% of the earth and liquid water is receiving direct solar radiation every day. Additional liquid water is on land and in soil and plants. Solar radiation increases the molecular activity of liquid water molecules until they can no longer be held by the surface tension of the water. These active water molecules evaporate, i.e. release energetic water molecules, to become gaseous water vapor in the atmosphere. This release of energetic molecules cools the surface of the water, not warm the water, they just left. Your skin is cooled when your sweat evaporates.
Liquid water is far denser than air. Dense liquid water in the oceans is a huge reservoir of stored energy. The oceans contain greater than 1000 times more energy than the atmosphere; this means that earth’s atmosphere as a whole – regardless which gases make up the atmosphere – cannot warm the oceans in any significant amount. And this means the oceans are warming the atmosphere. The oceans are controlling the weather and climate on earth, not the atmosphere. The oceans are warmed by direct and indirect solar radiation as well as volcanic and tectonic forces resulting from gravity.
The specific gas molecules (nitrogen, oxygen, water vapor, as well as CO2, methane, and several other trace gases) that make up the atmosphere, each with their various concentrations, individually or in combination, are irrelevant to the long-term average temperature of the planet. In other words, an atmosphere of 100% CO2 could not significantly change the earth’s average temperature; instead, the ocean with its huge heat content would control the temperature of the 100% CO2 atmosphere. The atmosphere cannot warm significantly the earth over an extended time period, such as a year. But a warm ocean current, such as an El Nino, can change our climate and weather overnight.
However, water vapor and CO2 cause relatively minor temperature changes of the atmosphere at the surface (troposphere.) Water vapor and CO2 delay the release of energy from the earth into outer space, and this is most evident at night. Night time air temperatures at earth’s surface would be significantly cooler without water vapor and CO2. In a sense, greenhouse gases act as a nighttime insulator for the earth.
The effects of this are clearly seen at night. In warm, humid climates like New Orleans, the warmth of the air is retained late into the night, finally cooling by morning. Water vapor and CO2 do that. In dry desert or arctic areas, the warmth of the day very rapidly is re-radiated into outer space and nighttime temperatures plunge rapidly. The absence of water vapor and CO2 do that. CO2 has the same effect as water vapor/humidity except in far less amount than water vapor/humidity. CH4 is even less than CO2.
Nitrogen (70%), oxygen (20%), and water vapor (1%) are the primary gases in the atmosphere, but these gases are mostly transparent to direct solar radiation. Transparent means there are very limited or no energy bands available in these gaseous molecules to absorb energy at the wavelengths of the incoming solar radiation. A significantly large amount of solar energy is reflected by earth’s clouds, land and water surfaces back into outer space; this effect is known as albedo. The trace atmospheric gases in total comprise less than 1% of the atmosphere; this 1% includes the inert gases (mostly argon which makes up 0.96%). Trace gases carbon dioxide, methane and all other gases combined make up only 0.04% of air.
Most radiant energy of the sun is transmitted through the gases in the atmosphere to the surface, i.e. to water and land surface, where it is absorbed. Most solar radiation is in the higher energy infrared, visible and ultraviolent wavelengths. Visible light, UV, X-Ray, and gamma radiation are all higher energy (higher frequency/shorter wavelength) than IR. Water vapor absorbs at certain visible energy bands…so we see darkening clouds as water vapor concentration increases. Solar radiation is absorbed by the molecules at the surface of water and land is spread through conduction and convection and dissipated in the energy cascade in the molecules of the water or solid matter. Some energy is re-emitted from the surface (land and water) into the atmosphere at lower energy, longer wavelengths, lower frequency than which it was originally absorbed.
Solar radiation received by the earth is known as Total Solar Irradiance (TSI). TSI has a cycle involving multiple variables which I will not go into here except to point out that climate cycles on earth correlate well with the TSI cycle and also with ocean temperature cycles known as PCDO.
Temperature does not track CO2 very well (figure 11 below). Note temperature is flat, increasing, declining, and increasing while CO2 is increasing. Statistical correlation is weak.
Over longer time periods, the correlation between CO2 and temperature is very poor. The two trends are widely diverging as seen in the graphic below. If the global warming hypothesis were valid, these two trends would be parallel or converging.
For the remainder of this discussion, I will consider only energy in the infrared (IR) wavelengths. Molecules in water and land absorb IR at several discrete higher energy/shorter IR wavelengths that match discrete energy bands of the electrons of each molecule. If the incoming energy does not match an energy band of the molecule, or if that energy band is not available to absorb because the band is already occupied with energy, then the energy passes through the molecule without being absorbed. If the IR energy is absorbed, then in a fraction of a second, part of that energy is dissipated as kinetic energy (various motions such as stretching, bending, and vibrations internal to the molecule or collisions with other molecules) leaving slightly lower energy/slightly longer wavelength/slightly lower frequency IR energy. That lower energy is then re-emitted. Since part of the energy has already been dissipated internally by the molecule, the emission has a longer wavelength, lower frequency of IR than the IR that was originally absorbed. Energy is not stored in a molecule except in the macro sense of all molecules taken together, and then only temporarily while the energy is progressively dissipated. Energy moves from one molecule to the next and at each step the energy is reduced. By this process, IR energy is absorbed by a water vapor, or CO2 molecule, or CH4 molecule for only fraction of a second and then re-emitted at a longer wavelength (lower frequency, lower energy, cooler). This cascade continues progressively downward in the energy until eventually the remaining energy is dissipated as kinetic energy by collision with other molecules, or various internal molecular motions.
IR radiation is a sub-spectrum within the overall solar radiation spectrum. IR is 49.4% of solar energy reaching the outer atmosphere of earth. H2O, CO2, and CH4 absorb IR radiation ONLY at specific, discrete wavelengths (or quanta, or energy bands). Other wavelengths, which include most down-dwelling IR radiation directly from the sun, pass transparently through the molecules. Water vapor does absorb some incoming direct IR radiation. Some H2O, CO2, CH4 absorption wavelengths overlap (see graphic Figure 5-2), that is, these three molecules absorb IR at some of the same discrete wavelengths. This means that the gas which has the highest concentration in air absorbs and re-emits the most IR radiation. On average, water vapor including clouds is the highest concentration among the greenhouse gases, and thereby water vapor including clouds is the dominant greenhouse gas.
Most direct solar IR passes through air molecules to interact with molecules on the surface of water or land. Thus, infrared radiation is largely responsible for warming Earth’s surface, both land and water. In other words, the sun is not DIRECTLY warming the atmosphere, but INDIRECTLY warming the atmosphere. Most solar energy is absorbed in the molecules of the ocean and land which in turn warm the atmosphere. Most greenhouse warming is caused by reflected IR and IR emitted after dissipation from higher energy visible and UV energy. We don’t perceive visible light as heat; but when visible light interacts with matter, unless reflected, its energy is dissipated step by step in the downward energy cascade as described above until it becomes longer wavelength IR which then we perceive as heat. Re-radiation, conduction and convection from the surface of water and land warms the atmosphere.
IR energy only penetrates a few meters beneath the surface in liquid water in the oceans and lakes, while visible light transmits many meters beneath the surface of water, progressively loosing its colors from red to eventually higher energy blue and finally no visible light at increasing depth. The higher energy, shorter wavelength, higher frequency UV, x-ray and gamma energy mostly transmits through liquid water and finally interacts with molecules in solid matter in land or sea floor, or minimally with inorganic molecules dissolved in ocean water. Molecules on land and the seafloor surface are irradiated by these higher energy wavelengths, absorbing this energy, or conducting it further, and then these molecules progressively dissipate their energy as described above to progressively longer wavelengths and lower energy, eventually to IR wavelengths. The energy cascade continues on down the energy spectrum to satellite, wireless, radio, TV, MRI wavelengths and finally dissipated as kinetic motion of the molecule itself or collision.
The earth and the atmosphere also reflect and emit energy back into outer space, mostly in the visible and IR bands. IR emission from the atmosphere, water and land into outer space occurs day and night and is measured by satellite. Earth is an open system, continuously re-radiating its energy (which originally came from the sun) back into outer space, that is, radiating from higher energy earth to the much lower energy outer space beyond our atmosphere.
The fact that earth’s temperature is relatively stable over long periods of time, millions of years in multiple geological periods, implies that there is a balance between incoming energy and outgoing energy. I won’t go further into this energy balance topic here.
Over the very long time period of millions of years leading to the present, the earth has been in a slow cooling trend and has had a slowly declining atmospheric CO2 concentration as indicated in these graphics; this is probably contrary to what you have been told and taught.
On the other hand, and probably what you have been taught, in the geological short term, that is since the Little Ice Age and Industrial Revolution, earth warmed and total CO2 concentration increased. However most of that warming occurred before the 1950’s and that period was prior to the highest CO2 emissions by humans due to use of fossil fuels. In other words, the warming that followed the end of the Little Ice Age had very low CO2 concentration, thus that CO2 could not have caused the warming that occurred. The warming that occurred since the end of the Little Ice Age is within the statistical variation of the much longer-term cooling trend. In geological terms, since there is year-round ice at both poles, our present period is part of an interglacial period within an ice age.
As previously state here, there has been global warming during our lifetime, occurring before the 1950’s, but this warming is not unprecedented. And there has also been global cooling during our lifetime, also not unprecedented.
Returning to our “greenhouse gases,” the takeaway point is, again, the sun heats the earth, then the earth heats the atmosphere. The atmosphere is not heating the earth. According to the laws of thermodynamics, energy only flows only from higher energy earth to lower energy atmosphere. Earth (oceans and land) heat the air, not the reverse. Where can we measure this effect in the natural world? Detrended (i.e. seasons removed) sea surface temperatures versus air temperatures, we see in the graph below that increasing air temperature ALWAYS FOLLOWS increasing sea surface temperature. No matter how high the CO2 or methane concentrations are in the air, the ocean temperature will control the air temperature of the earth. In bulk, water vapor, CO2, and methane temporarily delay the dissipation of energy/heat via the process described in the above paragraphs.
According to the proposed hypothesis for human-caused global warming (AGW), the continuing accumulation of CO2 in the atmosphere causes or forces increased warming in the atmosphere. The hypothesis requires disregarding the important facts that warming has currently stopped and also that there has been cooling for some periods in our lifetimes and historically, when according to AGW there should have been an increasing rate of warming due to the increasing concentration of CO2. Also, again falsifying the AGW hypothesis, when warming periods have occurred, there is no difference in the rate of warming during those periods despite the fact that CO2 has increased.
Based on a single molecule, one CH4 molecule absorbs more energy and re-emits more energy than one CO2 molecule, and one CO2 molecule absorbs more energy and re-emits more energy than one H2O molecule. But, the concentration (or abundance) of water vapor in air is about 1%, while the concentration of CO2 in air is only about 0.04% (or 400 ppm) and the concentration CH4 in air is only about 0.0018% (or 1.8 ppm). There are far more water vapor molecules in the air to absorb the IR energy upgoing from the earth. Also, the IR radiation absorption wavelengths of water vapor overlap most of the IR radiation absorption wavelengths of CO2 and CH4. Since the concentration of water vapor is more than 10 times higher than that of CO2 and 100 times higher than CH4, the IR radiation emitted by the ocean, land and sun is more than 10 times more likely to be absorbed by water vapor molecules than by CO2 molecules and 100 times more likely to be absorbed by water vapor molecules than CH4 molecules. Then, when the water vapor, CO2 and CH4 molecules re-emit their energy upgoing or else collide, once again these emissions or collisions are far more likely to be interactions with a water vapor molecule.
With regard to CO2 and CH4, then net result is that exponentially less warming results from each incremental increase in CO2 or CH4 concentration. The natural logarithm function is the inverse of the exponential function. The graphic below illustrates the natural log curve of temperature versus CO2 concentration that results from progressively increasing the CO2 concentration. In climatology terms, climate and temperature sensitivity are progressively diminished as CO2 concentration increases. Each doubling of CO2 concentration results in incrementally less warming, following a logarithmic progression. The available quantum energy bands of CO2 and CH4 are already occupied with energy received from nearby molecules. Adding more absorbing molecules decreases the mean-free-path of the radiation between molecules. Progressively higher levels of CO2 (and methane) produce progressively less warming.
Furthermore, of the approximate 400 ppm (or 0.04%) total CO2 concentration in earth’s atmosphere, humans from all sources emit only about 3% of that total. About 97% of atmospheric CO2 is natural. About 98.5% of total CO2 is absorbed by nature.
CO2 concentration has been increasing since the end of the Little Ice Age, around the time of the Industrial Revolution, primarily because earth has been slowly warming since that time. The human contribution is minimal. But, since CO2 is not causing significant warming (or even reproducibly measurable warming), and since the earth is in fact becoming greener according to NASA satellite studies, then there is no good reason to reduce CO2, or to reduce use of fossil fuels. Also, since most CO2 is natural, there is no practical way for humans to significantly reduce atmospheric CO2 concentration. Carbon sequestration, carbon offsets, carbon taxes, carbon trading are environmentally useless, harmful, economically wasteful, fraud. On the contrary, there are benefits to higher CO2, such as increasing crop yields. And there are also benefits to warming.
Despite clear evidence that the atmosphere is not significantly warming the planet, and under the laws of physics could not significantly warm the planet, still some politicians and scientists try to alarm citizens to persuade them that increasing CO2 and CH4 concentration forces catastrophically dangerous, large increases in temperature trends by increasing absorption of IR by water vapor. The alarmists’ torturous and unvalidatable hypotheses and models treat water vapor as a feedback system rather than as the dominant greenhouse gas. But, if this hypothesis were true, and it is not, since CO2 has been increasing steadily since the end of the Little Ice Age (CO2 increased about 150% from a very low CO2 level), then we should be seeing rapidly rising global temperature due to this feedback forcing effect. However, the temperature trend has been only slightly increasing, and then only during some periods of time, and the warming trends are not exceptional or unprecedented in nature, and the overall temperature trend is diverging from the steadily rising CO2 trend. If CO2 were the cause of warming, then the CO2 and temperature trends would be parallel or converging during the same time periods; however, these correlations are not found in real world evidence unless the time periods are cherry-picked or the data has been manipulated. Even worse for the climate alarmists, there are multiple time periods, decades, where the temperature trend decreased while CO2 trend increased…for example the 1960s to late 1970s when most scientists and new outlets were proclaiming global cooling. CO2 cannot force both warming and cooling.
Cover of Time magazine, January 31, 1977.
As of December 2018, the global temperature measured by satellites (the most accurate and reproducible measurement available), is only 0.45 degrees F above the average temperature computed since 1978 when satellite measurement began, meanwhile CO2 has been steadily rising during this same period. In other words, nature has falsified the global warming hypothesis and climate models. Temperature has not been increasing in unison in correlation with increasing CO2. https://www.nsstc.uah.edu/climate/2018/december2018/GTR_201812Dec_1.pdf
Importantly, as shown in the graphic below, trends of increasing temperature precede trends of increasing CO2. Many peer-reviewed scientific papers confirm this observation. If CO2 were the cause or were forcing temperature increases, then that CO2 increase must precede the trend of increasing temperature; unfortunately for the AGW hypothesis and climate alarmists that evidence is not observed. Obviously, an effect cannot precede its cause. In other words, earth’s temperature is controlling CO2 concentration, not the other way around. (Al Gore’s science fiction movies show CO2 increases preceding or coincident with temperature increases leading up to a runaway ‘hockeystick’ warming.)
Most CO2 is emitted by the oceans and lands, naturally, by degassing caused by the slow warming trend since the Little Ice Age. Warmer water holds less CO2 than cold water. The relative partition ratio of a gas such as CO2 between water and air is controlled by Henry’s Law. Compared to the atmosphere, the oceans contain enormous energy (as already shown). Oceans contain about 50 times more CO2 than the atmosphere and 20 times more CO2 than the biosphere on land.
It would take 10,000 years for humans to change the temperature of the ocean by a mere 1 degree even if humans devoted all energy resources full time to that effort. The effects of the oceans on the earth’s climate are enormous, but the warming effect of human CO2 is trivially tiny.
The claim that the relatively tiny amount of CO2 contributed to the atmosphere by humans is controlling earth’s temperature is falsified according to the rules of science. We mere humans are not able to change the temperature of earth by adding or subtracting CO2, no matter the amount of CO2. Even if the air were 40% CO2, an amount that is 1000 times higher than today’s total CO2 and 10,000 times higher than the human contributed CO2, the atmosphere can not significantly warm the oceans. Oceans are a gigantic heat sink or reserve, moderating the earth’s temperature and controlling earth’s climate.
This is NOT to say that humans do not affect temperature and climate in other ways, such as building cities, roads, planting or cutting forests and fields, etc. This IS to say that AGW, the hypothesis of human-caused global warming by the contribution of a mere 0.004% of the total CO2 emissions, is scientifically wrong, statistically insignificant, so tiny it is unmeasurable in the real world; the hypothesis of human-caused global warming/climate change has been falsified by real world observations and experiments.
What is really going on?
António Guterres, the current Secretary General of the UN, is the former president of Socialist International, which “was formed in London on 28 September 1864 by socialist, communist and anarchist political groups and trade unions. Tensions between moderates and revolutionaries led to its dissolution in 1876 in Philadelphia. The Second International was formed in Paris on 14 July 1889 as an association of the socialist parties.” (Wikipedia) With member organizations in more that 100 nations, following the communist tradition of Karl Marx, Leon Trotsky and Vladimir Lenin, Socialist International views the chief source of oppression and exploitation in the world to be capitalism — private property — whose inevitable by-products are poverty, environmental degradation, war, famine, and most other ills that plague humanity. UN leaders have also announced the UN’s anti-capitalist intentions. http://www.socialistinternational.org/viewArticle.cfm?ArticleID=1902
Bottom line: the global warming / climate change agenda is a giant, global fraud. The where, why, who, and when proponents knew it was a fraud is a subject for another day and a court of law. The global warming/climate change agenda is a global, political scheme to re-distribute wealth, change national economic systems away from capitalism, reduce national and individual sovereignty and reduce citizen control of private property, and hand over funding and control to unelected supra-national alliances and organizations like the UN and the EU.