85 Papers Find Extremely Low CO2 Climate Sensitivity
(a) Quantified Low Climate Sensitivity to Doubled CO2
Smirnov, 2018 (2X CO2 = 0.4ºC) (2X AnthroCO2 = 0.02ºC)
From this, it follows for the change of the global temperature as a result at doubling of the concentration of atmospheric CO2 molecules [is] ∆T = (0.4 ± 0.1) K, where the error accounts for the accuracy of used values, whereas the result depends on processes included in the above scheme. Indeed, we assume the atmospheric and Earth’s albedo, as well as another interaction of solar radiation with the atmosphere and Earth, to be unvaried in the course of the change of the concentration of CO2 molecules, and also the content of atmospheric water is conserved. Because anthropogenic fluxes of carbon dioxide in the atmosphere resulted from combustion of fossil fuels is about 5% [Kaufman, 2007], the contribution of the human activity to ECS (the temperature change as a result of doubling of the atmospheric carbon dioxide amount) is ∆T = 0.02 K, i.e. injections of carbon dioxide in the atmosphere as a result of combustion of fossil fuels is not important for the greenhouse effect.
Smirnov, 2017 (2X CO2 = 0.4°C )
It is shown that infrared emission of the atmosphere is determined mostly by atmospheric water. One can separate the flux of outgoing infrared radiation of the atmosphere from that towards the Earth. The fluxes due to rotation-vibration transitions of atmospheric CO2 molecules are evaluated. Doubling of the concentration of CO2 molecules in the atmosphere that is expected over 130 years leads to an increase of the average Earth temperature by (0.4±0.2) K mostly due to the flux towards the Earth if other atmospheric parameters are not varied.
[W]e take into account that CO2 molecules give a small contribution to the heat Earth balance and, therefore, one can use the altitude distribution of the temperature for the standard atmosphere model , and a variation of the CO2 concentration does not influence this distribution. … [I]njection of CO2 molecules into the atmosphere leads to a decrease of the outgoing radiation flux that causes a decrease of the average Earth temperature. But this decrease is below 0.1K that is the accuracy of determination of this value. Thus, the presence of carbon dioxide in the atmosphere decreases the outgoing atmospheric radiative flux that leads to a decrease of the Earth temperature by approximately (1.8 ± 0.1) K. The change of the average temperature at the double of the concentration of atmospheric CO2 molecules is determined by the transition at 667cm−1 only and is lower than 0.1K.
In particular, doubling of the concentration of CO2 molecules compared to the contemporary content increases the global Earth temperature by ΔT = 0.4 ± 0.2K. … From this we have that the average temperature variation ΔT = 0.8 ◦C from 1880 up to now according to NASA data may be attained by the variation of the water concentration by 200ppm or Δu/u ≈ 0.07, Δu = 0.2. Note that according to formula (2) the variation of an accumulated concentration of CO2 molecules from 1959 (from 316ppm up to 402ppm) leads to the temperature variation ΔT = 0.15°C. One can see that the absorption of a water molecule in infrared spectrum is stronger than that of the CO2 molecule because of their structures, and the injection of water molecules in the atmosphere influences its heat balance more strongly than the injection of CO2 molecules.
Florides and Christodoulides, 2009 (2X CO2 = ~0.02°C)
A very recent development on the greenhouse phenomenon is a validated adiabatic model, based on laws of physics, forecasting a maximum temperature-increase of 0.01–0.03 °C for a value doubling the present concentration of atmospheric CO2. Moreover, data from palaeoclimatology show that the CO2-content in the atmosphere is at a minimum in this geological aeon. Finally it is stressed that the understanding of the functioning of Earth’s complex climate system (especially for water, solar radiation and so forth) is still poor and, hence, scientific knowledge is not at a level to give definite and precise answers for the causes of global warming.
Newell and Dopplick, 1979 (2X CO2 = ~0.25°C )
Estimates of the atmospheric temperature changes due to a doubling of CO2 concentration have be with a standard radiative flux model. They yield temperature changes of >0.25 K. It appears that the much larger changes predicted by other models arise from additional water vapor evaporated into the atmosphere and not from the CO2 itself. … It is important to stress…that CO2 is not the main constituent involved in infrared transfer. Water vapor plays the major role and ozone is also of importance. With the infrared region divided into 22 spectral intervals, the infrared and solar fluxes have been computed at levels from the surface up to 5 mb using a procedure originally developed by Rodgers (1967) and modified by Dopplick (1972). The procedure has previously been applied to the computation of heating rates for increased CO2 concentrations (Newell and Dopplick, 1970; Newell et al., 1972). Table 1 gives the results of computations using standard climatological data for January. Twenty of the spectral intervals are dominated by water vapor and the other two contain CO2 (~15 µm) and O3 (~9.6 µm), although overlap with water vapor is also included. Calculations were performed for CO2 concentrations of 330 and 600 ppmv, taking care to include the changed CO2 concentrations also in the near-infrared solar absorption (cf. Newell et al., 1972). Both sets of computations were also repeated with cloud absent. The infrared flux dominated by CO2, as is well known, is only about 10% of that controlled by water vapor. The decrease in infrared flux from the surface to the atmosphere due to the increase in CO2 ranges from 1.0 – 1.6 W m-2. The increased CO2 yields additional absorption of solar infrared radiation and therefore a decrease of solar energy available at the surface which ranges up to ~0.3 W m-2. The net change at the surface is an increase of 0.8 – 1.5 W m-2 with the smallest values at low latitudes. … The fact that water vapor dominates CO2 in the radiation budget has been known and discussed for many years (see, e.g., Kondratiev and Niilisk, 1960; Möller, 1963; Zdunkowski et al., 1975) but it seems important to reemphasize when so much attention is being paid to CO2.
The conclusion is that at low latitudes the influence of doubling CO2 on surface temperatures is less than 0.25 K
Idso, 1998 (2X CO2 = ~0.4°C)
Over the course of the past 2 decades, I have analyzed a number of natural phenomena that reveal how Earth’s near-surface air temperature responds to surface radiative perturbations. These studies all suggest that a 300 to 600 ppm doubling of the atmosphere’s CO2 concentration could raise the planet’s mean surface air temperature by only about 0.4°C. Even this modicum of warming may never be realized, however, for it could be negated by a number of planetary cooling forces that are intensified by warmer temperatures and by the strengthening of biological processes that are enhanced by the same rise in atmospheric CO2 concentration that drives the warming.
Chylek et al., 2007 (2X CO2 = 0.39°C)
Consequently, both increasing atmospheric concentration of greenhouse gases and decreasing loading of atmospheric aerosols are major contributors to the top-of atmosphere radiative forcing. We find that the climate sensitivity is reduced by at least a factor of 2 when direct and indirect effects of decreasing aerosols are included, compared to the case where the radiative forcing is ascribed only to increases in atmospheric concentrations of carbon dioxide. We find the empirical climate sensitivity to be between 0.29 and 0.48 K/Wm-2 when aerosol direct and indirect radiative forcing is included.
Gates et al., 1981 (2X CO2 = 0.3°C)
Preliminary analysis of experiments on the climatic effects of increased CO2 with an atmospheric general circulation model and a climatological ocean
Preliminary results from numerical experiments designed to show the seasonal and geographical distribution of the climatic changes resulting from increased atmospheric CO2 concentration are presented. These simulations were made for both doubled and quadrupled CO2 levels with an improved version of the two-level OSU atmospheric GCM. In these experiments and in a control run with normal CO2, the solar radiation incident at the top of the model atmosphere and the sea-surface temperature and sea ice were given prescribed seasonal climatological variations. In January the globally averaged tropospheric temperature is increased with respect to the control mean by 0.30°C (0.48°C) for doubled (quadrupled) CO2, which may be compared with an interannual January temperature variability of 0.15°C in the control (as measured by the root-mean-square of January monthly averages in a 3-year control integration)
Gray, 2009 (2X CO2 = ~0.4°C)
CO2 increases without positive water vapor feedback could only have been responsible for about 0.1 – 0.2 °C of the 0.6-0.7°C global mean surface temperature warming that has been observed since the early 20th century. Assuming a doubling of CO2 by the late 21st century (assuming no positive water vapor feedback), we should likely expect to see no more than about 0.3-0.5°C global surface warming and certainly not the 2-5°C warming that has been projected by the GCMs [global circulation models].
Harde, 2014 (2X CO2 = 0.6°C)
The short- and long-wave absorption of the most important greenhouse gases water vapour, carbon dioxide, methane and ozone are derived from line-by-line calculations based on the HITRAN08-databasis and are integrated in the model. Simulations including an increased solar activity over the last century give a CO2 initiated warming of 0.2°C and a solar influence of 0.54°C over this period, corresponding to a CO2 climate sensitivity of 0.6 °C (doubling of CO2) and a solar sensitivity of 0.5°C (0.1 % increase of the solar constant).
Ollila, 2012 (2X CO2 = 0.51 °C)
Scientists are still debating the reasons for “global warming”. The author questions the validity of the calculations for the models published by the Intergovernmental Panel on Climate Change (IPCC) and especially the future scenarios. Through spectral calculations, the author finds that water vapour accounts for approximately 87% of the greenhouse (GH) effect and only 10% of CO2. A doubling of the present level of CO2 would increase the global temperature by only 0.51 °C without water feedback.
Zdunkowski et al., 1975 (2X CO2 = 0.5°C)
It is found that doubling the carbon dioxide concentration increases the temperature near the ground by approximately one-half of one degree [0.5°C] if clouds are absent. A sevenfold [700%] increase of the present normal carbon dioxide concentration increases the temperature near the ground by approximately one degree. Temperature profiles resulting from presently observed carbon dioxide concentration and convective cloudiness of 50% or less are compared with those resulting from doubled carbon dioxide concentrations and the same amounts of cloud cover. Again, it is found that a doubling [100% increase] of carbon dioxide increases the temperature in the lower boundary layer by about one-half of one degree.
Cederlöf, 2014 (2X CO2 = 0.35°C)
By using this climate model, it is possible to estimate the hemispheres temperature response to increased radiative forcing from greenhouse gases. When assuming that the seasonal energy exchange between the hemispheres is neglectable and a doubling of the carbon dioxide level would cause 3.7 W/m2 forcing, a climate sensitivity figure can be calculated. This climate sensitivity has in this case been calculated to about 0.5°C for NH and about 0.2°C for the SH if IPCC’s assumptions of efficacy is used.
Idso, 1980 (2X CO2 = ≤ 0.26°C )
The mean global increase in thermal radiation received at the surface of the earth as a consequence of a doubling of the atmospheric carbon dioxide content is calculated to be 2.28 watts per square meter. Multiplying this forcing function by the atmosphere’s surface air temperature response function, which has recently been determined by three independent experimental analyses to have a mean global value of 0.113 K per watt per square meter, yields a value of ≤ 0.26 K for the resultant change in the mean global surface air temperature. This result is about one order of magnitude less than those obtained from most theoretical numerical models, but it is virtually identical to the result of a fourth experimental approach to the problem described by Newell and Dopplick. There thus appears to be a major discrepancy between current theory and experiment relative to the effects of carbon dioxide on climate. Until this discrepancy is resolved, we should not be too quick to limit our options in the selection of future energy alternatives.
Schuurmans, 1983 (2XCO2 = ~0.3°C )
For detection purposes we need to know the so-called transient response of climate to a given increase of the atmospheric CO2 concentration (observed or predicted). Transient response patterns, however, are generally much less well known than equilibrium responses. The problems encountered in specifying the transient CO2-induced climate signal are discussed in detail by Michael et al. in his book. From his review we may conclude that there is some general agreement amongst different modellers that the transient response of global mean temperature to increased CO2 concentration of the atmosphere at present amounts to less than 0.5 K (estimates of [temperature response] now varying between 0.2 and 0.4 K).
Kissin, 2015 (2XCO2 = ~0.6°C)
[A] doubling the CO2 concentration in the Earth’s atmosphere would lead to an increase of the surface temperature by about +0.5 to 0.7 °C, hardly an effect calling for immediate drastic changes in the planet’s energy policies. An increase in the absolute air humidity caused by doubling the CO2 concentration and the resulting decrease of the outgoing IR flux would produce a relatively small additional effect due to a strong overlap of IR spectral bands of CO2 and H2O, the two compounds primarily responsible for the greenhouse properties of the atmosphere.
Holmes, 2018 (2XCO2 = -0.03°C)
Calculate for a doubling of CO2 from the pre-industrial level of 0.03% [300 ppm]: [formula found in text] Calculated temperature after doubling of CO2 to 0.06% [600 ppm] ≈ 288.11 K. Climate sensitivity to CO2 is ≈ 288.14 – 288.11 ≈ – 0.03 K.
The change would in fact be extremely small and difficult to estimate exactly, but would be of the order -0.03°C. That is, a hundred times smaller than the ‘likely’ climate sensitivity of 3°C cited in the IPCC’s reports, and also probably of the opposite sign [cooling]. Even that small number would likely be a maximum change, since if fossil fuels are burned to create the emitted CO2, then atmospheric O2 will also be consumed, reducing that gas in the atmosphere – and offsetting any temperature change generated by the extra CO2. This climate sensitivity is already so low that it would be impossible to detect or measure in the real atmosphere, even before any allowance is made for the consumption of atmospheric O2.
Weare and Snell, 1974 (2X CO2 = 0.7°C )
Introduction: There has been in recent years a growing concern over possible inadvertent climate alteration by man’s activity (SMI, 1971; Matthews et al., 1971). As a result, there has been considerable effort devoted to developing predictive global climatic models (Budyko, 1969, 1972; Sellers, 1969, 1973), or to otherwise assessing the climatic effect of atmospheric pollutants (see, e.g., Manabe, 1971; Lamb, 1970; Rasool and Schneider, 1971; Bryson, 1972; Mitchell, 1970). This effort has been useful in providing tentative predictions and has certainly stimulated more interest and even controversy. However, the climatic models have relied heavily on simplified empirical parameterizations and, in general, none of the assessments have been very inclusive of many of the earth-atmosphere dynamic feedback mechanisms. For instance, one of the most important factors potentially affecting the radiation balance of the earth-atmosphere system is clouds because of their high reflectivity in the visible spectrum and absorption-emission in the infrared.
In Fig. 6 we present the results of altering atmospheric aerosol from the assumed present day-day value of about 0.1 optical depth units. … A doubling produces a 1K decrease in mean annual global surface temperature, whereas a fourfold increase produces somewhat more than a 3K decrease. … As may be seen in Fig. 7, a doubling of CO2 increase the mean annual global surface temperature according to our dynamical model by about 0.7K, but a sixfold increase only increases the temperature 1.7K. The nonlinearity is due to saturation of the 15 µm band.
Lindzen and Choi, 2011 (2X CO2 = 0.7°C)
As a result, the climate sensitivity for a doubling of CO2 is estimated to be 0.7K (with the confidence interval 0.5K – 1.3K at 99% levels). This observational result shows that model sensitivities indicated by the IPCC AR4 are likely greater than the possibilities estimated from the observations.
Kimoto, 2015 [full] (2X CO2= ~0.16°C)
The central dogma is critically evaluated in the anthropogenic global warming (AGW) theory of the IPCC, claiming the Planck response is 1.2K when CO2 is doubled. The first basis of it is one dimensional model studies with the fixed lapse rate assumption of 6.5K/km. It is failed from the lack of the parameter sensitivity analysis of the lapse rate for CO2 doubling. The second basis is the Planck response calculation by Cess in 1976 having a mathematical error. Therefore, the AGW theory is collapsed along with the canonical climate sensitivity of 3K utilizing the radiative forcing of 3.7W/m2 for CO2 doubling. The surface climate sensitivity is 0.14 – 0.17 K in this study with the surface radiative forcing of 1.1 W/m2.
Ollila, 2014 (2X CO2 = ~ 0.6°C)
The Potency of Carbon Dioxide as a Greenhouse Gas
According to this study the commonly applied radiative forcing (RF) value of 3.7 Wm-2 for CO2 concentration of 560 ppm includes water feedback. The same value without water feedback is 2.16 Wm-2 which is 41.6 % smaller. Spectral analyses show that the contribution of CO2 in the greenhouse (GH) phenomenon is about 11 % and water’s strength in the present climate in comparison to CO2 is 15.2. The author has analyzed the value of the climate sensitivity (CS) and the climate sensitivity parameter (l)using three different calculation bases. These methods include energy balance calculations, infrared radiation absorption in the atmosphere, and the changes in outgoing longwave radiation at the top of the atmosphere. According to the analyzed results, the equilibrium CS (ECS) is at maximum 0.6 °C and the best estimate of l is 0.268 K/(Wm-2 ) without any feedback mechanisms.
Harde, 2016 (2X CO2 = 0.7°C)
Including solar and cloud effects as well as all relevant feedback processes our simulations give an equilibrium climate sensitivity of CS = 0.7 °C (temperature increase at doubled CO2) and a solar sensitivity of SS = 0.17 °C (at 0.1 % increase of the total solar irradiance). Then CO2 contributes 40 % and the Sun 60 % to global warming over the last century.
Bates, 2016 (2X CO2 = ~1°C)
Estimates of 2xCO2 equilibrium climate sensitivity (EqCS) derive from running global climate models (GCMs) to equilibrium. Estimates of effective climate sensitivity (EfCS) are the corresponding quantities obtained using transient GCM output or observations. The EfCS approach uses an accompanying energy balance model (EBM), the zero-dimensional model (ZDM) being standard. GCM values of EqCS and EfCS vary widely [IPCC range: (1.5, 4.5)°C] and have failed to converge over the past 35 years. Recently, attempts have been made to refine the EfCS approach by using two-zone (tropical/extratropical) EBMs. When applied using satellite radiation data, these give low and tightly-constrained EfCS values, in the neighbourhood of 1°C. … The central conclusion of this study is that to disregard the low values of effective climate sensitivity (≈1°C) given by observations on the grounds that they do not agree with the larger values of equilibrium, or effective, climate sensitivity given by GCMs, while the GCMs themselves do not properly represent the observed value of the tropical radiative response coefficient, is a standpoint that needs to be reconsidered.
Evans, 2016 (2X CO2 = <0.5°C)
The conventional basic climate model applies “basic physics” to climate, estimating sensitivity to CO2. However, it has two serious architectural errors. It only allows feedbacks in response to surface warming, so it omits the driver-specific feedbacks. It treats extra-absorbed sunlight, which heats the surface and increases outgoing long-wave radiation (OLR), the same as extra CO2, which reduces OLR from carbon dioxide in the upper atmosphere but does not increase the total OLR. The rerouting feedback is proposed. An increasing CO2 concentration warms the upper troposphere, heating the water vapor emissions layer and some cloud tops, which emit more OLR and descend to lower and warmer altitudes. This feedback resolves the nonobservation of the “hotspot.” An alternative model is developed, whose architecture fixes the errors. By summing the (surface) warmings due to climate drivers, rather than their forcings, it allows driver-specific forcings and allows a separate CO2 response (the conventional model applies the same response, the solar response, to all forcings). It also applies a radiation balance, estimating OLR from properties of the emission layers. Fitting the climate data to the alternative model, we find that the equilibrium climate sensitivity is most likely less than 0.5°C, increasing CO2 most likely caused less than 20% of the global warming from the 1970s, and the CO2 response is less than one-third as strong as the solar response. The conventional model overestimates the potency of CO2 because it applies the strong solar response instead of the weak CO2response to the CO2 forcing.
Gervais, 2016 [full] (2X CO2 = <0.6°C)
Conclusion: Dangerous anthropogenic warming is questioned (i) upon recognition of the large amplitude of the natural 60–year cyclic component and (ii) upon revision downwards of the transient climate response consistent with latest tendencies shown in Fig. 1, here found to be at most 0.6 °C once the natural component has been removed, consistent with latest infrared studies (Harde, 2014). Anthropogenic warming well below the potentially dangerous range were reported in older and recent studies (Idso, 1998; Miskolczi, 2007; Paltridge et al., 2009; Gerlich and Tscheuschner, 2009; Lindzen and Choi, 2009, 2011; Spencer and Braswell, 2010; Clark, 2010; Kramm and Dlugi, 2011; Lewis and Curry, 2014; Skeie et al., 2014; Lewis, 2015; Volokin and ReLlez, 2015). On inspection of a risk of anthropogenic warming thus toned down, a change of paradigm which highlights a benefit for mankind related to the increase of plant feeding and crops yields by enhanced CO2 photosynthesis is suggested.
Soon, Connolly, and Connolly, 2015 [full] (2X [400 ppm] CO2 = 0.44°C)
Nonetheless, let us ignore the negative relationship with greenhouse gas (GHG) radiative forcing, and assume the carbon dioxide (CO2) relationship is valid. If atmospheric carbon dioxide concentrations have risen by ~110 ppmv since 1881 (i.e., 290→400 ppmv), this would imply that carbon dioxide (CO2) is responsible for a warming of at most 0.0011 × 110 = 0.12°C over the 1881-2014 period, where 0.0011 is the slope of the line in Figure 29(a). We can use this relationship to calculate the so-called “climate sensitivity” to carbon dioxide, i.e., the temperature response to a doubling of atmospheric carbon dioxide. According to this model, if atmospheric carbon dioxide concentrations were to increase by ~400 ppmv, this would contribute to at most 0.0011 × 400 = 0.44°C warming. That is, the climate sensitivity to atmospheric carbon dioxide is at most 0.44°C.
Reinhart, 2017 (2X [400 ppm] CO2 = 0.24°C)
Our results permit to conclude that CO2 is a very weak greenhouse gas and cannot be accepted as the main driver of climate change. … The assumption of a constant temperature and black body radiation definitely violates reality and even the principles of thermodynamics. … [W]e conclude that the temperature increases predicted by the IPCC AR5 lack robust scientific justification. … A doubling [to 800 ppm] of the present level of CO2 [400 ppm] results in [temperature change] < 0.24 K. … [T]he scientific community must look for causes of climate change that can be solidly based on physics and chemistry. … The observed temperature increase since pre-industrial times is close to an order of magnitude higher than that attributable to CO2.
Balling Jr, 1994 (2XCO2 = <1.0°C)
Close examination of the global temperature record, together with other factors, does not support the global warming models’ predictions – the thermal response to a doubling of CO2 is likely to be ‘remarkably small’.
An additional problem of linking the observed changes in surface temperature to the build-up of greenhouse gases involves the timing of the warming. The problem here is simple. The amount of warming from 1893 to 1992 shown in Figure 1 is well-established at 0.45°C. However, the amount of warming in the first half of the record (from 1893 to 1942) is 0.32°C; this result clearly shows that nearly three-quarters of the linear warming of this century had occurred before the time of the most rapid build-up of greenhouse gases.
As we have seen, the surface air temperature records show a linear increase of 0.45°C pver the past 100 years. However, urban heat islands may cause a 0.05°C reduction, overgrazing and desertification may lower the trend by the same amount as the urban heat island effect, and stratospheric aerosol variations may lower the trend by 0.15°C. And if we include the statistical association between sunspot cycle length and global temperature, the trend is almost eliminated. Even without considering the possible role of solar output, at least half of the warming of the past century can be explained by non-greenhouse phenomena, and most of that warming occurred in the first part of the record.
[T]he temperature record of the past century suggests that a doubling of carbon dioxide will produce a global temperature response at the lowest end of the model predictions – probably not more than 1.0°C.
Bellamy, 2007 (2XCO2= <1.0°C)
This paper demonstrates that the widely prophesied doubling of atmospheric carbon dioxide levels from natural, pre-industrial values will enhance the so-called ‘greenhouse effect’ but will amount to less than 1°C of global warming. It also points out that such a scenario is unlikely to arise given our limited reserves of fossil fuels—certainly not before the end of this century.
Abbot and Marohasy, 2017 (2XCO2= <0.6°C)
The largest deviation between the ANN [artificial neural network] projections and measured temperatures for six geographically distinct regions was approximately 0.2 °C, and from this an Equilibrium Climate Sensitivity (ECS) of approximately 0.6 °C [for a doubling of CO2 from 280 ppm to 560 ppm plus feedbacks] was estimated. This is considerably less than estimates from the General Circulation Models (GCMs) used by the Intergovernmental Panel on Climate Change (IPCC), and similar to estimates from spectroscopic methods.
The proxy measurements suggest New Zealand’s climate has fluctuated within a band of approximately 2°C since at least 900 AD, as shown in Figure 2. The warming of nearly 1°C since 1940 falls within this band. The discrepancy between the orange and blue lines in recent decades as shown in Figure 3, suggests that the anthropogenic contribution to this warming could be in the order of approximately 0.2°C. [80% of the warming since 1940 may be due natural factors].
Scafetta et al., 2017 (2XCO2= <1.0°C)
A millennial climatic oscillation would suggest that a significant percentage of the warming observed since 1850 could simply be a recovery from the Little Ice Age of the 14th – 18th centuries and that throughout the 20th century the climate naturally returned to a warm phase as it happened during the Roman and the Medieval warm periods. … We critically analyze the year 2015-2016, which has been famed as the hottest year on record. We show that this anomaly is simply due to a strong El-Niño event that has induced a sudden increase of the global surface temperature by 0.6 °C. This event is unrelated to anthropogenic emissions. … Herein, the authors have studied the post 2000 standstill global temperature records. It has been shown that once the ENSO signature is removed from the data, the serious divergence between the observations and the CMIP5 GCM projections becomes evident. … Since 2000 there has been a systematic tendency to find lower climate sensitivity values. The most recent studies suggest a transient climate response (TCR) of about 1.0 °C, an ECS less than 2.0 °C and an effective climate sensitivity (EfCS) in the neighborhood of 1.0 °C. …Thus, all evidences suggest that the IPCC GCMs at least increase twofold or even triple the real anthropogenic warming. The GHG theory might even require a deep re-examination.
Gray, 2018 (2XCO2 = 0.5°C)
[T]he globe’s annual surface solar absorption of 171 Wm-2 is balanced by about half going to evaporation (85 Wm-2) and the other half (86 Wm-2) going to surface to atmosphere upward IR (59 Wm-2) flux and surface to air upward flux by sensible heat transfer (27 Wm-2). Assuming that the imposed extra CO2 doubling IR blockage of 3.7 Wm-2 is taken up and balanced by the earth’s surface as the solar absorption is taken up and balanced, we should expect a direct warming of only ~ 0.5°C for a doubling of the CO2. The 1°C expected warming that is commonly accepted incorrectly assumes that all the absorbed IR goes to balancing outward radiation (through E = σT4- e.g., the Stefan-Boltzmann law) with no energy going to evaporation. … This analysis shows that the influence of doubling atmospheric CO2 by itself (without invoking any assumed water vapor positive feedback) leads to only small amounts of global warming which are much less than predicted by GCMs.
(b) Non-Quantified ‘Practically No Effect’, ‘Close To Zero’ CO2 Climate Sensitivity
Conventional theory of global warming states that heating of atmosphere occurs as a result of accumulation of CO2 and CH4 in atmosphere. The writers show that rising concentration of CO2should result in the cooling of climate. The methane accumulation has no essential effect on the Earth’s climate. Even significant releases of the anthropogenic carbon dioxide into the atmosphere do not change average parameters of the Earth’s heat regime and the atmospheric greenhouse effect. Moreover, CO2 concentration increase in the atmosphere results in rising agricultural productivity and improves the conditions for reforestation. Thus, accumulation of small additional amounts of carbon dioxide and methane in the atmosphere as a result of anthropogenic activities has practically no effect on the Earth’s climate.
[T]he measured increase in carbon dioxide in the atmosphere, according to the most recent computations, would not be enough to have any measurable climatic effect. Rasool and Schneider (1971) conclude that an increase in the carbon dioxide content of eight times the present level would produce an increase in surface temperature of less than 2°C, and that if the concentration were to increase from the present level of 320 parts per million to about 400 by the year 2000, the predicted increase in surface global temperature would be about 0.1°C.
There are accumulating evidences that the greenhouse effect in the Earth’s atmosphere is not a ‘free’ parameter and anthropogenic global warming (AGW) estimates based on the classic greenhouse theory and CO2 doubling experiments (usually conducted by general circulation models) are totally wrong. Based on large number of observed atmospheric thermal and humidity structures and global scale simulations of the true greenhouse gas absorption properties of the atmosphere it is shown that the global average clear sky greenhouse effect is constant. The observed true infrared optical thickness of the clear atmosphere is 1.87 and this value proved to be very stable in the last 61 years. With the help of the observed relationships among the radiative flux components and the association of those relationships with known fundamental physical laws new structural equations of the global radiation field were established. The theoretically predicted IR optical thickness is fully consistent with, and supporting the observed value of 1.87.