Hot on the heels of the Lewis and Curry paper, we have this new paper, which looks to be well researched, empirically based, and a potential blockbuster for dimming the alarmism that has been so prevalent over climate sensitivity. With a climate sensitivity of just 0.43°C, it takes the air out of the alarmism balloon.

The Hockey Schtick writes: A new paper published in the Open Journal of Atmospheric and Climate Change by renowned professor of physics and expert on spectroscopy Dr. Hermann Harde finds that climate sensitivity to a doubling of CO2 levels is only about [0.6C], about 7 times less than the IPCC claims, but in line with many other published low estimates of climate sensitivity.

The paper further establishes that climate sensitivity to tiny changes in solar activity is comparable to that of CO2 and by no means insignificant as the IPCC prefers to claim.

The following is a Google translation from the German EIKE site with an overview of the main findings of the paper, followed by a link to the full paper [in English].

Assessment of global warming due to CO2 and solar influence

Currently climate sensitivity (discussed for example here ) is claimed by the IPCC mid-value to be 3.0 C (AR4) as the most probable value, but others have determined much lower values ​​of 1.73C or 1C or even 0.43C. Prof. Hermann Harde, renowned physicist and Spektral analytiker has determined from his new paper the climate sensitivity is [0.6 C]

Editor’s note: The “climate sensitivity” said quantity was invented to carry the presumption in meaningful ways into account that the global mean temperature of the atmosphere could possibly be driven in a certain way by increase in carbon dioxide concentration in the air. To this end, forces defined (postulated) called. “Forcings”, whose influence, by means of certain physically based and mostly plausible assumptions, to accomplish this increase as migration out of balance. One of the factors is required for the climate sensitivity. It indicates how much K (° C) doubling the heating of the CO2 concentration rises.

Hermann Harde* , Experimental Physics and Materials Science , Helmut-Schmidt-University, Hamburg , Germany

Open Journal of Atmospheric and Climate Change, In Press

Abstract

We present an advanced two-layer climate model, especially appropriate to calculate the influence of an increasing CO2-concentration and a varying solar activity on global warming. The model describes the atmosphere and the ground as two layers acting simultaneously as absorbers and Planck radiators, and it includes additional heat transfer between these layers due to convection and evaporation. The model considers all relevant feedback processes caused by changes of water vapour, lapse-rate, surface albedo or convection and evaporation. In particular the influence of clouds with a thermally or solar induced feedback is investigated in some detail. 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).

Conclusion

The objective of this paper was to examine and to quantify the influence of GH-gases on our climate. Based on the HITRAN-2008 database [4] detailed spectroscopic calculations on the absorptivities of water vapour and the gases carbon dioxide, methane and ozone in the atmosphere are presented. The line-by-line calculations for solar radiation from 0.1–8 mm (sw radiation) as well as for the terrestrial radiation from 3–100 mm (lw radiation) show, that due to the strong overlap of the CO2 and CH4 spectra with water vapour lines the influence of these gases significantly declines with increasing water vapour pressure, and that with increasing CO2-concentration well noticeable saturation effects are observed limiting substantially the impact of CO2 on global warming.

The calculations were performed for three climate zones, the tropics, mid-latitudes and high-latitudes, based on actual data of the water vapour content, which is considerably varying with altitude above ground as well as with the climate zone and, therefore, with the temperature. The vertical variation in humidity and temperature as well as in the partial gas pressures and the total pressure is considered by computing individual absorption spectra for up to 228 atmospheric layers and then integrating from ground level up to 86 km altitude.

The varying path length of sun light in these layers, which depends on the angle of incidence to the atmosphere and therefore on the geographic latitude and longitude, is included by considering the Earth as a truncated icosahedron (Bucky ball) consisting of 32 surface elements with well defined angles to the incident radiation, and assigning each of these areas to one of the three climate zones.

Propagation of the long-wave radiation, in particular the up- and down-welling radiation, emitted by the atmosphere itself, as well as their variation with temperature are derived from radiation transfer calculations for each zone.To identify the influence of the absorbing gases on the climate and particularly the effect of an increasing CO2-concentration on global warming, we developed an advanced two-layer climate model, which describes the Earth’s surface and the atmosphere as two layers acting simultaneously as absorbers and Planck radiators. Also heat transfer by convection and evaporation between these layers is considered. At equilibrium each, the surface as well as the atmosphere, deliver as much power as they suck up from the sun and the neighbouring layer or climate zone.

The model includes sw and lw scattering processes at the atmosphere and at clouds, in particular considering multiple scattering between the surface and clouds. It also includes the common feedback processes like water vapour, lapse rate and albedo feedback, but additionally takes into account the influence of a temperature dependent sensible and latent heat flux as well as temperature induced and solar induced cloud cover feedback.

As direct reference for the incident and outgoing fluxes in the model we use the energy and radiation budget scheme of Tremberth et al. [20], which at a reference CO2 concentration of 380 ppm and a ground temperature of 16 °C can well be reproduced.

With the sw and lw absorptivities as the key parameters in such model then the surface temperature and the lower atmospheric temperature are calculated as a function of the CO2 concentration. From the temperature variations, found at doubled CO2 concentration, the CO2 climate sensitivity and air sensitivity are derived.

Particularly the individual feedback processes with their different influence on the climate sensitivity are extensively discussed. While the albedo- and to some degree the lapse rate feedback are adopted from literature, the water vapour feedback is derived from the sw and lw absorptivity calculations over the different climate zones. With an amplification at clear sky conditions of 1:5 and at mean cloud cover of 1:2 these values are smaller than assumed in other climate models [27, 28].Since it is found that with increasing CO2 concentration the air temperature is less rapidly increasing than the surface temperature, the convection at the boundary of both layers rises with the concentration. As a consequence more thermal energy is transferred from the surface to the atmosphere. Similarly, with increasing temperature also evaporation and precipitation are increasing with the ground temperature. Both these effects contribute to negative feedback and are additionally included in the simulations. A special situation is found for the influence of clouds on the radiation and energy budget. From measurements of the global cloud cover over a period of 27 years it is deduced that the global mean temperature is increasing with decreasing cloud cover [25]. However, it is not clear, if a lower cloud cover is the consequence of the increasing temperature, or if the cloud cover is influenced and at least to some degree controlled by some other mechanism, particularly solar activities. In the first case a strong amplifying temperature induced cloud feedback had to be considered, this for the climate sensitivity as well as for a respective solar sensitivity, whereas in the other case the temperature induced cloud effect would disappear for both sensitivities and only a solar induced cloud feedback had to be included due to the solar influence.

A deliberate approach which mechanism really controls the cloud cover with its dominant influence on the climate and solar sensitivity can be derived from model simulations, which additionally include the solar effect and compare this with the measured temperature increase over the last century. These simulations, considering both effects, show that the observed global warming of 0.74 °C [51] can only satisfactorily be explained, when a temperature feedback on the clouds is completely excluded or only has a minor influence. Otherwise the calculated warming would be significantly larger than observed, or the thermally induced cloud feedback would have been overestimated. With a combination of temperature and solar induced cloud feedback we deduce a CO2 climate sensitivity of CS = 0.6 °C and a solar sensitivity, related to 0.1 % change of the solar constant, of SS = 0.5 °C. An increase in the solar activity of only 0.1 % over 100 years then contributes to a warming of 0.54 °C, and the 100 ppm increase of CO2 over this period causes additional 0.2 °C in excellent agreement with the measured warming and cloud cover. From our investigations, which are based on actual spectroscopic data and which consider all relevant feedback processes as well as the solar influence, we can conclude, that a CO2 climate sensitivity larger 1 °C seems quite improbable, whereas a value of 0.5 – 0.7 °C – depending on the considered solar anomaly – fits well with all observations of a changing solar constant, the cloud cover and global temperature. A climate sensitivity in agreement with the IPCC specifications (1.5 – 4.5 °C) would only be possible, when any solar influence could completely be excluded, and only CO2 induced thermal cloud feedback would be assumed, then yielding a value of 1.7 °C.

It should be noticed that different to global circulation models, which try to predict local climate variations over some time period and, therefore, have to solve complex coupled nonlinear differential equations with countless parameters, for tracing the climate sensitivity this is of no significance. We calculate an equilibrium state and can average over larger local variations, for which a partitioning into three climate zones is quite sufficient. In addition, a simple energy balance model, focussing on the main physical processes, is much more transparent than any AOGCM and can help to better understand the complex interrelations characterizing our climate system.

Full text, open access: http://www.scipublish.com/journals/ACC/papers/download/3001-846.pdf