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].
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]
Advanced Two-Layer Climate Model for the Assessment of Global Warming by CO2
Hermann Harde* , Experimental Physics and Materials Science , Helmut-Schmidt-University, Hamburg , Germany
Open Journal of Atmospheric and Climate Change, In Press
Based on the HITRAN-2008 database  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.
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.
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.
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.
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.
budget scheme of Tremberth et al. , which at a reference CO2 concentration of 380 ppm and a ground
temperature of 16 °C can well be reproduced.
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 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 . 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.
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  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.
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.