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Rebuttal of Miskolczi’s alternative greenhouse theory
Rob van Dorland1 and Piers M. Forster2
1 Royal Netherlands Meteorological Institute, De Bilt, The Netherlands
2 School of Earth and Environment, University of Leeds, Leeds, United Kingdom
Miskolczi (2010) theorizes that atmospheric CO2 increases cannot lead to an enhanced
greenhouse effect and therefore cannot be a cause of global warming. We show his
theory to be incorrect both in its application of radiation theory and from direct
atmospheric observations.
Introduction
Miskolczi (2007 and 2010) uses complex radiative transfer calculations on 228 measured
atmospheric profiles of temperature and greenhouse gases to theorize ‘physical rules’ for the
Earth’s energy balance. He deduces a ‘radiative exchange equilibrium law’, stating that on
average the downward thermal infrared flux at the Earth’s surface (Ed) and the absorbed
infrared radiation within the atmosphere (Aa) are equal. Miskolczi, shows that his law implies
that the Earth’s atmosphere should have a constant infrared optical thickness. Therefore,
when carbon dioxide concentrations increase, other greenhouse gases should decrease to
compensate. He then performs additional radiative calculations to suggest that observations
since 1950 show that this is happening.
We firstly indentify problems with Miskolczi’s theory and calculations and then show that in
fact observations do not support his theory. It should be emphasized that we do not criticize
radiative transfer models since they are based on fundamental well understood physics and
have been applied in many fields of science, e.g. astronomy. Similar calculations have been
routinely performed in atmospheric physics and climate studies using radiative models of
similar complexity and these agree very well with observations.
Problems with Miskolczi’s theory
Miskolczi (2010) proposes a ‘radiative exchange equilibrium law’, stating that on average the
downward thermal infrared flux at the Earth’s surface (Ed) and the absorbed infrared
radiation with the atmosphere (Aa) are equal. By claiming that this approximate equality is a
physical law Miskolczi is putting an additional unphysical constraint on atmospheric radiative
transfer. In reality this approximate equality is caused by the fact that the upward surface flux
is absorbed in the lower atmosphere and the downward infrared flux (Ed) also originates
from this same region. This is due to the fact that the mass of most greenhouse gases is
concentrated at lower levels and the temperature of these levels do not deviate much from
the surface temperature. In this sense, Miskolczi did not find anything new. In fact, Miskolski
overstates the equality of these two terms. Kiehl and Trenberth (1997) and Van Dorland
(1999) find differences of 25 Wm-2 (over 5%) if clouds are accounted; Van Dorland (1999)
additionally shows that clouds (globally averaged) increase both terms, Aa and Ed, almost
equally. Therefore, the difference between Aa and Ed in the aforementioned cloudy case
also applies to the clear sky case of Miskolczi.
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The theory of Miskolczi is at odds with analyses of observations, including his own.
As a next step using his quasi radiative equilibrium model, Miskolczi calculates the
relationship between outgoing longwave radiation (OLR) and the infrared flux originating from
the Earths surface (Su). The relationship is a function of infrared optical depth (τA) only. The
results are plotted in Miskolczi’s Figure 7. As can be seen from that plot that there are
significant deviations from Miskolczi’s best fit. Converted into OLR difference we may
calculate maximum differences of more than 40 Wm-2 (20%). Therefore, his optical depth
function is not a robust finding.
Miskolczi, 2010, Figure 7: The gray open circles are the 228 TIGR2 ascent data (profiles),
and the 61 black dots, not visibly resolved in this diagram because they are so nearly
coincident, are the NOAA annual averages. The black open circle is the average of the 228
ascent data and dashed line is the optical thickness in the global average temperature profile
(GAT).
From Miskolczi’s Figure 7 it can be concluded that the OLR is dependent on the infrared
surface flux (Su) and infrared optical depth (τA). This supports greenhouse theory. However,
Miskolczi concludes that the optical depth in his global average temperature profile, τA =
1.867, must be constant value by stating “That the three global average optical thicknesses
lie close to 1.87 is an indication that the global average atmosphere has a preference in
setting its infrared optical properties”. It's an average in his Figure, but no clear physical
reason is stated why should it be fixed and nothing in his observations suggests it should be.
The consequence of setting a constraint on optical depth is that if the carbon dioxide
concentration increases, other greenhouse gases must decrease. Miskolczi (2010) claims
that the amount of water vapour is declining in time supporting his theory. He used NOAA
2
NCEP/NCAR reanalysis (2008) results to suggest this (see Miskolczi’s Figure 11).
NCEP/NCAR reanalysis is known to have poor long-term trends. What Miskolczi analysis
actually shows is that water vapour fluctuations are dominantly responsible for the changes
in optical depth, which is a reasonable finding. More importantly, his Figure 11 is a good
illustration of the fact that the optical depth is not constant, and is therefore inconsistent with
his own theory.
A more robust analysis of water vapour changes by Mears et al. (2010) shows that total
column water vapour is increasing over the oceans in the period 1988-2009 at a rate of 0.27
+/- 0.08 mm/decade. This corresponds to about 1.2%/decade (IPCC, 2007). Although
observations of trends in relative humidity are uncertain, they suggest that it has remained
about the same overall, from the surface throughout the troposphere, and hence increased
temperatures will have resulted in increased water vapour. Over the 20th century, based on
changes in sea surface temperatures, it is estimated that atmospheric water vapour
increased by about 5% in the atmosphere over the oceans (IPCC, 2007).
Miskolczi, 2010, Figure 11: Summary of the perturbation study with the NOAA annual mean
time series data. Here the normalized variability is plotted for the CO2, H2O and temperature
perturbations. The reference value (61 year mean) of is 1.868754. The open circles indicate
the sum of the ∆ τ(c), ∆ τ(u), and ∆ τ(tA) curves [Eds: the computed changes in infrared
optical depth due to carbon dioxide, water vapour and temperature, respectively]. The thick
black ∆ τ curve is the unperturbed anomaly in the original . Obviously, the fluctuations of
global average ∆t are very largely explained immediately and directly by variations in water
vapor column amounts.
Finally, direct observations of OLR support an increasing greenhouse effect. For example,
Chen et al. (2007) analysed satellite observations of the clear sky infrared emitted radiation
by the Earth from between 1970 to 2006 and showed changes in the outgoing spectrum,
which agreed with those expected from known changes in the concentrations of greenhouse
3
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gases over this period of 36 years. Changing spectral signatures in CH4, CO2, and H2O were
observed, with the difference signal in the CO2 matching well between observations and
modelled spectra. Thus, the greenhouse forcing of the Earth has been directly observed to
increase in response to greenhouse gas concentration increases, counter to Miskolczi’s
theory.
Conclusion
The alternative greenhouse theory of Miskolczi (2007,2010) results in a constant infrared
optical depth with time, meaning that there can be no increasing greenhouse effect with time.
Miskolczi suggests that observations show this ratio to be fixed. However, both observations
and calculations with physically sound radiative transfer models show that Miskolczi’s theory
does not stand up to scrutiny. Moreover, there is ample observational evidence that the most
important greenhouse gases, water vapour and carbon dioxide have increased in the last
four decades, meaning that the total infrared optical depth is indeed increasing. Finally, direct
satellite observations of the outgoing infrared spectrum show that the greenhouse effect has
been enhanced over this period. Even the calculations of Miskolczi show a change of optical
depth with time. Therefore, neither observations nor radiative transfer theory can support
Miskolczi;s conclusions.
References
Chen, C., J. Harries, H. Brindley, M. Ringer, 2007; Spectral signatures of climate change in
the Earth’s infrared spectrum between 1970 and 2006
ERBE Monthly Scanner Data Product. NASA Langley Research Center, Langley DAAC User
and Data Services, 2004, userserv@eosdis.larc.nasa.gov
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to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change
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Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York,
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Mears, C., J. Wang, S. Ho, L. Zhang, and X. Zhou, 2010: Total column water vapor [in “State
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Journal of the Hungarian Meteorological Service, 2007, 111(1), 1–40.
NOAA NCEP/NCAR Reanalysis data time series, http://www.cdc.noaa.gov,2008
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