Those conversant with the AGW-debate will know that CO2 lags temperature. This phenomenon is observed in the Vostok ice-core data and shows an
800-year lag between temperature changes and corresponding CO2 changes. Advocates of the man-made warming hypothesis say that sceptics have
misinterpreted the lag and that it doesn’t disprove that CO2 is one of the planet’s primary drivers of temperature. Their argument as Skeptical
Science explains is that “as ocean temperatures rise, oceans release CO2 into the atmosphere. In turn, this release amplifies the warming trend,
leading to yet more CO2 being released”. So in other words, increasing CO2 levels become both the cause and effect of further warming. This
explanation has always sat uncomfortably with me and seems ad hoc – the ice-core data appears to show causation in largely only one-direction, that
is, CO2 consistently lags temperature. There is a lack of evidence, as far as I can see, in the ice-core data of CO2 being one of the primary drivers
of the planet’s temperature. If something consistently occurs after an event, most people would infer that as a ‘consequence’ not a ‘cause’.
So, anyway, I was browsing some graphs and I stumbled upon the graph below. The graph is based on the HADCRUT surface temperature data and the
unsmoothed CO2 measurements from Keeling Curve. It shows the lag throughout the 20th century. There’s a visible time-lag, with temperature
consistently preceding CO2 changes. I think the question that I would pose to advocates of the man-made warming hypothesis is: how can CO2 changes be
responsible for temperature changes that occurred before the CO2 changes? It surely violates ‘cause and effect’. It is tantamount to someone
arguing that cancer causes smoking. The cause and effect relationship is backwards. If CO2 was such a powerful driver of temperature, why does it not
cause temperature changes? Why instead are temperature changes causing CO2 changes? A likely explanation is that the temperatures of the oceans are
regulating the amount of CO2 in the atmosphere. The solubility of CO2 is temperature-dependent meaning that the amount in the atmosphere is governed
by ocean temperatures. As they cool, CO2 is absorbed into the oceans. As they warm, more CO2 is outgassed from the oceans. It’s clear from the graph
below that CO2 changes are a consequence of temperature, not a cause.
So, if CO2 is not causing temperature to change, as clearly evident in the graph above, why is that? At a concentration of 0.04% (about 1 molecule in
every 2,500 other molecules spread evenly throughout the atmosphere), perhaps its heating-power has been overestimated? The standard formula for
calculating CO2’s ‘radiative forcing’ is as follows: RF = ln(C/C0). It looks impressively scientific at first sight. But is it correct? And how
may we tell? The formula produces 3.7W/sq.m of radiative forcing for a doubling of atmospheric CO2 which would increase the temperature by about 1C.
The formula appears everywhere, from blogs such as Skeptical Science to scientific papers. When one investigates the origin of this formula you
discover that it’s based on radiative-transfer models (HITRAN and MODTRAN), which apparently according to Skeptical Science “use fundamental
physical equations and observations to translate this increased downward radiation into a radiative forcing”. I have attempted to find the
derivation for this formula myself but to date have been unsuccessful. Apart from sharing similarities with Arrhenius’ formula, I have seen no
empirical evidence demonstrating the formula’s authenticity. The HITRAN and MODTRAN computer-model codes are owned by the US air-force and the
derivation for the formula is contained on their master-discs.
The IPCC’s logarithmic formula’s essential conflict with the laws of physics can be seen most graphically from the fact that the equation implies
that the global warming from all the CO2 on the planet Venus should be just 38C, when the actual global warming on Venus is over 450C. So much for
spectral line-by-line computations.
See my Venus article here: chipstero7.blogspot.co.uk...
Advocates of the man-made warming hypothesis will occasionally point to ‘Harries 2001’ as empirical proof of CO2’s warming capabilities, but
when asked what the satellite-measured radiative forcing on CO2-wavebands is within the paper, they suddenly go very silent, because they don’t
know. The paper after all exists behind a pay-wall and the majority of IPCC-apologists haven’t read the paper. However there’s been a number of
experiments, as far back as 1954 by Hottel to determine CO2’s total absorptivity/emissivity (it’s potential to absorb and emit radiation), and the
results have been, well probably not too surprising to real scientists. As Prof. Nasif Nahle explains, “According to experiments conducted by H. C.
Hottel, B. Leckner, M. Lapp, C. B. Ludwig, A. F. Sarofim and their collaborators, and other scientists, the total absorptance potential of carbon
dioxide is ~0.003”. These experiments were conducted with CO2 in a saturated state. With some hairy mathematics the resultant temperature increase
with regard to the planet’s surface turns out to be: σ[(288^4) – (255^4)//(1/0.7) + (1/0.003) – 1]= 0.45W/sq.m (about 0.08C). CO2’s very low
emissivity may explain why global surface temperatures have been flat for 10 years, as acknowledged by Hansen.
Nasif Nahle: www.ilovemycarbondioxide.com...
In the article below Nasif Nahle criticizes the IPCC for treating atmospheric greenhouse gases like blackbodies with an emissivity of 1, which means
they absorb all radiation.
Perhaps CO2’s small effect has something to do also with the fact that it behaves logarithmically – which means increasing concentrations have
less and less effect. See graph below. The first 20ppmv of CO2 does the heavy-lifting, and after that the warming from CO2 is pretty much
inconsequential. Beyond 100ppmv it has little to no effect.
I am not suggesting that AGW is not real. Just that it has been overestimated.
I hope this has been somewhat informative. Some articles I have written:
Cold truth about CO2: chipstero7.blogspot.co.uk...
The validity of paleo-climate ice-core: chipstero7.blogspot.co.uk...
The Revelle Factor vs Henry’s law: chipstero7.blogspot.co.uk...
Atmospheric CO2 short residence time: chipstero7.blogspot.co.uk...
An inconveniently omitted fact: chipstero7.blogspot.co.uk...
Could clouds be responsible for late 20th century warming:
edit on 24-6-2013 by Nathan-D because: (no reason