Peter Huber in his article ('Faith-Based Models', FORBES, Oct. 27, p. 105) continues his skeptical diatribe by writing:
"Some then try to deal with the fact that more cloud cover will reduce the amount of inbound sunlight that reaches the surface and also boost the amount of heat radiated back intio space from above the clouds and so on and so forth".
But as already noted (previous instalment) how cloud cover acts depends on the TYPE of cloud! As Prof. Gale Christianson ('Greenouse') has noted:
"wispy high flying cirrus are semi-transparent to incoming sunlight but block infrared radiation emitted by the Earth thus CONTRIBUTING to the Greenhouse Effect”
Thus, there is no real problem here other than what Huber has created. Reinforcing this the authors of the paper ('Can Earth’s Albedo and Surface Temperature Increase Together’ in EOS, Vol. 87, No. 4, Jan. 24, 2006, p. 37) have emphasized that:
"whereas low clouds have decreased during the most recent years, high clouds have increased to a larger extent leading to both an increase in cloud amount AND an increased trapping of infrared radiation"
Thus, high altitude cloud cover abets infrared radiation trapping and contributes to the global greenhouse.
Huber then disingenously refers to having to parse "millions of lines of terribly complex computer code" -but this isn't necessary to ascertain the effects of the cloud cover. However, satellite data from a range of meteorological satellites covering the entire Earth is! One can, believe it or not, scan said data and see how the variables compare without doing "millions of pages of computer code".
When I prepared my own solar data (sunspot group area, magnetic intensity, solar flare occurrence) in 1980 in preparation for my first paper ('SID Flares and Sunspot Morphology', in Solar Physics, Vol. 88, Nos. 1-2, Oct. 1983) I could easily see how the data was trending and the extent of the correlations even before the first multivariate analysis was done on the university's IBM computer. But it is in Huber's interest to portray the task of ascertaining real global warming as some horrendously vast, complex task accessible only to certain high priests of climate science.
Huber then writes:
"And then it ends with a great leap back to simplicity. The atmosphere grew somewhat warmer in the 20th century. How do we know that human carbon emissions were the cause? Supposedly because the models are scientifically sound, they can't track the temperature changes back to volcanoes, solar variations or any other natural cause so the cause must be us."
Again, disingenuous! As readers may recall, Mount Pinatubo erupted in 1992. This volcanic event reduced global warming effect for up to 2-3 years after and this has been well-documented in numerous sources, as any goolging foray will show. Thus, a period of temperature change (decrease) has been tracked to a specific volcanic event.
More recently, we are aware of much of the worst heating from global warming being concealed by the phenomenon of global dimming. The effect was first spotted by Gerry Stanhill, an English scientist working
in Israel. Comparing Israeli sunlight records from the 1950s with current
ones, Stanhill was astonished to find a large fall in solar radiation.
"There was a staggering 22% drop in the sunlight, and that really amazed
me," he says.
Intrigued, he searched out records from all around the world, and found the
same story almost everywhere he looked, with sunlight falling by 10% over
the USA, nearly 30% in parts of the former Soviet Union, and even by 16% in
parts of the British Isles. Although the effect varied greatly from place to
place, overall the decline amounted to 1-2% globally per decade between the
1950s and the 1990s.
The most alarming aspect of global dimming is that it may have
led scientists to underestimate the power of the greenhouse effect.
While it's known how much extra energy has been trapped in the Earth's atmosphere
by the extra carbon dioxide (CO2), it's surprising is that it has so far translated to a temperature rise of just 0.6°C.
The most worrisome aspect, as a PBS docmentary (2004) by the same title showed, is that once the aerosols and pollutants spawning dimming are removed, the heating of Earth may attain unprecedented proportions of more than 5C in a century.
Thus, Huber's sarcastic reference to the Earth getting "somewhat warmer" is precisely because of global dimming obscuring the most pronounced effects.
As for tracking temperature changes back to variations on the Sun, this has also been done and quite extensively.
In fact, an exhaustive series of studies of temperature - solar sunspot number correlations have already been done and they are listed in the monograph 'Sun, Weather & Climate', by John R. Herman and Richard A. Goldberg, Dover, 1978, p. 127 - Table 3.5)
A total of eight periods are listed under column three, with their correlation coefficients, which include:
1891- 1917 (-0.44)
1870 - 1918 (-0.33)
1893 - 1924 (-0.25)
1888 - 1920 (- 0.24)
1892 - 1920 (-0.38)
1862 - 1920 (-0.33)
1867- 1923 (-0.46)
1871 - 1920 (-0.38)
Note that all entries exhibit a negative correlation coefficient, indicating an inverse relationship between sunspot number and temperature. Meanwhile for Period 2 (Column 4) the Table shows:
1925 - 1957 (- 0.1)
1921 - 1954 (+0.21)
1926 - 1954 (+0.32)
1921 - 1947 (+0.16)
1921 - 1950 (- 0.29)
1921 - 1953 (+0.24)
1924 - 1953 (+0.10)
1921 - 1950 (+0.23)
These coefficients mostly disclose positive correlation, the exception being the 6th entry from top. The authors note (cf. p. 128) that for the entire data set "the correlation coefficient for annual temperature and sunspot number (11-yr. cycle) was -0.38 up to 1920, but for the period 1921- 1950 the correlation had reversed and the coefficient was +0.23".
I maintain these results are totally consistent with the hypothesis of anthropogenic global warming. In their respective papers seeking to mitigate human responsbility in global warming, S.I. Akasofu, and earlier Sallie Baliunas and Willie Soon argued the opposite, but they forgot - or neglected to factor in - the 100 year delay time for CO2 deposition and retention in the atmosphere. Thus, inputs at the time of the onset of the industrial revolution, ca. 1845, would not manifest significantly until 100 years later.
And indeed, we see the inversion of averaged correlation coefficients from -0.38 (up to 1920) to +0.23 up to 1950, a total net change of +0.61 in the positive direction, which can take into account a total variability (explained by it) of some 36% (the total change - squared). It is clear, certainly to me, that Akasofu, Baliunas and Soon have drawn exactly the wrong conclusion from their respective results. Indeed, in the latter’s paper ( Fig. 1), showing the IPCC data and the temp. rise of 0.4C between 1910-1940, the accumulation of CO2 in the atmosphere is surely taken into account. Their conclusion that “the 'CO2' signal does not commence until 1940” is precisely what is in error.
This sort of error, neglecting time delay for signal exposure, is not unique and has been made many times by professionals who should know better. As well by students I have taught. (Though I can understand it more plausibly in the latter. It is just ironic that it is made in a paper purporting to overturn or at least dilute the IPCC results.)
In addition to the preceding work, Solar physicist John Eddy, made it his research specialty to study long-term solar variations connected to climate change, noted the period of 12th century warming in his book, ‘The New Solar Physics’, AAAS Selected Symposium, Westview Press, 1979, p. 17.
Eddy noted that this coincided with a period of higher solar activity (i.e. more sunspots) and possibly greater luminosity – on account of the fact that the irradiance is amplified around sunspots owing to redirection of convective heat flow. (Bear in mind the plasma in spots is at lower temperatures, by about 1500C, because of the powerful magnetic fields in them).
During solar cycle 20 – when I also conducted investigations on solar flares and their effects- the then Solar Max satellite used an active cavity radiometer to measure temperature increases arising from higher activity – especially as generated by more convection at the periphery of large spots. The differential was something on the order of 0.1C at the Sun! Since the radiant energy must now transit 150 million kilometers, and its intensity falls off as the inverse square, one can see this would translate into negligible increases at Earth.
What about longer period increases in solar luminosity associated with its possibly being a variable star – as opposed to sporadic sunspot outbursts?
The maximal magnitude of inherent solar -induced climate variability was probably first highlighted by Sabatino Sofia et al in their paper 'Solar Constant: Constraints on Possible Variations Derived from Solar Diameter Measurements', in Science, Vol. 204, 1306, 1979. Their estimate was a solar change in irradiance of roughly 0.1 % averaged over each solar cycle. (Irradiance is a measure of the energy per square meter received from the Sun).
Thus – if the solar irradiance effect at Earth (solar constant) is normally about 1360 watts/m^2, this would imply an increase of roughly 1.36 W/m^2.. The problem is that there is no observational evidence to support this in the warming period of the 12th century, or any time in the past century – when global warming spiked to serious levels. (Some like Sofia have argued that even if it had occurred, it would only engender a temp. increase contribution of perhaps one-fourth of one degree, or significantly less than what has been documented.
More recent space-based observations appear to show a variation in solar irradiance of at least 0.15% over the standard 11-year solar cycle. (E.g. Parker, E.N., Nature, Vol. 399, p. 416). However, even with this higher percentage ascribed to solar changes, the heating effect is nowhere near comparable to that induced from man-made global warming. (See, e.g. Martin I. Hoffert et al, in Nature, Vol. 401, p. 764).
As the authors in the latter study point out, the heating component arising from greenhouse gas emissions from 1861-1990 amounted to anywhere from 2.0 to 2.8 watts per square meter. The solar variability component detected over the same period amounted to 0.1 to 0.5 watts per square meter. Thus, even the MAXIMUM solar variability amounted to only a fraction (25%) of the MINIMUM power input from human-induced greenhouse warming!
Thus, we see how on all these points, Huber is proven wrong. We can indeed track temperature changes to natural events on Earth (e.g. volcanoes) as well as solar variations, and we see that the magnitudes of these are not enough to account for higher temperatures on Earth, but can conceal the most aggravated and enhanced effects (as in the case of volcanic eruptions and global dimming).
Huber through his piece refers to skeptic scientist Richard Lindzen of MIT, but who is Lindzen after all? He is a meterologist (not specifically a CLIMATE scientist - who typically take longer views) who was one of 100 signers of a petition to the effect man-made global warming is a "fallacy". What is not said, ever, is that these pitiful 100 contrarians are a minuscule fraction of the more than 20,000 working climate scientists who have published more than 15,000 papers validating the phenomenon of anthropogenic warming over the past ten years.
Indeed, the largest scientific organization on the planet - the American Geophysical Union - includes its position statement on human-induced warming as part of its public policy web page:
http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml
Another suspicious "petition" that has made the rounds is the so-called "Oregon Petition". (I actually received a question about it on the all experts site). The questioner made reference to the "17,000 names" on the petition, all allegedly sicentists but he or she evidently never took note that nearly all the names were fake. Names like "Perry Mason", John Grisham" et al, none of whom were scientists, none of whom were willing signees. The name at the front was "Edwin Teller" but everyone knows he is no climate scientist and his most recent accomplishment was promoting the specious "SDI" or 'Strategic Defense Initiative' in the 1980s - where high-powered lasers and particle beam weapons were to be mounted to satellites to shoot down ICBMs. All nonsense, shown to be bunkum by the American Physical Society's 'Directed Energy Weapons' study (Physics Today, May, 1987)
Lastly, Huber insists that: "Few college graduates, let alone school children, have the sicentific background to think critically about any of this".
This is more codswallop. Merely because I myself can't process of validate a process, or phenomenon or engineering device doesn't necessarily mean I reject its use or accept it as what it is claimed. I have no remote notion of how robotics works to produce something like the Japanses animatronic robot (who dances and performs human gestures) but that doesn't mean I am skeptical to the point of thinking it's a fake and there's really a little man inside a suit!
Nonetheless, any college graduate can certainly look for certain key attributes when approaching something like global warming claims, and look for these criteria:
1- How many sources does it come from? If only one source, of course one must suspect the claims! If from hundreds of peer-reviewed papers, there is a powerful reason to accept the claims.
2- What is the pedigree of the sources? If in such fare as The Journal for Geophysical Research, this is a powerful commendation for validity, but if in a private organization's web paper (like the George C. Marshall Institute, a free market think tank) it isn't. Why? Because the latter is operated by economists, lobbyists and dedicated to an ideological viewpoint that has not been vettted by SCIENCE.
3- What proportion of experts agree to the claims, as opposed to the contrarians who do not? In the case of Lindzen and his cohort of 100, this is a tiny fraction of the 20,000 climate scientists worldwide who had a hand in formulating the AGU position statement shown earlier.
In the end, no "faith" in man-made global warming is being promoted or needed, contrary to Huber's take. One can, motivated by sufficient intelligence and curiosity, obtain enough climatology papers and - with a basic background in general physics - ascertain for oneself that global warming is real, and occurring.
It is now past time for the skeptics to cease their nonstop recitation of red herrings vis-a-vis anthropogenic global warming. As writer Terry Black put it in hius recent Mensa Bulletin article, 'Never Trust A Skeptic' (Nov.-Dec., p. 32):
"It (global warming) has been repeatedly confirmed by the International Panel on Climate Change and the Nobel Prize Committee among many others. A purist might say 'it's still not proven', not beyond doubt. But I've reached the point where I've stopped doubting climate change and begun doubting the doubters, who seem ill-informed and intellectually dishonest. Only an idiot still doubts the Holocaust, or the moon landing. I submit that global warming is equally well-established."
Right on, Mr. Black!
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