Wednesday, March 16, 2016

(3B) footnotes: Profiles in Malicious Deception: Svensmark + 1000frolly


This is the footnotes to the third installment of my dissection of 1000frolly's malicious nonsense in his 1/25/16 YouTube video, "NASA - The "Mystery" of Antarctic Cooling," for an introduction please refer to the first installment.

This continues where #2A and #2B-footnotes left off.  While frolly is still trying to sell his cosmoclimatology and taking a few swipes at the IPCC, I've created this footnotes document full of evidence supporting my critique.  Ideally you can open both and view them side by side.
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{#15} "Because all this happened before human activity could have influenced the climate."
Right, solar cycles upon galactic cycles upon cosmic cycles - that adds up to nothing regarding the past few hundred years - meanwhile back on Earth:

Which produces more CO2, volcanic or human activity?
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How Much More Will Earth Warm?
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{#15b} "Because all this happened before human activity could have influenced the climate."
Sure, CO2 has been a major regulator since way back, here's some background.

Richard Alley - 4.6 Billion Years of Earth’s Climate History: The Role of CO2
National Academy of Sciences | Jun 1, 2015 |  24:00 min
NAS member Richard Alley presents on 4.6 Billion Years of Earth’s Climate History: The Role of CO2, during the Symposium—Earths, Moons, Mars & Stars at the National Academy of Sciences 152nd Annual Meeting.
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Richard Alley: "The Biggest Control Knob: Carbon Dioxide in Earth's Climate History"
Dan Moutal | Dec 10, 2012 | 57:00 min
From the 2009 AGO Fall meeting.
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Thing is, it doesn't matter where the CO2 comes from, physics is physics.
Did I Say 30 Billion Tons of CO2 a Year? I Meant 40.
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{#16} "... strong believers in the CO2 nonsense."
In your head.  It's the evidence that drives rational people towards accepting the facts.  

Coby does a nice straightforward job of explaining why the overwhelming evidence points to CO2 and greenhouse gases.  Definitely worth reading.

By coby | October 21, 2008

“What is the evidence that CO2 is causing global warming?”

... The simplest thing to say to that, is “go read the IPCC report”. It is very thorough and very meticulous. (See the latest one here, but I encourage beginners to use the more convenient HTML format of the 2001 report here (even though it is out of date on many details). But because my visitor did specify “in my own words” (pop quiz!) and it is a good question when sincerely posed, I will try to lay it out below. ...  

Just to pile on, here are some rather key specific observations beyond the rise in seasonally averaged global temperature that fit in well with an enhanced greenhouse effect (the relevant effect of increasing CO2 concentrations). These observations do not fit with other potential forcings.
  1. Temperatures have risen more at night than during the day. This really defeats the notion of a solar powered climate change on its face.
  2. The stratosphere is cooling. Models that predict the warming we are seeing also predict this particular feature of the current climate change.
  3. An increasingly enhanced greenhouse effect should cause an energy imbalance between incoming sunlight and outgoing infrared radiation. This has been detected.
So to summarize: we know anthropogenic climate change is real because there is no other likely candidate cause, the CO2 rise is unquestionably the result of our activities, the particulars of the warming signature are consistent with an enhanced greenhouse effect and the whole phenomenon is entirely consistent with very long standing theories and expectations.

If it looks like a duck, and it quacks like a duck, why on earth would you think it is a galactic cosmic ray?
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There is also direct observational evidence for this 'CO2 Theory':

First Direct Observation of Carbon Dioxide’s Increasing Greenhouse Effect at the Earth’s Surface
News release, Dan Krotz  • February 25, 2015

"... The scientists measured atmospheric carbon dioxide’s contribution to radiative forcing at two sites, one in Oklahoma and one on the North Slope of Alaska, from 2000 to the end of 2010. Radiative forcing is a measure of how much the planet’s energy balance is perturbed by atmospheric changes. Positive radiative forcing occurs when the Earth absorbs more energy from solar radiation than it emits as thermal radiation back to space. It can be measured at the Earth’s surface or high in the atmosphere. In this research, the scientists focused on the surface.

They found that CO2 was responsible for a significant uptick in radiative forcing at both locations, about two-tenths of a Watt per square meter per decade. They linked this trend to the 22 parts-per-million increase in atmospheric CO2 between 2000 and 2010. Much of this CO2 is from the burning of fossil fuels, according to a modeling system that tracks CO2 sources around the world. ..." 
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Ice Core Data Help Solve a Global Warming Mystery
By William Ferguson on March 1, 2013
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{#17 - this got lost and wasn't placed up where it belongs, so I'll slip it in here.} 
10:00 - It's actually really, really if you were starting climate change research from scratch you would start with this idea, because this is the null hypothesis."
Cosmoclimatology the "null hypothesis?"  Where's that one fly in from?  
Bet frolly can't explain it either, but it sure sounded sciencie.  
Seriously though, sounds like frolly don't fully understand what he's talking about.

     Explainer: what is a null hypothesis?
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     What is a null hypothesis in layman's terms?

Frolly, why not have your "null hypothesis" conform to known physics?

Global Warming: Understanding the Forecast
"Is a comprehensive introduction to all aspects of global warming. Written in an accessible way, and assuming no specialist prior knowledge, this book examines the processes that control climate change and climate stability, from the distant past to the distant future."
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{#18} "so the mixing of cause and effective, they've got it backwards."
Tis frolly who has it backward.  This cloud formation has never been demonstrated!  It's a product of Svensmark's personal convictions, but his claims are constantly undermined by cold facts.

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Beyond that, what frolly neglects to mention is that even if this 'might' actually happen, the lower atmosphere is flooded with way more appropriately sized cloud nucleation particles that already do the heavy lifting of cloud formation.  This process is well understood.

Cloud processing of mineral dust: direct comparison of cloud residual and clear sky particles during AMMA aircraft campaign in summer 2006  |  A. Matsuki, et al

Traces of heterogeneously formed secondary sulfate, chloride and nitrate were found on many dust particles (though fraction of sulfate may be present in the form of gypsum as primary dust component). These secondary species were particularly enhanced in clouds (i.e. cloud processing). The study illustrates that calcium-rich particles assumed to be carbonates (Calcite, Dolomite) contained the secondary species in significantly larger frequency and amount than the silicates (Quartz, Feldspar, Mica, Clay), suggesting that they represent the most reactive fraction of the mineral dust. 

A surprisingly large fraction of the Ca-rich particles were already found in deliquesced form even in clear-sky conditions, most probably reflecting their extreme hygroscopicity, resulting from their reaction with HNO3 gas.

Both silicate and Ca-rich particles were found dominant among the supermicron cloud residues, and they were supposed to be those previously activated as CCN. It is highly probable that the observed formation of soluble materials enhanced their cloud nucleating abilities. ...
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Atmospheric Aerosols: Composition, Transformation, Climate and Health Effects
Ulrich Pöschl | DOI: 10.1002/anie.200501122 | www.angewandte.org

Aerosols are of central importance for atmospheric chemistry and physics, the biosphere, climate, and public health. The airborne solid and liquid particles in the nanometer to micrometer size range influence the energy balance of the Earth, the hydrological cycle, atmospheric circulation, and the abundance of greenhouse and reactive trace gases. ...
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{#19} "IPCC - As we all know the IPCC totally ignore the sun."   
No they don't.

Climate Change 2007: Working Group I: The Physical Science Basis
TS.2.4 Radiative Forcing Due to Solar Activity and Volcanic Eruptions

Continuous monitoring of total solar irradiance now covers the last 28 years. The data show a well-established 11-year cycle in irradiance that varies by 0.08% from solar cycle minima to maxima, with no significant long-term trend. New data have more accurately quantified changes in solar spectral fluxes over a broad range of wavelengths in association with changing solar activity. Improved calibrations using high-quality overlapping measurements have also contributed to a better understanding. 

Current understanding of solar physics and the known sources of irradiance variability suggest comparable irradiance levels during the past two solar cycles, including at solar minima. The primary known cause of contemporary irradiance variability is the presence on the Sun’s disk of sunspots (compact, dark features where radiation is locally depleted) and faculae (extended bright features where radiation is locally enhanced). {2.7}

The estimated direct radiative forcing due to changes in the solar output since 1750 is +0.12 [+0.06 to +0.3] W m–2, which is less than half of the estimate given in the TAR, with a low level of scientific understanding. The reduced radiative forcing estimate comes from a re-evaluation of the long-term change in solar irradiance since 1610 (the Maunder Minimum) based upon: a new reconstruction using a model of solar magnetic flux variations that does not invoke geomagnetic, cosmogenic or stellar proxies; improved understanding of recent solar variations and their relationship to physical processes; and re-evaluation of the variations of Sun-like stars. While this leads to an elevation in the level of scientific understanding from very low in the TAR to low in this assessment, uncertainties remain large because of the lack of direct observations and incomplete understanding of solar variability mechanisms over long time scales. {2.7, 6.6}

Empirical associations have been reported between solar-modulated cosmic ray ionization of the atmosphere and global average low-level cloud cover but evidence for a systematic indirect solar effect remains ambiguous. It has been suggested that galactic cosmic rays with sufficient energy to reach the troposphere could alter the population of cloud condensation nuclei and hence microphysical cloud properties (droplet number and concentration), inducing changes in cloud processes analogous to the indirect cloud albedo effect of tropospheric aerosols and thus causing an indirect solar forcing of climate. 

Studies have probed various correlations with clouds in particular regions or using limited cloud types or limited time periods; however, the cosmic ray time series does not appear to correspond to global total cloud cover after 1991 or to global low-level cloud cover after 1994. Together with the lack of a proven physical mechanism and the plausibility of other causal factors affecting changes in cloud cover, this makes the association between galactic cosmic ray-induced changes in aerosol and cloud formation controversial. {2.7}
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Global warming is not due to the sun, confirms leaked IPCC report
December 14, 2012 | Dana Nuccitelli
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Solar Variability and Terrestrial Climate
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{#20} "Because of course there's no money available to research solar activity in relation to the climate."
List of some Solar observing satellites - climatologists are fully aware of and engaged with these projects and the information they produce:


(History of) the Exploration of the Magnetosphere
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{#21} "All (IPPC) count is a little bit of TSI and ignore everything else."
Nonsense, of course if he ignores the IPCC report, he'll never know about this more complete picture.  (my highlights)

Chapter 10 IPCC WGI Fifth Assessment Report
Final Draft (7 June 2013) 

Box 10.2: The Sun’s Influence on the Earth’s Climate

A number of studies since AR4 have addressed the possible influences of long term fluctuations of solar irradiance on past climates, particularly related to the relative warmth of the Medieval Climate Anomaly (MCA) and the relative coolness in the Little Ice Age (LIA). There is medium confidence that both external solar and volcanic forcing, and internal variability, contributed substantially to the spatial patterns of surface temperature changes between the MCA and the LIA, but very low confidence in quantitative estimates of their relative contributions (Sections 5.3.5.3, 5.5.1). The combined influence of volcanism, solar forcing and a small drop in greenhouse gases likely contributed to northern hemisphere cooling during the LIA (Section 10.7.2). Solar radiative forcing from the Maunder Minimum (1745) to the satellite era (average of 1976– 2006) has been estimated to be +0.08 to +0.18 W m–2 (low confidence, Section 8.4.1.2). This may have contributed to early 20th century warming (low confidence, Section 10.3.1).

More recently, it is extremely unlikely that the contribution from solar forcing to the observed global warming since 1950 was larger than that from greenhouse gases (Section 10.3.1.1.3). It is very likely that there has been a small decrease in solar forcing of –0.04 [–0.06 to –0.02] W m–2 over a period with direct satellite measurements of solar output from 1986 to 2008 (Section 8.4.1.1.1). There is high confidence that changes in total solar irradiance have not contributed to global warming during that period.

Since AR4 there has been considerable new research that has connected solar forcing to climate. The effect of solar forcing on GMST trends has been found to be small, with less than 0.1°C warming attributable to combined solar and volcanic forcing over the 1951–2010 period (Section 10.3.1), although the 11 year cycle of solar variability has been found to have some influence on GMST variability over the 20th century. GMST changes between solar maxima and minima are estimated to be of order 0.1°C from some regression studies of GMST and forcing estimates (Figure 10.6) although several studies have suggested these results may be too large due to issues including degeneracy between forcing and with internal variability, overfitting of forcing indices, and underestimated uncertainties in responses (Ingram, 2007; Benestad and Schmidt, 2009; Stott and Jones, 2009). Climate models generally show less than half this variability (Jones et al., 2012).

Variability associated with the 11-year solar cycle has also been shown to produce measurable short-term regional and seasonal climate anomalies (Miyazaki and Yasunari, 2008; Gray et al., 2010; Lockwood, 2012; National Research Council, 2012) particularly in the Indo-Pacific, Northern Asia and North Atlantic regions (medium evidence). For example, studies have suggested an 11-year solar response in the Indo-Pacific region in which the equatorial eastern Pacific sea surface temperatures (SSTs) tend to be below normal, the sea level pressure (SLP) in the Gulf of Alaska and the South Pacific above normal, and the tropical convergence zones on both hemispheres strengthened and displaced polewards under solar maximum conditions, although can be difficult to discriminate the solar-forced signal from the El Niño-Southern Oscillation (ENSO) signal (van Loon et al., 2007; van Loon and Meehl, 2008; White and Liu, 2008; Meehl and Arblaster, 2009; Roy and Haigh, 2010; Tung and Zhou, 2010; Bal et al., 2011; Haam and Tung, 2012; Hood and Soukharev, 2012; Misios and Schmidt, 2012; Roy and Haigh, 2012). 

For northern summer, there is evidence that for peaks in the 11-year solar cycle, the Indian monsoon is intensified (Kodera, 2004; van Loon and Meehl, 2012), with solar variability affecting interannual connections between the Indian and Pacific sectors due to a shift in the location of the descending branch of the Walker Circulation (Kodera et al., 2007). 
Additionally, model sensitivity experiments (Ineson et al., 2011) suggest that the negative phase of the North Atlantic Oscillation (NAO) is more prevalent during solar minima and there is some evidence of this in observations, including an indication of increased frequency of high pressure ‘blocking’ events over Europe in winter (Barriopedro et al., 2008; Lockwood et al., 2010; Woollings et al., 2010).

Two mechanisms have been identified in observations and simulated with climate models that could explain these low amplitude regional responses (Gray et al. (2010); medium evidence). These mechanisms are additive and may reinforce one another so that the response to an initial small change in solar irradiance is amplified regionally (Meehl et al., 2009) The first mechanism is a top-down mechanism first noted by Haigh (1996) where greater solar ultraviolet radiation (UV) in peak solar years warms the stratosphere directly via increased radiation and indirectly via increased ozone production. 

This can result in a chain of processes that influences deep tropical convection (Balachandran et al., 1999; Shindell et al., 1999; Kodera and Kuroda, 2002; Haigh et al., 2005; Kodera, 2006; Matthes et al., 2006). In addition, there is less heating than average in the tropical upper stratosphere under solar minimum conditions which weakens the equator-to-pole temperature gradient. This signal can propagate downward to weaken the tropospheric midlatitude westerlies, thus favoring a negative phase of the AO or NAO. This response has been shown in several models (e.g., Shindell et al., 2001; Ineson et al., 2011) though there is no significant AO or NAO response to solar irradiance variations on average in the CMIP5 models (Gillett and Fyfe, 2013).

The second mechanism is a bottom-up mechanism that involves coupled air-sea-radiative processes in the tropical and subtropical Pacific that also influence convection in the deep tropics (Meehl et al., 2003; Meehl et al., 2008; Rind et al., 2008; Bal et al., 2011; Cai and Tung, 2012; Zhou and Tung, 2013b). Such mechanisms have also been shown to influence regional temperatures over longer time scales (decades to centuries), and can help explain patterns of regional temperature changes seen in paleoclimate data (e.g., Mann et al., 2009; Section 10.7.2; Goosse et al., 2012b) although they have little effect on global or hemispheric mean temperatures at either short or long timescales.

A possible amplifying mechanism linking solar variability and the earth’s climate system via cosmic rays has been postulated. It is proposed that variations in the cosmic ray flux associated with changes in solar magnetic activity affect ion-induced aerosol nucleation and cloud condensation nuclei (CCN) production in the troposphere (Section 7.4.6). A strong solar magnetic field would deflect cosmic rays and lead to fewer CCN and less cloudiness, thereby allowing for more solar energy into the system. 

Since AR4 there has been further evidence to disprove the importance of this amplifying mechanism. Correlations between cosmic ray flux and observed aerosol or cloud properties are weak and local at best, and do not prove to be robust on the regional or global scale (Section 7.4.6). Although there is some evidence that ionization from cosmic rays may enhance aerosol nucleation in the free troposphere, there is medium evidence and high agreement that the cosmic ray-ionization mechanism is too weak to influence global concentrations of CCN or their change over the last century or during a solar cycle in any climatically significant way (Sections 7.4.6, 8.4.1.5). 

The lack of trend in cosmic ray intensity over the 1960–2005 period (McCracken and Beer, 2007) provides another argument against the hypothesis of a major contribution of cosmic ray variations to the observed warming over that period given the existence of short timescales in the climate system response.

Thus, although there is medium confidence that solar variability has made contributions to past climate fluctuations, since the mid-20th century there has been little trend in solar forcing. There are at least two amplifying mechanisms that have been proposed and simulated in some models that could explain small observed regional and seasonal climate anomalies associated with the 11-year solar cycle, mostly in the Indo-Pacific region and northern mid to high latitudes.

Regarding possible future influences of the sun on earth’s climate, there is very low confidence in our ability to predict future solar output, but there is high confidence that the effects from solar irradiance variations will be much smaller than the projected climate changes from increased radiative forcing due to GHGs (Sections 8.4.1.3, 11.3.6.2.2).
[END BOX 10.2 HERE]

Based on a range of detection and attribution analyses using multiple solar irradiance reconstructions and models, Hegerl et al. (2007b) concluded that it is very likely that greenhouse gases caused more global warming than solar irradiance variations over the 1950–1999 period. 

Detection and attribution analyses applied to the CMIP5 simulations (Figure 10.4) indicate less than 0.1 K temperature change attributable to combined solar and volcanic forcing over the 1951–2010 period. Based on a regression of paleo temperatures onto the response to solar forcing simulated by an energy balance model, Scafetta and West (2007) find that up to 50% of the warming since 1900 may be solar-induced, but Benestad and Schmidt (2009) show this conclusion is not robust, being based on disregarding forcings other than solar in the preindustrial period, and assuming a high and precisely-known value for climate sensitivity. 

Despite claims that more than half the warming since 1970 can be ascribed to solar variability (Loehle and Scaffetta, 2011) , a conclusion based on an incorrect assumption of no anthropogenic influence before 1950 and a 60 year solar cycle influence on global temperature (see also Mazzarella and Scafetta, 2012), several studies show that solar variations cannot explain global mean surface warming over the past 25 years, since solar irradiance has declined over this period (Lockwood and Fröhlich, 2007; Lockwood, 2008; Lockwood and Fröhlich, 2008; Lockwood, 2012). Lean and Rind (2008) conclude that solar forcing explains only 10% of the warming over the past 100 years, while contributing a small cooling over the past 25 years. 

Thus while there is some evidence for solar influences on regional climate variability (Box 10.2) solar forcing has only had a small effect on GMST. Overall, we conclude that it is extremely unlikely that the contribution from solar forcing to the warming since 1950 was larger than that from greenhouse gases.

A range of studies have used statistical methods to separate out the influence of known sources of internal variability, including ENSO and, in some cases, the AMO, from the response to external drivers, including volcanoes, solar variability and anthropogenic influence, in the recent GMST record: see, for example, Lockwood (2008), Lean and Rind (2009), Folland et al. (2013 ), Foster and Rahmstorf (2011) and Kaufmann et al. (2011). Representative results, as summarised in Imbers et al. (2013) are shown in Figure 10.6. 

These consistently attribute most of the warming over the past 50 years to anthropogenic influence, even allowing for potential confounding factors like the AMO. While results of such statistical approaches are sensitive to assumptions regarding the properties of both responses to external drivers and internal variability (Imbers et al., 2013), they provide a complementary approach to attribution studies based on global climate models.

Overall, given that the anthropogenic increase in greenhouse gases likely caused 0.5°C–1.3°C warming over 1951–2010, with other anthropogenic forcings probably contributing counter-acting cooling, that the effects of natural forcings and natural internal variability are estimated to be small, and that well-constrained and robust estimates of net anthropogenic warming are substantially more than half the observed warming (Figure 10.4) we conclude that it is extremely likely that human activities caused more than half of the observed increase in GMST from 1951–2010.   {LINK}
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{#22} "Now for this theory of cosmoclimatology which main stream scientists have apparently hardly ever even heard of."  
Another lie.  Experts certainly have given Svensmark's ideas and suggestions a good deal of thought.  

What irritates Svensmark and echo-chamber pals, is that serious scientific review has consistently revealed glaring weaknesses in Svensmark's work and his train of logic.  
Allow Dr. Benestad to explain.

‘Cosmoclimatology’ – tired old arguments in new clothes

In a recent issue of the journal Astronomy and Geophysics (A&G), Henrik Svensmark coined a new term: ‘cosmoclimatology’ . I think ‘cosmoclimatology’ is a good and refreshing name for anything combining our cosmos with our climate. However, all other aspects of the article I found very disappointing. We have already covered most of these topics before, but the A&G articles provides us with some new aspects to discuss. 

Furthermore, Svensmark is the Director for Center for Sun-Climate Research, Danish National Space Center, and therefore influential. He is also the co-author of a recent book with Nigel Calder that received some attention. Furthermore, a laboratory experiment of his also managed to make some headlines. It seems that solar forcing is one of the sceptics’ last trenches in the debate about climate change. In my view the A&G paper therefore merits a comment as long as the same old and worn arguments resurface without discussing misgivings from the critics.

There are a number of issues which really make the A&G paper poor in my view. One is the neglect in addressing old criticisms of the hypothesis that galactic cosmic rays (GCR) change our climate by modulating clouds (see here, here, & here). Svensmark is very vague on the lack of any trend in GCR or other solar proxies since 1952. 

I confronted him about this question on an European Geophysical Society (EGS)conference in Nice a few years ago, and have since published a paper also making the point. The A&G article makes selective references, without answering the serious criticism forwarded by Damon & Laut (2004), Laut (2003), or myself. To be fair, the critical paper by Kristjansson and Kristiansen (2000) is cited, albeit only to say that Svensmarks’s own conclusion is “a counter-intuitive finding for some critics“. The remaining treatment of critical aspects is completed in the A&G article without further qualifications other than the following passage (my emphasis):

The chief objection to the idea that cosmic rays influence cloudiness came frommeteorologists who insisted that there was no mechanism by which they could do so. On the other hand, some atmospheric physicists concluded that observation and theory had failed to account satisfactorily for the origin of aerosol particles without which water is unable is unable to condense to make clouds.

I don’t think this is meant as a joke, and I don’t know if the article tries to make a point about classifying critics and supporters of his ideas as ‘meteorologists’ and ‘physicists’ (I’m a physicist). But that’s a tiny detail compared to the more substantial misconceptions embedded in this passage. There are plenty of ‘seeds’ in the air on which water can form, also known as cloud condensation nuclei (CCN). According to my old text book ‘A Short Course in Cloud Physics’ by Rogers and Yau (1989, p. 95 in Third edition): “Condensation nuclei of some sort are always present in the atmosphere in ample numbers: clouds form whenever there are vertical air motions and sufficient moisture”. The CCN tend to consist of mineral dust, sea salt, or sulphur-based matter.

I have serious misgivings concerning the following – vague yet false – statement put forward in the A&G article :

Attempts to show that certain details in the climatic record confirm the greenhouse forcing (e.g. Mitchell et al., 2001) have been less conclusive. 
By contrast, the hypothesis that changes in cloudiness obedient to cosmic rays help to force climate change predicts a distinctive signal that is in fact very easily observed, as an exception that proves the rule.

Again, no further qualifications or references. The irony is that Svensmark ignores (in addition to the lack of trend in GCR) the fact that the night-time temperature has risen faster than the day-time temperature, which I did pester him about on a Nordic Meteorology Meeting in Copenhagen in 2002. A journalist from Jyllands Posten present at the conference got the message, as my criticism was echoed in a news report the following day (“Klimaforskere i åben krig” [translation ‘Climate researchers in open war’], May 28, 2002): It’s tricky to explain how a warming caused by decreasing albedo would be stronger at the night-side (dark) of the planet.

Another newer puzzle is the surprisingly good correlation between low clouds and GCR (se figure below), since higher clouds (global mean cover ~13%) ormiddle clouds (~20%) which are not influenced by GCR, mask the lower ones(which represents between 28% and 30% of the globe). It’s indeed a surprisingly good fit between the two curves in the A&G article (reproduced below), considering the time structure of both the high-cloud, middle-cloud, and low-cloud curves, and the satellites cannot see the low-level clouds where there are higher clouds above blocking the view. The fact that the variations are small (~1% amplitude!) compared to the total area, suggest that the overlap/masking effect by the higher cloud must be very small for a high correlation to shine through the upper clouds. Even if the clouds hypothetically were completely determined by GCR, one would expect to see deterioration of the correlation if viewed from above due to the presence of higher clouds not influenced by GCR. Another issue is that the cloud data used in this analysis was only based on the infra-red (IR) channel, and a better analysis would include the visible observations too, but if the visible data are included, then the correlation is lower (private communications, Jørn Kristjansen). ...


This is only half the article, plenty more interesting details at:http://www.realclimate.org/index.php/archives/2007/03/cosmoclimatology-tired-old-arguments-in-new-clothes/
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Also see: 
This is what a scientist sounds like, Dr. Randall on Clouds and such.