Just a short note this week to advise you of a new development in the field of atmospheric physics that, apart from an op-ed piece in the Financial Post by global warming maven Lawrence Solomon, probably won’t make it into the mainstream media at all.
Two years ago, I wrote the following in a draft paper (apologies for the lengthy citation, but as the climate change debate devolves upon actual science as opposed to opinion and invective, some explanation is required):
Apart from the obvious impact on climate of increased or decreased solar activity (i.e. more, or less, solar energy striking the Earth) the difficulty with the thesis that solar activity drives atmospheric temperatures was that no one had ever demonstrated experimentally a mechanism whereby this might be accomplished. That changed with the publication in 2006 of the results of a series of experiments at the Danish National Space Centre by physicist Henrik Svensmark and his team. Noting that colder climatic periods tended to correspond with low sunspot numbers (an indicator of solar activity, and the key observational metric employed in measuring solar activity cycles) Svensmark suggested that the Sun might exert an influence over terrestrial temperatures through the influence of solar activity on the intensity of galactic cosmic rays (GCR) striking the Earth.
Figure 10 - Comparison of tropospheric temperature with cosmic radiation flux
Geological evidence of periods of higher and lower cosmic ray bombardment – for example, the presence or absence of the Beryllium-10 isotope in rocks picked up by icebergs and deposited on the ocean floor (sometimes as far south as Africa) – suggested prima facie that periods of intense cosmic radiation corresponded with periods of intense cold.
Svensmark proposed that heavy cosmic rays – muons – are a key factor in the nucleation of low clouds because they are more likely to penetrate further into the atmosphere. During periods of intense solar activity, the solar wind pushes these particles away from Earth, inhibiting low cloud formation, leading to lower terrestrial albedo (reflectivity) and, therefore, greater warming. During periods of low solar activity, however, the solar wind is less intense, meaning that more cosmic rays impact the atmosphere, leading to higher rates of low cloud formation, resulting in a higher albedo (greater reflectivity), and therefore a cooler planet.
Svensmark and his team tested this idea in 2005 and obtained experimental results corroborating their hypothesis. Their work has since been buttressed by proposals offered by other elements of the space sciences, including – but not limited to – a significant correlation between prehistoric cooling periods and the passage of the Solar System through the spiral arms of the Milky Way Galaxy. According to a theory posited by Nir Shaviv, an astrophysicist at the Racah Institute of Physics in Jerusalem, the four major coolings that occurred during the half-billion-year span of animal life on Earth can be explained by the passage of the Solar System through the galactic spiral arms on its quarter-billion-year gavotte around the galaxy’s core. The cycle of passage through the spiral arms – which occurs roughly every 142 million years – may be augmented by the Solar system’s oscillation above and below the galactic plane, which further alters the exposure of the Earth to varying intensities of cosmic radiation.
Europe’s Centre d’Etudes pour la Recherche Nucleaire (CERN) is presently engaged in a much larger scale validation of Svensmark’s thesis called CLOUD09, testing a physical mechanism - proposed by Jasper Kirkby of the Center - whereby GCR may influence cloud nucleation, and providing archaeological data (in the form of radioisotopes) supporting this extension of the Svensmark thesis. Kirkby, citing Eichler et al., notes a 30-year time lag between GCR activity and temperature response, which corresponds to oceanic cycles, e.g. the Pacific and Atlantic oscillations (indicating a probable role for oceanic heat retention and release in influencing climate). It is also interesting that both the Medieval Warm Period and the Little Ice Age are visible in the Siberian temperature record from Eichler’s work, and are clearly correlated with the presence or absence of measured isotope ratios.
The mechanism postulated by Kirkby of course has yet to be demonstrated conclusively; one of the chief goals of the CLOUD09 experiment is to determine whether the proposed nucleation pathway actually works. However, by positing a causal mechanism and designing an experiment to test it, the GCR theorists - unlike the proponents of the AGW thesis - are following an empirical approach to obtaining corroboration of their hypothesis.
Well, that empirical approach has paid off. Last week, without fanfare (indeed, with the opposite of fanfare; prior to publishing the results of the CLOUD experiments, CERN’s management ordered CERN staff “to present the results clearly but not interpret them”), CERN published a brief statement outlining the results of the experiments, which have been underway for more than a decade. The results were published in a truncated fashion in Nature magazine (see here: http://www.nature.com/news/2011/110824/full/news.2011.504.html) using very tentative language, as might be expected from an actual scientist concerned about overreaching - but the fact that they were published at all is something of a victory. And, more to the point, the results constitute actual empirical evidence for a link between cosmic radiation and climate.
How convincing is the correlation? Just take a look at the CERN graph that Nature declined to publish:
The graph above does not appear in the print edition of Nature, but it does make showing at the back of the online supplementary material. The graph shows how cosmic rays promote the formation of clusters of molecules that can then grow and seed clouds in the real atmosphere.
At 03.45 am in a CLOUD experiment in Geneva, ultraviolet light began to create molecules in the cloud chamber, which approximates the air in the atmosphere. Jn above shows the neutral phase of the experiment, during which the CLOUD experiment electrically removed ions and molecular clusters. At 4.33 am, the CLOUD experiment stopped the electrical removal and allowed natural glalactic cosmic rays (Jgcr) to enter the chamber through the roof of the Geneva building, leading to a faster rate of cluster buildup.
Then, at 4.58 am, CLOUD also beamed charged pion particles (Jch) from an accelerator (these are equivalent to cosmic rays), the rate of cluster production took off, convincingly demonstrating the effect of cosmic rays on cluster growth.
In the graph above, the different colours show the different diameters of the clusters in nanometres. The blue clusters, which are smallest, grew fastest; the black ones, which are the largest, took the most time.
The graph makes it blatantly obvious that charged pions, equivalent to GCRs, are the most potent nucleating factor in cloud formation. Why is this important? Well, that’s simple. The IPCC completely rejects any significant role for the Sun in radiative forcing (RF) of climate, arguing that “natural forcings”, i.e. solar and volcanic effects, “are both very small compared to the differences in radiative forcing estimated to have resulted from human activities” (AR 4, WG1, Chapter 2, 137), and insisting that “increases in RF are clearly dominated by CO2.” (AR 4, WG1, Chapter 2, 208). The global circulation models (“climate models”) used to make the (failed) predictions of increased temperatures in response to increased CO2 concentrations (there is no statistically significant correlation between atmospheric CO2 and average global temperature over any time frame, recent or historical) cannot and do not model clouds - a crucial flaw, as clouds affect terrestrial albedo, and a mere 2% variance in cloud cover could explain all of the temperature change experienced over the past century. Kirkby and his colleagues, however, have found that GCR nucleation may account for “almost half” of cloud formation, indicating that “natural forcings” may indeed be the determining factor in climate change; and that they are in any case far more important a player in climate physics than atmospheric CO2 (and logically, therefore, more important than the 3% of atmospheric CO2 that is attributable to human activities).
There’s some circumstantial evidence for this, by the way; while CO2 concentrations in the atmosphere have increased steadily over the past decade, solar activity has dropped off markedly, with sunspot cycle 24 being extremely weak. Meanwhile, average global temperature has declined over the past decade. Correlation may not be causation, but when you’re looking for a causal relationship, you generally start by looking at phenomena that correlate, like solar activity and temperature, rather than those which - like carbon dioxide and temperature, for example - show no statistically significant correlation whatsoever. Come to think of it, maybe the decline in solar activity over the past decade is the reason why, contrary to the increasingly shrill babblings of the mavens of conventional wisdom, the Earth hasn’t been getting warmer, the Arctic won’t be ice-free any time soon, Greenland isn’t melting unusually, sea level rise is decelerating instead of accelerating, and we’re not all drowning in the gore - no pun intended - of the inevitable climate-change-driven bloodbath.
(For those interested in the non-link between climate and conflict, another of the favourite hobby-horses of the 'climate disruption' crowd, see http://thegwpf.org/the-climate-record/3274-bruno-tertrais-the-climate-wars-myth.html).
To put it more simply, if - as the CLOUD experiment suggests - the Kirkby-Svensmark thesis is correct, then all of the policies aimed at “stopping climate change” by controlling GHG emissions are useless and grotesquely costly nonsense. This has not, of course, stopped governments from pursuing them. Yet, anyway.
While it’s nice to see something I tried to highlight two years ago as being of potential interest to policymakers come to fruition, it would be nicer to see governments base their policy on actual empirical science as opposed to the shriekings of rent-seeking partisans. Of course, doing so would risk being subjected to their invective, which is becoming ever more extreme as support for their position continues to be eroded by empirical science. Just as “global warming” became “climate change” and then “global climate disruption” through the magic of etymorphology, “skeptic” has transmogrified into “denier” - and now, courtesy former VP Al Gore - into “racist.” [http://dailycaller.com/2011/08/28/gore-global-warming-skeptics-are-this-generations-racists/#ixzz1WQIX3SR0].
That’s sort of a funny position to take, coming from the side that wants to hold Nuremberg trials for skeptics. But I guess that’s just how Nobel Peace Prize winners “settle” scientific debates.
Here’s Solomon’s piece:
…and the Kirkby, et al., article in Nature:
…and the CERN graph that Nature left out of its piece: