‘Cosmoclimatology’ – tired old arguments in new clothes

On a more technical note, there seems to be inconsistencies between the GCR presented in Fig 2 and 3 in the A&G article (see red circles in the plot above), and this is not explained in the article. In Fig. 3 (left panel above) the GCR count increases by 10% but the maximum value is about 0% in Fig. 2 (right panel above), and the minimum value is abut -18% in Fig 3 but only -13% in Fig 2. It seems as if Fig 2 & 3 were based on different data sources. To be fair, both GCR and ISCCP are continuously updated and revised. But I am surprised that routine update and revision would result in as large differences as seen here. It looks as if the curve has been readjusted at some stage, but it is then a bit strange that the curve representing the global lower cloud cover doesn’t seem to have been re-scaled: the difference between maximum and minimum is about 3% in both figures (it’s annoying that the vertical axis for the cloud cover are given in different units in Fig.2 & 3). Is this important? I don’t know. But it could be a sign of sloppy work. There is not sufficient information about methodology that I could repeat the results presented here.

The adjusted cloud dataLow level clouds. Global ISCCP low cloud cover from IR measurements

Svensmark must have adjusted the cloud data too. Shown below is a figure from a previous paper where he justified an adjustment from a break in the difference between low and high clouds. The question is: why would the error be in the lower cloud measurements and not the high clouds? I haven’t seen any other independent statements about breaks or problems in the data series for low clouds after ~1995. Apparently, there are some biases in the ISCCP data, and Stordal et al. (2005) suggest that there is a spurious “footprint” from METEOSAT imprinted on the high (cirrus) clouds, and the problems with the ISCCP trends are now becoming well known. Besides, the fundamental error Marsh and Svensmark made in their ‘correction’ has discussed before, but since this issue keeps re-appearing, the ‘adjustment’ is shown again (left) while the ‘adjustment’ cannot be discerned in independent plots of the most recent data (right, and a second opinion sought in an independent analysis by K. Gislefoss).

In the A&G article, GCRs get the blame for the ‘snowball earth‘ episodes, and Svensmark writes:

A surprising by-product of this line of enquiry is a new perspective on changing fortunes of life over 3.5 billion years ago.

Extract from figure 4 in Svensmark 2007 Furthermore, the paper claims to explain the ‘faint sun paradox‘, by the complete absence of low clouds because there were allegedly no GCR at the time. Presumably, it is seriously meant. Proposing that the GCR is the only factor affecting low clouds, is inconsistent with the result shown in his very own Fig. 4 (the scatter plot shown left). In the A&G article, Fig 4 doesn’t really show the relationship between GCR and clouds, but between ion density and numbers of ultra-small (radius greater than 3 nano-meters) aerosol nucleation. The large scatter suggests that the number of ultra-small aerosols is fairly weakly affected by the number of ions – otherwise all the points would lie close to the diagonal line. This implies that other factors must influence the formation of ultra-small aerosols in addition to some effect due to ionization. And this is only in the laboratory environment – on the outside of Svensmark’s test chamber, more factors may play a role.

Page 3 of 5 | Previous page | Next page