The War of the Graphs - Climate Change: Identification and Projections - page 37

Figure 3.6. Lines by [FRI 91], modified and
expanded by [STA 11]
This figure looks to deal a decisive blow against the theory of solar
origins of warming, disproving the initial correlation with the final
divergence 13 . In reality, the final gaps are scarcely greater than those which
can be seen in Figure 3.4 (b) around the years 1000 or 1600, and do not
challenge the correlation of large millennia-long climatic variations with
solar irradiance.
Taking a closer look, the variations of the two lines 3.4 (b) are more often
synchronized than not. The period 1980-2010 is simply in the part where the
lines do not correlate. Looking even closer, (see Figure 7.4 below), a
correlation appears between the Schwabe solar cycles (11 years) and
temperatures.
In any case, the basis of all of these debates is inconsistent for a number
of reasons. The first of which is that it is overly simplistic to polarize a
theory towards a single cause: either “100% CO 2 ” or “100% solar”.
13 The Frohlich and Lean correction (see Figure 2.10) in fact helps to accentuate the eventual
divergence.