Number of the prominent AGW theorists have failed to explain the
Central England Summer-Winter Temperatures apparent 'paradox'

the 350 years long record of the CET the mid-summer temperatures has no notable rising trend, but one would be expected,

at least since 1950s if 'the GHG factor' was active.

 

the 350 years long record of the CET the mid-winter temperatures has an even rising trend, going back to 1660s, but that

would not be expected, at least not before say 1860s, some 200 years later, and to continue at the same rate after

1860 if 'the GHG factor' was active.

 

Temperatures for the months of June-July and December-January  are selected since they are symmetrically positioned around

the summer and the winter solstice, as the most significant dates in the annual climate oscillations  

More charts can be found here: Graphs and Formulae