delboy wrote:

there is good evidence that the climate has been variable before, with
naturally cold and warm periods. The fact that measured global
temperatures have increased by a fraction of a degree over the last
100 years, and the ice caps are melting, doesn't necessarily mean that
this will be a continuing trend.

Derek Copeland

This point has to be conceded. After an observation comes the stage of
attempting to associate it with other factors, in order to establish a
causal link. When the observation is global, modulating the links
thought to be causal is not easy, particularly when they cut through the
classical path to the improvement of National living standards in many
places.


Brian W