Very true John, but with the vast majority of 20th century recording
stations being in our expanding urban areas, could rising temperatures a
la Global Warming be as much about increased sunshine, and the urban
heat island ,effect rather than climate change per se?

No. The urban heat island effect is, as far as I know, taken into account
when calculating the mean global temperature. This of course doesn't mean to
say that the temperature at the edge of a large town hasn't gone up, but that
it's not due to climate change.

Tudor Hughes, Warlingham, Surrey.