Philip Eden wrote:


Peter, I remember a couple of days in September 1966 which were
foggy all day in my part of Bedfordshire. Usually, though, it was around
mid-October in Luton. In those days it seemed that the sky only had
to clear for an hour or so late-afternoon, and if the wind was F2 or less,
bang, the fog would clamp down.

Yes, the particulate pollution of domestic fires and industrial emissions
provided a far greater density of condensation nucleii in those days than
exists now.

Philip



Could this also be a contributory factor to our warming temperatures?
Loosely thinking just two days in Autumn that would have been foggy,
compared to none now would have made a difference of 3 to 4°c on the
daily maximum temperature, although arguably the clearer nights may lead
to colder radiation nights, in theory. Although as far as the grand
scheme of things goes the reduction in smoke is mainly confined to the
more developed European Countries and not to large parts of China, Asia,
etc.

--
Keith (Southend)
http://www.southendweather.net
e-mail: kreh at southendweather dot net