"Len Wood" wrote in message
...
On Jun 7, 10:43 am, "Anne Burgess"
wrote:
Quite right Will. Cloud is fog if you are standing with your
head in
it. Dartmoor probably does qualify as the foggiest area if you
count
the number of people living there. Not just the hill farmers.
Poor
sods. There is Princetown for a start at 2000 ft.
Len Wood

By that logic, Cairn Gorm wouldn't be the windiest place in
Britain. Nor would any mountain summit or lighthouse, come to
that. So where would be?

Also how would you do the calculation? Would 24 hours of fog on
Dartmoor count as less foggy than one minute of fog in London?
There are far more than 24x60 times the number of people in
London than there are on Dartmoor.

Anne

OK Anne,
I was just addressing the issue of when is it fog or just high ground
shrouded in cloud?
It is always going to be called cloud unless you are walking about in
it. So fog is about visibility, which involves the human eye.
However, as good scientists we should be referring to the formation
method. Here we are talking about orographic fog, which I would
suggest is more common than radiation fog or even advection fog,
simply because low cloud is more ubiquitous than these.
Now, does the average person on the ground care about the way it has
been formed. I think not, and the mass media wants as usual to keep
things simple.

There are certainly quite a few more people in London than there are
on Dartmoor, for which we can be eternally grateful.
I agree it sounds a bit crazy putting a human element into
meteorological data. But it is of interest in impact studies.

Len
=========

Today we have had cloud and outbreaks of heavy rain and guess what ....
at 1700 it is thick fog and still raining. Dartmoor does get a lot of fog
due to its proximity to airmasses with high specific humidity straight off
the Atlantic.

PS Len, Princetown is at 1400 feet not 2000 feet, still plenty high enough
to get guaranteed decent snow in winter and pleasant cool summers and a bit
of fog from time to time grin.

Of course that is a million miles from BBC TV Weather Centre weather :-)

Will (A happy Dartmoor resident)
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