Len Wood wrote:
On Friday, October 30, 2015 at 11:52:04 AM UTC, Norman wrote:
Norman wrote:
Len Wood wrote:
On Friday, 30 October 2015 09:17:54 UTC,
One thing about Dartmoor, Graham has pointed out that gale frequency
has dropped right off and it is possible that the decrease in wind
speed has decreased the orographic enhancement (which is where we
get a lot of our rain). So it is perfectly possible for rainfall to
decrease or stay the same on high ground and increase on the coast,
especially in winter! Have winds speeds decreased in Plymouth like
Penzance?
Hi Len, again!
Having just read Jim's excellent response and queries in this thread,
I'm getting interested now in my own hypothesis which I'd dearly like
to test. If I gave you a list of "orographic enhancement days"
(moist SW'ly winds), would you be able to extract the Plymouth
rainfall (and wind) data for me? If we do this well it could end up
as a super paper? What do you think? Could be a lot of work for me
initially though to find the days, but that's science - hard work.
Will
--
http://www.lyneside.demon.co.uk/Hayt...antage_Pro.htm
Will Hand (Haytor, Devon, 1017 feet asl)
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1)Regarding dropbox, I don't think you have to sign up to get the files.
I might be wrong.
You will get a window appearing inviting you to sign up, but if you
wait a few seconds the file should appear anyway.
I will email you the file nevertheless Will.
2) Sadly Will, I do not have any wind data for Plymouth.
Historical wind datasets are extremely difficult to get hold of for
any station. They are often not hourly measurements, and are of
questionable use if not hourly.
The DWRs of course have some wind information up to 1980.
Len
Wembury
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--
Hourly obs from Mountbatten from Jan 1973 to the present day are
available for free from NCDC. A good starting point is
http://gis.ncdc.noaa.gov/map/viewer/...ourly&layers=1
Unfortunately, there is a bit of a glitch in the NCDC software. The winds
in their database are given in mph, converted from the original knots.
From time to time the software seems to think that the original report is
in m/sec so the mph conversion is spuriously high. Fortunately, the error
is sufficiently large for the spurious obs to be fairly easily identified.
If you need any assistance in getting to the data from the above link let
me know and I'll try to steer you through it.
I should have mentioned that the obs in the NCDC database are in a decoded
format suitable for import into a spreadsheet.
--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
http://peakdistrictweather.org
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Norman,
I've had trouble with the NCDC database before as it is not quality
controlled. I've cross checked the UKMO Mount Batten precipitation data with
NCDC data base and my own obs and found some alarming differences sometimes
in the daily data.
Still, it's all we've got as regards wind, so better than nothing.
Shame there is rarely any gust speeds given on NCDC.
Len
Wembury, SW Devon
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The original coded observations are available from OGIMET back to 1999.
It's a great pity that NCDC process the data before putting it onto their
database. An archive of the original coded observations would be much better,
even in the old SYNOP code for the older ones. I suppose modern day researchers
would bitch about not being able to understand the code.
--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
http://peakdistrictweather.org