On Thursday, October 29, 2015 at 8:35:51 AM UTC, wrote:
"jbm" wrote in message ...
I am absolutely and thoroughly stuck on something the local council has
asked me to look into.

Over the last seven years, the rainfall in this area has been well below
normal for 5 of them. Currently, we are over 300mm short of what we would
normally have expected in that time. Doesn't sound a lot, but it
represents 6 months of normal rainfall.

In 2011 we had just under 400mm, 60% of normal, and the following year,
despite numerous thunderstorms, deluges and flood alerts along the River
Nene, several springs in the area dried up, and have not flowed since.
Result = steams with no water in them, local lakes well below level, with
any pollution entering them not being diluted sufficiently not to cause
problems. One lake lost all its waterfowl in July due to contamination
from fuel oil from a local industrial estate. What I have found is enough
evidence to prove that the ground water levels are severely depleted, with
the water table at least 300mm below what it was 5 years ago.

So I would appreciate it if some of you knowledgeable meteorologists out
there would care to hazard a guess at the following. Having experienced so
many dry years recently, what are the chances of getting some
exceptionally wet ones, with steady and moderate rain to start
replenishing the ground water, without the majority of it disappearing
straight into the rivers as surface run-off? What we need is a lot of
water, and I mean a lot, getting down to that water table as quickly as
possible. Any ideas anyone? We have to make a decision shortly as to what
to do with the lakes - leave them as they are, dredge out all the ****e
and see what happens, or fill them in and be done with it. And a
reasonably intelligent prediction on future rainfall might help in that
decision.

jim

a very dry and rainless Northampton

Hi Jim, I'm soon to give a public lecture on Dartmoor weather. As part of
that I have been looking into climate change on Dartmoor. At Princetown in
the 20th Century annual rainfall significantly (as revealed by an objective
T test) decreased. In the 21st Century, evidence from Haytor would suggect
that that drying trend has slowed but not reversed. My take on this is that
our climate is slowly getting drier in terms of annual rainfall. Basically I
think you're ****ed!

Will
--
http://www.lyneside.demon.co.uk/Hayt...antage_Pro.htm
Will Hand (Haytor, Devon, 1017 feet asl)
---------------------------------------------

For Penzance:-

Mean Annual Rainfall
1961-1990 1140mm (call this 100%)
1971-2000 1182mm 104%
1981-2019 1219mm 107%
2000-2014 1228mm 108%

So a consistent upward trend, albeit gentle.

Nothing like the decrease in number of gales, which has been quite dramatic over the last 20 years.

Graham
Penzance