I had a look, but it's now the chart for the 24th. The "high" is still
there, but is now shown as 998mb. I think it's a case of a computer
algorithm getting over-enthusiastic, and labelling a very minor and
local peak as a "high". The main high pressure centre is well to the
west, as shown by the isobars. There's at least one other such
pseudo-high shown on the map, over Germany, and a pseudo-low just to the
west of Greenland.
-- John Hall
"The power of accurate observation is commonly called cynicism
by those who have not got it."
George Bernard Shaw
> I had a look, but it's now the chart for the 24th. The "high" is still
> there, but is now shown as 998mb. I think it's a case of a computer
> algorithm getting over-enthusiastic, and labelling a very minor and
> local peak as a "high". The main high pressure centre is well to the
> west, as shown by the isobars. There's at least one other such
> pseudo-high shown on the map, over Germany, and a pseudo-low just to the
> west of Greenland.
The median point is the 1016 mb line though much less that 8 either
side of it counts as col or misty stuff going nowhere.
Do you mean those 1025 thingies east of the 1043?
The Lows in the Arctic/North Atlantic are residual from the
earthquakes and Kenneth that spawned or/and increased during this
spell.
They should have congealed by now according the the T+12 and are
heading this way.
Which means another series of quakes starting up somewhere west of
Iceland and heading down to Indonesia via Japan.
The spell ends tomorrow (the lunar perigee was yesterday, I am still
pondering what happened with that.)
Take a look at Bernard Burton's site for the ASSX charts, don't be
misled by Google searching for brothels for you there though.
Perhaps he aught to change the title of that link. OTOH he will get
more hits with a sexy title.
I've posted some of the stuff I found, you know where -seek and ye
shall find.
Highs and lows are only defined relative to surrounding pressure and
are a human construct. There are no absolutes. The notation in this
instance merely marks the point of highest pressure in that locale.
Plus, yes, enthusiastic labelling.
On Nov 24, 1:04 pm, Stephen Davenport <step...@davenport.net> wrote:
> Highs and lows are only defined relative to surrounding pressure and
> are a human construct. There are no absolutes. The notation in this
> instance merely marks the point of highest pressure in that locale.
> Plus, yes, enthusiastic labelling.
Or maybe they were looking ahead?
A new spell starts tomorrow but look at T+24 anyway.
06:11 means fog with no Greenland High, not sure about the European
one though. The charts does not give the impression its constructors
were certain of themselves. And I've been waiting for a largish shoe
to drop.
Can't think why though. Just a gut feeling.
Ah, there we go, news just in:
6.2 2011/11/24 10:25:35 41.877 142.710 42.3 HOKKAIDO, JAPAN
REGION
On Nov 24, 1:04 pm, Stephen Davenport <step...@davenport.net> wrote:
> Highs and lows are only defined relative to surrounding pressure and
> are a human construct. There are no absolutes. The notation in this
> instance merely marks the point of highest pressure in that locale.
> Plus, yes, enthusiastic labelling.
> Stephen.
I would guess though that (at least in the N Hemisphere winter) that
lower central pressure "highs" are more likely further north over
Greenland/Iceland/Norway given the low mean surface pressure in this
region? ( e.g. http://badc.nerc.ac.uk/data/ecmwf-era/pics/mslp.gif )
On Nov 24, 1:53 pm, Richard Dixon <richsdixon1...@gmail.com> wrote:
> On Nov 24, 1:04 pm, Stephen Davenport <step...@davenport.net> wrote:
> > Highs and lows are only defined relative to surrounding pressure and
> > are a human construct. There are no absolutes. The notation in this
> > instance merely marks the point of highest pressure in that locale.
> > Plus, yes, enthusiastic labelling.
> > Stephen.
> I would guess though that (at least in the N Hemisphere winter) that
> lower central pressure "highs" are more likely further north over
> Greenland/Iceland/Norway given the low mean surface pressure in this
> region? ( e.g.http://badc.nerc.ac.uk/data/ecmwf-era/pics/mslp.gif)
> Richard
The High is not real anyway because MSL pressures over
the Greenland icecap are meaningless. The place only has "mean sea
level" at the edges and the interior is far too high for any
extrapolation to sea level to be useful. It's probably best to regard
Greenland as a discontinuity in the MSL pattern and to regard the
isobars as formalities which do not necessarily bear any relation to
the circulation at the land surface. The same is true of Antarctica,
even more so because of the greater extent and altitude of the
continent.
> On Nov 24, 1:53 pm, Richard Dixon <richsdixon1...@gmail.com> wrote:
> > On Nov 24, 1:04 pm, Stephen Davenport <step...@davenport.net> wrote:
> > > Highs and lows are only defined relative to surrounding pressure and
> > > are a human construct. There are no absolutes. The notation in this
> > > instance merely marks the point of highest pressure in that locale.
> > > Plus, yes, enthusiastic labelling.
> > > Stephen.
> > I would guess though that (at least in the N Hemisphere winter) that
> > lower central pressure "highs" are more likely further north over
> > Greenland/Iceland/Norway given the low mean surface pressure in this
> > region? ( e.g.http://badc.nerc.ac.uk/data/ecmwf-era/pics/mslp.gif)
> > Richard
> The High is not real anyway because MSL pressures over
> the Greenland icecap are meaningless. The place only has "mean sea
> level" at the edges and the interior is far too high for any
> extrapolation to sea level to be useful. It's probably best to regard
> Greenland as a discontinuity in the MSL pattern and to regard the
> isobars as formalities which do not necessarily bear any relation to
> the circulation at the land surface. The same is true of Antarctica,
> even more so because of the greater extent and altitude of the
> continent.
Sorry I missed your post Tudor.
I have since found the Canadian equivalent to the MetO's North
Atlantic. It encompasses most of the Northern Hemisphere short of
Russia:
I suspect the MetOffice has a chart just like that, their computer
modelling is (I have heard) better than most for a global run.
So it could be that such divvi punctuation is just over-run from
models that showed an Arctic High ridged down the Mid Atlantic. (aka
Greenland in this case.)
As it happened the suspected wasn't a large earthquake. IIRC it turned
into a tropical storm.
