Met Met Office explanation of Heathrow record
 

Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

Met Met Office explanation of Heathrow record
 

On Tuesday, July 7, 2015 at 3:01:29 PM UTC+1, Scott W wrote:
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

Thanks Scott. Really interesting.

Met Met Office explanation of Heathrow record
 

On Tuesday, 7 July 2015 15:01:29 UTC+1, Scott W wrote:
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

A good explanation. I didn't think so many local records had been broken and over so wide an area, though it didn't break mine (32 yrs). My max was 33.8°C but 19 July 2006 had 35.0°C.
It seems to me that a large majority of the public are suspicious of Heathrow readings ("all that tarmac, all those engines") but without justification.

Tudor Hughes, Warlingham, Surrey. 557 ft, 169 m.

Met Met Office explanation of Heathrow record
 

"Scott W" wrote in message
...
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

Yep some proper and good science in there! Having said that it does not
prove that in strong insolation that there is not some effect from the
tarmac, but there is nothing that can be done about that, it is what it is -
a one day wonder very hot spell. Time to move on.

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

Met Met Office explanation of Heathrow record
 

On Tuesday, July 7, 2015 at 4:43:14 PM UTC+1, wrote:
"Scott W" wrote in message
...
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

Yep some proper and good science in there! Having said that it does not
prove that in strong insolation that there is not some effect from the
tarmac, but there is nothing that can be done about that, it is what it is -
a one day wonder very hot spell. Time to move on.

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

What it shows is that the Heathrow figure increased in tandem with many other areas. It really is an excellent, detailed and informative explanation from the MetO. More of them please.

Met Met Office explanation of Heathrow record
 

it is what it is - a one day wonder very hot spell. Time to move on.

Will
---------------------------------------------------
I guess any record daily temperature will be a "one day wonder" !
For what it's worth, there were some still notable maxima around that
week he-
June 29 - 27.4
June 30- 28.3
July 1 - 33.0
July 2 - 27.7
July 4 - 28.6

Dave

Met Met Office explanation of Heathrow record
 

"Eskimo Will" wrote in message ...

...it is what it is - a one day wonder very hot spell.

Actually from the instrumental record it seems to have been a 1-2-minute
wonder. It's a shame that the Met Office blog didn't provide a little more
detail, eg was this an aspirated screen or not (I'm guessing not given how
closely the temperature seems to have paralleled the insolation, but maybe
I'm wrong)? And what was the wind speed data at around Tx - it has the look
of screen heating under calm conditions. None of this invalidates the record
of course since it was made under standard conditions, but it would provide
some extra context.

Met Met Office explanation of Heathrow record
 

On Tuesday, July 7, 2015 at 8:18:49 PM UTC+1, JohnD wrote:
"Eskimo Will" wrote in.me...

...it is what it is - a one day wonder very hot spell.

Actually from the instrumental record it seems to have been a 1-2-minute
wonder. It's a shame that the Met Office blog didn't provide a little more
detail, eg was this an aspirated screen or not (I'm guessing not given how
closely the temperature seems to have paralleled the insolation, but maybe
I'm wrong)? And what was the wind speed data at around Tx - it has the look
of screen heating under calm conditions. None of this invalidates the record
of course since it was made under standard conditions, but it would provide
some extra context.
---------------------------------------------------------------------------
Exactly John, we need to see photos of the site and screen.
Plans and maps of its location with respect to the runways, taxi ways, terminal buildings and car parks.
Are they claiming the thermal properties of the surroundings had no effect?

Interesting to compare the readings to Kew, but an incomplete study in my book.

Would only give a student of mine 6 out of 10 for that.

Len
Wembury, SW Devon

---------------------------------------------------------------------------

Met Met Office explanation of Heathrow record
 

On Tue, 7 Jul 2015 07:36:11 -0700 (PDT), Tudor Hughes
wrote:

On Tuesday, 7 July 2015 15:01:29 UTC+1, Scott W wrote:
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

A good explanation. I didn't think so many local records had been broken and over so wide an area, though it didn't break mine (32 yrs). My max was 33.8°C but 19 July 2006 had 35.0°C.
It seems to me that a large majority of the public are suspicious of Heathrow readings ("all that tarmac, all those engines") but without justification.

Having read the explanation, and noted that very brief peak during a
short period of strong sunshine, and the 1 deg C excess over Kew
Gardens, my suspicions remain.

Increased urbanization and industrial development at many major
airports are IMO a real problem these days and it's long overdue for
the Met Office to conduct studies of these effects at such places.

Heck, I was suspicious of big airports near urban areas way back in
the 1970s when I did an analysis of increasing night minima at
Manchester Airport and persuaded the Met Office to conduct a study of
it. Their conclusion was what I had suspected, increased urbanization
to the north was forcing up the minima in northerlies, though not much
was said about runways and tarmac - probably because there was a lot
less of it back then. Heathrow synop station really needs to go west
a bit IMO, way beyond the airport perimeter as at Manchester now
(Rostherne no. 2) and Gatwick (Charlwood).

I think these factors are sometimes skewing the record at the
Heathrows of this World, though perhaps modern fast-reacting
thermometer probes are also a factor? I wonder what the mercury
thermometer recorded? If there is one, of course. And is the screen
wooden or plastic, aspirated, where is it sited, what were the wind
speeds and from which direction, all this is missing from the Met
Office's not-very-detailed analysis of the Heathrow record.

Unimpressed of Fareham.

--
Dave

Met Met Office explanation of Heathrow record
 

On Wednesday, 8 July 2015 01:25:05 UTC+1, Dave Ludlow wrote:
On Tue, 7 Jul 2015 07:36:11 -0700 (PDT), Tudor Hughes
wrote:

On Tuesday, 7 July 2015 15:01:29 UTC+1, Scott W wrote:
Puts to bed my criticisms from last week

http://blog.metoffice.gov.uk/2015/07...ng-a-heatwave/

A good explanation. I didn't think so many local records had been broken and over so wide an area, though it didn't break mine (32 yrs). My max was 33.8°C but 19 July 2006 had 35.0°C.
It seems to me that a large majority of the public are suspicious of Heathrow readings ("all that tarmac, all those engines") but without justification.

Having read the explanation, and noted that very brief peak during a
short period of strong sunshine, and the 1 deg C excess over Kew
Gardens, my suspicions remain.

Increased urbanization and industrial development at many major
airports are IMO a real problem these days and it's long overdue for
the Met Office to conduct studies of these effects at such places.

Heck, I was suspicious of big airports near urban areas way back in
the 1970s when I did an analysis of increasing night minima at
Manchester Airport and persuaded the Met Office to conduct a study of
it. Their conclusion was what I had suspected, increased urbanization
to the north was forcing up the minima in northerlies, though not much
was said about runways and tarmac - probably because there was a lot
less of it back then. Heathrow synop station really needs to go west
a bit IMO, way beyond the airport perimeter as at Manchester now
(Rostherne no. 2) and Gatwick (Charlwood).

I think these factors are sometimes skewing the record at the
Heathrows of this World, though perhaps modern fast-reacting
thermometer probes are also a factor? I wonder what the mercury
thermometer recorded? If there is one, of course. And is the screen
wooden or plastic, aspirated, where is it sited, what were the wind
speeds and from which direction, all this is missing from the Met
Office's not-very-detailed analysis of the Heathrow record.

Unimpressed of Fareham.

--
Dave

Aren't the modern thermometer probes electronically damped so as to have the same reaction times as mercury thermometers? There was an article about it in "Weather" some time ago. The solutions mentioned seemed to me at the time to be unnecessarily hi-tech - why not just enclose the probe in a specified sized blob of some material?

The effect of urbanisation is always much greater on minimum temperatures (especially in summer) than on max's. One could even plausibly argue that urban max's should be lower than rural ones because urban fabric is a better conductor of heat, more material is warmed and it has therefore a greater heat capacity. It lets it out at night. All this, however, ignores evapotranspiration which will be nil over concrete, tarmac etc. Maybe we should worry more about Heathrow minima though I don't actually know if they are regarded as "high". They will have the same effect on the mean temperature as excessive max's but far fewer people would notice and I doubt if we'd be talking about it.

Tudor Hughes, Warlingham, Surrey.