Welcome Guest! To enable all features please Login. New Registrations are disabled.

Notification

Icon
Error

13 Pages«<111213
Options
Go to last post Go to first unread
Online KevBrads1  
#241 Posted : 02 January 2016 11:04:53(UTC)
KevBrads1

Rank: Advanced Member

Joined: 17/03/2012(UTC)
Posts: 28,482
Location: Irlam

What December 2015 was the meteorological equivalent of what Bob Beamon did at Mexico in 1968.

Maybe we should nickname December 2015, Bob Beamon, it certainly did a Bob Beamon!


Timelapses, old weather forecasts and natural phenomena videos can be seen on this site
http://www.youtube.com/c...z2feWDTydhpEhQ/playlists
Offline Global Warming  
#242 Posted : 02 January 2016 11:14:06(UTC)
Global Warming

Rank: Advanced Member

Joined: 07/10/2006(UTC)
Posts: 6,108

A few additional stats on 2015


Lowest CET mean of the year: -0.3C on 2 Feb. This was the only negative CET mean in 2015.


There were two reasonably cool spells early in the year:


CET mean from 17 to 24 Jan was just 1.2C. The highest mean in that period was 2.5C


CET mean from 2 to 7 Feb was just 1.3C. The highest mean in that period was 2.3C


Highest CET mean of the year was 24.6C on 1 July.


Only two other days went over 20C and they were 30 June with 20.2C and 22 August with 20.1C


In November and December a total of 33 days had a CET mean of more than 10C. Only 4 days had a CET mean of less than 5C (21 - 24 Nov).

Chineham, Basingstoke, Hampshire, 86m asl
Offline Global Warming  
#243 Posted : 02 January 2016 11:30:16(UTC)
Global Warming

Rank: Advanced Member

Joined: 07/10/2006(UTC)
Posts: 6,108

Originally Posted by: Devonian Go to Quoted Post


Not sure if this has been discussed but how does this December compare in a standard deviation kind of way to other record months? Or, I think I'm asking, how record is it?


I guess another way of looking at it is that a tm airstream persisted for much of the month. A tm airstream perhaps a degree warmer than we might expect? Or brought to us more directly from the far SW than is usual? We didn't smash maxima much we smashed persistence of airmass?


It's interesting reading other observation as that few other months could do this since we'd expect less cloud, the odd clear night, some cold night, in other months. I guess we might, next EN, see a November the same, one that averaged 11C now seem possible, or October and 14C plus. But, not later winter or spring months I guess.



I have had a look back to see if I can find other instances where the existing CET record for a month was broken by more than 1C. I have only considered dates after there was already at least 100 years in the data series (i.e. 1760 onwards). I found one:


May 1833 saw a CET of 15.1C. The previous record was 13.8C set in 1758 and 1788. So an increase of 1.3C on the existing record.


Not quite as much of an increase in the record as December 2015 but close. At that point there were almost 200 data points in the series. In December 2015 there were over 350 data points and the movement in the record was greater. So December 2015 is unprecedented and there seems to be only one other instance in the whole of the CET data set that comes close.


Incidentally that May CET figure of 15.1C from 1833 still stands. Since then the highest May CET was 13.9C in 1848. In recent times the warmest May was 13.6C 1992 and 13.4C in 2008. There has never been a May CET in the 14's at all. So that 15.1C figure in 1833 was truly exceptional and does merit being up there with the December 2015 figure I think.

Edited by user 02 January 2016 11:31:44(UTC)  | Reason: Not specified

Chineham, Basingstoke, Hampshire, 86m asl
Offline ARTzeman  
#244 Posted : 02 January 2016 12:33:57(UTC)
ARTzeman

Rank: Advanced Member

Joined: 14/07/2012(UTC)
Posts: 25,591
Man
Location: Peasedown St John. N.E. Sommerset

Thanks for the charts and figures along with running the Watch....  Must look at December properly later today. 


Well done to Lanky for being " Top Man" ......     


Nice to see new names.......



Some people walk in the rain.
Others just get wet.
Offline Hungry Tiger  
#245 Posted : 02 January 2016 16:54:35(UTC)
Hungry Tiger

Rank: Advanced Member

Joined: 11/04/2006(UTC)
Posts: 24,716
Location: South Cambridgeshire

Originally Posted by: Gavin P Go to Quoted Post


And what to say about December 2015 other than....  



Exactly - I am tempted to suggest that this December has been on a par with one of the most remarkable weather events of the past 100 years or so like the summer of 1976 and the winter of 1963.


I have never known a month like this December to break records like this one did.


 

Gavin S.

UserPostedImage

Contact the TWO team - twomoderationteam@gmail.com

South Cambridgeshire. 93metres asl.


Offline Hungry Tiger  
#246 Posted : 02 January 2016 16:55:32(UTC)
Hungry Tiger

Rank: Advanced Member

Joined: 11/04/2006(UTC)
Posts: 24,716
Location: South Cambridgeshire

I'll keep this stickied for at least another week so we can see all these amazing records. Make sure everyone has had time to read and digest this.


 

Gavin S.

UserPostedImage

Contact the TWO team - twomoderationteam@gmail.com

South Cambridgeshire. 93metres asl.


Offline springsunshine  
#247 Posted : 02 January 2016 17:27:59(UTC)
springsunshine

Rank: Advanced Member

Joined: 14/11/2011(UTC)
Posts: 1,156
Location: Bournemouth

Originally Posted by: Hungry Tiger Go to Quoted Post


 


Exactly - I am tempted to suggest that this December has been on a par with one of the most remarkable weather events of the past 100 years or so like the summer of 1976 and the winter of 1963.


I have never known a month like this December to break records like this one did.


 



In all probability the events above are more like 1 in 1000 year events and its what makes the british climate so special and exciting you just never know what is going to happen unlike many places around the globe.

Offline Caz  
#248 Posted : 02 January 2016 22:09:41(UTC)
Caz

Rank: Advanced Member

Joined: 28/10/2008(UTC)
Posts: 18,098
Woman
Location: Market Warsop, Nottinghamshire, East Midlands

Originally Posted by: Hungry Tiger Go to Quoted Post


I'll keep this stickied for at least another week so we can see all these amazing records. Make sure everyone has had time to read and digest this.


Would it be possible to have an archive of the CET competitions? 


I'd find it useful to look back on these threads as I often wonder how previous months performed, especially the ones that throw up record breakers like December did and I'd also like to see how I performed in previous months.  Apart from that, some of our members take the time and effort to post some very useful stats.  So it would be nice if we could keep them all because it's a shame when these threads drop off the radar and disappear for ever and I'm sure other members would agree.


Thanks in advance and anticipation! 

Market Warsop, North Nottinghamshire.
Join the fun of the monthly CET competition. Last chance to join in the yearly comp is 2nd March. Discuss monthly temperatures and records.
Offline Hungry Tiger  
#249 Posted : 03 January 2016 12:19:34(UTC)
Hungry Tiger

Rank: Advanced Member

Joined: 11/04/2006(UTC)
Posts: 24,716
Location: South Cambridgeshire

Originally Posted by: Caz Go to Quoted Post


Would it be possible to have an archive of the CET competitions? 


I'd find it useful to look back on these threads as I often wonder how previous months performed, especially the ones that throw up record breakers like December did and I'd also like to see how I performed in previous months.  Apart from that, some of our members take the time and effort to post some very useful stats.  So it would be nice if we could keep them all because it's a shame when these threads drop off the radar and disappear for ever and I'm sure other members would agree.


Thanks in advance and anticipation! 



I'll pas this on to the admin team :-)


I am sure we can work out something. There is some sort of archive system - but its a bit complex.


 

Gavin S.

UserPostedImage

Contact the TWO team - twomoderationteam@gmail.com

South Cambridgeshire. 93metres asl.


Offline Caz  
#250 Posted : 03 January 2016 19:45:50(UTC)
Caz

Rank: Advanced Member

Joined: 28/10/2008(UTC)
Posts: 18,098
Woman
Location: Market Warsop, Nottinghamshire, East Midlands

Originally Posted by: Hungry Tiger Go to Quoted Post


I'll pas this on to the admin team :-)


I am sure we can work out something. There is some sort of archive system - but its a bit complex.


  Thanks.    I think it's worth a try.

Market Warsop, North Nottinghamshire.
Join the fun of the monthly CET competition. Last chance to join in the yearly comp is 2nd March. Discuss monthly temperatures and records.
Offline lanky  
#251 Posted : 03 January 2016 21:54:35(UTC)
lanky

Rank: Advanced Member

Joined: 05/04/2006(UTC)
Posts: 3,464
Man

I was intrigued as to whether the exceptionally mild December could have beaten in terms of the anomaly if any 30 day period was included rather than just the days spanning a calendar month.


In order to find out the daily CET records are required to be analysed rather than the monthly averages.


Fortunately daily CET means exist from 1772 up to the current day and so a sample of 244 years (about 89000 days) is available for analysis rather than the 357 years of monthly data


It turns out that December 2015 was SO exceptional that no 30 period chosen can beat the monthly recods set last week


My list of results is shown below for both hot and cold records covering every 30 day period on the file



The cold records are far more extreme than the hot records mostly reflecting the occasional very severe winters we get with a blocking northern high


(for those interested the daily CET data was "detrended" by gradually increasing the temperature of older data to reflect the overall gradual warming in the last 250 years. This detrending totalled just under 1C applied across the whole data incrementally. Anomalies were calculated based on the average temperature for that day in the year)


I also had a go at calculating the "return period" for such an exceptional month using statistical analysis. Because the data is highly skewed towards colder temperatures at the extreme ends it is not easy. To get a 30 day anomaly that fits exactly into 1 calendar month is itself a 1 in 30 chance and to allow for this and the relative rarity of extreme warm periods I got  a return period of 1850 years - although I'm not convinced about this


 


 


 


 

SHOW EXTERNAL IMAGES

Martin
Richmond, Surrey
Offline Devonian  
#252 Posted : 03 January 2016 22:19:03(UTC)
Devonian

Rank: Advanced Member

Joined: 02/05/2006(UTC)
Posts: 26,859
Man
Location: East Dartmoor

Originally Posted by: lanky Go to Quoted Post


I was intrigued as to whether the exceptionally mild December could have beaten in terms of the anomaly if any 30 day period was included rather than just the days spanning a calendar month.


In order to find out the daily CET records are required to be analysed rather than the monthly averages.


Fortunately daily CET means exist from 1772 up to the current day and so a sample of 244 years (about 89000 days) is available for analysis rather than the 357 years of monthly data


It turns out that December 2015 was SO exceptional that no 30 period chosen can beat the monthly recods set last week


My list of results is shown below for both hot and cold records covering every 30 day period on the file



The cold records are far more extreme than the hot records mostly reflecting the occasional very severe winters we get with a blocking northern high


(for those interested the daily CET data was "detrended" by gradually increasing the temperature of older data to reflect the overall gradual warming in the last 250 years. This detrending totalled just under 1C applied across the whole data incrementally. Anomalies were calculated based on the average temperature for that day in the year)


I also had a go at calculating the "return period" for such an exceptional month using statistical analysis. Because the data is highly skewed towards colder temperatures at the extreme ends it is not easy. To get a 30 day anomaly that fits exactly into 1 calendar month is itself a 1 in 30 chance and to allow for this and the relative rarity of extreme warm periods I got  a return period of 1850 years - although I'm not convinced about this


 


 


 


 



.


Why detrend the data? Or, in what way does the undetrended data result differ I guess I'm asking?


I see Tamino has done a similar analysis, though just limited to calendar months - unsurprisingly, the same result.


Interesting 74/5 is in there - very similar by my recollection, if less tm dominated in December. But a little surprising that a 30 day spell in 76 didn't beat it - many days must have had maxima well past 5C above normal, cooler nights maybe. Indeed, I just wonder how high the minima anomaly for December was, I bet it's here somewhere....

SHOW EXTERNAL IMAGES

Edited by user 03 January 2016 22:21:48(UTC)  | Reason: Not specified

"In a 52-48 referendum this would be unfinished business by a long way"
Nigel Farage, Daily Mirror, 16/5/2016
"I think the mistake the government made - led by Theresa May - from the start was to try and claim that a country that had voted 17 million to leave the EU, 16 million to stay, wanted a 100% Brexit"
Osborne, 22/12/18.
Offline wallaw  
#253 Posted : 04 January 2016 08:34:45(UTC)
wallaw

Rank: Advanced Member

Joined: 07/04/2006(UTC)
Posts: 12,091
Man
Location: Stockton-on-Tees

Many thanks for all your efforts throughout the year. Despite my dismal effort this year I love doing this and will continue to do so for as long as you are running the comp.


Happy new year

Ian


Stockton-on-Tees

Offline lanky  
#254 Posted : 04 January 2016 09:43:52(UTC)
lanky

Rank: Advanced Member

Joined: 05/04/2006(UTC)
Posts: 3,464
Man

Originally Posted by: Devonian Go to Quoted Post


 


.


Why detrend the data? Or, in what way does the undetrended data result differ I guess I'm asking?


I see Tamino has done a similar analysis, though just limited to calendar months - unsurprisingly, the same result.


Interesting 74/5 is in there - very similar by my recollection, if less tm dominated in December. But a little surprising that a 30 day spell in 76 didn't beat it - many days must have had maxima well past 5C above normal, cooler nights maybe. Indeed, I just wonder how high the minima anomaly for December was, I bet it's here somewhere....



Dev:


I Just detrended to get to a "level playing field". The early data was at the end of the LIA so getting a 30C day then was more impressive than today and similarly colder winters in the 18th and 19th century were more prevalent. The adjustment on the oldest data was about +0.95C gradually reducing to zero on current data.


The average adjustment was therefore about 0.48C so without this detrending but still using date averages across the whole file, you would subtract about 0.5C from the oldest anomalies (e.g. 1779) and add 0.5C to the newest (e.g 2015).  I don't think this is such a fair comparison and would show December 2015 as even more remarkable


As for summer 1976, I just had a look and the main blast of the real hot weather was 23/06 up to 09/07 so a lot less than 30 days. The remaining days up to the end of July were more moderate and this reduced the overall average somewhat


 

Martin
Richmond, Surrey
Offline Saint Snow  
#255 Posted : 04 January 2016 09:57:14(UTC)
Saint Snow

Rank: Advanced Member

Joined: 05/04/2006(UTC)
Posts: 42,833
Man
Location: St Helens

Many thanks for all the work you put into this, GW - we all really appreciate it.

Trump on Jeffrey Epstein:
"I’ve known Jeff for fifteen years. Terrific guy. He’s a lot of fun to be with. It is even said that he likes beautiful women as much as I do, and many of them are on the younger side. No doubt about it — Jeffrey enjoys his social life."

Martin
Home: St Helens (26m asl) Work: Manchester (75m asl)
A TWO addict since 14/12/01
Offline Twister  
#256 Posted : 04 January 2016 12:10:46(UTC)
Twister

Rank: Advanced Member

Joined: 05/04/2006(UTC)
Posts: 4,148
Man
Location: Egerton, Kent 33mASL

Brilliant competition - thanks GW for your work on this!

And nice to creep up 8 places into the top 40 for the first time since March. Yes, my performance has been that bad...
Location: Egerton, Kent - 33m ASL
Thunder 2016: 12 (Apr 3,13; May 21; Jun 8,11,17,22,23,25, Jul 2,12, Aug 26)
Winter 2015/6: Snowfalls: 10 | Snowcover: 2 (Jan 17 (0.5cm)) | Air frosts: 39
Winter 2016/7: Snowfalls: 4 (Jan 12-3, Feb 10-11) | Snowcover: 2 (Jan 13, 2cm, Feb 11, 3-5mm) | Air frosts: 57 (2 in Oct, 10 in Nov, 13 in Dec, 19 in Jan, 6 in Feb, 3 in Mar, 4 in Apr)
"The heavens tell of the glory of God. The skies display his marvellous craftsmanship." (Psalm 19:1)
Offline Sussex snow magnet  
#257 Posted : 04 January 2016 13:00:06(UTC)
Sussex snow magnet

Rank: Advanced Member

Joined: 05/12/2010(UTC)
Posts: 163
Man
Location: Sussex

Originally Posted by: lanky Go to Quoted Post


I was intrigued as to whether the exceptionally mild December could have beaten in terms of the anomaly if any 30 day period was included rather than just the days spanning a calendar month.


In order to find out the daily CET records are required to be analysed rather than the monthly averages.


Fortunately daily CET means exist from 1772 up to the current day and so a sample of 244 years (about 89000 days) is available for analysis rather than the 357 years of monthly data


It turns out that December 2015 was SO exceptional that no 30 period chosen can beat the monthly recods set last week


My list of results is shown below for both hot and cold records covering every 30 day period on the file



The cold records are far more extreme than the hot records mostly reflecting the occasional very severe winters we get with a blocking northern high


(for those interested the daily CET data was "detrended" by gradually increasing the temperature of older data to reflect the overall gradual warming in the last 250 years. This detrending totalled just under 1C applied across the whole data incrementally. Anomalies were calculated based on the average temperature for that day in the year)


I also had a go at calculating the "return period" for such an exceptional month using statistical analysis. Because the data is highly skewed towards colder temperatures at the extreme ends it is not easy. To get a 30 day anomaly that fits exactly into 1 calendar month is itself a 1 in 30 chance and to allow for this and the relative rarity of extreme warm periods I got  a return period of 1850 years - although I'm not convinced about this


 


 


 


 



Excellent post Lanky and just goes to show how exteme December was, but also highlights how few 30 day periods in recent times have been exteme regards anomoly.


A different question for you or Gw how far back or forth from december do you have to go to find a higher 30 period in actual cet as opposed to an annomaly difference.


 

SHOW EXTERNAL IMAGES

Users browsing this topic
Similar Topics
December CET watch (Weather)
by Global Warming 28/11/2017 22:27:35(UTC)
December CET watch (Weather)
by Global Warming 28/11/2016 23:06:49(UTC)
December CET watch (Weather)
by Global Warming 27/11/2014 22:31:02(UTC)
December CET watch (Weather)
by Global Warming 28/11/2013 22:44:26(UTC)
December CET watch (Weather)
by Global Warming 26/11/2012 22:44:51(UTC)
December CET watch (Weather)
by Global Warming 25/11/2011 22:48:31(UTC)
December CET watch (Weather)
by Hungry Tiger 20/11/2010 14:43:18(UTC)
13 Pages«<111213
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Code of conduct

× USER PHOTOS Sky Eye Camera Sky Eye Live Sky Eye Gallery MODEL CHARTS Arome Arpege ECM ECM ENS GEM GEFS GFS HIRLAM Icon Met Office UM Fax CFS GFSP