Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Historical Trends in 30-year CET averages


Roger J Smith

Recommended Posts

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

This is an effort to display the historical trends in CET values from 1659 to present in a graphical format. I have calculated mean monthly values for successive 30-year intervals, not quite the ones we are used to seeing, but those defined by the data set. Our current 30-year interval is 1989 to 2018 and this is of course not quite finished, but it does correspond very well to the period often cited as being the modern warming (certainly for winter means). The graphical nature of this presentation is achieved by placing the months in ascending order of mean temperature rather than chronological order, and by indenting the values at a scaled amount depending on changes from period to period.

INTERVAL_JAN_FEB__DEC___MAR___NOV____APR____OCT___ MAY____SEP____JUN___ AUG_JUL

1659-88 ___ 2.9 3.0 _ 3.4 ____ 4.8 ___ 5.7 _____ 7.4 ______ 9.6 __ 11.0 _____ 12.8 ___ 14.3 __ 15.3 _ 15.8

1689-18 __ 2.5 _ 3,3 __3.8 ___4.7 ____ 5.8 _____7.4 _____9.1 ___ 10.6 ______12.8 __13.9 ___15.4_15.7

1719-48 ______ 3.3 __ 3.8 _ 4.2 __ 5.0 ____ 6.4 __ 7.8 ____ 9.6 ____ 11.4 __________ 14.0_14.6 ____ 15.9 16.0

1749-78 __ 2.6 ___ 3.7 _ 4.0 ______ 5.3_5.6 _____ 7.9 ____9.3 ____ 11.2 ________ 13.4 __ 14.4 ____15.7 _ 16.1

1779-08 ___ 2.8_3.2__ 3.9 _____4.8_5.3 _________ 8.0 ___9.4 ______ 11.6 ______ 13.4 __ 14.5 ______16.0.16.2

1809-38 _2.2 __________44.11 _____ 5.5 _ 6.0 ___7.8 ______ 9.9 ___ 11.4 _____ 13.1 ___ 14.4 __15.2__15.8

1839-68 _______ 3.3 _ 3.8 __ 4.4 __ 5.1 _ 5.7 _____ 8.1 ___ 9.5 ____ 11.2 ______ 13.1 ___ 14.4 __ 15.3_15.6

1869-98 _______3.4 3.5__ 4.2 ____ 5.2 __ 6.0 ____ 8.0 _ 9.0 _____ 10.7 ________ 13.2 __ 14.2 ___ 15.4 _ 15.8

1899-28 _____________ 4.34.44.5 __ 5.5_5.9 ___ 7.7 _____ 9.7 ____ 11.3 _____ 13.0 __ 13.9 ____ 15.3 __ 15.9

1929-58 _______ 3.5 3.7 ___ 4.7 _____ 5.8 __ 6.7 __ 8.4 ____ 10.0 __ 11.3 __________ 13.8 _ 14.5 ______ 16.0_16.2

1959-88 ______ 33.66 _____4.7 _____5.6 __ 6.6 __ 8.0 _______ 10.6_11.2 _________ 13.6 __ 14.3 ___ 15.7_16.0

1989-16 ______________ 4.789 _________ 6.8 _ 7.4 ___ 8.7 ___ 11.0 _ 11.9 _________ 14.1 _ 14.5 ________ 16.5_16.8

_____________________________________________________________________________________

Note, DEC, NOV and SEP are in bold to assist in folllowing the trends. December changes place with February as second coldest month for the 1779-1808 interval and returns to that location for 1869-1898 and for the most recent period 1989-2016. There were no other cases where months changed order, September 1719-1748 warmed up considerably but failed to overtake June. July has always edged out August as warmest. However, a more detailed analysis for every 30-year interval shows that February was coldest for intervals centred on 1965-94 when Feb was 0.3 colder than January.

I may post further on this topic once I have a chance to look over the detailed analysis.

Edited by Roger J Smith
  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

A more familiar 30-year interval historical record follows:

INTERVAL _ JAN_FEB_MAR_APR_MAY_JUN_JUL_AUG_SEP_OCT_NOV_DEC

1661-90 ____ 2.9 _ 3.1 _ 4.8 _ 7.4 _11.0 _14.3 _15.8 _15.3 _12.8 _ 9.5 _ 5.7 _ 3.4

1691-1720 __ 2.6 _ 3.3 _ 4.7 _ 7.4 _10.7 _14.0 _15.8 _15.5 _12.9 _ 9.1 _ 5.8 _ 3.8

1721-50 ____ 3.4 _ 3.9 _ 5.2 _ 7.8 _11.4 _14.5 _16.0 _15.9 _14.0 _ 9.6 _ 6.3 _ 4.2

1751-80 ____ 2.4 _ 3.7 _ 5.3 _ 7.9 _11.2 _14.5 _16.1 _15.8 _13.4 _ 9.3 _ 5.6 _ 3.9

1781-1810 __ 2.9 _ 3.9 _ 4.6 _ 8.0 _11.5 _14.5 _16.1 _15.8 _13.2 _ 9.4 _ 5.3 _ 3.2

1811-40 ____ 2.3 _ 4.1 _ 5.4 _ 7.9 _11.4 _14.4 _15.7 _15.2 _13.0 _ 9.8 _ 6.1 _ 4.0

1841-70 ____ 3.4 _ 3.9 _ 5.2 _ 8.2 _11.2 _14.4 _15.8 _15.4 _13.2 _ 9.6 _ 5.7 _ 4.3

1871-1900 __ 3.4 _ 4.1 _ 5.2 _ 7.9 _10.7 _14.2 _15.8 _15.5 _13.1 _ 9.0 _ 6.1 _ 3.7

1901-30 ____ 4.2 _ 4.2 _ 5.5 _ 7.6 _11.3 _13.8 _15.8 _15.2 _13.1 _ 9.8 _ 5.8 _ 4.5

1931-60 ____ 3.5 _ 3.9 _ 5.9 _ 8.5 _11.4 _14.6 _16.2 _16.0 _13.7 _10.1 _ 6.8 _ 4.7

1961-90 ____ 3.8 _ 3.8 _ 5.7 _ 7.9 _11.2 _14.2 _16.1 _15.8 _13.6 _10.6 _ 6.6 _ 4.7

1971-2000 __ 4.2 _ 4.2 _ 6.3 _ 8.1 _11.3 _14.1 _16.5 _16.2 _13.7 _10.4 _ 6.9 _ 5.1

1981-2010 __ 4.4 _ 4.4 _ 6.6 _ 8.5 _11.7 _14.5 _16.7 _16.4 _14.0 _10.7 _ 7.1 _ 4.6

1986-2015 __ 4.6 _ 4.6 _ 6.6 _ 8.7 _11.8 _14.5 _16.6 _16.4 _14.0 _10.9 _ 7.3 _ 5.0

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

December was second coldest of the months continuously in terms of 30-year average values from 1761-90 to 1811-40 and at times was 1.0 C colder than February in that period (the biggest deficit was around 1790-1819).

After a few decades of being milder than February, December resumed second place in the 1848-77 interval and stayed in that position until 1880-1909; around 1851-80 it was about 0.7 C colder than February for about 25 consecutive 30-year intervals (on an annual basis). During this time it came close to being as cold as January (the closest was about 0.2 deg in 1868-97).

February became the coldest month (in 30-year intervals) in 1946-75 and held on to that role for just two intervals (including 1947-76) and returned to being the coldest for two more (1954-83, 1955-84) and also 1957-86. The two months have moved pretty much in lock-step since those closer intervals with February colder by 0.1-0.2 from 1960-89 to 1970-99. January then resumed its role as coldest month until recent intervals except for marginal cases 1981-2010 and 1983-2012. December has been third coldest all through this interval despite the impact of December 2010 which has placed the last few intervals considerably closer to January and February.

The closest that March got to being third coldest was 1863-92 when March averaged 4.9 and February 4.4.

The closest that November came to moving out of fifth into fourth was 1851-80 when November averaged 5.33 and March 5.24 -- the difference most of the time is closer to one degree.

The warmest 30-year interval is usually the most recent one available. This is true for Jan (1987-2016) 4.63; Feb 4.85; March 6.68; April 8.78; May 11.82; Oct (both 1985-2014 and 1986-2015) 10.93; Nov 7.32 (also 1986-2915),

For July, the warmest 30-year interval was 1981-2010 (16.71). For August it was 1975-2004 (16.46). In September the warmest was 14.06 (both 1978-2007 and 1980-2009) which was almost matched 1985-2014. However, back in 1721-50 September peaked at 14.0, which it did not achieve again until 1977-2006.

The warmest December 30-year interval was 1971-2000 (5.06). Last December returned the value to 4.97 after somewhat lower averages driven by the very cold 2010. If this coming December hits 9.7 again we will see a new peak of 5.09.

June is certainly the exception to all of these rules. The peak 30-year interval for June was 14.72 in 1822-51. This edged out the 14.70 set in 1772-1801. The warmest value in recent years was only 14.50 (1987-2016 and 1982-2011). All of the intervals starting in 1931-60 to 1941-70 ran a bit warmer than this modern value at about 14.51-57.

 

 

 

  • Like 4
Link to comment
Share on other sites

Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

Interesting stats, the period June-Sept bucking the trend from the rest of the year in terms of continuous warming. June very notable anomaly, sustained June warmth has been hard to come by over the past 20-30 years.

Link to comment
Share on other sites

  • 2 weeks later...
Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

Here are the complete 30-year averages in ten-year intervals, also including 1986-2015 at the end.

INTERVAL __ JAN_FEB_MAR_APR_MAY_JUN_JUL_AUG_SEP_OCT_NOV_DEC

1661-1690 __ 2.9 _ 3.1 _ 4.8 _ 7.4 _ 11.0 _ 14.3_15.8_15.3_12.8 _ 9.5 _ 5.7 _ 3.4

1671-1700 __ 2.6 _ 2.6 _ 4.4 _ 7.1 _ 10.7 _ 13.9_15.5_14.9_12.3 _ 9.0 _ 5.3 _ 3.3

1681-1710 __ 2.4 _ 3.0 _ 4.5 _ 7.3 _ 10.8 _ 13.9_15.6_15.3_12.6 _ 9.0 _ 5.6 _ 4.0

1691-1720 __ 2.6 _ 3.3 _ 4.7 _ 7.4 _ 10.7 _ 14.0_15.8_15.5_12.9 _ 9.1 _ 5.8 _ 3.8

1701-1730 __ 3.1 _ 3.8 _ 5.1 _ 7.9 _ 11.3 _ 14.4_15.9_15.8_13.6 _ 9.5 _ 6.4 _ 4.0

1711-1740 __ 3.4 _ 4.0 _ 5.4 _ 8.1 _ 11.2 _ 14.6_16.0_15.7_13.8 _ 9.7 _ 6.2 _ 4.1

1721-1750 __ 3.4 _ 3.9 _ 5.2 _ 7.8 _ 11.4 _ 14.5_16.0_15.9_14.0 _ 9.6 _ 6.3 _ 4.2

1731-1760 __ 3.3 _ 3.8 _ 5.3 _ 7.7 _ 11.2 _ 14.5_16.1_15.8_13.8 _ 9.4 _ 5.8 _ 4.2

1741-1770 __ 2.9 _ 3.7 _ 4.8 _ 7.6 _ 11.2 _ 14.3_16.0_15.7_13.6 _ 9.2 _ 5.7 _ 3.9

1751-1780 __ 2.4 _ 3.7 _ 5.3 _ 7.9 _ 11.2 _ 14.5_16.1_15.8_13.4 _ 9.3 _ 5.6 _ 4.0

1761-1790 __ 2.4 _ 3.7 _ 4.8 _ 7.9 _ 11.5 _ 14.6_16.1_15.8_13.3 _ 9.2 _ 5.5 _ 3.7

1771-1800 __ 2.4 _ 3.8 _ 4.9 _ 8.1 _ 11.4 _ 14.7_16.3_15.9_13.4 _ 9.4 _ 5.3 _ 3.3

1781-1810 __ 2.9 _ 3.9 _ 4.6 _ 8.0 _ 11.5 _ 14.5_16.1_15.8_13.2 _ 9.4 _ 5.3 _ 3.2

1791-1820 __ 2.5 _ 4.0 _ 5.1 _ 8.0 _ 11.2 _ 14.2_15.9_15.6_13.1 _ 9.5 _ 5.5 _ 3.2

1801-1830 __ 2.4 _ 4.0 _ 5.5 _ 7.9 _ 11.4 _ 14.2_15.8_15.4_13.1 _ 9.8 _ 5.9 _ 3.6

1811-1840 __ 2.3 _ 4.1 _ 5.4 _ 7.9 _ 11.4 _ 14.4_15.7_15.2_13.0 _ 9.8 _ 6.1 _ 4.0

1821-1850 __ 2.6 _ 3.9 _ 5.5 _ 8.0 _ 11.6 _ 14.7_15.7_15.3_13.0 _ 9.6 _ 6.3 _ 4.5

1831-1860 __ 3.2 _ 3.7 _ 5.2 _ 7.8 _ 11.2 _ 14.6_15.7_15.4_13.0 _ 9.6 _ 5.8 _ 4.3

1841-1870 __ 3.4 _ 3.9 _ 5.2 _ 8.2 _ 11.2 _ 14.4_15.8_15.4_13.2 _ 9.6 _ 5.7 _ 4.3

1851-1880 __ 3.7 _ 4.2 _ 5.2 _ 8.2 _ 10.8 _ 14.2_15.9_15.6_13.2 _ 9.7 _ 5.3 _ 4.1

1861-1890 __ 3.5 _ 4.5 _ 5.1 _ 8.1 _ 10.9 _ 14.1_15.8_15.4_13.2 _ 9.3 _ 5.7 _ 3.8

1871-1900 __ 3.4 _ 4.1 _ 5.2 _ 7.9 _ 10.7 _ 14.2_15.8_15.5_13.1 _ 9.0 _ 6.1 _ 3.7

1881-1910 __ 3.5 _ 3.9 _ 5.1 _ 7.7 _ 10.9 _ 14.1_15.7_15.2_13.1 _ 9.3 _ 6.3 _ 4.0

1891-1920 __ 3.7 _ 4.1 _ 5.3 _ 7.9 _ 11.3 _ 14.1_15.7_15.4_13.1 _ 9.4 _ 6.2 _ 4.5

1901-1930 __ 4.2 _ 4.2 _ 5.5 _ 7.6 _ 11.3 _ 13.8_15.8_15.2_13.1 _ 9.8 _ 5.8 _ 4.5

1911-1940 __ 4.2 _ 4.3 _ 5.7 _ 7.8 _ 11.5 _ 14.2_15.9_15.6_13.3 _ 9.6 _ 6.2 _ 4.6

1921-1950 __ 3.9 _ 4.2 _ 5.9 _ 8.3 _ 11.3 _ 14.4_16.3_15.9_13.6 _10.0_ 6.4 _ 4.5

1931-1960 __ 3.5 _ 3.9 _ 5.9 _ 8.5 _ 11.4 _ 14.6_16.2_16.0_13.7 _10.1_ 6.8 _ 4.7

1941-1970 __ 3.3 _ 3.6 _ 5.7 _ 8.5 _ 11.4 _ 14.5_16.0_15.7_13.7 _10.6_ 6.6 _ 4.4

1951-1980 __ 3.6 _ 3.7 _ 5.6 _ 8.0 _ 11.3 _ 14.3_15.9_15.6_13.6 _10.5_ 6.6 _ 4.7

1961-1990 __ 3.8 _ 3.8 _ 5.7 _ 7.9 _ 11.2 _ 14.2_16.1_15.8_13.6 _10.6_ 6.6 _ 4.7

1971-2000 __ 4.2 _ 4.2 _ 6.3 _ 8.1 _ 11.3 _ 14.1_16.5_16.2_13.7 _10.4_ 6.9 _ 5.1

1981-2010 __ 4.4 _ 4.4 _ 6.6 _ 8.5 _ 11.7 _ 14.5_16.7_16.4_14.0 _10.7_ 7.1 _ 4.6

1986-2015 __ 4.6 _ 4.6 _ 6.6 _ 8.7 _ 11.8 _ 14.5_16.6_16.4_14.0 _10.9_ 7.3 _ 5.0

(1987-2016)_ 4.6 _ 4.8 _ 6.7 _ 8.8 _ 11.8 _ 14.5

1659-2016*_ 3.3 _ 3.9 _ 5.3 _ 7.9 _ 11.2 _ 14.3_16.0_15.6_13.3 _ 9.7 _ 6.1 _ 4.1

* (1659-2015 July to Dec)

 

Edited by Roger J Smith
  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Yorkshire Puddin' aka Kirkham, Lancashire, England, United Kingdom
  • Weather Preferences: cold winters, cold springs, cold summers and cold autumns
  • Location: Yorkshire Puddin' aka Kirkham, Lancashire, England, United Kingdom

Its remarkable that despite ending with the coldest October on record, a very cold 5.3C in 1740, the 1711-1740 October average was the warmest until 1801-1830.

Edited by Lettucing Gutted
  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

As it turned out, 1740 took some of the steam out of even higher averages, 9.86 (rounded to 9.9) for 1699-1738 then 9.84 (rounded to 9.8) for 1700-1739. The average for 1701-40 was 9.70 exactly.

 

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-29 07:13:16 Valid: 29/03/2024 0600 - 30/03/2024 0600 THUNDERSTORM WATCH - FRI 29 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather

    Difficult travel conditions as the Easter break begins

    Low Nelson is throwing wind and rain at the UK before it impacts mainland Spain at Easter. Wild condtions in the English Channel, and more rain and lightning here on Thursday. Read the full update here

    Netweather forecasts
    Netweather forecasts
    Latest weather updates from Netweather

    UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-28 09:16:06 Valid: 28/03/2024 0800 - 29/03/2024 0600 SEVERE THUNDERSTORM WATCH - THURS 28 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather
×
×
  • Create New...