Sunshine Hours and the Central England Temperature Record
Jan 11, 2017 0:03:06 GMT
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Post by missouriboy on Jan 11, 2017 0:03:06 GMT
I will start this thread with a thread-relevant video tribute to a departed musical artist. www.youtube.com/watch?v=JcnNb7Pnmok
A Comparison of Sunshine Hours for England with the CET Temperature Record
Nautonnier suggested that sunshine hours might be a good reverse proxy for cloud cover. The Met has files on sunshine hours from 1929 to 2016 for major regions of the UK. I chose England as the best equivalent to the CET area which is defined as a rough triangle from London to Bristal to Lancashire and back. Seasonal aggregate sunshine hours are shown in Chart1 while chart 2, 3 and 4 compare Summer, spring and winter sunshine hours to the CET record.
Each season has slightly different trends. Summer 5-year sunshine hour trends peak in 1995 and have declined since. Spring shows declines in the colder period from 1960 to 1988 followed by an increase through 2010 and a decline since. Fall and winter show marginal long-term increases through 2006 and 2002 respectively and declines since. These trends are generally consistent with CET trends.
Seasonal Sunshine and the CET
Summer sunshine hour trends are amazingly coincident with the summer CET record. The greatest discrepancy occurs from 1996 to 2010 when temperature changes outpaced sunshine hours. Could be the large AMO increase in this period or something else ... or, could it be vermin???
Spring shows similar discrepancies from the CET in the 1990-2010 period. Winter trends in both variables are upward. So, with the exception of the 1990-2010 period, cloudier periods are also colder periods, while in winter, cloudier are often (but not always) warmer. Of course we knew that.
There appears to be no doubt that England has been getting colder and cloudier in recent years.
A Comparison of Sunshine Hours for England with the CET Temperature Record
Nautonnier suggested that sunshine hours might be a good reverse proxy for cloud cover. The Met has files on sunshine hours from 1929 to 2016 for major regions of the UK. I chose England as the best equivalent to the CET area which is defined as a rough triangle from London to Bristal to Lancashire and back. Seasonal aggregate sunshine hours are shown in Chart1 while chart 2, 3 and 4 compare Summer, spring and winter sunshine hours to the CET record.
Each season has slightly different trends. Summer 5-year sunshine hour trends peak in 1995 and have declined since. Spring shows declines in the colder period from 1960 to 1988 followed by an increase through 2010 and a decline since. Fall and winter show marginal long-term increases through 2006 and 2002 respectively and declines since. These trends are generally consistent with CET trends.
Seasonal Sunshine and the CET
Summer sunshine hour trends are amazingly coincident with the summer CET record. The greatest discrepancy occurs from 1996 to 2010 when temperature changes outpaced sunshine hours. Could be the large AMO increase in this period or something else ... or, could it be vermin???
Spring shows similar discrepancies from the CET in the 1990-2010 period. Winter trends in both variables are upward. So, with the exception of the 1990-2010 period, cloudier periods are also colder periods, while in winter, cloudier are often (but not always) warmer. Of course we knew that.
There appears to be no doubt that England has been getting colder and cloudier in recent years.