Brian Gunter, Narooma, NSW, Australia

"The art of prophecy is very difficult, especially about the future." - Mark Twain




              DE BILT (NETHERLANDS)

coordinates: 52.10N, 5.18E, 15m (prob: 3m)

WMO station code: 6260 (get data)

Associated with small town (pop.33000)

Terrain: flat WARM CROPS

Found 305 years with data in 1706-2010


My Comments:

-  De Bilt is the longest temperature record that I can locate, with 300 years of complete records between 1706 and 2009.

-  The station is located in a small town in Holland (although not far from the city of Utrecht).

-  De Bilt is the primary meteorological station of the Royal Dutch Meteorological Service (KNMI) and therefore can be presumed to be of high quality.

-  The long-term annual mean temperature trend over the past 300 years is +0.5C/100years.

-  Alternatively, it may be interpreted that there was zero trend from 1706 to1850, a discontinuity of about +1C and then zero trend from 1851 to 2009!

-  The historical variation in annual mean temperatures has been less in recent years (since say 1980) than in earlier years (eg higher highs between 1850 and 1950, and lower lows prior to 1840).

-  The De Bilt temperatures have been increasing since 1960, but this is not significant if one looks at the long-term data available.

-  The fact that temperatures have been increasing over the past 300 years indicates that this is not primarily caused by recent increases in atmospheric pollution and is therefore probably not induced by man.  Maybe the solar theories are correct afterall!

-  Other analysis by me indicates similar long-term temperature trends at other locations throughout the world.


The Author:   

This article was written by Brian Gunter of Narooma (NSW, Australia).  In his previous life Brian was an engineering hydrologist involved over many years in the analysis of rainfall and river flow data for the planning of water resources projects in Australia, Asia and Africa.  In recent years he has been one of the Marine Rescue NSW (formerly the Royal Volunteer Coastal Patrol) volunteer weather observers who operate the Narooma station for the Bureau of Meteorology.

Brian Gunter     

Prepared 13 October 2010