Email 1544, Oct 2000, Phil Jones: "...warmer conditions than today during many summers from 1750 to 1850...Central England also shows little change in summer since the 18th century. Autumns for CET in the 1730s were clearly warmer than today. All somewhat perplexing"

Email 1544

I have been looking at some long temperature records from Fennoscandia, particularly those put together during the IMPROVE project. This involved Anders Moberg in Stockholm and Hans Bergstrom in Uppsala. Summer temperatures for both these series which extend back to 1756 and about 1740 show warmer conditions than today during many summers from 1750 to 1850. Uppsala has clear problems between 1722-1740 so these data have been ignored. Warm summers at this time also occur at St. Petersburg (also in IMPROVE), so I partly take the view that the early records from Trondheim, Vardo (from 1830s) and Archangel (from 1810s) may be correct. Winters in all the series were much colder than today at these times. Continentality may have increased during these times (greater winter/summer contrasts). Exposure may still be a problem, but Anders believes this isn't an important factor. Some central European series in Germany and Austria show similar summer/winter trends but not quite to the same extent as in Fennoscandia. Central England also shows little change in summer since the 18th century. Autumns for CET in the 1730s were clearly warmer than today. All somewhat perplexing.